Study On The Control Of Permanent Magnet Synchronous Submersible Motor In Waterworks Based On Fuzzy Prediction

Permanent magnet synchronous motor and supporting pump components constitute a submersible pump system,with high efficiency,energy saving,small size,light weight,simple and flexible structure,strong reliability and other advantages,can be submerged in underground water,rivers,lakes and other natural waters to work.In the practical application of the water plant,the working condition characteristics have strict requirements on the control strategy of the motor,such as precisely controlling the change of speed and load torque in the variable frequency speed regulation of the motor,and keeping the outlet pressure stable through the change of the motor speed.No matter the traditional double closed-loop vector control or the improved model predictive control based on vector control,there are defects such as insufficient dynamic performance,long starting time and large overshoot,which have a negative impact on the life of the motor.Aiming at the shortcomings of vector control and predictive control,putting forward a control strategy based on fuzzy prediction technology combined with the application condition of submersible motor in waterworks in this paper.In speed predictive control system,the parameter used for suppress error remains constant,which would lead a result that motor cannot meets the requirements of both good dynamic response and stable control,therefore setting up the fuzzy controller based on speed loop predictive control system.Through the fuzzy reasoning of the speed error,the real-time correction of the predictive control error is achieved,so that the dynamic performance of motor was improved effectively,at the same time the loss and oscillation of motor was reduced,which achieves the purpose of energy saving.Based on mathematical model of permanent magnet synchronous motor and the structure of fuzzy prediction algorithm,the simulation model was built in Matlab/Simulink.Three working conditions: submersible motor load starting,double torque starting and constant pressure water supply were simulated with the actual engineering data.Finally,the simulation results were compared with vector control and predictive control algorithms.The simulation results verify the optimization effect of fuzzy predictive control on the dynamic and static performance of submersible PMSM.The recovery time of water pressure was shortened and the robustness was improved in the constant pressure water supply.