Resonant Design of SP-Type Wireless Power Transfer Circuit Capable of Bidirectional Power Transfer

Abstract

In recent years, wireless power transfer has attracted attention in home appliances and electric vehicles. The SP method is typical for wireless power transfer based on magnetic field resonance coupling. However, because a capacitor is connected in parallel with the secondary inverter, reverse power transfer is not possible. This paper proposes an additional inductor circuit topology for reverse power transfer and present a circuit design method and presents a frequency control scheme based on parity-time symmetry theory.