一种改进的永磁同步电机电流控制算法

An Improved Current Control Algorithm of Permanent Magnet Synchronous Motor

在机床永磁同步电机控制问题的研究中,电流环是永磁同步伺服驱动系统的关键环节。当电流环采用电流反馈解耦进行控制时,永磁同步电机在高速运行时易产生较大的电流跟踪误差,电流的动态响应变差。主要原因为电流反馈解耦控制对电流解耦不彻底导致电机转速对dq轴电流产生了耦合效应。为解决上述问题。在传统电流环P1调节器的基础上,提出了一种基于电压前馈解耦的电流控制算法代替电流反馈解耦控制。上述算法通过在电压指令中增加前馈补偿以消除耦合项的影响,进而消除电流跟踪误差,同时还具有李雅普诺夫意义上的稳定性。实验结果表明:改进算法实现了对dq轴电流的完全解耦,消除了电流跟踪误差,提高了电流控制性能。

The current loop is the key component of permanent magnet synchronous motor （PMSM） servo drive system. When the current feed back decoupling control method is used in current loop, the current tracking errors existed as the rotation speed is high, and the dynamic response of current becomes worse. By analyzing the control mechanism of the current feed back decoupling control method, the main reason is that the incompletely decoupling by current feed back decoupling control leds to the coupling on dq current by motor speed. In order to solve this problem, on the basis of traditional current PI regulator, a voltage feed forward decoupling control method which used d/q coupling terms in the voltage equations to compensate the command voltage of current PI regulator was pro posed to replace the current feed back decoupling control method, the d/q currents full decoupling was realized and the tracking errors were removed, meanwhile, the progressive stability of the system in the sense of Lyapunov were also proved. Experimental results verify the feasibility and effectiveness of the proposed method.