Key Structure Design Of Permanent Magnet Synchronous Motor For Direct-drive Submersible Screw Pump

Screw pump production system has advantages of high efficiency, smooth operation, long pump inspection cycle for exploitation of heavy oil, high sand and waxy crude oil, crude oil with high gas. In submersible screw pump unit, the reducer unit leads the whole transmission system long, construe complicated, low efficiency, complex for operation, manufacture and maintenance. So, we put forward the development of direct-drive submersible screw pump system. The permanent magnet synchronous motor(PMSM) output low speed and high torque to drive the screw pump production system directly, without using the reducer. Permanent magnet synchronous motor is the most important part of this system and there is the key structure design of permanent magnet synchronous motor for direct-drive submersible screw pump.This paper expounds on the PMSM structure design process. Based on the PMSM requirements and electromagnetic design, we give two design scheme, optimize the second scheme design, choose high magnetic permanent magnets and give the calculation method of permanent magnet size; We also use new bearing and adopt the method of segmental fixation; for the convenience of fixing thread, use the single layer winding; and design a new type of cable joint to enhance the sealing effect, reduce the operation time, operation material, improve the working efficiency.Using Solidworks and ANSYS Workbench software to simulate motor spindle, verify motor spindle mechanical properties. The unilateral magnetic force is calculated and the deflection caused by unilateral magnetic force is further analyzed; the Structure intensity of bearing, splin and other key components is calculated. The wastage of motor are given in this paper. The friction loss of motor rotor are simulated by using ANSYS, and compared with the calculated results. Accurate calculation of the loss lay the foundation for follow-up study.