SURFACE VEHICLE
RECOMMENDED PRACTICE
J2847™-6
Issued
2015-08
AUG2015
Communication between Wireless Charged Vehicles and Wireless EV Chargers
RATIONALE
SAE J2847™-6 defines abstract messages supporting the wireless transfer of energy between EVs and the Wireless Charger/ (WEVSE). This document is based on the use cases in SAE J2836™/6 that established the wireless charging requirements.
TABLE OF CONTENTS
1. 1.1 2. 2.1 2.2 3. 4. 4.1 4.2 4.3 5. 5.1 5.2 5.3 5.4 5.5 5.6 5.7 6. 7. 7.1 7.2 7.3 7.4 7.5 7.6 8. 8.1
SCOPE .......................................................................................................................................................... 3 Purpose ......................................................................................................................................................... 3 REFERENCES .............................................................................................................................................. 4 Applicable Documents .................................................................................................................................. 4 Other Publications ......................................................................................................................................... 5 DEFINITIONS ............................................................................................................................................... 6 COMMUNICATIONS SYSTEM ARCHITECTURAL CONFIGURATIONS ................................................... 8 Functional Decomposition of a WPT System................................................................................................ 8 Shared SECC Configuration ......................................................................................................................... 9 Dedicated SECC Configuration .................................................................................................................... 9 TECHNICAL REQUIREMENTS .................................................................................................................. 11 Initialization of V2G Communication Session ............................................................................................. 11 Charging Spot Discovery ............................................................................................................................ 11 Service Discovery and Hardware Compatibility Check ............................................................................... 12 Vehicle and Charging Spot Alignment ........................................................................................................ 12 Charging Spot and Vehicle Engagement .................................................................................................... 12 Charging Spot and Vehicle Pairing ............................................................................................................. 13 Charging Cycle Phases............................................................................................................................... 14 RELATIONSHIP TO INFRASTRUCTURE COMMUNICATIONS ............................................................... 14 EV TO WEVSE COMMUNICATIONS MESSAGES AND PROCEDURES ................................................ 15 General information and definitions ............................................................................................................ 15 Message Sequences ................................................................................................................................... 15 Wireless Charge Point Discovery ............................................................................................................... 16 Protocol Handshake .................................................................................................................................... 17 Message Structure ...................................................................................................................................... 17 BodyElement Definitions ............................................................................................................................. 18 DATA TYPES .............................................................................................................................................. 31 Overview ..................................................................................................................................................... 31
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8.28.3 8.4 9.9.1 9.2 9.3 9.4 9.5 10. 11.11.1 11.2 11.3 11.4 11.5 11.6 11.7 12.12.1 12.2
Appendix A
Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 Figure 13 Figure 14 Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32
Complex Types ........................................................................................................................................... 31WP Types .................................................................................................................................................... 33 Simple data types ........................................................................................................................................ 40 STATE AND SEQUENCE DIAGRAMS ...................................................................................................... 47Primary Side State Diagram........................................................................................................................ 47 Primary Side State Descriptions ................................................................................................................. 48 Secondary Side State Diagram ................................................................................................................... 50 Secondary Side State Descriptions ............................................................................................................ 51 Sequence Diagrams .................................................................................................................................... 52 SECURITY .................................................................................................................................................. 59 XML SCHEMA ............................................................................................................................................ 60V2G_CI_Beacon.xsd ................................................................................................................................... 60 V2G_CI_AppProtocol.xsd ........................................................................................................................... 61 V2G_CI_MsgBody.xsd ................................................................................................................................ 62 V2G_CI_MsgDataTypes.xsd ...................................................................................................................... 73 V2G_CI_MsgDef.xsd .................................................................................................................................. 89 V2G_CI_MsgHeader.xsd ............................................................................................................................ 89 xmldsig-core-schema.xsd ........................................................................................................................... 90 NOTES ........................................................................................................................................................ 94Marginal Indicia ........................................................................................................................................... 94 Patent Statement ........................................................................................................................................ 94 .................................................................................................................................................................... 95 Functional decomposition of a WPT system ................................................................................................. 8WPT systems with shared SECC ................................................................................................................. 9 WPT systems with dedicated SECCs ......................................................................................................... 10 Typical high level message flow ................................................................................................................. 11 Example of pairing ambiguity ...................................................................................................................... 12 Schema diagram - V2G_BEACON ............................................................................................................. 17 Schema diagram - ChargeParameterDiscoveryReq .................................................................................. 19 Schema diagram - ChargeParameterDiscoveryRes ................................................................................... 20 Schema diagram – PowerDeliveryReq ....................................................................................................... 21 Schema diagram - PowerDeliveryRes ........................................................................................................ 21 Schema diagram - StartAlignmentReq ....................................................................................................... 22 Schema diagram - StartAlignmentRes ........................................................................................................ 23 Schema diagram - AlignmentCompleteReq................................................................................................ 23 Schema diagram - AlignmentCompleteRes ................................................................................................ 23 Schema diagram - HeartbeatReq ............................................................................................................... 24 Schema diagram - HeartbeatRes ............................................................................................................... 24 Schema diagram – PowerDemandReq ...................................................................................................... 25 Schema diagram – PowerDemandRes ....................................................................................................... 27 Schema diagram – StartAlignmentCheckReq ............................................................................................ 28 Schema diagram - StartAlignmentCheckRes ............................................................................................. 28 Schema diagram - EndAlignmentCheckReq .............................................................................................. 29 Schema diagram - EndAlignmentRes ......................................................................................................... 29 Schema diagram – WP_PreChargeReq ..................................................................................................... 30 Schema diagram – WP_PreChargeRes ..................................................................................................... 30 Schema diagram – ServiceProvider ........................................................................................................... 32 Schema diagram – ServiceProviderList ...................................................................................................... 32 Schema diagram – WP_EVChargeParameterType ................................................................................... 33 Schema diagram – WP_EVPowerDeliveryParameterType ........................................................................ 34 Schema diagram – WP_EVSEChargeParameterType ............................................................................... 35 Schema diagram – WP_EVSEStatusType ................................................................................................. 36 Schema diagram – WP_EVStatusType ...................................................................................................... 37 Schema diagram – WP_PrimaryType ......................................................................................................... 38
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Figure 33 Figure 34 Figure 35 Figure 36 Figure 37 Figure 38 Figure 39 Figure 40 Figure 41
Table 1 Table 2 Table 3 Table 4 Table 5 Table 6 Table 7 Table 8 Table 9 Table 10 Table 11 Table 12 Table 13 Table 14
1. SCOPE
Schema diagram – WP_PrimaryListType ................................................................................................... 39 Primary side state diagram ......................................................................................................................... 47 Secondary side state diagram .................................................................................................................... 50 Overall WPT message flows ....................................................................................................................... 53 Successful initiation of charging .................................................................................................................. 54 Message flow for delayed start of power transfer ....................................................................................... 55 Example message flow for active power transfer ....................................................................................... 56 Message flow for EV initiated power transfer termination ........................................................................... 57 Suspension of power transfer ..................................................................................................................... 58 Semantics and type definition for V2G_BEACON message elements ....................................................... 17 Semantics and type definition for PowerDemandReq ................................................................................ 26 Semantics and type definition for PowerDemandRes ................................................................................ 27 Semantics and type definition for ServiceProvider type ............................................................................. 32 Semantics and type definition for ServiceProviderList type ........................................................................ 32 Semantics and type definition for WP_EVChargeParameterType ............................................................. 34 Semantics and type definition for WP_EVPowerDeliveryParameterType .................................................. 35 Semantics and type definition for WP_EVSEChargeParameterType ........................................................ 36 Semantics and type definition for WP_ EVSEStatusType .......................................................................... 37 Semantics and type definition for WP_EVStatusType ................................................................................ 38 Semantics and type definition for WP_PrimaryType .................................................................................. 39 Semantics and type definition for WP_PrimaryListType ............................................................................. 39 Semantics for EVSERequestedEnergyTransferType ................................................................................. 41 Semantics for EVSESupportedEnergyTransferType .................................................................................. 42
This SAE Recommended Practice SAE J2847-6 establishes requirements and specifications for communications messages between wirelessly charged electric vehicles and the wireless charger. Where relevant, this document notes, but does not formally specify, interactions between the vehicle and vehicle operator.
This is the 1st version of this document and captures the initial objectives of the SAE task force. The intent of step 1 is to record as much information on “what we think works” and publish. The effort continues however, to step 2 that allows public review for additional comments and viewpoints, while the task force also continues additional testing and early implementation. Results of step 2 effort will then be incorporated into updates of this document and lead to a republished version. The next revision will address the harmonization between SAE J2847-6 and ISO/IEC 15118-7 to ensure interoperability. 1.1
Purpose
The primary purpose of SAE J2847-6 is to provide the communication to achieve wireless charging control irrespective of variations in the wireless charging technology employed.
SAE J2847-1 identifies the functional messaging for the Plug-In Electric Vehicle (PEV) to connect to the utility for Level 1 & 2 AC energy transfer. SAE J2847-2 specifies the messages and protocols for DC charging. This document identifies the additional messages for wireless energy transfer to the PEV.
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2. REFERENCES 2.1
Applicable Documents
The following publications form a part of this specification to the extent specified herein. Unless otherwise specified, the latest issue of SAE publications shall apply. 2.1.1
SAE Publications
Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001, Tel: 877-606-7323 (inside USA and Canada) or 724-776-4970 (outside USA), www.sae.org. J1715 J2836-1™ J2836-6™ J2847-1 J2847-2 J1939 2.1.2
Hybrid Electric Vehicle (HEV) & Electric Vehicle (EV) Terminology
Use Cases for Communication between Plug-in Vehicles and the Utility Grid (Surface Vehicle Information Report).
