基于电容半桥谐振结构的无线能量传输系统

A wireless energy transmission system based on the half-bridge resonance structure of capacitors

为了简化传统感应耦合能量传输(inductively coupled power transfer,ICPT)系统的补偿网络结构,通过降低传统半桥变换器中的直流分压电容桥臂的电容量,使其与初级电感构成谐振回路,提出了一种基于改良半桥拓扑的ICPT系统.该系统具有以下特点:1)去除了初级补偿电容,简化了电路结构;2)母线电流为初级电感电流的一半,降低了电源容量要求,减少了导通损耗;3)开关管具有软开关通断的时间裕度,降低了开关管控制难度,减少了开关损耗和电应力.建立了系统数学模型并搭建出1 kW级的ICPT系统实验平台.实验结果表明,在耦合系数0.1~0.5、输出功率0.5~1.5 kW的范围内,系统效率都能维持在90%以上.

In this paper,we present an inductively coupled power transmission system based on an improved half-bridge topology.The system reduces the capacitances of the capacitor bridge arm in the traditional half-bridge converter to form a resonant capacitor.This resonant capacitor is combined with the primary inductor to form a resonant tank and accomplish primary series resonant compensation.The system is characterized as followed:the primary compensation capacitor is removed,simplifying the circuit structure.Next,the bus current is half of the primary current,reducing the power source capacity and conduction loss.Then,the switches are provided with soft switching time margin,reducing switch control difficulty and switching loss.In this paper,a mathematical model is established and a 1 kW prototype is fabricated.Experimental results show that the efficiency is above 90%when the coupling coefficient is in the range of 0.10.5,and output power in the range of 0.51.5 kW are maintained.