Update: SAE J2954 wireless charging validation to 11kW, Recommended Practice to enable autonomous vehicle parking and charging in 2017
At the SAE 2017 Hybrid & Electric Vehicle Technologies Symposium last week, an overview of the plans for testing to validate power levels up to WPT 3, (11kW) for SAE J2954TM were shown along with a preview of the technology to be standardized in the upcoming Recommended Practice. (Earlier post.)
The SAE Wireless Power Transfer (WPT) and Alignment team has been working with the Idaho National Lab and US Department of Energy (DOE) regarding testing for the validation of WPT 1-2 (3.7-7.7kW) in 2016. In 2017, bench testing for both matched and interoperable assemblies to validate the WPT 3 (11 kW) power level under both ideal conditions and maximum offset is being planned.
Eight automakers (OEMs) have committed to work with the SAE J2954 Taskforce to provide vehicles for collaborative WPT testing planned to begin in third quarter 2017, scheduled complete in 2018. This SAE vehicle and infrastructure test is being discussed with the US DOE and its national labs to cover both wireless charging and vehicle alignment.
The SAE Wireless Power Transfer (WPT) and Alignment Taskforce is underway with defining vehicle and infrastructure hardware and software to be able to automatically park and charge autonomous vehicles.
The upcoming SAE J2954 Recommended Practice will enable a seamless, automated standard methodology to charge for individual vehicles to fleets of autonomous vehicles and their infrastructures. All of this with a specification to charge with high efficiencies over an air gap of 250mm (10 inches).—Jesse Schneider, chair of the SAE J2954 task force
For the infrastructure side, a common location for the wireless charging ground assembly—in the parking lot—will be determined in 2017. In the published SAE TIR J2954, alignment is done through magnetic field triangulation using either the existing charging coils or an auxiliary antenna. SAE J2954 is planning to make a decision regarding alignment in 2017 as a basis for all infrastructure ground assemblies.
The SAE Communications Taskforce is assisting the Wireless Charging with an ecosystem for wireless communications, to allow a seamless vehicle to wireless infrastructure and later vehicle to ground assembly. SAE is utilizing IEEE 802.11(n) as a basis for this communications, which is similar to DSRC (or IEEE802.11p). The goal is that the vehicle navigation system can first locate an available wireless charging parking spot, lead you to a wireless charging point and SAE J2954 would help align your car in the parking spot, and finally wirelessly charge. As a concept, payment could be also automated through the same communications hub with no interaction required from the customer except pre-authorizing the payment.
The goal is to provide one minimum methodology for the vehicle and ground assembly to assist in alignment the vehicle at SAE J2954 stations. This would assist for both manual (self-parking) and autonomous (automated) parking. Wireless Charging is the only way for autonomous vehicles to be able to park and charge themselves automatically (in all weather conditions).—Jesse Schneider
The SAE Wireless Power Transfer (WPT) and Alignment Taskforce is working to ensure that electric vehicle wireless power transfer systems from diverse manufacturers will interoperate seamlessly with each other to prepare for commercialization in 2020. The published SAE TIR (Technical Information Report) J2954 provides guidance to ensure performance and safety of Wireless Power Transfer (WPT) Systems from one vendor will interoperate with another vendor with high efficiency. For this, the team has solidified a specification for a testing station.
The SAE WPT task force has two more milestones to complete: a J2954 Recommended Practice (Technical Specification) in 2017 to provide basis for finalizing bench and vehicle testing. In 2018, the vehicle and bench testing data will be used to finalize the Standard J2954 to be a basis for commercialization in 2020 for light duty chargers, stated Schneider.
Further, SAE International has made a proposal to Electrify America to start a build-out of multiple hundreds of Light Duty Wireless Chargers starting in 2019 in public locations in California and ZEV states in three stages. The goal is to use the SAE J2954 as a basis for infrastructure hardware and software and support the vehicle commercialization.
With any new technology, the cliché of the chicken-and-egg is always asked, who will bring the product to market first, the vehicle or the infrastructure? In this case, SAE International made a proposal to Electrify America for the first buildout of wireless power transfer according to SAE J2954.—Jesse Schneider
The first phase of the SAE International Proposal to Electrify America is for light duty vehicles infrastructure to WPT 3 (11kW) in public locations (for example in malls, workplaces, condominiums, etc). Another phase is to enable an infrastructure for autonomous fleets of vehicles (such as taxis,etc.) to be able to autonomously charge. At a later phase, SAE International is proposing a Heavy Duty Chargers infrastructure buildup based on SAE J2954/2 (for example public transit agency, truck stops for anti-idling, etc.).
An important outcome of this first infrastructure build up would be to be able to provide significant statistical data to evaluate the benefits for wireless charging according to SAE J2954. For instance, independent organizations or government organizations would be able to quantify how much wireless charging may increase the eVMT (electric Vehicle Miles Traveled) for wireless charging (inductive charging) vs. plug-in (conductive charging) electric vehicles which has the potential to make a significant impact to reduce CO2 especially in PHEVs.