Method and system for suppressing peak voltage at turn-off instant of fully-controlled power switching device

Abstract

The application discloses a method and a system for suppressing peak voltage at the moment of turning off of a fully-controlled power switching device, so as to suppress the high peak voltage generated at the moment of turning off of the fully-controlled power switching device. The method includes: acquiring the operation state information of the whole power electronic converter where a full-control power switch device is located; judging whether the full-control power switch device will generate more than The peak voltage of the preset voltage value; if so, reduce the turn-off speed of the full-control type power switch device until it is judged that the full-control type power switch device will not generate more than the preset value when it is turned off at the original turn-off speed. When the peak voltage of the set voltage value is reached, it will return to the original shut-off speed.

Description

technical field [0001] The present invention relates to the technical field of power electronics, and more particularly, to a method and system for suppressing peak voltage at the moment when a fully-controlled power switch device is turned off. Background technique [0002] The fully controlled power switching device represented by IGBT (Insulated Gate Bipolar Transistor, insulated gate bipolar transistor) is the core device of many power electronic converters. [0003] When the power electronic converter enters abnormal working conditions such as high voltage ride-through, low voltage ride-through or overload, the load current increases, resulting in an increase in the switching current change rate of the fully controlled power switching device. Due to the existence of parasitic inductance on the line, a larger switching current change rate will lead to a higher peak voltage generated by the fully-controlled power switching device at the moment of turn-off. In extreme case...

AI Technical Summary

Problems solved by technology

Due to the existence of parasitic inductance on the line, the greater the rate of change of the switching current will cause the higher peak voltage of the fully-controlled power switching device at the moment of turn-off, and in extreme cases, the peak voltage will exceed the full-controlled power switching device. withstand voltage value, causing overvoltage breakdown of fully controlled power switching devices

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