Switched reluctance motor rotor position square wave signal fault diagnosis and fault tolerance method

Abstract

The invention discloses a switched reluctance motor (SRM) rotor position square wave signal fault diagnosis and fault tolerance method, comprising the steps of: performing Fourier expansion spectrum analysis on the position square wave signal outputted by an SRM position sensor; diagnosing in real time whether the position square wave signal goes wrong by checking whether a secondary harmonic coefficient is zero; determining that the position sensor is out of order if the secondary harmonic coefficient is not zero, thereby realizing real time fault monitoring and diagnosis; and based on a position signal fault tolerance control method after a position square wave signal fault, utilizing residual normal position square wave signals to calculate a rotor rotating speed and to estimate an average rotating speed after the diagnosis that the position square wave signal outputted by the position sensor goes wrong, and utilizing the average rotating speed to calculate a rotor position to realize fault tolerance control after position square wave signal faults, thereby improving the reliability of an SRM driving system, and avoiding SRM control failure caused by rotor position signal decoding disorder.

Description

technical field [0001] The invention relates to a fault diagnosis and fault tolerance method, in particular to a fault diagnosis and fault tolerance method for a square wave signal of a rotor position of a switched reluctance motor, belonging to the technical field of motor signal detection. Background technique [0002] The switched reluctance motor itself has important characteristics such as simple and sturdy structure, suitable for high-speed, high-temperature operation, and strong fault tolerance. Position detection is one of the most critical links in the switched reluctance motor system, and it is also a weak link. The accuracy and reliability of the position signal directly affect the control performance of the switched reluctance motor system, and are important indicators related to the strong fault tolerance of the switched reluctance motor itself. [0003] Traditional position detectors are mainly photoelectric encoders, magnetic sensors, eddy current sensors and...

AI Technical Summary

Problems solved by technology

For switched reluctance motors, the conventional detection method is to use photoelectric and Hall sensors for position detection, and the output position search pulse is usually a multi-channel square wave signal. Whether the square wave signal is correct or not is directly related to the switch magnetism. Estimation of motor drive signal, serious position signal error will lead to motor stall and damage to power converter

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