This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Wireless Power Transfer for Light-Duty Plug-in/Electric Vehicles and Alignment Methodology
- Ground Vehicle Standard
- J2954_201904
- Revised
Downloadable datasets available
Annotation ability available
Sector:
Issuing Committee:
Language:
English
Scope
The Recommended Practice SAE J2954 establishes an industry-wide specification that defines acceptable criteria for interoperability, electromagnetic compatibility, EMF, minimum performance, safety, and testing for wireless charging of light-duty electric and plug-in electric vehicles. The specification defines various charging levels that are based on the levels defined for SAE J1772 conductive AC charge levels 1, 2, and 3, with some variations. A standard for wireless power transfer (WPT) based on these charge levels enables selection of a charging rate based on vehicle requirements, thus allowing for better vehicle packaging and ease of customer use. The specification supports home (private) charging and public wireless charging.
In the near term, vehicles that are able to be charged wirelessly under Recommended Practice SAE J2954 should also be able to be charged by SAE J1772 plug-in chargers.
This Recommended Practice is planned to be standardized after the 2018 timeframe after receiving vehicle data. The contents, including frequency, parameters, specifications, procedures, and other contents of this Recommended Practice, are to be re-evaluated at that time to allow for additional developments and future innovations.
SAE Recommended Practice SAE J2954 addresses unidirectional charging, from grid to vehicle; bidirectional energy transfer may be evaluated for a future standard. This Recommended Practice is intended to be used in stationary applications (charging while vehicle is not in motion); dynamic applications may be considered in the future. In this version only above-ground (surface mounted) installations are covered; flush mounted installations have been discussed but are not yet ready for inclusion.
SAE Recommended Practice J2954 is meant to be used for interoperability, performance and emissions testing, where a single standard coil-set has been chosen for the WPT power class 1, 2 and 3, up to 11 kW per Z-classes (1 through 3) using circular topology. This SAE J2954 Test Station is meant to provide a baseline where compatibility with the content of the Recommended Practices is to be demonstrated.
The future standard, will use this performance based SAE J2954 standard Test Station to establish a uniform way to demonstrate design for both the electrified vehicle (VA) and WEVSE (GA) components safety, interoperability, performance, and EM emissions through testing. The goal is to have a common methodology to validate WPT and alignment, production designs between different power classes, and topologies for both the vehicle and infrastructure.
Rationale
Electrified powertrains, specifically battery electric and plug-in electric (BEV/PHEV) vehicles are projected internationally to become more prevalent in production due to environmental factors (such as CO2 emissions), regulations (such as the Greenhouse Gas and the California ZEV Mandate), and the increasing price of fossil fuels. The main benefits of electrified powertrains are eliminating or significantly reducing local emissions while increasing the overall well-to-wheels efficiency. In addition, autonomous vehicles are soon to be more commonplace to allow more convenient and safer transportation, especially in traffic settings and long-distance driving.
Standardized wireless power transfer (WPT) (wireless charging) allows the BEV/PHEV customer an automated and more convenient alternative to plug-in (conductive) charging. Essentially, the customer simply needs to park into a SAE J2954 compatible parking space in order to charge the vehicle. WPT offers the additional advantage to autonomous vehicles enabling autonomous parking with alignment assistance and automated charging (in all weather conditions, such as rain or snow).
It is essential that data-based standards are used as a basis for commercialization of this technology. The SAE J2954 TF has documented the lessons learned from the first stage of testing with real OEM systems. The SAE J2954 Recommended Practice will be an evolution of the TIR J2954 based on interoperability data.
