Research On Sensorless Control Of Interior Permanent Magnet Synchronous Motor In Full Speed Range

Interior permanent magnet synchronous motor is widely used in servo transmission systems with high control performance due to its high power factor and good speed regulation performance.Conventional permanent magnet synchronous motor speed control systems usually use mechanical position sensors,but the installation of mechanical sensors will bring some drawbacks to the speed control system,and due to some objective conditions,mechanical sensors cannot be installed in the speed control system.Therefore,it is necessary to use position sensorless control technology to extract speed and position information.This paper mainly studies the position sensorless control technology in the interior permanent magnet synchronous motor control system.Since the traditional sliding mode observer method uses a discontinuous symbol function as the switching function and a fixed sliding mode gain value,the chattering phenomenon is caused in the sliding mode observation system,which in turn makes the motor speed and rotor position estimation accuracy poor.To this end,this paper improves the sliding mode observer,replaces the traditional symbol function with the segmented inverse tangent function,and uses the adaptiveness of the fuzzy control to adjust the sliding mode gain value in real time according to the current observation error,and the gain boundary thickness is also It can be adaptively adjusted according to the motor speed;the traditional sliding mode observer method uses the back electromotive force observer method to estimate the motor speed and rotor position.This paper combines the improved sliding mode observer method with the phase-locked loop,using the phase-locked loop.High tracking characteristics to estimate speed and rotor position.The improved sliding mode observer method can effectively reduce the chattering phenomenon and improve the control precision.In the position sensorless control in the full-speed domain,the composite control method is adopted,which combines the pulse high-frequency voltage injection method suitable for the low-speed domain and the improved sliding mode observer method suitable for the high-speed domain to realize the complementary effect.The speed switching area is set in the motor full speed domain,and the two methods are weighted in the speed switching area.Considering that the estimation errors of the two control methods are different,the multi-objective optimization model is established with the minimum estimation error of the rotational speed and position,and the ant colony genetic algorithm is used to optimize the weighting coefficients of the weighting function in real time,so that the two methods smoothly switch between the rotation regions.Realize full speed domain control of permanent magnet synchronous motor.The simulation model of position sensorless control system is built on MATLAB platform.The simulation results show that the improved sliding mode observer method can effectively reduce system chattering and improve system control accuracy.The simulation results show that the improved sliding mode observer method can effectively reduce system chattering and improve system control accuracy.At the same time,in the whole speed domain operation of the motor,the weight coefficient of the switching region solved by the ant colony genetic algorithm can satisfy the smooth switching of the two control methods,and can effectively realize the full-speed high-precision control of the interior permanent magnet synchronous motor.