Use Cases for Communication between electric Vehicles and the Wireless Supply Equipment (WEVSE) Communication between Plug-in Vehicles and the Utility Grid (Surface Vehicle Recommended Practice). Communication between Plug-in Vehicles and Off-Board DC Chargers (Surface Vehicle Recommended Practice).
Recommended Practice for a Serial Control and Communications Vehicle Network
IEC Publications
Available from IEC Central Office, 3, rue de Varembe, P.O. Box 131, CH-1211 Geneva 20, Switzerland, Tel: +41 22 919 02 11, www.iec.ch. IEC 61851-1
Electric vehicle conductive charging system - Part 1: General requirements (Under revision)
IEC 61851-23 Electric vehicle conductive charging system - Part 23: D.C. electric vehicle charging station
(Under development)
IEC 61851-24 Electric vehicle conductive charging system - Part 24: Control communication protocol between off-board
d.c. charger and electric vehicle (Under development) IEC 62196-3
Plugs, socket-outlets, and vehicle couplers – Conductive charging of electric vehicles - Part 3: Dimensional interchangeability requirements for d.c. pin and contact-tube vehicle couplers (Under development)
2.1.3 ISO Publications
Available from American National Standards Institute, 25 West 43rd Street, 4th Floor, New York, NY 10036, Tel: 212-642-4900, www.ansi.org. ISO 11898-1 ISO 11898-2 ISO 15118-2
Controller area network (CAN) - Part 1: Data link layer and physical signaling Controller area network (CAN) - Part 2: High-speed medium access unit
Road vehicles - Vehicle-to-Grid Communication Interface - Part 2: Network and application protocol requirements
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Other Publications
DIN SPEC 70121 Electromobility - Digital communication between a d.c. EV charging station and an electric vehicle for
control of d.c. charging in the Combined Charging System IETF RFC 5246
The Transport Layer Security (TLS) Protocol Version 1.2 (August 2008)
IETF RFC 5280 Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) Profile (May 2008) IETF RFC 5289 IETF RFC 5480 IETF RFC 6066 IETF RFC 6961 W3C EXI 1.0 W3C XML
TLS Elliptic Curve Cipher Suites with SHA-256/384 and AES Galois Counter Mode (GCM) (August 2008) Elliptic Curve Cryptography Subject Public Key Information (March 2009) Transport Layer Security (TLS) Extensions: Extension Definitions (January 2011)
The Transport Layer Security (TLS) Multiple Certificate Status Request Extension (June 2013) Efficient XML Interchange (EXI) Format 1.0, W3C Recommendation (March 2011) Signature Syntax and Processing Version 1.1, - W3C Recommendation (April 2013)
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3. DEFINITIONS 3.1
ADVANCED METERING INFRASTRUCTURE (AMI)
AMI or Advanced Metering Infrastructure typically refers to the full measurement and collection system that includes meters at the customer site, communication networks between the customer and a service provider, such as an electric, gas, or water utility, and data reception and management systems that make the information available to the service provider. 3.2
BATTERY
See Electric Vehicle Storage Battery. 3.3
BATTERY ELECTRIC VEHICLE (BEV)
The BEV is a vehicle that receives its power solely from batteries, unlike a hybrid vehicle that may receive a portion of its power from an internal combustion engine (ICE). See also PEV. 3.4
BRANCH CIRCUIT
The circuit conductors between the final overcurrent device protecting the circuit and the equipment supplied by the circuit. It is typically an unswitched circuit from the service equipment (fuse box) to an appliance. For this application, the appliance is the Wireless Electric Vehicle Supply Equipment (WEVSE). 3.5
CAN (CONTROLLER AREA NETWORK)
Common Automotive communications network as defined by SAE J1939. 3.6
COMPATIBILITY CHECK
The PEV and the off-board charger should check if they are compatible. 3.7
ENERGY STORAGE SYSTEM (ESS)
See Rechargeble Energy Storage System. 3.8
ELECTRIC VEHICLE STORAGE BATTERY (BATTERY)
A group of electrochemical cells electrically connected in a series and/or parallel arrangement, the principle purpose of which is to provide DC electrical energy to propel the EV. May be called Rechargeble Energy Storage System (RESS), or Energy Storage System (ESS) 3.9
ELECTRIC VEHICLE COMMUNICATIONS CONTROLLER (EVCC)
3.10 FORWARD POWER FLOW (FPF)
Forward Power Flow means the direction of energy for charging a vehicle from the source to the vehicle. 3.11 HEXADECIMAL NUMBER NOTATION
In some sections of the document the signal definitions use numerical values in Hexadecimal format for clarity. For example, a number '0x01' represents the decimal integer value '1'; the number '0x0C' represents the decimal equivalent of '12'. 3.12 HOME AREA NETWORK (HAN)
A HAN is a network contained within a user's home that connects a person's digital devices, from multiple computers and their peripheral devices to telephones, VCRs, televisions, video games, home security systems, \"smart\" appliances, fax machines and other digital devices that are wired into the network.
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3.13 MESSAGE
A message may include several parameters packaged together in a group such that the entire group can be sent together over a physical layer interface. The physical layer will be defined in J2931 documents. 3.14 PLUG-IN ELECTRIC VEHICLE
Any class of vehicle BEV, PHEV, Electric Tug, etc., that can conductively receive power from the Electrical Grid where this power is then used to apply traction to the vehicle wheels. 3.15 RECHARGEABLE ENERGY STORAGE SYSTEM (RESS)
Means a system that stores energy for delivery of electric energy and which is rechargeable. See also Electric Vehicle Storage. See also subsclause 3.6. 3.16 REVERSE POWER FLOW (RPF)
Reverse Power Flow means the direction of energy for discharging a battery from the vehicle to the load. 3.17 POWER FLOW
See Forward Power Flow and Reverse Power Flow. 3.18 POWER TRANSFER COMPONENTS (PTC)
Power Transfer Components consist of all elements of the system involved in the actual power transfer (such as power electronics, rectifiers, coils, etc.). 3.19 SIGNAL UPDATE RATE
This defines the expected frequency at which a periodic signal must be received over the communications bus for proper system control 3.20 SECC
Supply Equipment Communication Controller 3.21 SECCC
Supply Equipment Common Communication Controller
3.22 WIRELESS ELECTRIC VEHICLE SUPPLY EQUIPMENT (WEVSE)
The equipment from the branch circuit to, and including, the connector that couples to the electric vehicle inlet, the purpose of which is to wirelessly transfer electric energy to an EV. This equipment is located off-board the vehicle.
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4. COMMUNICATIONS SYSTEM ARCHITECTURAL CONFIGURATIONS 4.1
Functional Decomposition of a WPT System
This section describes a simple decomposition of the WPT system into communications and PTC. The PTC consists of all elements of the system involved in the actual power transfer (such as power electronics, rectifiers, coils, etc.). The Off-board PTC is associated with the Infrastructure side and the Onboard PTC are the components installed on the EV. The communications function that supports and controls the power transfer is referred to as the Communications Controller. On the infrastructure side this is referred to as the Supply Equipment Communications Controller (SECC) and on the EV side as the Electric Vehicle Communications Controller (EVCC).
On the infrastructure side a single SECC may control multiple off-board PTCs, may be dedicated to a single PTC or may have a distributed architecture where some of the control functions are centralized and others are controlled on a per PTC basis.
Figure 1 - Functional decomposition of a WPT system
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Shared SECC Configuration
Figure 2 - WPT systems with shared SECC
In a shared SECC configuration a single SECC has visibility and (partial) control of multiple Off-board PTC. Such architecture facilitates the management and assignments of various parking slots, as well as allowing the SECC to optimize the grid load across multiple EVs in an active charging session. The control capabilities may be shared between the SECC and the Off-board PTC, e.g. foreign object detection and corresponding corrective/protective action can be performed by the off-board PTC and/or vehicle without intervention by the SECC. The division of the split of such functionality is beyond the scope of this specification. Similarly, the communications interface between the SECC and the off-board PTC is beyond the scope of this specification and may be vendor specific. 4.3
Dedicated SECC Configuration
In a dedicated SECC configuration each off-board PTC has its own controller that acts autonomously. Such a configuration has the advantage of isolating SECC failure modes to a single charging spot.
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Figure 3 - WPT Systems with dedicated SECCs
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5. TECHNICAL REQUIREMENTS
The wireless charging process differs in a number of aspects from the conductive process. In conductive charging the EVSE pylon is visible and the operator objective is to position and park the vehicle close enough to the EVSE that the vehicle power inlet is within reach of the plug at the end of the cable. The EVSE remains visible while the operator is positioning the vehicle. For the case of wireless charging the vehicle must be positioned with greater precision with respect to the primary pad. In public areas, the precise charging pad location may not be visible and will certainly not be visible as the vehicle positions itself over the pad. This difference dictates that the vehicle and operator rely on communications to achieve alignment between the primary and secondary pads.
An overview of the overall wireless charging process can be found in J2836/6.
