Influence Analysis of Voltage Imbalance in Input-Series, Output-Parallel (ISOP) Multichannel IPT System

In order to solve the demand for efficient and stable low-voltage, high-power energy transmission capacity of electric vehicle (EV) fast charging, an ISOP-IPT system based on inductor-capacitor-capacitor series (LCC-S) compensation network is proposed. Firstly, the influence of compensation parameter inconsistency on the system is analyzed. On this basis, considering the resistance of coupler coils, the overall transmission efficiency of the system is analyzed. It is found that the voltage imbalance of the system will affect the working state of inverters, and then affect the stability of the system. The system transmission efficiency increases with the increase in mutual inductance. Moreover, the voltage imbalance caused by the inconsistency of compensation parameters and mutual inductance will reduce the transmission efficiency of the system. Finally, it is concluded that in the parameter design of the ISOP-IPT system, mutual inductance should be improved on the basis of ensuring the input voltage equalization of each channel so as to improve the transmission efficiency and working stability of the system. The experimental platform of a two-channel ISOP-IPT system is built and the maximum efficiency is 94.03%, which verifies the correctness of theoretical analysis.