Three-phase inverter short-circuit fault detection method

Abstract

The present invention discloses a three-phase inverter short-circuit fault detection method. The method comprises: collecting a line voltage in a three-phase inverter and converting the line voltage into a phase voltage; performing DQ decoupling processing on the line voltage and the phase voltage to obtain active component detection values, reactive component detection values, and zero sequence component detection values respectively corresponding to the line voltage and the phase voltage; setting active component standard values, reactive component standard values, and zero sequence component standard values respectively corresponding to the line voltage and the phase voltage during the normal operation of the three-phase inverter according to the specific inverter; comparing the detection values corresponding to the line voltage with the corresponding standard values, and the detection values corresponding to the phase voltage with the corresponding standard values, and determining whether there is a fault to the three-phase inverter according to the comparison results; if there is no fault, allowing the three-phase inverter to continue to operate; if there is a fault, determining a fault occurrence position according to the phase voltage and the line voltage and the corresponding detection values; and according to the fault occurrence position, executing pulse blocking protection on the switch or disconnecting a main contactor to stop the inverter operation, and ending the test.

Description

technical field [0001] The invention relates to a fault detection method in a power system, in particular to a detection method for a short-circuit fault of a three-phase inverter. Background technique [0002] With the rapid development of my country's railway industry, the electrical equipment on the train tends to be diversified and complicated, making the normal operation of the railway transportation system inseparable from the auxiliary converter, and put forward the quality and reliability of the power supply of the auxiliary power supply system. higher requirement. When there is a phase-to-phase short circuit or a ground short circuit in the auxiliary inverter of the train, the pressure of the short-term passing current of the switch tube increases, which is likely to cause the switch tube to burn out. Moreover, the output current of the inverter increases sharply, causing all electrical appliances connected to the auxiliary converter to be damaged at the moment of f...

AI Technical Summary

Problems solved by technology

When the auxiliary inverter of the train has a phase-to-phase short circuit or a ground short circuit, the pressure of the current passing through the switch tube will increase for a short time, which may cause the switch tube to burn out

Moreover, the output current of the inverter increases sharply, causing all the electrical appliances connected to the auxiliary converter to be damaged at the moment of failure.

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