Figure 4 - Typical high level message flow
5.1
Initialization of V2G Communication Session
This phase begins when the EV is within communication range of the charging-spot in which it will park. The EVCC connects to the WEVSE’s SECC (Association) – this connection will be used for messages for the charging process. Once the connection is working, the EVCC and the SECC will negotiate the protocol to be used (appProtocolRequest/Response). 5.2
Charging Spot Discovery
Charging Spot and Service Discovery may be supported in either a centralized, distributed or per charge-spot configuration. Charging Spot Discovery is an optional feature where a system would “advertise” the infrastructure providers, and the availability of charging spots as well as their characteristics for a number of geographically proximate charging spots (e.g. multiple WEVSE enabled spots in a parking garage).
Charging Spot discovery may be performed by means other than the vehicles communications system (e.g. smartphone, tablet, or PC)
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Figure 5 - Example of pairing ambiguity
5.3
Service Discovery and Hardware Compatibility Check
Once the protocol has been agreed, the EVCC and SECC exchange hardware compatibility information, service and payment information, and contract authentication (if needed). Note that this exchange can be as simple as an exchange of pre-defined tokens, or a list of strings. The EVCC will send it’s capabilities to the SECC, and the SECC will determine if there is enough compatibility for power transfer.
The hardware compatibility is needed first, as there is no point in determining if one can pay for a service but not use the hardware. The service discovery is necessary as there is no point in parking if one cannot pay for the charging. 5.4
Vehicle and Charging Spot Alignment
Alignment is the process where the EV moves over the charging spot and stops when the primary and secondary devices are positioned to allow for efficient power transfer.
Editor’s Note: The alignment methods available are still under study by J2954. 5.5
Charging Spot and Vehicle Engagement
The term “Engagement” is intended to differentiate certain steps and concepts from Pairing.
Engagement is an optional correlation of a charging spot with the vehicle to aid in or enable other functions. In practice it may be implemented as an optional identifier to be used for vehicle guidance (Section 5.1), for alignment of the vehicle to the pad (Section 5.4), or for aiding in the Pairing process (Section 5.5). The intent of implementing an engagement parameter is to allow for future technologies- for example vehicle navigation and more flexibility to the choice of the Pairing process.
Engagement itself is not sufficient to enable power transfer, a check of the Pairing must be performed after the vehicle is parked.
Engagement may occur at any time after Hardware Compatibility Check up until the confirmation of Pairing (a separate operation), or not at all.
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Illustrative examples of Engagement methods include, but are not limited to:
1. Private parking spot. In such a situation Engagement would be automatic with the initial association. This is also
a scenario where Engagement is not necessary and the Alignment and Pairing process might operate with the assumption that the vehicle will be parked in the assigned spot. 2. Detected Independently by the EVSE. Engagement may occur when the driver chooses one spot out of several
and communicates that decision by driving into it. In the event the EVSE has the capability to determine which spot the vehicle is choosing, the EVSE may generate the Engaged parameter without communication with the EV. It may also be the case that the EVSE does not have a need for this parameter, in which case no Engagement is performed however Alignment and a check of Pairing are. 3. Manually Identified. A user identifies and enters a parking spot into the system (e.g through the vehicle interface
or kiosk). The EV must then communicate the decision to the EVSE. 4. Charging Spot Discovery (Section 5.1). The vehicle is engaged over a system allowing the identification of a spot
(possibly with driver interaction), and then guided to the engaged spot. Communication between EV and EVSE is required here. 5.6
Charging Spot and Vehicle Pairing
Pairing is the process where an EV is positively confirmed present at a unique primary device for the purposes of power transfer. Ambiguity can arise due to multiple vehicles near an EVSE, multiple primary devices connected to a single EVSE or multiple EVSEs in a given area, including neighboring garages in a residential setting. The Pairing Process is necessary to assure the correct primary device will be activated for charging. Pairing occurs after Alignment, i.e., the vehicle is parked in the spot.
The EVSE will confirm the pairing prior to allowing power flow, this is done during the AlignmentCheck exchange. It may employ additional methods outside of this recommended practice if desired (vision, RF, etc…). A successful pairing is communicated by a positive response of the AlignmentCompleteRes message.
The following methods are currently suggested and supported by this recommended practice:
1. Pre-programmed charging spot identification. This method may only be suitable for scenarios where there is only
one charging spot per SECC (e.g. private garage). This method may also include the manual request of a specific spot through controls and displays on-board or off-board the vehicle. 2. The primary device will emit a signal (different from the WEVSE beacon) that contains a unique identifier of the
charging spot. The EVCC will inform the SECC of the identifier in a pairing request. If the SECC does not own that charging spot, it should know which SECC does own it, and can inform the EVCC that it has connected to the wrong SECC. 3. The secondary device emits a signal that contains a locally unique identifier of the EV (may be automatically
generated specifically for this purpose). The SECC will inform the EVCC if it receives the identifier – if no identifier is found in a reasonable amount of time, then the pairing has failed. 4. EVSE determined. The EVSE independently employs a method to positively associate a spot with the vehicle using
the existing communication parameters in this Recommended Practice. The employed method would be outside the scope of this practice; however, the use and communication of the results are covered here.
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Charging Cycle Phases
The messages within this document apply to the use cases for wireless charging of EVs, as specified in J2836/6. For vehicles supporting both wireless and conductive charging, the interaction between the two sub-systems needs to be considered by the system designer and is not specified. 5.7.1
Normal Charging Session
A charging session that completes without any error condition or abnormal termination is considered a normal charging session. Each charging session begins after the vehicle has achieved alignment and has three phases. 5.7.2
Initialization (Start Power Transfer)
During this phase, the vehicle and WEVSE exchange their operating limits and parameters for the upcoming charging session. Some parameters may be required (the assumption is that in the initial phase of the guideline these parameters may have more than one value), such as, operating frequency, maximum available power output, maximum vertical tolerance and nominal air-gap. Each side uses these values to perform a compatibility check and to ensure that the limits are maintained during the charging session. Additionally, an alignment check will be performed. 5.7.3
Power Transfer
During Power Transfer, the vehicle and the WEVSE will monitor the power, voltage and current readings independently to ensure that the system remains within the negotiated limits. The vehicle can request that the WEVSE increase or decrease its primary current, voltage or power. Note that if a voltage request is sent, the current will remain constant. Note that if a current request is sent, the voltage will remain constant. Note that if a power request is sent, the voltage will remain constant. The WEVSE may implement an internal ramp rate limit, such that if too large a step is requested (either up or down) then the requested parameter will ramp at a fixed rate towards that desired point.
The vehicle will control charge level based on vehicle RESS and other vehicle conditions. This phase persists until either the user or the vehicle determines that power transfer is completed. The EV may receive the trigger in terms of an indication that the desired charge level has been reached, an input from the user interface or as the result of the detection of an abnormal condition (e.g. FOD) requiring termination. 5.7.4
Termination
Normal termination occurs when the RESS reaches the desired State of Charge or can be entered by an action from the user.
6. RELATIONSHIP TO INFRASTRUCTURE COMMUNICATIONS
The messages described in this document concern interactions that are needed to control the charging process and that are transferred over the EV-WEVSE interface. Communications between the EV and Grid, and the EV and User are the subject of J2847/1 (and other specifications). These messages result in an additional control loop that may impact the charging cycle and may impact the behavior that is seen across the EV-WEVSE interface. For example, a demand response message from the grid may force the WEVSE to suspend power transfer. These effects are modeled here as “triggers” that result in appropriate state changes and messages to keep the two sides of the interface synchronized.
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7. EV TO WEVSE COMMUNICATIONS MESSAGES AND PROCEDURES 7.1
General information and definitions
A V2G message uses the EXI-based Presentation Layer. The communication between EVCC and SECC at application layer level is based on a client/server architecture. The EVCC always acts as a client (service requester) during the entire charging process, whereas the SECC always acts as a server (service responder). Hence the EVCC always initiates communication by sending a request message to the SECC which then returns the corresponding response message. All messages exchanged between EVCC and SECC are described with their syntax and their semantics in subclauses 7.3, 7.5, and 7.6. The entire XML Schema definition describing both V2G message sets is included in subclause11. V2G communication consists of two different message sets:
- - 7.2 7.2.1
V2G application layer protocol handshake messages (refer to subclause 7.4); V2G application layer messages (refer to subclause 7.5). Message Sequences
Protocol Flow Stages and Associated Messages
After connecting EV and EVSE, a network connection is established. Then, initialization of this V2G Communication Session has to be done. After getting all services offered by the EVSE, charging the battery can start. At the end of the charging process, power is switched off. The following list describes the sequence of messages which is used to control the flow: Initialization of V2G Communication Session: Check protocol compatibility, establish V2G Communication Session, exchange client-/server IDs. Messages for this activity:
− supportedAppProtocolRequest/Response − Session Setup Request/Response
Service Discovery: Discover the services offered by the EVSE, agreement on billing parameters. Messages for this activity:
− Service Discovery Request/Response
− Service and Payment Selection Request/Response − Contract Authentication Request/Response
Hardware Compatibility Check: exchange of hardware capabilities, power capabilities, etc. Messages for this activity:
− Charge Parameter Discovery Request/Response
Alignment and Pairing: start the alignment beacons, determine primary device ID, and pairing. Messages for this activity:
− StartAlignment Request/Response − EndAlignment Request/Response − Pairing Request/Response
− Start Alignment Check Request/Response
− End Alignment Check Request/Response
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Charge vehicle: Charging the EV is one possible service offered by the EVSE. The charging process is divided into three phases:
Set up charging process: Agreement on technical charging parameters, start charging process. Messages for this activity:
− WP Pre-Charge Request/Response − Power Delivery Request/Response Charging process: Energy transfer
− Power Demand Request/Response
Finalize charging process: Stop power delivery, stop charging process
− Power Delivery Request/Response − Stop Session Request/Response
After finalizing the charging process, the EV is free to move from the charging pad. 7.2.2
Basic Definitions for Error Handling
The basic error handling for a Request-Response Message Pair is based on the Response Code included in the Response Message of the SECC. Depending on the value in the Response Code, the EVCC decides if it can proceed with the standard Request-Response Message Sequence or if it has to handle an error.
