Position Sensorless Control of PMSM Based on Double Sliding Mode Variable Structure

The sensorless control of permanent magnet synchronous motor with high performance is a research hotspot at present. A variable structure control method based on double sliding mode is proposed to improve the position detection and regulator. The position sensor and speed PI regulator in traditional control mode are replaced by sliding mode observer (SMO) and sliding mode controller (SMC) respectively. Using SMO to estimate rotor speed and position, SMC improves system stability and responsiveness. Meanwhile, the continuous smooth hyperbolic tangent function is used to replace the sign function in the sliding mode control to weaken the chattering caused by the sliding mode control. The simulation and experimental results show that the dual sliding mode variable structure control has better dynamic performance and stronger stability.