Power stability optimization method of wireless power transfer system against wide misalignment

Wireless power transfer (WPT) system has been introduced to many applications. However, it allows very limited misalignment of the power receiver relative to the power transmitter, which is not suitable for some applications such as electric vehicle (EV) wireless charging. This paper presents methods to improve output stability over large misalignment from the perspective of compensation topology and magnetic coupler. For compensation topology, multi-level non-resonant topology is proposed and analyzed. By adjusting the component of the topology, output power can be modified. For magnetic coupler, solenoid type coil is applied with a quadrature pick-up in order to stabilize coupling coefficient. Experiment results show that proposed design methods can stabilize transmission power against a wide range of misalignment.