Sensorless Control of <scp>PMLSMs</scp> Based on Super Twisting Sliding Mode Algorithm

In this paper, a super‐twisting sliding‐mode controller phase‐locked loop (ST‐SMC‐PLL) with the super‐twisting sliding‐mode observer (ST‐SMO) technology is proposed for sensorless control of permanent magnet linear synchronous motors (PMLSMs). The serious chattering phenomenon is caused by the sign function in a conventional SMO, which will heavily degrade the position estimation accuracy and destroy the system stability. With the proposed ST‐SMO strategy, the sign function is placed in the integration stage, which will greatly suppress the sliding‐mode chattering. Moreover, the error transfer function of the conventional PLL is analyzed, which fails to balance the dynamic and steady‐state performance of the system. To overcome the shortcomings of the conventional PLL, the ST‐SMC‐PLL is proposed for extracting position information. The approach replaces the traditional PI controller with the ST‐SMC, which effectively improves the dynamic performance. At the meantime, the ST‐SMC‐PLL brings a smaller overshoot during the speed is changed. Finally, the steady‐state performance test and dynamic performance test are carried out on the dSPACE experimental platform. The experimental results show that compared with the conventional technique, the proposed method has a better control performance. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.