An Improved Adaptive Full-Order Sliding-Mode Observer for Sensorless Control of High-Speed Permanent-Magnet Synchronous Motor

The development of advanced sensorless control of high-speed permanent-magnet synchronous motor (PMSM) has been an ever-increasing demand in modern drive fields. Herein, in this article, an improved adaptive full-order sliding-mode observer (FSMO) for sensorless control of high-speed PMSM is proposed to improve the estimation accuracy of rotor speed and position. A model-referenced adaptive electrical angular velocity & back electromotive force (back EMF) observer is established. The estimated electrical angular velocity is directly fed back to the FSMO, which highly reduces the noise in the FSMO & phase-locked loop (PLL) system and weakens the chattering of the back EMF waveform, so that the estimation accuracy of the PLL on rotor speed and position is significantly improved. Simulations and experiments compared with the conventional method are both carried out with a 3 kW high-speed PMSM. The experimental results demonstrate that the proposed FSMO has preferable speed and position estimation capabilities under various operating conditions, which verifies the feasibility and superiority of the proposed method.