Non-singular Fast Terminal Sliding Mode Control of Permanent Magnet Synchronous Linear Motor Based on Superhelix Algorithm

A novel non-singular fast terminal sliding mode control (NFTSMC) based on super torsional sliding mode Observer (STA-STO) was designed to solve the problems such as obvious buffeting, slow convergence time to reach surface of mucus and unknown disturbance in sliding mode control of permanent magnet synchronous linear motor (PMLSM). Frist, the non-singular fast terminal sliding mode surface is used to shorten the convergence time and eliminate the singularity problem. Then, a super helical synovial observer for sensor less position detection is introduced. Finally, the symbol function of the observer is expressed as a continuous function and get a new observer. Better than the traditional synovial observer, This observer significantly suppresses shaking.