永磁同步电机的自适应模糊终端滑模速度控制

Speed control with adaptive fuzzy terminal sliding mode for permanent magnet synchronous motor

针对永磁同步电机驱动的连铸结晶器振动系统对电机速度的高精度要求,提出一种自适应模糊终端滑模速度跟踪控制方法。采用非奇异终端滑模,并结合趋近律设计速度控制器,不仅提高系统的收敛速度,而且避免传统终端滑模存在的奇异与抖振问题;考虑到负载转矩时变的情况,为增强系统抗负载扰动的能力,同时为消除控制律中的二阶导数项,运用自适应模糊算法对二阶导数项和含有负载转矩的未知函数进行估计。通过Lyapunov稳定性理论证明系统的稳定性。最后的仿真结果表明:该控制方法能够在负载干扰下实现快速准确的速度跟踪控制,控制量的抖振也得到抑制,系统对负载扰动具有较强的鲁棒性。

In the system of continuous casting mold oscillation driven by PMSM, the method of adaptive fuzzy terminal sliding mode control was proposed for the high precision requirement of motor speed tracking control. The speed controller was designed by using the non-singular terminal sliding mode and reaching law. And the proposed scheme can not only improve convergence rate, but also eliminate the problem of singular and chattering which exist in the traditional terminal sliding mode. In view of time-varying load torque, adaptive fuzzy algorithm was used to approximate second-order derivative term and unknown function with load torque, which can eliminate second-order derivative term in the control law and improve the ability of system to resist load disturbance. And the stability of system was also proved by the lyapunov stability theory. Finally, the simulation results show that this control method can achieve quick and accurate speed control with load disturbance, the chattering of control output is effectively attenuated, and the system has strong robustness for the load disturbance.