Dual-long-secondary and primary permanent magnetic field modulation linear motor for oil pumping unit

Abstract

The invention discloses a dual-long-secondary and primary permanent magnetic field modulation linear motor for an oil pumping unit. The motor comprises two long secondary stators arranged symmetrically and oppositely, a short primary rotor arranged between the two long secondary stators, and air gaps formed between the short primary rotor and the long secondary stators, wherein the short primary rotor comprises primary iron cores arranged at equal intervals in a motion direction, and primary permanent magnets embedded between the adjacent primary iron cores; the primary iron cores are wider than the primary permanent magnets, so that primary teeth are formed on two sides of each primary iron core in the width direction; and armature windings are nested on the primary teeth. According to the motor, the armature windings and the permanent magnets are all arranged in the short primary rotor; the long secondary stators only adopt salient pole flat plate structures composed of magnetic materials; a primary magnetic field is modulated by air gap permeance changes caused by secondary salient poles to realize electromechanical energy conversion; and the motor has the characteristics of simple structure, high reliability, low cost and high thrust density.

Description

technical field [0001] The invention relates to a double-sided long secondary primary permanent magnet field modulation linear motor for an oil pumping unit, and belongs to the technical field of linear motors for oil pumping. Background technique [0002] The beam pumping unit utilizes electric energy to convert it into rotary motion, and then converts it into linear reciprocating motion through a four-bar linkage after deceleration. The energy loss of its transmission system is as high as 28%. In addition, the rotation characteristic causes a large starting torque, and the system efficiency is generally not good. More than 30%. The linear motor pumping unit directly converts electrical energy into linear reciprocating motion, which simplifies the mechanical transmission process and effectively improves the efficiency. Moreover, when the stroke is increased, the overall size and weight of the whole machine will increase very little, especially the pumping parameters can be ...

AI Technical Summary

Problems solved by technology

In order to solve the problems of large amount of permanent magnets and high processing costs in the secondary long stator structure of the permanent magnet synchronous linear motor used in the existing linear motor pumping unit for oil extraction, the present invention also draws on the high Power density characteristics, providing a bilateral long secondary primary permanent magnet type field modulated linear motor topology with both armature windings and permanent magnets placed on the primary

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