Nonsingular Terminal Sliding Mode Control for PMLSM Based on Disturbance Observer

In order to achieve high precision speed control of the permanent magnet linear synchronous motor (PMLSM), this paper proposed a nonsingular terminal sliding mode control (NTSMC) with nonlinear disturbance observer (NDO). First, the model of PMLSM based on field oriented control (FOC) is given. Then, a NTSMC is proposed via backstepping. The controller can make the states reach the manifold in finite time. With the motor moving, it will be disturbed by friction and load, which will affect the system stability. Therefor, a NDO is introduced to estimate the unknown disturbance. The observed value is dynamically compensated to the NTSMC, which improves the control precision of the PMLSM system. Finally, the proposed algorithm is applied in dSPACE compared with PI, the experimental results show the proposed controller has better dynamic and static performance.