In this standard, the Response Code as defined in subclause 0is interpreted by the EVCC as follows: OK: Any Value starting with “OK” or “OK_” indicates a positive response. Detailed information may be provided by
OK_ provided by FAILED_ Request-Response Message Sequence Requirements All requirements from SAE J2847/2 subclause 5.3.4 shall apply. Exception: requirements that deal specifically with conductive charging. 7.3 7.3.1 Wireless Charge Point Discovery Procedure Wireless charge point discovery covers two concepts, one is the finding of charging opportunities in a particular geographic area or along a route to be driven, and the other is the discovery of the immediate vicinity of charge spot so that an association may be established between the EV and WEVSE. Only the latter is within the scope of this specification. The EVSE will have the Access Point multicast a “Beacon Message” to any device that connects to the Access Point. If the EV cares to receive the message, it will have the wifi attached to the EV pass the “Beacon message” into the EVCC. This Beacon only needs to be broadcast when the WEVSE is available to serve a user. The Beacon shall convey enough information to allow the EV to determine if it is worthwhile to initiate a connection. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 17 of 96 7.3.2 Messages and Parameters Figure 6 - Schema diagram - V2G_Beacon Table 1 - Semantics and type definition for V2G_Beacon message elements Element/Attribute Name Type simpleType: evseType refer to 0 complexType: WP_PrimaryListType refer to 8.3.7 complexType: ServiceProviderListType refer to section 8.2.15 Semantics The ID of the EVSE EVSEID WP_PrimaryList This is a list of available primary devices for a SE. WP_PrimaryList provides the coil type, the power capability, AlignmentBeaconInfo and the ID of each coil associated with the SE. The list of Service Providers for this SE. ServiceProviderList NOTE: Refer to subclause 11.1 for the XML schema code. 7.4 7.4.1 Protocol Handshake Handshake Request-Response Message Pair Requirements from SAE J2847/2 subclause 6.2.1 shall apply. [V2G-WP-001] In the scope of SAE 2847-6, only the namespace “urn:sae:j2847-6:MsgDef” and the version number 1.0 shall be used to indicate SAE J2847/6. 7.4.2 Message definition supportedAppProtocolReq and supportedAppProtocolRes Requirements from SAE J2847/2 subclause 6.2.2 shall apply. 7.5 7.5.1 Message Structure Overview Messages defined in this document are designed to be compatible with SAE J2847/2 to the extent possible. Messages and signals will be reused wherever possible. New messages and signals will be created to support wireless power transfer. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 18 of 96 Subclause 7.5 describes the messages of the V2G messages and their contents. It is divided into the following 3 subclauses: • V2G Message definition (refer to subclause 7.5.2); • V2G Message header definition (refer to subclause 7.5.3); • V2G Message body definition (refer to subclause 7.5.4). NOTE: Refer to subclause 11 for the XML schema code. The application layer message set is signalized by the XML schema namespace \" sae:j2847-6:MsgDef\". Refer to the XML schema definition in subclause 11 for details concerning subnamespace definitions used for the message definition. 7.5.2 Message definition Message definition is unchanged from SAE J2847/2, subclause 6.3.2. 7.5.3 Message Header Definition The message header is unchanged from SAE J2847/2, subclause 6.3.3. 7.5.4 Message Body Definition The message body is unchanged from SAE J2847/2, subclause 6.3.4. 7.6 7.6.1 7.6.1.1 BodyElement Definitions Common Messages Overview Messages defined as common messages can be applied to the message sequence in any charging mode defined in ISO/IEC 15118 in addition to wireless power charging. 7.6.1.2 Session Setup Unchanged from SAE J2847/2, subclause 6.4.1.2. 7.6.1.3 Service Discovery Unchanged from SAE J2847/2, subclause 6.4.1.3. 7.6.1.4 Service and Payment Selection Unchanged from SAE J2847/2, subclause 6.4.1.4. 7.6.1.5 Contract Authentication Unchanged from SAE J2847/2, subclause 6.4.1.5. 7.6.1.6 Charge Parameter Discovery Same as SAE J2847/2, subclause 6.4.1.6, with the following modification: • Addition of a new parameter – WP_EVChargeParameter. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 19 of 96 7.6.1.6.1 Charge Parameter Discovery Handling Unchanged from SAE J2847/2, subclause 6.4.1.6. 7.6.1.6.2 Charge Parameter Discovery Request By sending the Charge Parameter Discovery Request message the EVCC provides its charging parameters to the SECC. This message provides status information about the EV and additional charging parameters, like estimated energy amounts for recharge and the point in time for the end of charge. [V2G-WP-002] The EVCC and the SECC shall implement the mandatory messages and message elements as defined in Figure 7. Figure 7 - Schema diagram - ChargeParameterDiscoveryReq [V2G-WP-003] The message elements of this message shall be used as defined section 0. [V2G-WP-004] For Wireless Power Transfer, the element “AC_EVChargeParameter” shall not be used. [V2G-WP-005] For Wireless Power Transfer, the element “DC_EVChargeParameter” shall not be used. [V2G-WP-006] For Wireless Power Transfer, the element “WP_EVChargeParameter” shall be used. 7.6.1.6.3 Charge Parameter Discovery Response Same as SAE J2847/2, subclause 6.4.1.6, with the following modification: • Addition of a new parameter – WP_EVSEChargeParameter. With the Charge Parameter Discovery Response message the SECC provides applicable charge parameters from the grid’s perspective. Next to general charge parameters of the EVSE this optionally includes further information on cost over time, cost over demand, cost over consumption or a combination of these. The term cost refers to any kind of cost specified in this version of the standard and is not limited to monetary costs. Based on this cost information the EV may optimize its charge for the requested amount of energy. [V2G-WP-007] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 8. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 20 of 96 Figure 8 - Schema diagram - ChargeParameterDiscoveryRes [V2G-WP-008] The message elements of this message shall be used as defined section 0. NOTE: By using the EVSEProcessing parameter, the EVSE can indicate to the EVCC that the processing has not finished but a response message has to be sent to fulfil the timeout and performance requirements. This allows to delay the V2G Communication Session while fulfilling the performance and timeout requirements. [V2G-WP-009] For Wireless Power Transfer, the element “AC_EVSEChargeParameter” shall not be used. [V2G-WP-010] For Wireless Power Transfer, the element “DC_EVSEChargeParameter” shall not be used. [V2G-WP-011] For Wireless Power Transfer, the element “WP_EVSEChargeParameter” shall be used. 7.6.1.7 7.6.1.7.1 Power Delivery Power Delivery Handling The Power Delivery message exchange is used to communicate maximum and minimum power capabilities between the EV and EVSE, thus providing boundaries for power transfer. 7.6.1.7.2 Power Delivery Request By sending the Power Delivery Request the EVCC requests the EVSE to switch power on and transmits the charging profile it will follow during the charging process. NOTE: The point in time this message is sent does not necessarily correlate with the start of the charging process. The onboard charger of the EV may decide on the basis of its schedule when the charging process starts. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 21 of 96 [V2G-WP-012] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 9. [V2G-WP-013] The message elements of this message shall be used as defined section 0. [V2G-WP-014] For Wireless Power Transfer, the optional element “DC_EVPowerDeliveryParameter” shall not be used. [V2G-WP-015] For Wireless Power Transfer, the optional element “WP_EVPowerDeliveryParameter” shall be used. 7.6.1.7.3 Power Delivery Response Figure 9 - Schema diagram – PowerDeliveryReq After receiving the Power Delivery Request message of the EVCC, the SECC sends the Power Delivery Response message including information if power will be available. [V2G-WP-016] The EVCC and the SECC shall implement the mandatory messages and message elements as defined in Figure 10. Figure 10 - Schema diagram - PowerDeliveryRes SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 22 of 96 [V2G-WP-017] The message elements of this message shall be used as defined section 0. [V2G-WP-018] The SECC shall always accept the ChargingProfile of the EVCC if it does not exceed the PMax values of all PMaxScheduleEntry elements according to the chosen SAScheduleTuple element in the Charge Parameter Discovery Response message. [V2G-WP-019] The SECC shall send the negative response code FAILED_ChargingProfileInvalid in the PowerDelivery response message if the EVCC sends a ChargingProfile which is not adhering to the PMax values of all PMaxScheduleEntry elements according to the chosen SAScheduleTuple element in the Charge Parameter Discovery Response message. [V2G-WP-020] For Wireless Power Transfer, the element “AC_EVSEStatus” shall not be used. [V2G-WP-021] For Wireless Power Transfer, the element “DC_EVSEStatus” shall not be used. [V2G-WP-022] For Wireless Power Transfer, the element “WP_EVSEStatus” shall be used. 7.6.1.8 Session Stop Unchanged from SAE J2847/2, subclause 6.4.1.8. 7.6.2 7.6.2.1 WP-Messages Overview Messages defined as WP-Messages shall be applied to wireless power charging message sequence only. 7.6.2.2 Alignment The EV shall send a “Start Alignment” message to the WEVSE to initiate the alignment process. In response to the receipt of that message the WEVSE shall activate the appropriate alignment assist systems and send a response in a “WP_EVSEStatus” message indicating that the WEVSE has entered the “Awaiting Alignment (AA)” state. In the AA state either the EV or WEVSE shall be constantly computing an alignment score, that can be used as guidance to indicate when a sufficiently high level of coupling is possible to allow safe charging. This information may be made available to the user via the user interface (on the EV or WEVSE, as appropriate). Upon successful alignment, the AA state will be exited when the EV issues an “Alignment Complete” message. The WEVSE may at that stage verify independently that efficient and compliant charging is possible. Editor’s Note: The alignment methods available are still under study by J2954. 