整流模式下BWPT系统功率变换器的等效输入阻抗分析

由于功率变换器的等效负载阻抗对双向无线电能传输(BWPT)系统的特性分析有影响,因此对该等效负载阻抗进行计算有重要意义。文中首先建立了采用双向全桥功率变换器和LCC补偿的BWPT系统模型;然后,构建了工作于整流模式的功率变换器的等效电路,并对其整流工况进行了分析;进而,推导了双向功率变换器等效负载阻抗的计算方法;最后,搭建了试验平台,对建立的模型和提出的方法进行了验证。结果表明:工作于整流模式的双向功率变换器的等效负载阻抗包含电阻和电抗两部分,且它们的值与开关器件并联电容、补偿电感以及负载有关,所提出的方法能有效地对该等效阻抗进行计算,进而有助于准确地分析系统特性。

Equivalent Input Impedance Analysis of Power Converter for Bidirectional Wireless Power Transfer System in Rectification Mode

The equivalent load impedance of power converter has an influence on the characteristic analysis of bidirectional wireless power transfer(BWPT)system. So the calculation of equivalent load impedance is of great significance. Firstly, this paper builds a model of BWPT system with bidirectional power converters and LCC compensation networks. And the equivalent circuit of the power converter working in the rectification mode is established. Then, the equivalent circuit rectification operation is analyzed. Furthermore, the calculation method of equivalent load impedance of bidirectional power converters is derived. Finally, a test platform is developed to verify the proposed model and method. The result shows that, when the bidirectional power converter operates in the rectification mode, its equivalent impedance includes resistance and reactance parts, and both of them are related to the parallel capacitance of switch devices, compensation inductance and system load. The proposed method can effectively calculate the equivalent load impedance, which can contribute to accurately analyze the system characteristics.