The method of increasing the value of the arc extinguishing angle according to the area value setting when the DC commutation fails

Abstract

The invention discloses a method for setting and increasing the value of the arc extinguishing angle according to the value of the area value for DC transmission commutation failure. In the DC power transmission system, the value of the commutation area of ​​the AC grid voltage is calculated. When a commutation failure occurs, the value of the commutation area is used , to set the value of arc extinguishing angle required to increase the arc extinguishing angle control operation. The voltage commutation area of ​​the AC grid is: the area of ​​the arc overlapping area, the area of ​​the arc extinguishing area, or the area of ​​the arc overlapping area+the area of ​​the arc extinguishing area. There are linear method, limiting linear method, step method, step plus linear method to increase arc extinguishing angle value according to area value setting. According to the different degrees of faults in the AC power grid, different angle values ​​for increasing the arc extinguishing angle are selected; thus, the control operation of increasing the arc extinguishing angle can not only more effectively avoid the continuous commutation failure under the serious fault degree, but also avoid the damage caused by the minor fault degree. DC transmission brings large disturbances.

Description

technical field [0001] The invention relates to a method for setting and increasing the numerical value of the arc-extinguishing angle according to the numerical value of the area in case of DC transmission commutation failure. In particular, it involves high-voltage / ultra-high voltage direct current transmission based on thyristor single-control devices, excluding high-voltage direct current transmission based on full-control devices such as IGBT / IGCT. Background technique [0002] At present, there are many high-voltage direct current transmission projects in operation in China, and most of them are high-voltage direct current transmission projects based on thyristor single-control devices. System structure such as figure 1 shown. It usually consists of a converter station and a DC line; the converter station is usually divided into a rectifier station and an inverter station; each converter station is composed of an AC grid, a converter transformer, a converter, etc.; a...

AI Technical Summary

Problems solved by technology

At the same time, if a larger and increased arc-extinguishing angle is fixedly selected, when a slight AC grid fault causes commutation failure, due to the control operation of increasing the arc-extinguishing angle and selecting a larger angle, there will be a greater impact on DC transmission disturbance

Images