One-phase open-circuit fault-tolerant control method for six-phase permanent magnet synchronous motor

Abstract

The invention provides a one-phase open-circuit fault-tolerant control method for a six-phase permanent magnet synchronous motor, and relates to the technical field of multi-phase motor control. The method comprises: aiming at fault tolerance research after one-phase open circuit of the six-phase permanent magnet synchronous motor with the phase displacement of 30 degrees, using a neutral point isolation mode, considering the influence of fifth harmonic waves, providing a six-phase static coordinate transformation matrix corrected after a fault is established, and establishing a voltage and torque mathematical model under fundamental waves according to the matrix and a rotating coordinate transformation matrix; under the condition that a no-load air-gap magnetic field is not sinusoidal, deriving a mathematical model of a quintuple harmonic space, analyzing the coupling relation of d-q subspaces in a voltage equation transformed by a rotation transformation array, and providing a secondary rotation coordinate transformation array and a voltage compensation formula for eliminating d-q axis voltage coupling after decoupling. In consideration of the influence of the quintuple harmonicflux linkage and inductance on the voltage and torque of the six-phase permanent magnet synchronous motor in a fault-tolerant mode, torque pulsation containing four times of angular frequency and sixtimes of angular frequency is eliminated by injecting quintuple harmonic.

Description

technical field [0001] The invention relates to the technical field of multi-phase motor control, in particular to a one-phase open-circuit fault-tolerant control method of a six-phase permanent magnet synchronous motor. Background technique [0002] With the development of power electronics technology, the motor system is not limited to the three-phase power supply mode. The multi-phase motor drive system has attracted extensive attention under the conditions of low voltage, high power, high reliability and safety, especially in aerospace, ship propulsion, new energy vehicles, etc. In the application, if a device failure is found, it must be found and solved in time, and the system is even required to be able to operate with fault tolerance. [0003] When a phase loss fault occurs in a traditional three-phase motor, the neutral point of the motor must be connected to the midpoint of the DC bus, otherwise it will be reduced to a single-phase motor and cannot be self-started....

AI Technical Summary

Problems solved by technology

[0004] Aiming at the deficiencies of the prior art, the present invention provides a six-phase permanent magnet synchronous motor one-phase open-circuit fault-tolerant control method, which solves the problem of reducing the torque ripple after the fault-tolerant control of the six-phase permanent magnet synchronous motor, and at the same time considers the 5th harmonic inductance , Flux linkage, minimize 4,6 times angular frequency torque ripple

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