Closed-loop control with harmonic based phase-shift control for inductively coupled power transfer system

The output power regulation and transfer efficiency are key issues in inductively coupled power transfer system (ICPT) systems. The harmonic based phase shift control (HPSC) is an effective method to improve system efficiency. However, due to the high frequency and harmonic components of the inverter output current within this method, general closed-loop control is not suitable. Meanwhile, in inductively coupled power transfer system of contactless power supply (CPS) system for rail transit, the output voltage and current on board cannot be sent directly to the controller by cable on ground. This paper propose a novel control method by using the inverter average current and secondary load voltage to adjust transferred power with lower switching losses. It is especially effective for light load condition. Both the simulation and experimental results verify effectiveness of the proposed control method.