Study On The Optimization Design Of Submersible Permanent Magnet Linear Synchronous Motor

With the decrease of oil reservoir and the increase of water content,more and more requirements of the reciprocating electric submersible pump lifting technologies are elicited on the efficiency,lifting force,safety and energy saving performance.However,permanent magnet linear synchronous motor as a power machine has a significant impact on the overall system performance.In order to obtain the best driving performance of the reciprocating submersible piston pump system,this paper takes the cylinder submersible permanent magnet linear synchronous motor(CSPMLSM)as the research object,combined with the school enterprise cooperation project(the development of piston pump production system with submersible permanent magnet linear synchronous motor),carried out the magnetic poles topological analysis,electromagnetic structure parameters optimization design,experimental test analysis and several other aspects of research,mainly included the following details.(1)Based on the structure and working principle of CSPMLSM,the topology analysis of the magnets of the rotor is carried out and four new Quasi-Halbach permanent magnet arrays are proposed.The performances of the closed slot and semi-closed slot motors under different magnetic pole structures are compared and analyzed.The steady-state magnetic field distribution,no-load air-gap flux density,no-load back-EMF,stator teeth magnetic density,permanent magnets eddy current loss,cogging force fluctuations and other performance indicators are analyzed?The dual-layer composite modular magnetic pole structure is finally determined as mover structure of CSPMLSM.(2)For the 114 series CSPMLSM,the design of the submersible linear motor was studied.The overall mechanism of the motor and the slot coordination scheme are established,and the main dimensions of the motor,stator slots,armature windings and permanent magnets are designed.The analytical model of the modular Quasi-Halbach array is established in the polar coordinate system,and the partial differential equation of scalar magnetic bit is solved by the separation variable method,and the general expression of the solution domain is obtained.After completing the preliminary design of permanent magnet synchronous motor,the transient magnetic field simulation of the designed motor is analyzed by using Ansoft software.The correlation analysis of the transient characteristics of the motor provides a basis for further optimization of the motor.(3)Taking the motor thrust fluctuation and cogging force as the optimization goals,the electromagnetic parameter optimization design was carried out.The main 7 electromagnetic structural parameters for significant factor are screened by fractional factorial design of DFSS.Aiming at the problem of the real function relationship between motor performance indicators and salient factors,response surface methodology(RSM)was used to fit the corresponding second-order response model and determine the validity of the model.The Pareto optimal solution was obtained by multi-objective genetic algorithm and the optimal structural parameter combination was obtained.The simulation results before and after the optimization show that the optimization method based on Fractional Factorial Design and RSM that is applied to optimize the electromagnetic structure parameters of linear motor is feasible.According to the optimization results,the motor structural parameters are corrected,finally.