Phase synchronization and current sharing strategy for multiple overlapped transmitters IPT system

Abstract

The overlapped transmitters IPT system with multi-inverters in parallel can effectively improve the power capacity. Compared with single transmitting coil, the overlapped transmitters IPT system can avoid the generation of circulating current. Aiming at the imbalanced current due to the deviation of resonant inductors and the delay of driving signal. A phase synchronization strategy based on PS-PWM is proposed. In this method, the phase difference of the resonant currents flows in the primary coils can be reduced. At the same time, the current sharing among different modules can be realized synchronously. A 2 kW equipment with two overlapped transmitters IPT System is established. The results showed that the methods can reduce the imbalanced current from 2 A to 0.2 A, and the phase difference of the resonant current is less than 5°. The efficiency of the whole modular IPT system can reach to 92.8% when the power is 2 kW.