Electromagnetic Optimization Of Submersible Permanent Magnet Linear Synchronous Motor

Submersible permanent magnetic linear synchronous motor(SPMLSM)drives plunger pump directly for pumping oil,and it eliminates the need of reducer in the rotary motor pumping oil system.In addition to the elevated efficiency of the system,it saves the lifting power that the oil sucker rod required and gets rid of the problem about well tube eccentric wear thoroughly.It used in low yielding wells,inclined shaft,cluster wells,horizontal wells and viscous crude oil wells,and so on.Therefore,to study the new technique has become a entirely new direction for pumping oil.Cylinder permanent magnet linear synchronous motor(CPMLSM)is the engine to power the pumping oil system,and is the key to the normal operation of the system.Its performance affects the quality and service life of the system directly,and also has influence on the oil production and the production cost.Hence,improving the performance of CPMLSM and the efficiency of the operation,which aim to achieve the purpose of energy saving and efficiency improving.In this paper,the purpose is to improve the thrust of SPMLSM,reduce its cogging force,and to study the optimization design of motor electromagnetic parameters.Firstly,designed the electromagnetic scheme of SPMLSM.According to the working conditions of SPMLSM,determined the motor's rating data and structure.And for CPMLSM three directions of magnetization,namely magnetized in the axial direction and radial direction,mixed direction,compared the motor performances of air gap flux density,no-load back EMF,cogging force and teeth of the stator magnetic density,and ultimately determined suitable magnetizing method of SPMLSM.Secondly,carried out the optimization design of electromagnetic parameters of SPMLSM by experiment design method.The thrust of the motor and the cogging force are the optimization objectives,the 7 structural parameters of motor which affect the motor performance are the optimization variables.Used the partial factorial experiment to find out the significant factors that affected the thrust and cogging force of the motor;By response surface method,fitted the two order response models of the thrust force and the cogging force of the motor by the significant factor,and judged the significance of the model;Through the multi objective optimization,found the optimal solution to make the motor with the maximum thrust and the minimum cogging force;Considered the influence of the error of the motor in the actual manufacturing and installation process,carried out the robust parameter design of SPMLSM based on Taguchi method.According to the above optimization results,designed the structure of SPMLSM.Finally,based on the Windows operating system environment,designed the computer aided software for SPMLSM.Programmed the linear motor design interface by using Visual Basic,to realize the function of the linear motor design data input,storage,design,performance calculation,display list of design,display curves,Which provide help for the linear motor electromagnetic parameters design and verify the accuracy of the electromagnetic calculation formulas.