Research And Implementation Of PMSM Fault-tolernt Control In Hall Position Sensor Failure

Permanent Magnet Synchronous Motor(PMSM)is widely used in industrial automation due to its good power density and speed regulation performance.Due to the influence of the external environment and the limitation of the life of the components,the Hall position sensor will inevitably fail,resulting in the equipment unable to operate normally and even causing human life danger.Therefore,it is of great significance to study the fault-tolerant control of Hall position sensor in the fault state.In order to solve the problem of system operation in the case of Hall sensor failure,In this paper,the Hall sensor fault detection and speed observation methods are studied,combined with sensorless control technology,a fault-tolerant control strategy within the full-speed range of the motor is proposed,and a fault-tolerant control algorithm is implemented.the main research contents are as follows:1.Hall sensor fault detection: According to the output rule of the PMSM Hall position sensor signal,the pulse sequence of the Hall sensor in the fault state is studied,and the software is been used to compare the current Hall pulse sequence with the Hall fault pulse sequence to realize the Hall fault detection.2.Fault-tolerant control scheme: the PMSM sensorless algorithm is beenused as the fault-tolerant control scheme under the fault condition of the Hall position sensor.Combined with the saturation salient polarity of the motor,the pulse vibration high frequency voltage injection method is been used to realize the rotor position estimation in the range of static and low speed under the fault state of the Hall sensor.Aiming at the problem of large amount of chattering in the traditional sliding mode observer,a new sliding mode observer combining variable gain coefficient and sigmoid switching function is been studied to realize rotor position and speed observation in the middle and high-speed range.3.Mode switching strategy: Considering the chattering problem in the process of switching between Hall sensor mode and sensorless mode,the function interval of two sensorless algorithms is quantified by the weighting function,combined with the linear electrical angle compensation strategy to realize the Hall sensor mode and sensorless switching of modes.4.Verification of fault-tolerant control algorithm: In order to verify the fault detection,mode switching and speed observation performance of the sensorless algorithm when the Hall sensor is faulty.A PMSM fault-tolerant control simulation model was been built to simulate the mode switching and rotor position estimation in the low-speed and medium-high speed range.Finally,the fault-tolerant control experiment was carried out on the road brake motor control experimental platform.The experimental results show that the PMSM fault-tolerant control algorithm can detect the fault signal when the Hall sensor is faulty,and achieves a smooth switch between the Hall sensor mode and the sensorless mode.