Research on Battery Module Equalization Strategy for Wireless Power Transfer System

As an emerging energy transmission technology, wireless power transfer (WPT) can supply power to various devices without physical contact, and solve the problems of interface aging and poor safety performance in wired transmission, which has broad application prospects. At present, many scholars have conducted in-depth research on WPT technology and active equalization of battery modules, but few people have applied WPT technology to the active equalization system for battery modules of electric vehicles (EVs). This paper studies and analyzes the principle of magnetically coupled resonant wireless power transfer and the phase-shifting synchronous control technology of double H-bridge converters. Based on the new LCC-S-S-LCC compensation topology, a new model suitable for the active working voltage equalization for battery modules of EVs is designed and a new control strategy of the equalization is innovatively proposed. Finally, a set of simulation platform for the equalization system of battery modules based on LCC-S-S-LCC topology with a frequency of 68kHz and a coupling mutual inductance of 8.1μH was built in MATLAB/Simulink. The simulation results show that the combination of the designed topology model and control strategy can effectively equalize the equalization system for battery modules to achieve the preset equalization effect.