At a recent standards meeting, carmakers, Tier 1 suppliers, and technology providers have reached agreement on key technical and procedural elements of the upcoming SAE Recommended Practice (RP) for Wireless Power Transfer (WPT) and automated parking alignment and charging. The goal of this standardization is to ensure interoperability among different brands of EVs and wireless charging stations.
Task force members agreed on specifications for the SAE J2954 Test Stations, which automakers will use to verify that their wireless charging systems will interoperate with systems and vehicles sold by other makers. The task force agreed that the WPT1 (3.7 kW) circular coil system and the WPT2 (7.7 kW) circular coil system will be included in the Test Stations.
SAE International has already performed bench testing of these systems to confirm that charging rates, efficiency, and emissions can meet regulatory guidelines and consumer expectations. The goal is to standardize key elements but at the same time keep the door open for future innovations in wireless automated charging.
In 2017, the task force will decide on other aspects of the standard, including standardization for wireless charging systems capable of WPT3 (11 kW) charge rates. Specifications of the SAE Test Station and procedures for charger validation will be defined in the SAE J2954 Recommended Practice, to be published later this year. The final SAE J2954 Standard is to be published in 2018, based on actual vehicle test data.
“Charging your vehicle should be as simple as parking it and walking away – and wireless charging with SAE J2954 enables that freedom and convenience to do this automatically,” says task force chair Jesse Schneider. “Automakers believe that wireless charging can greatly help to make electrified vehicles mainstream, and they have been active supporters of our standardization efforts.”