Diagnosis method, device and electronic equipment for open-circuit fault of three-level inverter

Abstract

The invention discloses a method for diagnosing an open-circuit fault of a three-level inverter, comprising: obtaining the line voltage data between A and B phases and the line voltage between B and C phases in the inverter through a voltage transformer data; use the line voltage data between the A and B phases as the abscissa, and use the line voltage data between the B and C phases as the ordinate to draw a voltage locus diagram in a cycle; for the existing fault voltage The trace set is retrieved, and if a set item in the existing fault voltage trace set matching the voltage trace diagram is retrieved, the fault type corresponding to the retrieved set item is output as a diagnosis result. This method realizes the non-intrusive diagnosis of the open-circuit fault of the three-level inverter. It can diagnose the single-tube fault and the two-tube fault, and can also distinguish the open-circuit fault of the diode, and it is not affected by the load. It is still available in case of failure, and has the effects of being simple, convenient, fast, accurate, and less affected.

Description

technical field [0001] The invention relates to the field of power electronics, in particular to an open-circuit fault diagnosis method, device and electronic equipment for a three-level inverter. Background technique [0002] Three-level inverters are also called three-phase inverters (usually called A, B, and C three-phase, and the phase voltage is U A , U B , U C , the cable voltage U between the two phases AB , U BC , U AC ), are widely used in industrial production, but due to the sensitivity of its own components and the uncertainty of the working environment, its failure rate has always been high in power electronic systems. Generally, semiconductor power tube faults in three-level inverters are generally divided into two types: short-circuit faults and open-circuit faults. The open-circuit fault diagnosis technologies for semiconductor power tubes emerge in endlessly, which can be mainly divided into two types: voltage diagnosis method and current diagnosis meth...

AI Technical Summary

Problems solved by technology

Although the existing open-circuit fault diagnosis technologies have their own advantages, there are many objective conditions that are difficult to change in the three-level inverter in some applications, which restrict the application of many methods.

For example, the system on the locomotive is not allowed to be modified at will, and it is difficult to diagnose the open circuit fault of the system by obtaining its control signal or installing an additional voltage sensor

At present, there is no non-invasive method for single-tube open-circuit and multi-tube open-circuit fault diagnosis of semiconductor power tubes using external voltage.

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