可实现接收端轻量化和抗短路的无线充电系统LCC-S补偿参数配置方法

Compensation Parameter Configuration Method for Wireless Charging System With LCC-S Topology to Achieve a Lightweight Receiver and Short-circuit Tolerance

功率等级提升与轻量化是电动汽车无线充电系统(wireless charging system,WCS)的重要发展方向,如何在轻量化设计基础上兼顾极端工况耐受能力,则是当前面临的关键问题之一。文中基于大功率WCS传统模块化并联结构,提出一种接收端失谐的补偿参数配置方法;分析采用该配置方法后WCS能量传输特性,揭示其具有直流输出波动平抑和抗短路能力;进一步从优化输出功率和传输效率角度,制定具有抗短路能力的大功率轻量化WCS整体设计流程;研制一台3kW无线充电原理样机,对上述方法正确性和设计流程有效性进行实验验证。结果表明,与采用传统LCC-S拓扑的WCS相比,改进后系统效率可达95.7%,直流输出脉动减小近80%,系统滤波电容容量可减小约90%,接收端短路电流为额定值1.4倍左右,具有较强抗短路能力。

Power level improvement and lightweight are inevitable trends of electric vehicle wireless charging system(WCS).It is a critical issue that the lightweight design of WCS should consider the tolerance of extreme operation conditions.Based on the traditional parallel modular structure of high-power WCS,a compensation parameter configuration method of detuning receiver is proposed.The paper analyzes the energy transmission characteristics of this method,and it reveals that the method can suppress DC output fluctuation and has the ability of short-circuit tolerance.Furthermore,the overall design process of the high-power lightweight WCS with short-circuit tolerance is presented in order to optimize the output power and transmission efficiency.To verify the correctness of the proposed method and the effectiveness of the design process,a 3kW WCS prototype is designed and manufactured.The experimental results show that the improved WCS system can reach the efficiency of 95.7%,and its DC output pulsation and filter capacitance are reduced by nearly 80%and by about 90%,respectively,in comparison to those of the traditional WCS with LCC-S topology.Moreover,the short-circuit current of receiver is about 1.4 times the rated value,which shows a relatively strong short-circuit tolerance.