Safety considerations of wireless charger for electric vehicles — A review paper

Wireless power transmission is a promising technology which attracts attention in many fields and products. With mobile electronic products being prevalent, such as cellphones and PDAs, removing the power cord becomes a natural progression of achieving the ultimate mobility of the product. Wireless chargers for Electric Vehicles (EVs) would also be a convenient feature, avoiding any need to remember to plug in a power cord after parking the vehicle. Additional safety advantages may also be achieved due to eliminating exposed contacts. Nevertheless, wireless charging for EV is an application requiring high electrical power (up to hundreds of kilowatts) and larger area of wireless power transmission which increases electromagnetic field exposure. Thus, application of wireless charging to an EV requires a comprehensive analysis to ensure consumer safety. This paper focuses on the safety considerations of wireless charging for EVs, including potential electrical shock hazards, magnetic field exposure hazards, fire hazards, etc. It provides a historical background of wireless charging, particularly for EVs. It also reviews two potential technologies applicable to wireless charging of EVs. The concept of Hazard Based Safety Engineering (HBSE) is applied to the problem and UL's training's program is introduced.