研制了一种电动车LLC 谐振充电电源系统． 该系统以STM32 为控制核心，采用数字化脉冲频率调制( PFM) 控制，选取满足电动车铅酸蓄电池充电电源要求的LLC 谐振主电路拓扑和4 阶段+ 正负脉冲充电方案． 试验结果表明: 该电源系统能够全程实现LLC谐振主电路的软开关状态，LLC 谐振主电路始终工作于原边MOSFET 功率开关管零电压开通和副边整流二极管零电流关断软开关状态，提高了电源转换效率; 结合电池充电曲线并使用4 阶段+ 正负脉冲充电方式，可以减少过充电及析气极化现象，保护电池，提高充电速度．

Proposed in this paper is a STM32-based LLC resonant charging power supply system for electric vehicles,which employs digital PFM ( Pulse Frequency Modulation) for the system control and adopts an LLC resonant topology as well as a four stages + positive and negative pulse charging scheme that meets the charging requirements of lead-acid battery.Test results demonstrate that ( 1) the proposed power supply system helps to implement the whole-course soft switching state of the main circuit of LLC resonant converters; ( 2) the main circuit of LLC resonant converters always operates in the primary-side MOSFET ZVS and the secondary-side rectifier diode ZCS softswitching state,which improves the power conversion efficiency; and ( 3) the combination of battery charging curves and four stages + positive and negative pulse charging scheme can reduce the overcharging as well as gassing polarization,protect the battery and increase the charging speed.