Modular multi-level converter valve sub-module igbt fault detection system and method

Abstract

The invention discloses a fault detection system and method for a modular multi-level converter valve submodule IGBT (Insulated Gate Bipolar Translator). The system mainly comprises a self-energy extraction system, a pulse generation system, a trigger control system, a fault detection system and a data processing system. The method comprises the following steps that: 1) the pulse generation systemgenerates pulses, and transmits the pulses to the modular multi-level converter valve submodule IGBT; 2) the fault detection system acquires a response signal U<k> coupled by a gate pole of the modular multi-level converter valve submodule IGBT under pulsed excitation; and 3) the data processing system processes the response signal U<k>, and makes judgment to obtain a fault type. Energy is extracted from an energy storage capacitor of a submodule through the self-energy extraction system, thereby solving the problem of lack of an external power supply.

Description

technical field [0001] The invention relates to the technical field of electric equipment fault detection, in particular to a modular multilevel converter valve sub-module IGBT fault detection system and method. Background technique [0002] In recent years, the flexible DC transmission system has developed rapidly. The flexible DC converter valve adopts the structural form of modular multi-level sub-modules connected in series. The reliability of the sub-modules is very important to the system. Seriously, it will lead to a chain reaction; if the sub-module has an open-circuit fault, the sub-module cannot operate in the normal working mode, which will cause a large circulating current in the bridge arm. Therefore, modular multi-level fault monitoring is of great significance to adjust the control mode to reduce faults, improve reliability and power outage maintenance. [0003] The IGBT, the core component of the sub-module, is the most vulnerable part. According to the loca...

AI Technical Summary

Problems solved by technology

The traditional method is to modify the IGBT to embed the sensor, or use an infrared camera to measure the case temperature to roughly estimate the chip junction temperature. These methods have the advantage of being easy to go online, but there are problems of high cost of modifying the IGBT and low measurement accuracy; the new The thermally sensitive electrical parameter junction temperature extraction method overcomes the need to modify the IGBT and the problem of measurement accuracy, but this method often requires an external power supply, and has high requirements for the power supply, and is highly intrusive to the system; at the same time, the thermally sensitive electrical parameter junction temperature extraction The method requires high measurement accuracy, and the data flow pressure of the many sub-modules of the converter valve is huge

[0006] The current sub-module fault detection method has problems such as complex algorithm, large amount of measurement, and high system intrusion

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