大功率交流电子负载的研究

Study of High Power AC Electronic Load

对大功率能量回馈式单相交流电子负载进行了深入研究,包括其主电路结构和控制方法。主电路采用AC/DC/AC结构,并用电压型PWM整流器构成其输入、输出变流器。给出了输入、输出变流器的控制策略。为了提高电子负载的动态响应性能,采用滞环电流控制技术作为控制方式,并采用数值算法计算参考电流。用PSCAD/EMTDC软件对所提出的电子负载进行了仿真并研制了试验样机。仿真和实验结果表明,所提出的电流算法及控制方法是有效的,实现了电子负载的恒定阻抗工作方式,输入端能准确模拟设定阻抗值且试验能量以单位功率因数回馈电网。

AC electronic load is used in testing of AC power source.In this paper an advanced high-power energy- feedback AC electronic load is studied,including its main circuit and control strategy.AC/DC/AC converter is adopted as the main topology structure,and the input and output converter all consists of voltage source PWM rectifier.The control strategies of input and output converter are given.To achieve good dynamic performance,hysteresis current control technology is adopted and the numerical algorithm is represented to calculate reference current.PSCAD/EMTDC is used to simulate the proposed electronic load and a prototype is researched and developed,Software simulation and experiment ALresults all show that the adopted algorithm and control strategy are effective.The fixed-impedance model of electronic load is implemented, in which model the input port of electronic load can accurately simulate the specified impedance and the testing energy can be fed back with unit power factor.