7.6.2.2.1 StartAlignmentReq This message is from the EV asking for the alignment beacons to be enabled and an optional TimeOut value (in minutes) specifies how long until the alignment process fails with no request from the EV. The request from the EV may be sent cyclically with the TimeOut value. [V2G-WP-023] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 11. Figure 11 - Schema diagram - StartAlignmentReq SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 23 of 96 [V2G-WP-024] The message elements of this message shall be used as defined section 0. 7.6.2.2.2 StartAlignmentRes This message only contains the response back to the EV as to whether the alignment beacons have been enabled or not. [V2G-WP-025] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 12. Figure 12 - Schema diagram - StartAlignmentRes [V2G-WP-026] The message elements of this message shall be used as defined section 0. 7.6.2.2.3 AlignmentCompleteReq The EV indicates to the SE that the alignment process has completed, and provides the ID of the primary device. [V2G-WP-027] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 13. Figure 13 - Schema diagram - AlignmentCompleteReq [V2G-WP-028] The message elements of this message shall be used as defined section 0. 7.6.2.2.4 AlignmentCompleteRes This message indicates whether the EVSE accepts the pairing of EV / Primary Device. [V2G-WP-029] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 14. Figure 14 - Schema diagram - AlignmentCompleteRes SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 24 of 96 [V2G-WP-030] The message elements of this message shall be used as defined section 0. 7.6.2.3 Heartbeat The Heartbeat message is sent whenever there is absence of regular traffic on the link to verify that the communication capability is still available. Note that the Heartbeat message is not necessary – the EV could send a power request instead. 7.6.2.3.1 Heartbeat Request [V2G-WP-031] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 15. Figure 15 - Schema diagram - HeartbeatReq [V2G-WP-032] The message elements of this message shall be used as defined section 0. 7.6.2.3.2 Heartbeat Response [V2G-WP-033] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 16. Figure 16 - Schema diagram - HeartbeatRes [V2G-WP-034] The message elements of this message shall be used as defined section 0. 7.6.2.4 7.6.2.4.1 Power Demand Power Demand Handling For WP charging control cyclic exchange of requested current, voltage or power from EV side is necessary. 7.6.2.4.2 Power Demand Request By sending the Power Demand Request the EV requests a certain current, voltage or power from EVSE. [V2G-WP-035] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 17. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 25 of 96 Figure 17 - Schema diagram – PowerDemandReq NOTE: EVTargetChargeParameter types of current or power do not change the existing voltage settings. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 26 of 96 [V2G-WP-036] The message elements of this message shall be used as defined in Table . Table 2 - Semantics and type definition for PowerDemandReq Element Name WP_EVStatus Type complexType: WP_EVStatusType refer to subclause 8.3.5 complexType PhysicalValueType refer to subclause 8.2.2 complexType PhysicalValueType refer to subclause 8.2.2 complexType PhysicalValueType refer to subclause 8.2.2 simpleType Boolean Semantics Current status of the EV EVTargetChargeParameter Instantaneous current, voltage or power requested by the EV EVMaximumPowerLimit Optional Element: Maximum power allowed by the EV Present input current, voltage or power of the EV. EVPresentChargeParameter BulkChargingComplete Optional Element: If set to TRUE, the EV indicates that bulk charge (approx. 80 % SOC) is complete. If set to TRUE, the EV indicates that full charge (100 % SOC) is complete. Optional Element: Estimated or calculated time until full charge (100 % SOC) is complete Optional Element: Estimated or calculated time until bulk charge (approx. 80 % SOC) is complete ChargingComplete RemainingTimeToFullSoC simpleType Boolean complexType PhysicalValueType refer to subclause 8.2.2 complexType PhysicalValueType refer to subclause 8.2.2 RemainingTimeToBulkSoC NOTE: The value of EVMaximumPowerLimit that is sent in any PowerDemandReq message shall not exceed the value of EVMaximumPowerLimit that is sent in the ChargeParameterDiscoveryReq message. 7.6.2.4.3 Power Demand Response After receiving the Power Demand Request message of the EVCC, the SECC sends the Power Demand Response message informing the EV about EVSE status and present EVSE output power. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 27 of 96 [V2G-WP-037] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 18. Figure 18 - Schema diagram – PowerDemandRes [V2G-WP-038] The message elements of this message shall be used as defined in Table . Table 3 - Semantics and type definition for PowerDemandRes Element Name ResponseCode Type simpleType: responseCodeType enumeration refer to subclause 0 for the type definition complexType: WP_EVSEStatusType refer to subclause 8.3.4 complexType PhysicalValueType refer to subclause 8.2.2 simpleType Boolean complexType PhysicalValueType refer to subclause 8.2.2 Semantics Response Code indicating the acknowledgment status of any of the V2G messages received by the SECC. WP_EVSEStatus Current status of the EVSE EVSEPresentChargeParameter Present output current, voltage or power of the EVSE. The physical type must be the same type as in the PowerDemandReq message. If set to TRUE, the EVSE has reached its power limit. Optional Element: Maximum power the EVSE can deliver EVSEPowerLimitAchieved EVSEMaximumPowerLimit 7.6.2.5 StartAlignmentCheck Alignment Check is where the EVSE provides a certain amount of power to the EV. The EV measures this power and tells the EVSE how much power has been received. If the received power is X% (A specific value is determined by relevant document such as SAE J2954) of the transmitted power, then the alignment check is considered successful. The EV shall send a “Start Alignment Check Request” message to the WEVSE to initiate the alignment check process. In response to the receipt of that message the WEVSE shall activate the appropriate power transfer systems and send a response in a “Start Alignment Check Response” message indicating amount of power being transferred to the EV. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 28 of 96 7.6.2.5.1 StartAlignmentCheckReq This message is from the EV asking for the alignment check to be enabled. An optional MaxPower value specifies the maximum power that the EV expects to receive. [V2G-WP-039] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 11. Figure 19 - Schema diagram – StartAlignmentCheckReq [V2G-WP-040] The message elements of this message shall be used as defined section 0. 7.6.2.5.2 StartAlignmentCheckRes This message contains the response back to the EV as to whether the alignment check process has been enabled, as well as the EVSEPresentPower (power being transferred from the EVSE). [V2G-WP-041] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 1220. Figure 20 - Schema diagram - StartAlignmentCheckRes [V2G-WP-042] The message elements of this message shall be used as defined section 0. 7.6.2.6 EndAlignmentCheck The EV shall send a “End Alignment Check Request” message to the WEVSE to terminate the alignment check process. The EV shall indicate the amount of power being received as well as the current EV status. In response to the receipt of that message the WEVSE shall terminate the power transfer and send a response in a “End Alignment Check Response” message indicating the EVSE status. 7.6.2.6.1 EndAlignmentCheckReq This message is from the EV asking for the alignment check to be finished. The message contains EVPresentPower value as well as the EV Status. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 29 of 96 [V2G-WP-043] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 11. Figure 21 - Schema diagram - EndAlignmentCheckReq [V2G-WP-044] The message elements of this message shall be used as defined section 0. 7.6.2.6.2 EndAlignmentCheckRes The EVSE will terminate power transfer upon receipt of the EndAlignmentCheckReq message. This message contains the EVSE status as well as the ResponseCode. [V2G-WP-045] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 12. Figure 22 - Schema diagram - EndAlignmentRes [V2G-WP-046] The message elements of this message shall be used as defined section 0. 7.6.2.7 WP_Precharge WP_PreCharge is used for setting the EVSE power transfer values. The EV will send the desired current, voltage and power settings. 7.6.2.7.1 WP_PreChargeReq With the WP_PreCharge Request the EV asks the EVSE to set power transfer values (current, voltage and power). This allows the EV to use current control or power control during the power transfer loop. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 30 of 96 [V2G-WP-047] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 11. Figure 23 - Schema diagram – WP_PreChargeReq [V2G-WP-048] The message elements of this message shall be used as defined section 0. 7.6.2.7.2 WP_PreChargeRes After receiving the WP_PreCharge Request message of the EVCC, the SECC sends the WP_PreCharge Response message informing the EV of the EVSE status and the values to be used for power transfer (current, voltage and power). [V2G-WP-049] The EVCC and the SECC shall implement the mandatory message and message elements as defined in Figure 12. Figure 24 - Schema diagram – WP_PreChargeRes [V2G-WP-050] The message elements of this message shall be used as defined section 0. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 31 of 96 8. DATA TYPES 8.1 Overview In this section data types are defined which are used in the messages. Complex data types are composed of several elements which themselves are based on simple data types. 8.2 8.2.1 Complex Types ChargingProfileType Unchanged from SAE J2847/2, subclause 4.2.6. 8.2.2 PaymentOptionsType Unchanged from SAE J2847/2, subclause 4.2.68. 8.2.3 PhysicalValueType Unchanged from SAE J2847/2, subclause 4.2.69. 8.2.4 PMaxScheduleType Unchanged from SAE J2847/2, subclause 4.2.63. 8.2.5 PMaxScheduleEntryType Unchanged from SAE J2847/2, subclause 4.2.65. 8.2.6 ProfileEntryType Unchanged from SAE J2847/2, subclause 4.2.72. 8.2.7 RelativeTimeIntervalType Unchanged from SAE J2847/2, subclause 4.2.75. 8.2.8 SAScheduleListType Unchanged from SAE J2847/2, subclause 4.2.80. 8.2.9 SAScheduleTupleType Unchanged from SAE J2847/2, subclause 4.2.81. 8.2.10 SelectedServiceListType Unchanged from SAE J2847/2, subclause 4.2.88. 8.2.11 SelectedServiceType Unchanged from SAE J2847/2, subclause 4.2.89. 8.2.12 ServiceChargeType Unchanged from SAE J2847/2, subclause 4.2.92. Note that new semantics for EVSESupportedEnergyTransferType are defined in subclause 8.4.16. