Research on Rectifier Fault Diagnosis and Self-Protecting for Inductive Power Transfer System with Constant-Current Output

Inductive power transfer (IPT) technology is widely used because of its high convenience especially for charging of electric vehicles (EVs). It has remained a high failure rate in recent years due to the large number of semiconductor components they contain. In this paper, to address the problem that rectifier with constant-current output characteristics in the IPT cannot occur to open-circuit fault, a rectifier protected method based on SS type IPT system is designed. Firstly, the hazards and impacts on the system after a diode fault are analyzed. Then, a method for parameter design of protective devices have developed that does not affect the compensation parameter design of the original system, which maintain high efficiency operation after open-circuit fault, and a fault detection technology based on DC bias of the fault eigenvalue is proposed. This study solves the problem that the rectifier cannot be open-circuit faulted of the traditional IPT constant-current topology, which improves the reliability and safety of the system. Finally, experiments under different loads verify that the system rectifier can maintain an operating state with an efficiency of 91.78% after a diode open-circuit fault occurs, as well as the accuracy of the fault detection method