Design And Implementation Of Vector Control System For High-speed Permanent Magnet Synchronous Motor Based On Sliding Mode Observer

In recent years,high-speed permanent magnet synchronous motor has been widely used in modern industry and life because of its advantages.In order to overcome the disadvantages of the mechanical sensor which is easy to be disturbed by temperature,humidity,vibration and other factors.Among the sensorless control algorithms,the sliding mode observer has attracted much attention due to its advantages of simple physical implementation,good robustness and fast dynamic response.However,the observation results of sliding mode observer are easily disturbed by the sliding mode chattering.So,in order to obtain better control effect and meet the actual production demand,it is of great significance to optimize the sliding mode observer.In this thesis,the chattering suppression strategy is designed from two aspects.At first,a new switching function is designed according to the quasi sliding mode control theory.At the same time,the observer has the ability of adaptive change of sliding mode gain and boundary layer width,which can further effectively reduce the chattering.Secondly,considering that the estimated back EMF contains buffeting components,which will affect the observation results.By combining the PLL with the sliding mode observer,the speed position calculation based on the PLL is designed to reduce the chattering when calculate the speed and angel from the estimated back EMF accurately.In this thesis,the MATLAB / Simulink platform is used to simulate the improved control algorithm,and the control algorithm designed in this thesis are analyzed and verified.Finally,the hardware and software design of the sensorless vector control system fot high-speed PMSM with better chattering suppression effect is completed,and the performance index is tested.The test results show that:(1)the maximum speed of the control system reaches 48000 rpm,and the operation is stable with little fluctuation;(2)the observation accuracy of the new SMO is high,and the position estimation error is within ± 3 °,which achieves the expected design index.