采用西门子S7-1500可编程控制器和Sinamics S120变频器设计了机器人用伺服系统性能测试加载系统。介绍了性能测试系统的组成以及加载系统的软硬件设计方法。给出了加载闭环控制系统的建模方法，设计了转矩比例积分控制器和转矩微分负反馈控制器，以消除加载转矩静差和抑制转矩超调。实际应用结果表明，该系统各项性能指标均满足设计要求。

A loading system for performance test of servo systems in robots is designed by using a programmable logic controller S7-1500 and a variable frequency converter Sinamics S120. The compositions of performance test system, hardware and software designs of the loading system are presented. The close-loop control of loading system was modeled, and the torque proportional-integral controller and torque differential negative feedback controller are introduced to eliminate static torque errors and suppress torque overshoots. The practical application results show that the system performance indicators can meet design requirements.