Bench Testing Validation of Wireless Power Transfer up to 7.7kW Based on SAE J2954

Wireless Power Transfer (WPT) is presently being applied to consumer electronics in the low-power range and is planned to be commercialized in the high-power range for plug-in and electric vehicles in 2018. There are, however, many technology challenges remaining before widespread implementation of high-power WPT will occur. The SAE Vehicle Wireless Power and Alignment Taskforce published the Technical Information Report J2954 in 2016 to help harmonize the first phase of high-power WPT technology development. SAE J2954 adopts a performance-based approach to standardizing WPT by specifying ground and assembly coils to be used in a test stand (per Z-class) to validate performance, interoperability and safety. The main goal of this SAE J2954 bench testing campaign was to prove interoperability between WPT systems utilizing different coil magnetic topologies for SAE TIR J2954. The main challenge is that this type of testing had not been done before on such a scale with real automaker and supplier systems. A number of automakers, suppliers and government employees worked together to create a test plan, perform the testing and analyze the results. To evaluate the interoperability, performance, and EMC & EMF of this technology, a bench test program was created based on the SAE J2954 TIR, supported by the SAE WPT Taskforce along with the US Department of Energy's Idaho National Lab and TDK North America. The tests were conducted across two different power classes (between 3.7 kW to 7.7kW) and two different coil magnetic topologies (circular and double-D). This report describes the testing program and contains results from the different WPT systems. This testing validates the first stage of SAE J2954 standardization and proves that WPT is not only possible over an air gap of 250mm, but also interoperable over power classes and system designs with high efficiencies (many tests were above 90% AC to DC efficiency). The results of this report is being used as a basis for the Recommended Practice J2954 which is to be published in 2017.