A Concept of Multiphase Dynamic Charging System with Constant Output Power for Electric Vehicles

Dynamic changing of Electric Vehicles (EV) is a new initiative aimed at increasing EV uptake. However, pulsating output power along driving direction is one of the most serious problems of such technology. This paper proposes a new configuration that ensures constant power with minimum power electronics requirements. The proposed system utilizes multiple primary windings that guarantee a homogeneous mutual magnetic flux for the receiver along the driving direction. This results in a constant induced voltage and hence constant output power to charge the EV's battery. Structure layout for primary transmitters including ferrite cores and windings is suggested and theoretical analysis is conducted to draw conditions of each winding's current phase and amplitude for achieving constant output power. The effectiveness of the proposed system is analytically demonstrated and experimentally verified using a 3-kW laboratory prototype with three-phase system.