Model prediction-based three-phase inverter fault online diagnosis method

Abstract

The present invention relates to a model prediction-based three-phase inverter fault online diagnosis method. According to the method, an inverter system reference model of closed-loop control is built; the prediction values of the model are compared with actual observation values, so that the residuals of state variables are obtained; the relationships of the residuals and threshold values are analyzed; whether an open-circuit fault has occurred is judged, an alarm is given, and a fault diagnosis instrument is started; the fault diagnosis instrument is an on-line diagnosis mechanism which is built according to preset fault conditions; and the fault diagnosis instrument evaluates the values of state variables which are abnormal currently, selects a fault state which is closest to an actual state and accurately positions a fault switching device. The model prediction-based three-phase inverter fault diagnosis method of the invention has the advantages of few input quantities, high real-time performance, no need for additional detection circuits and capability of accurately positioning the fault switch device, is especially suitable for the fault diagnosis of closed-loop control-based complex power electronic circuits.

Description

Technical field [0001] The invention relates to a three-phase inverter fault online diagnosis method based on model prediction. Background technique [0002] The rapid development of power electronic technology has made power electronic devices widely used in many fields such as power systems, transportation, aerospace, communications engineering, and iron and steel metallurgy. With the increasing complexity of technology and higher and higher requirements for system safety and reliability, electronic electronic devices are often used as key equipment in the production process. The loss caused by the failure of power electronic devices is huge. On the other hand, the reliability of power electronic circuits is a relatively weak link for the entire system. As the main body of energy conversion, it has the highest failure rate and the most serious consequences caused by failure. Redundant design and fault-tolerant control based on fault diagnosis can greatly improve the reliabili...

AI Technical Summary

Problems solved by technology

[0004] In view of this, the object of the present invention is to provide a three-phase inverter fault online diagnosis method based on model prediction, which solves the problem of slow detection speed in the existing fault diagnosis method, the need for additional detection circuits, and the difficulty in accurately locating faults Disadvantages of switching tubes, etc.

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