基于改进快速幂次趋近律的永磁同步电机滑模控制

针对永磁同步电机(PMSM)滑模控制指数趋近律中趋近速度与抖振之间的矛盾问题,基于快速幂次趋近律提出一种幂次项系数自适应调节的新型趋近律。所提趋近律将系统状态引入幂次项系数中,实现了系统状态由较远处到滑模面附近的趋近过程中加入幂次项的作用,在保证幂次项特点的前提下,动态响应过程的收敛速度大大提高。负载转矩是滑模速度控制器中的一个扰动项,设计了带有幂次项的滑模观测器,将观测值作为转矩前馈补偿。仿真结果表明,与快速幂次趋近律相比,所提趋近律具有更快的收敛速度,负载观测器能准确跟踪负载变化,提升了系统抗扰性能。

Sliding Mode Control of Permanent Magnet Synchronous Motor Based on Improved Fast Power Reaching Law

There is a complex relationship between reaching speed and chattering in exponential reaching law of sliding mode control for permanent magnet synchronous motor (PMSM). Based on fast power reaching law, a new reaching law with adaptive adjustment of power coefficient is proposed. The proposed reaching law introduces the system state into the coefficient of power term, and the effect of adding power term in the reaching process of the system state from far to near the sliding surface is realized. On the premise of guaranteeing the characteristics of power term, the convergence speed of the dynamic response process is greatly improved. The load torque is a disturbance term in the sliding mode speed controller. A sliding mode observer with power term is designed, and the observed value is used as the torque feedforward compensation. The simulation results show that: compared with the fast power law, the proposed reaching law has faster convergence speed, and the load observer can accurately track the change of load and improve robustness of the system.