基于多绕组变压器的均衡电路占空比设计方法

Duty cycle design of battery equalizer based on multi-winding pulse transformer

针对电动汽车动力电池组在使用过程中出现的不一致现象,设计了一种基于多绕组脉冲变压器的电动汽车锂离子动力电池主动均衡电路。研究了多绕组变压器均衡系统的拓扑结构和工作原理,以及Top均衡和Bottom均衡两种控制策略,提出了基于最大占空比的脉冲变压器原、副边PWM设计方法,并建立了系统均衡电路的PSIM仿真模型。仿真和实验结果表明,在给定工况下,电池组均衡系统的原、副边绕组均实现了最大占空比控制和最高均衡电流工作,验证了均衡电路PWM占空比设计方法的正确性和有效性。

For the inequality phenomenon of battery packs in electric vehicles, a charge equalization converter using flyback multi-winding transformer in electric vehicle battery system was designed. The principal and circuit of the equalization system were particularly presented, as well as two balancing strategies named Top balancing and Bottom balancing. Taking account of the maximum work duty cy- cle, the way to design the system control PWM was described, and the PSIM simulation model of the equalization circuit was built. The simulation and experiment results demonstrate that both primary and secondary winding achieve the maximum control duty cycle and the peak work equalization current, so the effectiveness of the PWM design method for equalizer is verified.