DC current limiter and its driving method

Abstract

The invention provides a DC current limiter topology, a drive method therefor and a DC current limiter, and relates to the technical field of power transmission and distribution. A DC fault current can be limited, and the probability of phase change failure of a system is reduced. The DC current limiter topology comprises four bridge arms: a first upper bridge arm, a first lower bridge arm, a second upper bridge arm, and a second lower bridge arm. The four bridge arms are respectively formed by the series connection of a plurality of thyristors. The first upper and lower bridge arms are connected in series, and the second upper and lower bridge arms are connected in series. Moreover, a branch circuit formed by the series connection of the first upper and lower bridge arms is in parallel connection with a branch circuit formed by the series connection of the second upper and lower bridge arms. The DC current limiter topology also comprises a reactor and a capacitor, which are connected in series. One end of a branch circuit formed by the series connection of the reactor and the capacitor is connected between the first upper and lower bridge arms, and the other end of the branch circuit is connected between the second upper and lower bridge arms. According to the invention, the technical scheme is applied in a DC system, and a direct current is limited when the system has a fault.

Description

technical field [0001] The invention relates to the technical field of power transmission and distribution, in particular to a DC current limiter and a driving method thereof. Background technique [0002] With the continuous improvement of my country's transmission capacity and the development of power electronics technology, HVDC transmission has been widely used in long-distance and large-capacity transmission due to its unique technical and economic advantages. The traditional point-to-point DC transmission system can be expanded into a DC grid, of which the flexible DC transmission grid is the main development direction, which has many characteristics of stable and reliable grids, and also provides convenience for large-scale access of distributed energy. [0003] Most of the current DC transmission systems are point-to-point transmission, and there are very few multi-terminal transmissions. The main reason for this problem is that there is no effective measure to limit...

AI Technical Summary

Problems solved by technology

[0003] Most of the current DC transmission systems are point-to-point transmission, and there are very few multi-terminal transmissions. The main reason for this problem is that there is no effective measure to limit the fault DC current when the DC transmission system fails, and the DC current rises rapidly during the fault period. commutation failure

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