Design And Research Of Permanent Magnet Linear Synchronous Motor Of Plunger Pump On Oil Well

Petroleum is one of the major energy sources nowsdays,so the research of oil production equipment is widely regarded.Traditional beam four connecting rod structure of production equipment has many problems such as the middle stage,the pipe deviation,the system flexibility and the low effciency.In order to improve these problems,the relevant researchers proposed a kind of pumping rodless production system directly driven by linear motor.This system does not exist well rod eccentric wear problem,and low efficiency.It has wide range to adjust capacity and easy adjustment.In this paper,a tubular permanent magnet linear synchronous motor is researched of its structure principle,electromagnetic calculation and optimization design.Based on the analysis and design of the motor,the following research work is carried out in this paper:Firstly,the structure and working principle of the motor are introduced.Based on the special structure and working principle of the motor,through the study of common rotary permanent magnet synchronous motor and linear induction motor electromagnetic parameters calculation method,the formulas for calculating the resistance and reactance parameters of the tubular permanent magnet linear motor,the loss of the primary core and the calculation method of the characteristic curve are given.The calculation of parameters,the.primary iron loss and the operating performance are calculated.The influence of the primary coil turns and the axial length of permanent magnet on the performance of the motor are discussed.Two dimensional finite element simulation models of motor are established by using Maxwell software.The no-load magnetic field distribution,no-load EMF,three-phase winding current and the motor overload capacity are analyzed,and the Fourier transform is used to obtain the fundamental and harmonic components.By comparing the performance of the motor under different structural parameters,the influence of the structural parameters to the performance of the motor is obtained.The cogging force of the motor is analyzed and weaken by changing the pole arc coefficient,slit width and the degree of uneven air gap.The influence of various factors on the cogging force are respectively analyzed.It provides evidence for reducing the cogging force and restraining the motor output thrust fluctuation.According to the requirements and the influence of the reference structure parameters to the motor performance,the final motor design scheme is determined.By using the finite element software,the simulation results show that the magnetic flux density distribution and the performance curve of the rated load are obtained.On the premise of meeting the requirements of motor design and manufacture of prototype,the prototype tests are carried out.The prototype tests results are compared with the finite element simulation results.The results show that the designed motor has good performance and meets the design requirements.The finite element models of tubular permanent magnet linear synchronousmotor respectively in silicon steel and soft magnetic composite material for primary core material are established,the no-load air gap magnetic field,the back EMF and the operation performance with rated load of two kinds of core material motor are analyzed.The comparison results show that the application of the soft magnetic composite material in the tubular permanent magnet linear synchronous motor is feasible.