中文摘要：

提出一种三相电力电子负载的主电路拓扑,其中的并网变换器一方面将模拟负载变换器发出或吸收的有功功率高效的回馈电网,另一方面还具有一定的补偿被试电源所产生的无功及谐波的能力。应用一种新型的变步长自适应算法对被试电源输入电流谐波进行检测,同时,基于静止同步坐标系,设计一种重复控制器＋PI控制器串联的复合控制器对并网电流指令进行跟踪。仿真及实验证明,检测系统具有较好的检测精度及动态性能,应用该控制方法,系统对于并网电流指令具有较小的稳态跟踪误差以及较好的动态响应,同时,电网电流具有单位功率因数及较低的谐波电流,包含被试电源在内整机效率可达75%以上。

英文摘要：

A main circuit topology of three-phase power electronic load （PEL） was proposed. The grid connection converter should feedback the active power absorbed by simulation converter in order to maintain the DC bus voltage; on the other hand, it should have the ability to compensate the reactive and harmonic current produced by the device being tested. This paper applied variable step-size adaptive algorithm to detect the reactive and harmonic current of device being tested, at the same time, based on αβ coordinate system, a current control strategy, which was repetitive controller, and PI controller series connection was proposed. Simulations and experiments indicated the advantages of the harmonic detecting system and the current tracking system, and the efficiency of the whole system include the device being tested was higher than 75%.