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 32 of 96 8.2.13 ServiceTagType Unchanged from SAE J2847/2, subclause 4.2.98. 8.2.14 ServiceProviderType [V2G-WP-051] The EVCC and the SECC shall implement this type as defined in Figure 25. Figure 25 - Schema diagram – ServiceProvider Table 4 - Semantics and type definition for ServiceProvider Type Element Name ServiceID Type simpleType: ServiceIDType refer to subclause 0 SimpleType: ServiceNameType refer to subclause 8.4.31 Semantics Identifier of the Service Provider ServiceName Name of the Service Provider. 8.2.15 ServiceProviderListType [V2G-WP-052] The EVCC and the SECC shall implement this type as defined in Figure 26. Figure 26 - Schema diagram – ServiceProviderList Table 5 - Semantics and type definition for ServiceProviderList Type Element Name ServiceProvider Type complexType: ServiceProvider refer to subclause 8.2.14 Semantics Information about the Service Provider 8.2.16 ServiceType Unchanged from SAE J2847/2, subclause 4.2.99. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 33 of 96 8.3 8.3.1 WP Types WP_EVChargeParameterType [V2G-WP-053] The EVCC and the SECC shall implement this type as defined in Figure 27. Figure 27 - Schema diagram – WP_EVChargeParameterType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 34 of 96 [V2G-WP-054] The message element shall be used as defined in Table . Table 6 - Semantics and type definition for WP_EVChargeParameterType Element Name WP_EVStatus Type complexType WP_EVStatusType refer to subclause 8.4.37 complexType PhysicalValueType refer to subclause 8.2.2 complexType PhysicalValueType refer to subclause 8.2.2 complexType PhysicalValueType refer to subclause 8.2.2 simpleType: percentValueType byte (range: 0-100) simpleType: percentValueType byte (range: 0-100) simpleType: enumeration refer to subclause 8.4.1 simpleType: enumeration refer to subclause 0 Semantics Current status of the EV EVMaximumPowerLimit Maximum power supported by the EV EVEnergyCapacity Optional Element: Maximum energy capacity supported by the EV Optional Element: Amount of energy the EV initially wants from the EVSE Optional Element: SOC at which the EV considers the battery to be fully charged Optional Element: SOC at which the EV considers a fast charging process to end List of alignment methods supported by the EV EVEnergyRequest FullSOC BulkSOC AlignmentMethod PairingMethod List of pairing methods supported by the EV 8.3.2 WP_EVPowerDeliveryParameterType [V2G-WP-055] The EVCC and the SECC shall implement this type as defined in Figure 28. Figure 28 - Schema diagram – WP_EVPowerDeliveryParameterType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 35 of 96 Table 7 - Semantics and type definition for WP_EVPowerDeliveryParameterType Element Name WP_EVStatus Type complexType WP_EVStatusType refer to subclause 8.4.37 simpleType: Boolean Semantics Current status of the EV BulkChargingComplete Optional Element: True when the EV considers the battery to be at or above Bulk Charging level. True when the EV considers the battery to be at Full Charging level. ChargingComplete simpleType: Boolean 8.3.3 WP_EVSEChargeParameterType [V2G-WP-056] The EVCC and the SECC shall implement this type as defined in Figure 29. Figure 29 - Schema diagram – WP_EVSEChargeParameterType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 36 of 96 [V2G-WP-057] The message element shall be used as defined in Table . Table 8 - Semantics and type definition for WP_EVSEChargeParameterType Element Name WP_EVSEStatus Type complexType WP_EVSEStatusType refer to subclause 8.3.4 complexType PhysicalValueType refer to subclause 8.2.3 Semantics Current status of the EV EVSEMaximumPowerLimit Maximum power supported by the EVSE EVSEMinimumTransferablePower complexType PhysicalValueType refer to subclause 8.2.3 EVSEEnergyToBeDelivered complexType PhysicalValueType refer to subclause 8.2.3 complexType WP_PrimaryListType Refer to subclause 8.3.7 simpleType: enumeration refer to subclause 8.4.1 simpleType: enumeration refer to subclause 0 Minimum transferable power that the EVSE can transmit and still transmit power Optional Element: Energy to be delivered to the EV List of information on the primary devices attached to the EVSE WP_PrimaryList AlignmentMethod EVSE’s preferred alignment method. PairingMethod EVSE’s preferred pairing method. 8.3.4 WP_EVSEStatusType [V2G-WP-058] The EVCC and the SECC shall implement this type as defined in Figure 30. Figure 30 - Schema diagram – WP_EVSEStatusType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 37 of 96 Table 9 - Semantics and type definition for WP_ EVSEStatusType Element Name Type Semantics WP_EVSEStatus simpleType WP_EVStatusCode refer to subclause 8.4.37 simpleType unsignedInt Current status of the EVSE NotificationMaxDelay The SECC uses the NotificationMaxDelay element in the EVSEStatus to indicate the time until it expects the EVCC to react on the action request indicated in EVSENotification. If the target time is not in the future, the EVCC is expected to perform the action immediately. This value is used by the SECC to influence the behaviour of the EVCC. The EVSENotification contains an action that the SECC wants the EVCC to perform. The requested action is expected by the EVCC until the time provided in NotificationMaxDelay. If the target time is not in the future, the EVCC is expected to perform the action immediately. During normal operation the value of EVSENotification is set to “None”. EVSENotification simpleType EVSENotificationType enumeration refer to subclause 8.4.15 for the type definition [V2G-WP-059] For Wireless Power Transfer charging according to SAE J2847/6, the value of EVSENotification shall always be set to “None”. 8.3.5 WP_EVStatusType [V2G-WP-060] The EVCC and the SECC shall implement this type as defined in Figure 31. Figure 31 - Schema diagram – WP_EVStatusType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 38 of 96 Table 10 - Semantics and type definition for WP_EVStatusType Element Name EVReady WP_EVErrorCode Type simpleType: Boolean simpleType: WP_EVErrorCodeType enumeration refer to subclause 8.4.33 for the type definition simpleType: Boolean Semantics If set to TRUE, the EV is ready to charge. Indicates the EV internal status. EVCabinConditioning Optional Element: Vehicle Cabin Conditioning, The EV is using energy from the power delivered to heat or cool the passenger compartment. Optional Element: Vehicle RESS Conditioning, The EV is using energy from the power delivered to condition the RESS to a target temperature. Optional Element: State of charge of the EV’s battery (RESS) EVRESSConditioning simpleType: Boolean EVRESSSOC simpleType: percentValueType byte (range: 0-100) 8.3.6 WP_PrimaryType [V2G-WP-061] The EVCC and the SECC shall implement this type as defined in Figure 32. Figure 32 - Schema diagram – WP_PrimaryType SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 39 of 96 Table 11 - Semantics and type definition for WP_PrimaryType Element Name PDID Coil PowerCapability AlignmentMethod PairingMethod ACPlugAvailable DCPlugAvailable Type simpleType refer to subclause 8.4.19 simpleType refer to subclause 8.4.6 simpleType refer to subclause 8.4.20 simpleType refer to subclause 8.4.1 simpleType refer to subclause 0 simpleType: boolean simpleType: boolean Semantics Identifier for the primary device Physical type of coil Power class of primary device Indicates what type of alignment method is supported at the primary device. Indicates what type of pairing method is supported at the primary device. Indicates if an AC plug is available at the primary device. Indicates if a DC plug is available at the primary device. 8.3.7 WP_PrimaryListType [V2G-WP-062] The EVCC and the SECC shall implement this type as defined in Figure 33. Figure 33 - Schema diagram – WP_PrimaryListType Table 12 - Semantics and type definition for WP_PrimaryListType Element Name WP_Primary Type complexType: WP_Primary refer to subclause 8.3.6 Semantics Identifier for the primary device SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 40 of 96 8.4 8.4.1 Simple data types AlignmentMethod List of alignment method types. The alignment method info will be used in the WEVSE Beacon (see section 7.3). Enumeration None Magnetic MagneticAux BTLE RF 8.4.2 Charger Protocol Version Semantics No beacon Magnetic using existing coils Magnetic using auxiliary coils Bluetooth LE RF as per IEC 61980-2 This is sent at the beginning of the charging session in order to coordinate which messages and parameters can be used. 8.4.3 Charger Maximum Power Limit This parameter is the maximum power that can be delivered to the EV. The WEVSE can dynamically change this value throughout the charging session (as in the case where a utility demand reduces the available power). The parameter will be expressed as a Physical_Value_Type. 8.4.4 Charging Complete This is the parameter indicates that the EV has reached the desired charge level. 8.4.5 Charging_Pad_Id This parameter is the MAC address of the Primary Device expressed as six hex Binary encoded bytes. 8.4.6 CoilType List of possible coil types for a SE. The CoilType will be used in the WEVSE Beacon (see subclause 7.3). Enumeration Undefined Circular Solenoid DoubleD Semantics undefined circular coil solenoid double-d SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 41 of 96 8.4.7 DateTimeNow Unchanged from SAE J2847/2, subclause 4.2.10. 8.4.8 Display String This parameter encodes a character string that is meant for display on the user interface and has no direct impact on the control of the charging process. 8.4.9 EVCCID Unchanged from SAE J2847/2, subclause 4.2.27. 8.4.10 EVPresentPower This parameter is the amount of power the EV is presently receiving. The parameter will be expressed as a Physical_Value_Type. 8.4.11 EVRequestedEnergyTransfer Updated from SAE J2847/2, subclause 4.2.32. Available charging types or methods, supported by the EV. [V2G-WP-063]The EV shall use the EVSERequestedEnergyTransferType (enumeration) as described in Table 13. Table 13 - Semantics for EVSERequestedEnergyTransferType EnergyTransferType AC_single_phase_core AC_three_phase_core DC_core DC_extended DC_combo_core DC_dual AC_core1p_DC_extended AC_single_DC_core AC_single_phase_three_phase_core_DC_extended AC_core3p_DC_extended WP_WPT1 WP_WPT2 WP_WPT3 Offered charging service Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Class 1 WPT transfer Class 2 WPT transfer Class 3 WPT transfer SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 42 of 96 8.4.12 EVSEID Unchanged from SAE J2847/2, subclause 4.2.40. 8.4.13 EVSEPresentPower This parameter is the amount of power the EVSE is presently transfering. The parameter will be expressed as a Physical_Value_Type. 8.4.14 EVSEProcessing Unchanged from SAE J2847/2, subclause 4.2.52. 