This paper introduces an AC electronic load system for ground tests of aviation alternators. It has the characteristics of both good ripple rejection and following and is suitable for wide range of current and frequency characteristics of the ground tests. Its power circuit was made of a full-bridge AC / DC circuit and a simple energy consumption circuit. And single inductor was replaced by a LCL filter as the filter circuit to reduce high-frequency PWM harmonics introduced by ICBTs. Pseudo-derivative feedback control and optimal control were used in the control circuit to improve the stability and robustness of the system. Combined with input voltage feedforward control, the system can control the input current accurately. A 10kW AC electronic load has been studied with the PSIM soft-ware. The results showed that, in the circumstances that current and frequency fluctuated greatly, the system not only worked correctly, but also has small ripple and high accuracy.%研究航空发电机的地面测试系统优化问题,针对航空交流发电机地面测试中电流和频率变化范围宽的特点,影响跟踪性能.为保证负载系统同时具有较好的纹波抑制特性和基准跟随特性,设计了一种交流电子负载系统.主电路采用单相全桥AC/DC整流电路和简单耗能电路相结合的结构,并利用LCL滤波器代替传统的L滤波器作为功率滤波电路,使高频谐波分量大大减小.控制部分以建立的数学模型为基础,采用伪微分反馈控制和最优控制对控制系统结构和系统参数进行设计,保证了系统的稳定性和鲁棒性.通过与输入电压前馈控制相结合,系统能以较高的精度对输入电流进行控制.利用PSIM仿真软件平台对10kW的交流电子负载进行了仿真研究.结果表明,在电流和频率变化较大的情况下,系统不但可以正常工作,系统纹波小精度高,为优化设计提供了参考.
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