Experimental Study On Speed Sensorless Vector Control Of Induction Motor Based On Fuzzy Extended Kalman Filter

In recent years,the speed sensorless vector control technology has attracted wide attention from scholars at home and abroad,and has become a research hotspot in the field of motor control.In this paper,the asynchronous motor speed estimation experiment based on fuzzy Extended Kalman Filter is deeply studied on the vector control experiment platform of three-phase asynchronous motor with DSP28335 as controller.Firstly,the experimental platform of vector control for three-phase asynchronous motor is designed,which is mainly divided into hardware circuit platform and software design.Aiming at the design of pre-charging circuit,this paper designs a pure hardware circuit method to realize the purpose of automatic cut-off of current-limiting resistance.A large number of experiments prove that the circuit can run stably for a long time,eliminating the potential safety hazards caused by the long-time access of current-limiting resistance to the circuit after the failure of system software.Secondly,for the problem of IGBT mis-conduction,the level conversion circuit and PWM wave logic judgment circuit are designed.The circuit can effectively monitor the PWM waveform in real time to prevent the IGBT from being mis-conducted.It is verified by experiments that the circuit can effectively protect the IGBT and improve the equipment security performance.For the problems of over-current,over-temperature,over-voltage and under-voltage of the inverter,on the basis of designing the safety of the hardware circuit protection equipment,the software can monitor the status of the inverter in real time,and improve the safety performance of the system through the combination of software and hardware.Furthermore,aiming at the problem that the fixed noise covariance matrix of the Extended Kalman Filter can not satisfy the dynamic and static requirements of the system at the same time,a fuzzy Extended Kalman Filter algorithm is proposed.A speed sensorless vector control model of induction motor based on fuzzy Extended Kalman Filter is established.A state discriminator and a fuzzy adaptive Extended Kalman Filter are designed.The simulation results show that the designed fuzzy Extended Kalman Filter is obviously superior to the traditional Extended Kalman Filter.Finally,in order to verify the performance of the proposed algorithm in the actual circuit,the comparative experiments of speed sensorless vector control based on Extended Kalman Filter and speed sensorless vector control based on fuzzy Extended Kalman Filter are completed on the experimental platform.The experimental results show that the fuzzy Extended Kalman Filter has better dynamic and static response and higher speed estimation accuracy in speed estimation.