Study On Tubular Flux-switching Permanent Magnet Linear Motor For Direct-Drive Pumping Unit

As the main source of energy in industrial production,oil is the lifeblood of the national economic development strategy,the development of drilling technology and the improvement of oil production has become the main way to solve the world energy crisis.So far,however,pumping unit of large-scale use in oil field production,are widespread with problem,such as low system efficiency,poor system stability and poor security.To solve the above problems,linear pumping unit arises at the historic moment,the pumping unit is directly driven by linear motor,the system does not need deceleration and intermediate conversion device,is the fundamental change of traditional pumping unit system.This paper discusses a new kind of pumping unit system directly driven by linear motor,different from the traditional linear electromagnetic pumping machine,the new pumping unit system with the method of direct balance,canceling the counterweight,which can effectively improve efficiency of the system and achieve the purpose of saving energy.Linear motor as the core part of the new type pumping unit system is the main object of this article.This paper firstly summarizes the domestic and overseas characteristics and research status of pumping unit,discusses a new pumping unit system directly driven by permanent magnet flux switching linear motor,and introduces the general structure and working principle of the system.Secondly,analyzes the structure characteristics and working principle of permanent magnet flux switching linear motor,the basic equation and mathematical model of dq0 coordinates are derived.Then,according to the design characteristics of rotating permanent magnet flux switching motor,the cylindrical permanent magnet linear flux switching motor is designed and a two-dimensional physical model is established,the basic characteristics and the influence of structure parameters on the motor are analyzed based on finite element method.Finally,based on the analysis of the existing detent force optimization method of permanent magnet linear motor,the method of adding auxiliary tooth in the end is adopted to optimize the detent force of the motor.