Industry agrees on wireless charging standard for cars
“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 Jesse Schneider, chairman of the taskforce. Wireless charging is regarded across the automotive industry as a pivotal element to make electrified vehicles mainstream. Therefore, the agreement is “a major step forward for the industry”, as Schneider put it.
In detail, the taskforce members have agreed on specifications for the SAE J2954 Test Stations, which automakers will use as a basis to develop their wireless charging systems, and to verify interoperability of charging systems and vehicles regardless of manufacturer and model. The taskforce agreed that the WPT1 (3.7 kW) circular coil system and the WPT2 (7.7 kW) circular coil system will be in the Test Stations used to test products developed by car makers, Tier 1 suppliers, and charging infrastructure suppliers to confirm SAE J2954 compatibility. These wireless charging systems charge at the same rate as existing Level 1 and Level 2 wired chargers.
Earlier in 2016, SAE International performed bench testing of these systems at the US Department of Energy’s Idaho National Laboratory and TDK to confirm that charging rates, efficiency, and emissions meet regulatory guidelines and consumer expectations. The testing results validated interoperability between different coils (both circular and DD). This enabled the RP SAE J2954 test station to have more freedom to prove interoperability with other topologies with newly established interoperability criteria. The goal is to standardize key elements but at the same time keep the door open for future innovation.
The consensus reached by the taskforce gives carmakers the freedom to design the components for their own vehicles based on their preference for coil topology and power electronics design, while assuring the interoperability of their systems with the charging source.
In 2017, the taskforce plans to decide on other aspects of the standard, including standardization for wireless charging systems capable of WPT3 (11 kW) charge rates. The final SAE J2954 Standard is expected to be published in 2018 based on actual vehicle test data.
More information: https://standards.sae.org/wip/j2954/