基于DSP的伺服系统电流环的分析与设计

Analysis and Design on Current Control Loop of Servo System Based on DSP

分析了影响同步电动机矢量控制电流控制环动态特性的主要因素 ,指出同步电动机反电动势是其中最重要的干扰因素。针对通常采用的PI(比例 -积分 )电流调节器因工作频带的限制无法在较高转速时抑制反电动势的影响 ,提出了前馈补偿和变电流环增益的设计方法 ,并应用于基于数字信号处理器的矢量控制系统。给出了系统结构及软硬件设计方案。实验结果表明 ,该系统硬件简单 ,控制精度高 ,动态性能良好。

The main reasons affecting dynamic characteristic of current vector control loop system are analysed. It is pointed out that E.M.F(electromotiveforce) of synchronous motor is the most important interference, the general PI(proportion integration)current regulator does not retrain the effect of E.M.F at high speed because of limitation on its operation frequency width. So it is developed a method of current feedforward compensation and variable proportional gain control techniques which is applied to vector control system based on digital signal processor. The system structure and the method for designing the software and hardware are introduced. The experimental results show that the system has the advantages of compact structure and high control precision and dynamic characteristic.