一种中压电力线通信阻抗匹配电路设计

Design of impedance matching circuit for MV power line communication

中压电力线信道特性复杂,其中阻抗失配会对通信质量产生重要的影响。分析了电容型相地耦合装置中耦合电容器和耦合变量器非理想参数引起的插入损耗。建立了匹配电路的模型,采用转移功率增益描述阻抗匹配的效果。以经典无源带通滤波器的结构为基础,保留耦合装置中非理想元件,基于非线性优化算法调整匹配网络的元件值,使得在50~500 k Hz范围转移功率增益的平均值达到最大。相关算例表明,该方法有效提高了整个频带的转移功率增益,达到了较好的匹配效果。所设计匹配电路结构简单,易于实现。

The channel characteristic of medium voltage power line is complex, in which the impedance mismatch will have an important impact on the quality of communication. The insertion loss is analyzed in the capacitive coupling device, which is caused by the non ideal parameters of the coupling capacitor and coupling transformer. A model of matching circuit is designed by using transfer power gain to describe the matching effect. Based on the structure of the classical passive bandpass filter and the parameter of non ideal element in coupling device, the component value of the matching network is adjusted by the nonlinear optimization algorithm. Finally, the average value of the transfer power gain reaches the maximum in the 50-500 kHz frequency range. Related examples show that the proposed method can effectively improve the transfer power gain of the whole frequency band and achieve a better matching effect. The structure of the matching circuit is simple and easy to implement. This work is supported by National Natural Science Foundation of China （No. 61204027） and Fundamental Research Funds for the Central Universities （No. 2015MS97）.