基于三级式可扩展多模块并联架构的低压大电流高距径比无线电能传输系统

Low-voltage,High-current and High Distance-diameter Ratio Wireless Power Transfer System Based on Three-stage Scalable Multi-module Parallel Architecture

在低压大电流高距径比磁谐振式无线供电场合,由于传输线圈间的耦合系数很小,因此功率器件和谐振元件的电流很大,导致系统损耗大,难以优化设计。为此,文中提出一种三级式可扩展多模块并联无线电能传输系统架构,利用基波分析法对双模块并联系统建模并分析其传输特性。为提升系统效率,对比3种输出级结构及其控制策略并遴选出一种最优拓扑。进一步地,提出线圈级具体参数设计方法以减小电压电流应力并实现输入级软开关。最后搭建一台距径比为1(30 cm/30 cm)的1 kW原理样机验证理论分析,对比3种不同输出级拓扑的性能。实验结果表明,系统最高效率可达75.2%。

In high-power and high distance-diameter(d-D)ratio wireless power transfer(WPT) applications,it is very difficult to design the power switches and resonant components due to high current caused by quite low coupling coefficient between transmission coils.In this paper,a novel three-stage scalable multi-module parallel WPT architecture is proposed for low voltage and high current applications.Then,the transfer characteristics are presented through the model of a dual-module parallel system by the fundamental harmonic analysis method.Furthermore,three output-stage structures and the corresponding control schemes are compared to optimize the system performance.Moreover,a parameter design method for the coil-stage is proposed to reduce the voltage and current stress and realize zero voltage switching(ZVS) in the input-stage.Finally,a 1 kW MCR WPT prototype with the d-D ratio of 1(30 cm/30 cm) is built and the experiments on three different output-stage topologies are carried out to compare their performance,and the maximum efficiency is 75.2%.