Research On Speed ??Sensorless Control Strategy Of Permanent Magnet Synchronous Motor

Permanent magnet synchronous motor(PMSM)is widely used in new energy field and advanced industry due to its advantages of high power,large starting torque and reliable operation.However,the traditional permanent magnet synchronous motor is equipped with a position sensor,which brings a lot of interference to its precise operation control due to its own design factors.Therefore,based on fuzzy control theory,model reference adaptive control and sliding mode control method,sensorless compound control was studied,and an improved model reference adaptive sliding mode sensorless compound control scheme was proposed.Firstly,this paper introduces three kinds of structure classification of PMSM,and the mathematical models of PMSM in different coordinate systems were introduced and analyzed.Then,the traditional operation control mode of motor with speed sensor was introduced,and the simulation control model of permanent magnet synchronous motor was built based on SVPWM principle and id=0 current vector control principle,and the simulation verification of the control system was carried out.Secondly,aiming at speed sensorless control of PMSM,the basis of fuzzy PID,model reference adaptive and sliding mode control were mainly studied.First of all,the fuzzy control principle was studied,and the fuzzy PID was used as speed controller to realize the stable control operation of permanent magnet synchronous motor.Then the model reference adaptive principle and sliding mode controller principle were studied respectively and applied to sensorless control.Finally,the above three control methods were used for compound control research.In the research process,the above control methods were improved.In the model reference adaptive control strategy,Lyapunov function method was selected as the adaptive rule to adjust the reference model and control model,and the speed estimation expression was given.When sliding mode control was implemented,Tanh function was selected as the switching function to reduce chattering.In the design process of the whole system,a variety of measures to improve the stability were added,such as the motor side current measurement load appropriate frequency filter,motor rotor position compensation and the selection of appropriate fuzzy control law.This ensured the safety and stability of the control system and the motor.Finally,the simulation experiments were carried out to verify the model reference adaptive fuzzy control,sliding mode sensorless fuzzy control and model reference adaptive sliding mode control.Experimental results showed that the model reference adaptive sliding mode sensorless control strategy designed in this paper could quickly and stably control the start and stop of permanent magnet synchronous motor with short response time,and could quickly and stably adapt to a variety of different motor operating environment to ensure stable and accurate operation under complex conditions such as motor load change and motor speed change,with small speed error and good motor running stability.In addition,the model reference adaptive sliding mode control was tested experimentally in this paper.The test results showed that the system could accurately estimate the rotor speed of permanent magnet synchronous motor and maintain high system stability and accuracy under the operating condition of variable speed system.This method could be applied to the special motor running places.