NSK has developed the third generation of its in-wheel motor, the world’s first design of its type to feature a complete package comprising motor, inverter and wireless charging unit.
The innovative wireless in-wheel motor (W-IWM) for the electric vehicle (EV) market is capable of charging from coils embedded in the road, while in motion. Development of the latest unit was conducted jointly by a research group comprising NSK, the Fujimoto Laboratory at the University of Tokyo’s Graduate School of Frontier Sciences, Bridgestone Corporation, ROHM and Toyo Electric Mfg.
Reducing CO2 emissions in order to achieve a low-carbon society is a global challenge that calls strongly for reductions in automobile emissions, hence the growing development and take-up of EVs.
Some concerns have been raised regarding the convenience of stationary EV charging and the amount of resources required to produce large amounts of battery cells. Efficient running with a minimal amount of battery cells is therefore required for the sustainable spread of EVs. As a result, wireless charging while in motion has been capturing the attention of OEMs keen on realising EVs with small batteries.
The third-generation W-IWM developed by the joint research group has vastly improved in-motion charging capability, motor performance and ease of mounting, bringing together the features required for practical application.
The W-IWM has been developed so that the in-motion wireless power receiver circuit, as well as the EV’s driving mechanism fit entirely inside the wheel.
While the research group is currently in the process of testing and evaluating the third-generation W-IWM, the aim is to enter the verification phase for the real-world testing of an in-motion wireless charging system by 2025.
