Device for monitoring state and diagnosing fault of power electronic circuit

Abstract

The invention discloses a device for monitoring the state and diagnosing the fault of a power electronic circuit. The device has a structure that: a magnetic field detection module detects the magnetic field strength of the power electronic circuit, a signal conditioning module amplifies a voltage signal and an analog-to-digital conversion module performs analog-to-digital conversion; a fault diagnosis module comprises a time-domain and frequency-domain conversion module, a characteristic sort module and a comprehensive diagnosis module; the time-domain and frequency-domain conversion module is used for extracting the frequency characteristics of a time-domain waveform and supplies the frequency characteristics to characteristic sort sub-modules respectively; the characteristic sort sub-modules compare the received subsets to obtain partial diagnosis results corresponding to each characteristic subset and supply the results to the comprehensive diagnosis module; and the comprehensive diagnosis module synthesizes the partial diagnosis results of each characteristic subset to obtain a final diagnosis result. The device realizes the natural isolation of a detector from a main circuit; the different kinds of information carried by the magnetic field signal are treated respectively and then comprehensively judged, so the accuracy is higher; and the device can be applied to various power electronic circuits.

Description

technical field [0001] The invention relates to a power electronic circuit technology, in particular to a state monitoring and fault diagnosis device for a power electronic circuit, which is a non-contact state monitoring and fault diagnosis device for a power electronic circuit based on magnetic field near-field radiation. Background technique [0002] With the rapid development of power electronic technology, power electronic products represented by switching power supply, UPS power supply and variable frequency power supply have been widely used in all walks of life, and their normal operation is crucial to ensuring the safety of power systems and industrial production processes , high-efficiency, and high-quality operation are very important, so its reliability, fault diagnosis and function reconstruction technology, and electromagnetic compatibility are all topics that must be studied. Fault diagnosis of power electronic circuits can detect abnormalities in the circuit ...

AI Technical Summary

Problems solved by technology

[0005] ① Due to the need for measuring components such as voltage and current transformers and Hall, and the detection components have parasitic parameters, the detection circuit cannot actually be completely isolated from the main circuit, the electromagnetic interference is large, and the diagnosis may be biased;

[0006] ②For medium and high voltage large-capacity converters, the voltage is high and the current is large, which requires large voltage and current transformers, and the cost is high;

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