基于能量-相角的无线电能传输系统建模与验证

Modeling and verification of wireless power transmission system based on energy-phase angle

为了解决无线电能传输系统中电流和电压的变化频率较快且不能直接反映负载上的电压有效值的问题,采用基于能量-相角的建模法为全桥逆变器的无线电能传输系统建模,同时避免了相较于d-q分解法系统阶数较高的情况。首先分析了由全桥逆变器驱动的无线电能传输系统的等效电路模型,然后将能量和相角作为变量对等效电路模型进行小信号建模,接着将小信号模型在工作点附近线性化,得到系统的线性模型及其传递函数,最后开发全桥逆变器原型机并应用于无线电能传输系统。实验结果与小信号建模得到的幅相特性曲线在中低频段基本一致,在1 000 rad/s及以下频率情况下的吻合度达到90%,验证了建模方法和模型的准确性。

In order to solve the problem that in the wireless power transmission system,the frequency of current and voltage changes quickly,and cannot directly reflect the effective value of the voltage on the load,this paper adopts the energy-phase angle modeling method for the wireless power transmission system of full-bridge inverter,and avoids the higher order of the system compared with the d-q decomposition method.Firstly,the equivalent circuit model of the wireless power transmission system driven by the full-bridge inverter is analyzed,and the energy and phase angle are used as variables to build a small signal model for the equivalent circuit.Then,the small signal model is linearized near the operating point to obtain the linear model of the system and its transfer function.Finally,the prototype of the full-bridge inverter is developed and applied to the wireless power transmission system.The experimental results and the amplitude-phase characteristic curve obtained by the small signal modeling are basically the same in the middle and low frequency bands,and the agreement reached 90% at the frequencies of 1 000 rad/s and below,which verifies the accuracies of the modeling method and model.