Recommended Content
Ground Vehicle Standard | Wireless Power Transfer for Light-Duty Plug-in/Electric Vehicles and Alignment Methodology |
Ground Vehicle Standard | Security for Plug-In Electric Vehicle Communications |
Ground Vehicle Standard | Recommended Practice for the Design and Test of Hybrid Electric and Electric Trucks and Buses for Electrical Safety |
Topic
Data Sets - Support Documents
Title | Description | Download |
---|---|---|
Unnamed Dataset 1 | ||
Unnamed Dataset 2 | ||
Unnamed Dataset 3 | ||
Unnamed Dataset 4 | ||
Unnamed Dataset 5 | ||
Unnamed Dataset 6 | ||
Unnamed Dataset 7 | ||
Unnamed Dataset 8 | ||
Table 1 | WPT power classifications for LD vehicles | |
Table 2 | Interoperability by power class | |
Table 3 | Specification of the Z-classes | |
Table 4 | Compatibility between Z-classes of product GAs and VAs | |
Table 6 | Positioning tolerance requirements for Test Station VAs and product VAs | |
Table 7 | Component-level EMC - off-board components | |
Unnamed Dataset 15 | ||
Table 8 | EMF exposure standard, Reference Levels | |
Unnamed Dataset 17 | ||
Table 13 | Reference EMF exposure measurement standards | |
Table 14 | Example worksheet for worst-case operating condition search | |
Table 15 | Touch current measurement points | |
Table 16 | Coupler configurations for touch current measurement | |
Table 17 | Combined EMF and pacemaker limits for laboratory use | |
Table 18 | Measurements of fields | |
Table 19 | “Natural offset” (x_0) for the systems as described in the appendices of this document | |
Table 20 | Maximum rotational offsets | |
Table 21 | Sample efficiency test form | |
Table 22 | Table of test objects | |
Table A1 | Inductance | |
Table A2 | Inductance | |
Table A3 | Inductance | |
Table A4 | Typical Ferrite Properties | |
Table A5 | Secondary coil inductance L and impedance matching values | |
Table A6 | Typical ferrite properties | |
Table A7 | Secondary coil inductance L and impedance matching values | |
Table A8 | Typical ferrite properties | |
Table A9 | Secondary coil inductance L and impedance matching values | |
Table A10 | Typical ferrite properties | |
Table A12 | Secondary coil inductance L | |
Table A13 | Typical ferrite properties | |
Table A15 | Secondary coil inductance L | |
Table A16 | Typical ferrite properties | |
Table A18 | Secondary coil inductance L | |
Table B2 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table B4 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table B6 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table B8 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table B10 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table B12 | Secondary coil inductance L2 and secondary tuning capacitor C | |
Table C1 | Maximum values of currents | |
Table C2 | Primary coil inductance L1 depending on the Z-class | |
Table C3 | Coupling k between primary and secondary coil depending on the Z-class | |
Table C4 | Typical Ferrite Properties | |
Table C5 | Table of values | |
Table C6 | Primary coil inductance L depending on the Z-class | |
Table C7 | Maximum currents in the Test Station Universal GA | |
Table C8 | Coupling k between primary and secondary coil depending on the Z-class | |
Table D2 | Primary coil inductance L1 depending on the Z-class | |
Table D3 | Coupling k between primary and secondary coil depending on the Z-class | |
Table D7 | Primary coil inductance L1 depending on the Z-class | |
Table D8 | Coupling k between primary and secondary coil depending on the Z-class | |
Unnamed Dataset 61 | ||
Table F1 | Fundamental mutual inductance M_(0,R) values for Z1 (in [µH]) | |
Table F2 | Fundamental mutual inductance M_(0,R) values for Z2 (values in [µH]) | |
Table F3 | Fundamental mutual inductance M_(0,R) values for Z3 (values in [µH]) | |
Table F4 | Secondary impedance Z for fixed power level and varying output voltage U . Z is independent of any coil geometry, but varies for different VA-electronic configurations. VA-electronic typically differs for different Z-classes. | |
Table F5 | Calculation of Z impedance for fixed power level and varying output voltage U . The Z -values are transferred from . All combinations of each Z -value and each magnetic transformer tuple must be used to determine Z . | |
Unnamed Dataset 67 | ||
Table F6 | Calculation of Z impedance including tolerance factor for fixed power level and varying output voltage U . The tolerance factor is applied to the Z -values transferred from and the magnetic parameters. All combinations of each Z -value and each magnetic transformer tuple must be used to determine Z . | |
Unnamed Dataset 69 | ||
Unnamed Dataset 70 | ||
Unnamed Dataset 71 | ||
Unnamed Dataset 72 | ||
Unnamed Dataset 73 | ||
Table F7 | Z1 electric interoperability conformance testing | |
Table F8 | Z2 electric interoperability conformance testing | |
Table F9 | Z3 electric interoperability conformance testing | |
Table I1 | Approximate impact on voltage-amperage of varying k based on design and chosen operation | |
Table I2 | Approximate pad losses assuming, with two values of and variations in primary and secondary operating | |
Unnamed Dataset 79 | ||
Table L1 | ||
Table L2 |
Issuing Committee
The Hybrid Technical Standards Committee reports to the Powertrain Systems Group of the Motor Vehicle Council. The Committee is responsible for developing and maintaining SAE Standards, Recommended Practices, and Information Reports related to the field of hybrid vehicle technology. The following topics are within the scope of this committee's work: safety aspects of hybrid systems in vehicles, test procedures to establish the performance of hybrid systems and components, nomenclature, as well as vehicle interface and serviceability requirements Participants in the SAE Hybrid Technical Standards Committee include OEMs, suppliers, consulting firms, government, and other interested parties.
Reference
Number | Title |
---|
* Redlines comparisons are available for those standards
listed in the Revision History that contain a radio button. A
redline comparison of the current version against a revision is
accomplished by selecting the radio button next to the standard and
then selecting 'compare'. At this time, Redline versions only exist
for some AMS standards. SAE will continue to add redline versioning
with ongoing updates to SAE MOBILUS.