Structural Design And Performance Optimization Of High Efficiency Flux Switching Motor For Pumping Unit

With the deepening of China’s oil exploitation,the exploitation of high viscosity oil wells and deep oil wells is becoming more and more common,which leads to a significant increase in the difficulty and cost of mechanical oil extraction.The problems of low efficiency and high energy consumption of traditional pumping units also follow.Combined with China’s new measures to promote energy conservation and consumption reduction at this stage,the research of new pumping units is very important to reduce the cost of oilfield development and encourage the development of energy industry.Different from the traditional rotor permanent magnet motor,flux switching permanent magnet machines(FSPM)overcomes the weakness of stator permanent magnet motor and becomes the most promising double salient permanent magnet motor.Firstly,this paper expounds the background and research status of flux switching motor.By describing the traditional FSPM in detail and comparing the working principle of the traditional FSPM,it is demonstrated that the V-type FSPM has similar magnetic flux switching principle,winding consistency and complementarity,explains the reason why the output waveform of back EMF is sine wave,and provides a mathematical model for further demonstration of vector control strategy.Secondly,according to the relationship between the parameters of V-type FSPM and traditional FSPM in this design scheme,the initial parameter size of the motor is obtained,and the overall design process is given.The two motors are compared and analyzed,including magnetic field distribution,permanent magnet flux,no-load back EMF,inductance,torque and iron loss.The research shows that it corresponds to the previous theory.Finally,in order to improve the efficiency and output torque of the motor and reduce the cogging torque,based on the multi-objective optimization algorithm and finite element method,this paper studies the influence of the change of the main size parameters of a 6 / 8-pole V-type FSPM on the overall performance of the motor,and finally obtains the reference values of the main structural parameters most suitable for the motor.These reference values will lay a foundation for the design,optimization and control of other V-type FSPMs.The vector control simulation of V-type FSPM is established based on MATLAB /Simulink.The results show that the mathematical model is correct and has good steady-state performance.