Controllable weak magnetic technique combining magnetic structure with vector control of permanent magnet motor

Abstract

The invention provides a controllable weak magnet technology combining a permanent magnet motor magnetic circuit structure and vector control. The multipolar special rotor magnetic circuit structure of a rare-earth permanent magnet synchronous motor in a system can perform the magnetism regulating function, the controllable weak magnetism technology can be realized by the method that a controller uses a software control algorithm to conduct the vector control. The magnetic pole magnetic circuit of the rotor of the motor is designed into a permanent magnet embedded structure with salient pole effect and magnetic permeability of the magnetic circuit of an axis d more than the magnetic permeability of the magnetic circuit of an axis q; a current dividing magnetic circuit is arranged for facilitating the weak magnetic timing. A controller uses the software control algorithm to conduct space-voltage vector control, controls the direct axis current Id and the alternating axis current I q respectively, and implements large-scale weak-magnet speed expansion of the permanent magnet motor. The system has large practical value on the tractor vehicle driven by the electric force.

Description

Technical field [0001] The invention can be applied to traction vehicles driven by electric power, and adopts a rare-earth permanent magnet synchronous motor control system to drive the vehicle, so as to realize constant power and weak magnetic speed expansion in a wide range above the base speed. Background technique [0002] Due to the use of permanent magnet excitation, rare earth permanent magnet motors have significant advantages such as simple structure, reliable operation, small size, light weight, low loss, high efficiency, and flexible shape and size of the motor. However, permanent magnet motors use permanent magnets for excitation, which also makes it difficult to adjust the excitation, and it is difficult to achieve constant power and field-weakening speed expansion above the base speed. [0003] Different from the electric excitation synchronous motor, the rotor excitation of the rare earth permanent magnet synchronous motor is fixed, and the counter electromoti...

AI Technical Summary

Problems solved by technology

This is the defect of the traditional rare earth permanent magnet synchronous motor's weak field speed expansion, which seriously limits its further promotion and application

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