8.4.15 EVSENotification Unchanged from SAE J2847/2, subclause 4.2.47. 8.4.16 EVSESupportedEnergyTransfer Updated from SAE J2847/2, subclause 4.2.22. Available charging types or methods, supported by the EVSE. [V2G-WP-064] The SECC shall use the EVSESupportedEnergyTransferType (enumeration) as described in Table 14. Table 14 - Semantics for EVSESupportedEnergyTransferType EnergyTransferType AC_single_phase_core AC_three_phase_core DC_core DC_extended DC_combo_core DC_dual AC_core1p_DC_extended AC_single_DC_core AC_single_phase_three_phase_core_DC_extended AC_core3p_DC_extended WP_WPT1 WP_WPT2 WP_WPT3 Offered charging service Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Not used for Wireless Power Transfer. Class 1 WPT transfer Class 2 WPT transfer Class 3 WPT transfer SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 43 of 96 8.4.17 PairingType Enumeration of pairing methods. This will be used with hardware compatibility. Enumeration None Magnetic MagneticAux BTLE RF 8.4.18 PaymentOptionType The payment options an EVSE offers to the vehicle indicating what method could be chosen to pay for the services. The vehicle can only select one payment method for all services used. NOTE: Only the payment option “external payment” shall be used, since detailed payment options are not yet defined. Unit Name Description Contract Not used for Wireless Power Transfer. ExternalPayment Indicates that external payment methods are being used to enable the charge process. 8.4.19 PDID Primary Device ID, the MAC address of the Primary Device expressed as six hex Binary encoded bytes. 8.4.20 PowerCapabilitiesType List of power capabilities for a SE. The power capability will be used in the WEVSE Beacon (see section 7.3). Enumeration Undefined WP_WPT1 WP_WPT2 WP_WPT3 Semantics No beacon Magnetic using existing coils Magnetic using auxiliary coils Bluetooth LE RF as per IEC 61980-2 Semantics undefined WPT1 WPT2 WPT3 8.4.21 protocolNamespaceType Unchanged from SAE J2847/2, subclause 4.2.73. 8.4.22 ReadyToChargeState Unchanged from SAE J2847/2, subclause 4.2.74. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 44 of 96 8.4.23 ResponseCode Unchanged from SAE J2847/2, subclause 4.2.78. Additional error codes are defined below. XML Response Code Enumeration FAILED_AlignmentCheckFailed FAILED_LostAlignment 8.4.24 ServiceCategory Unchanged from SAE J2847/2, subclause 4.2.90. 8.4.25 ServiceScope Unchanged from SAE J2847/2, subclause 4.2.96. 8.4.26 Session_ID_Type This parameter is communication session identifier. It is used to uniquely identify a communication session between an EVCC and a SECC. The parameter is an 8 hex byte string, and is generated by the SECC. 8.4.27 Start Unchanged from SAE J2847/2, subclause 4.2.101. 8.4.28 State_Id Comments / Description Alignment check failed. Primary and Secondary devices are no longer in alignment. State Designator OOS SB SI AA AL PT_R PT_A ST_O EE 8.4.29 State_of_Charge Out-of-Service Stand-by Service Initiated State Awaiting-Alignment (Applies to Primary only) Aligning (Applies to Secondary only) Power-Transfer-Ready Power-Transfer-Active Service Terminated - Occupied (Applies to Primary only) Error-Exception This parameter specifies the current SOC of the vehicle battery in terms of full charge percentage. The parameter will be expressed as a value from 0 to 100 (byte). SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 45 of 96 8.4.30 ServiceID This parameter specifies the identifier of the Service Provider. The parameter will be expressed as a short integer. 8.4.31 ServiceName This parameter specifies the name of the Service Provider. The parameter is limited to 32 characters in length. 8.4.32 Unit Defines the unit of the PhysicalValueType. Allowed values for the Unit are: Unit Name Unit Symbol Physical Unit Minimum Value Hour h Time in hours 0 Minute m Time in minutes 0 Second s Time in seconds 0 Current A Amps 0 Voltage V Volts 0 Power W Watt 0 Energy Wh Watt-hour 0 8.4.33 Vehicle Energy Capacity This parameter is the maximum designed energy capacity allowed by the vehicle manufacturer. The parameter will be expressed as a Physical_Value_Type. 8.4.34 Vehicle Protocol Version This is sent at the beginning of the charging session in order to coordinate which messages and parameters can be used. 8.4.35 Vehicle RESS SOC This parameter represents the relative charge level as a percentage of the full energy storage of the Vehicle RESS. The parameter will be expressed as a value from 0 to 100 (byte). 8.4.36 WP_EVErrorCode Updated from SAE J2847/2, subclause 4.2.26 with additional codes. Maximum Value 72 4320 259200 400 1000 200000 200000 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 46 of 96 The EVCC may use the following addition codes: Element Name FAILED_AlignmentFailure FAILED_ThermalEvent FAILED_LossOfAlignment FAILED_InternalSystemError FAILED_FatalError FAILED_CommunicationsTimeOut FAILED_CommunicationsFailure Semantics The EV was not able to align the secondary properly with the primary. Excessive heat build up in a charging system or component of the charging system. The vehicle has drifted out of alignment. Application layer time out of message flow Communications failure detected on a basis other than application layer message time out. 8.4.37 WP_EVSEStatusCode Updated from SAE J2847/2, subclause 4.2.53 with additional codes. The EVSE may use the following addition codes: Value EVSE_FOD EVSE_AlignmentTimeOut EVSE_AlignmentFailure EVSE_ThermalEvent EVSE_LOP EVSE_LossOfAlignment EVSE_InternalSystemError EVSE_FatalError EVSE_ParameterOutOfRange Definition Foreign Object Detected Alignment Time Out Alignment Failure Thermal Event Living Object Protection Loss of Alignment Internal System Error Fatal Error Requested Parameter Value out of Range Comments / Description Foreign object in path of charging pads The vehicle did not achieve alignment within the time period allowed by the vehicle alignment assist system The EV was not able to align the secondary properly with the primary. Excessive heat build up in a charging system or component of the charging system. Intrusion of a living object in the “excluded” area has been detected. The vehicle has drifted out of alignment Sent if the EV requests power, current or voltage levels that are not supported by the WEVSE. Application layer time out of message flow Communications failure detected on a basis other than application layer message time out. EVSE_CommunicationsTimeOut Communications Time Out EVSE_CommunicationsFailure Communications Failure SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 47 of 96 9. STATE AND SEQUENCE DIAGRAMS 9.1 Primary Side State Diagram Figure 34 - Primary side state diagram SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 48 of 96 9.2 9.2.1 Primary Side State Descriptions Out-of-Service (OOS) In the OOS state the WEVSE is not available for the transfer of power. The communication channel may be available to indicate that the WEVSE is in the OOS state. The WEVSE exits this state once it has determined that it is available to transfer power. The trigger for this may be one of the following: • • • 9.2.2 Maintenance action Trigger by utility indicating power available Internal clearing of error condition Stand-by (SB) In the SB state the WEVSE is able to transfer power and its communications capability is functioning normally. The WEVSE can advertise its availability and is able to establish a connection with the EV. Compatibility information can be exchanged as a part of the connection establishment phase. The SB state is exited in response to a connection establishment request from an EV. 9.2.3 Service Initiated (SI) In the SI state the WEVSE has a communications association with an EV. Compatibility information can be exchanged as a part of the connection establishment phase. The EV may also request alignment support services from the WEVSE, if provided by the WEVSE. The state is exited normally upon successful connection and initiation of alignment support. 9.2.4 Awaiting-Alignment (AA) In the AA state the WEVSE is waiting for the EV to align itself with the primary. The state has a normal exit mode upon successful completion of alignment and alignment complete message from the EV. Inability for the vehicle to align itself in a specified time will result in an error condition. The vehicle can clear the error by resending the start alignment message and the WEVSE will return to the AA state. In case the vehicle departs, the WEVSE will return to the SB state. 9.2.5 Power-Transfer-Ready (PT_R) In the PT_R state the WEVSE is ready to transfer power to the EV but may not be actively transferring power. (This state accommodates delayed start of charging as well as smart charging). The state is exited normally upon receipt of a trigger to transfer power. The trigger may be one of the following: • • User action Smart Charging triggers o Time of day trigger o Rate based trigger o Load based trigger SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 49 of 96 9.2.6 Power-Transfer-Active (PT_A) In the PT_A state the WEVSE is actively transferring power to the EV and all monitoring activity is active to assure the integrity of the charging process. The PT_A state may be exited to the PT_R state in response to: • • control triggers from the grid that provide for temporary interruption of power transfer. control triggers from the EV that provide for temporary interruption of power transfer. The PT_A state may be exited to the ST_O state in response to control triggers from the EV that provide for interruption of power transfer. The PT_A state may be exited to the ST_O state by an indication that charging is to be terminated. Specific triggers for normal termination include the following: • • User action Termination request from EV o Desired state of charge has been reached • Termination Request from Infrastructure o Financial transaction based triggers 9.2.7 Service Terminated Occupied (ST_O) In the ST_O state the power transfer has been terminated and the communications association with the EV has been terminated; but the EV still occupies the parking space and the WEVSE is therefore unable to provide service to another user. 9.2.8 Error-Exception (EE) In the EE state the charging process is interrupted. There are two types of errors/exceptions that may occur; those that are defined as recoverable and those that are unrecoverable. The latter will result in the state transitioning from the EE state to the OOS state. For the former type of exception the system may try to recover by verifying that the error condition has cleared. The charging session may then proceed from an established recovery point. Repeated occurrences of recoverable exceptions in a short timespan may be defined as becoming non-recoverable. