Research On Speed Sensorless Control Of High Speed Permanent Magnet Synchronous Motor Based On SiC Driver

High Speed Permanent Magnet Synchronous Motor(HSPMSM)has broad application prospects in fields such as mold processing and high-speed air compressors due to its small size,high power density,and high efficiency.It also puts forward higher requirements for the performance of motor drive systems.SiC drivers can achieve higher switching frequencies and lower switching losses in the application of HSPMSM,thereby improving system power density and efficiency.Considering the small size and limited axial space of HSPMSM,it is difficult to install mechanical speed sensors.Therefore,this article conducts research on the speed sensorless control of HSPMSM based on SiC drivers.Based on the mathematical model of HSPMSM and the sliding mode control theory,a discretization model of sliding mode observer in d-q coordinate system is constructed.In order to overcome the limitations of the saturation function sliding mode observer in chattering suppression,a speed sensorless control strategy of the sliding mode observer based on supertwisting algorithm is studied.Through theoretical derivation and system stability analysis,an adaptive sliding mode factor algorithm with sliding mode coefficients adjusted online according to the speed change is designed.The simulation verifies that this method can suppress chattering effectively in a wide speed range,improve the estimation accuracy of speed sensorless control system,and simplify the parameter adjustment process compared with the sliding mode observer based on saturation function.Due to the high base frequency of HSPMSM,in order to ensure its stable operation at high speed,the hardware platform of SiC driver is designed to achieve high frequency carrier PWM control.At the same time,a controller with STM32H750 as the core is designed to improve the operational performance of HSPMSM under high switching frequency.The calculation of main power,signal conditioning circuit selection and the overall circuit design in hardware platform are described in detail.Finally,the proposed speed sensorless control strategy is validated on the hardware platform.The experimental results show the effectiveness and feasibility of the method.