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 50 of 96 9.3 Secondary Side State Diagram Figure 35 - Secondary side state diagram SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 51 of 96 9.4 9.4.1 Secondary Side State Descriptions Out-of-Service (OOS) In the OOS state the EV on-board charging system is not available for the transfer of power. The communication channel may be available. The EV on-board charging system exits this state once it has determined that it is available to transfer power. The trigger for this may be one of the following: • • 9.4.2 Maintenance action by user or mechanic Internal clearing of error condition Stand-by (SB) In the SB state the EV on-board charging system is able to transfer power and its communications capability is functioning normally. The SB state is exited in when a connection is established with a WEVSE . 9.4.3 Service Initiated (SI) In the SI state the EV on-board charging system has a communications association with an WEVSE. Compatibility information can be exchanged as a part of the connection establishment phase. The EV may also request alignment support services from the WEVSE, if provided by the WEVSE. The state is exited normally upon successful connection, and initiation of alignment support. 9.4.4 Aligning (AL) In the AL state the EV is aligning itself with the primary. The state has a normal exit mode upon successful completion of alignment (along with an Alignment Complete message sent to the WEVSE), determination may be made by an automated parking system or the human operator in response to indication via the HMI. The state is exited normally upon successful alignment and pairing. Inability for the vehicle to align itself in a specified time will result in a recoverable error condition. 9.4.5 Power-Transfer-Ready In the PT_R state the EV on-board charging system is ready to transfer power to the EV but may not be actively transferring power. (This state accommodates delayed start of charging as well as smart charging). The state is exited normally upon receipt of a trigger to transfer power. The trigger may be one of the following: • • User action Programmatic triggers o Time of day trigger o Rate based trigger o SOC based trigger o Others SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 52 of 96 9.4.6 Power-Transfer-Active (PT_A) In the PT_A state the EV on-board charging system is actively transferring power to the EV and all monitoring activity is active to assure the integrity of the charging process. The PT_A state may be exited to the PT_R state in response to: • • Indications from the WEVSE that a temporary interruption of power transfer is about to occur. Control triggers from the EV that provide for temporary interruption of power transfer. The PT_A state may be exited to the SB state by an indication that charging is to be terminated. Specific triggers for normal termination include the following: • • User action Termination request from EV o Desired state of charge has been reached • Termination Request from Infrastructure o Financial transaction based triggers 9.4.7 Error-Exception (EE) In the EE state the charging process is interrupted. There are two types of errors/exceptions that may occur; those that are defined as recoverable and those that are unrecoverable. The latter will result in the state transitioning from the EE state to the OOS state. For the former type of exception the system may try to recover by verifying that the error condition has cleared. The charging session may then proceed from an established recovery point. Repeated occurrences of recoverable exceptions in a short timespan may be defined as becoming non-recoverable. 9.5 9.5.1 Sequence Diagrams Overall High Level Message Flows The following is a typical message flow that may be used to support WPT. Note that the high level flow here includes messages/information that may come form infrastructure communications beyond the SECC. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 53 of 96 Figure 36 - Overall WPT message flows 9.5.2 TBD Message Flow Association, Pairing and Alignment SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 54 of 96 9.5.3 Message Flow Initiate Charging The below example shows the message flow for successful initiation of power transfer with delayed Figure 37 - Successful initiation of charging SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 55 of 96 9.5.4 Message Flow in Support of Delayed Charging – WEVSE Start Condition Detection Figure 38 - Message flow for delayed start of power transfer SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 56 of 96 9.5.5 Message Flow in Support of Active Power Transfer Figure 39 - Example message flow for active power transfer SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 57 of 96 9.5.6 Message Flow in Support of Power Termination The sequence below describes the process for termination of power transfer when initiated from the EV (customer side) of the interface. Figure 40 - Message flow for EV initiated power transfer termination SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 58 of 96 9.5.7 Message Flow for Suspension of Power Transfer The message flow below is an example of the WEVSE indicating to the EV that the power transfer will be temporarily suspended. This may occur due to a grid DRS request or other reason. Figure 41 - Suspension of power transfer SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 59 of 96 10. SECURITY The use of TLS (with server authentication) between EVCC and SECC is optional. SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 60 of 96 11. XML SCHEMA The XML schema definitions types used in this standard can be distinguished as follows: • complex type use capitalized first letters • simple types use non-capitalized first letters. 11.1 V2G_CI_Beacon.xsd SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 61 of 96 11.2 V2G_CI_AppProtocol.xsd SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 62 of 96 11.3 V2G_CI_MsgBody.xsd SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 63 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 64 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 65 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 66 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 67 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 68 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 69 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 70 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 71 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 72 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 73 of 96 11.4 V2G_CI_MsgDataTypes.xsd SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 74 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 75 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 76 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 77 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 78 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 79 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 80 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 81 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 82 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 83 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 84 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 85 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 86 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 87 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 88 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 89 of 96 11.5 V2G_CI_MsgDef.xsd 11.6 V2G_CI_MsgHeader.xsd SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 90 of 96 11.7 xmldsig-core-schema.xsd xmlns:ds CDATA #FIXED \"http://www.w3.org/2000/09/xmldsig#\" > ]> SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 91 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 92 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 93 of 96 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 94 of 96 12.1 Marginal Indicia A change bar (l) located in the left margin is for the convenience of the user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in original publications, nor in documents that contain editorial changes only. 12.2 Patent Statement One or more patents may apply to one or more aspects of the standards or the entire standard. By publication of this standard, no position is taken with respect to the validity of this claim or of any patent rights in connection therewith. The patent holder(s) has, however, filed a statement of willingness to grant a license under these rights on reasonable and nondiscriminatory terms and conditions to applicants desiring to obtain such a license for the purpose of complying with the standard. Details may be obtained from SAE International at: http://www.sae.org/standardsdev/patents.htm. PREPARED BY THE SAE HYBRID - EV COMMITTEE SAE INTERNATIONAL J2847™-6 Issued AUG2015 APPENDIX A Page 95 of 96 Revision History Version No. 0.1 0.2 First rough draft for discussion Revision in response to feedback from SAE web call. • • • 0.3 WEVSE State model revised Messages added to support smart charging Other miscellaneous updates 06/25/2013 Description Date 03/18/2013 05/08/2013 Revision in response to feedback from SAE web call. • • • WEVSE State model revised Secondary Side (EV) State model added Other miscellaneous updates 0.4 Revision in response to feedback from SAE web call • • Added first set of sequence diagrams Started closer alignment with DC charging and IEC model 07/22/2013 0.5 Revision in response to feedback from SAE web call • • • • Added Target_Parameter_Indicator as proposed on call Added additional sequence diagrams Fixed inconsistencies in State Tables and State Diagrams Miscellaneous consistency corrections 09/09/2013 0.5a 0.6 0.7 0.8 0.9 0.95 0.97 Revisions to include Pairing and Alignment text from member contribution to SAE web call. Revision in response to October meeting discussion and comments via e-amil Revision 0.6 clean up based on December web-conference Inclusion of changes proposed at January meeting Inclusion of J2347/2 compatible message encoding Revision based on comments from May web-conference. This revision also attempts to further align with SAE J2847/2 (which in turn was aligned with DIN SPEC 70121). Revision based on comments from the group. 09/23/2013 12/10/2013 01/02/2014 02/19/2014 04/04/2014 05/23/2014 SAE INTERNATIONAL J2847™-6 Issued AUG2015 Page 96 of 96 0.98 Revision based on latest comments from the group. 03/10/2015 因篇幅问题不能全部显示，请点此查看更多更全内容