Novel combined type DC breaker and application method thereof

Abstract

The invention provides a novel combined type DC breaker, comprising a transferring branch, an energy absorption branch, and at least two main branches and at least two auxiliary branches. The transferring branch is in parallel with the energy absorption branch. The main branch is corresponding to the auxiliary branch in a one-to-one manner. The main branch is connected to the DC outlet of a DC busin a high-voltage direct current (HVDC) transmission system. The auxiliary branch is in series with the transferring branch, and then is in parallel with the two ends of the main branch correspondingto the auxiliary branch. Compared with the prior art, the invention is advantageous in that the application economy performance of a high-voltage DC breaker in a flexible DC grid can be improved; theestablishment of the DC grid and the popularization and application of the mixed type DC breaker can be facilitated.

Description

technical field [0001] The invention relates to the technical field of power electronics, in particular to a novel combined DC circuit breaker and an application method thereof. Background technique [0002] Flexible DC transmission technology provides an effective solution for the grid connection and consumption of large-scale renewable energy, and it has a wide range of application requirements and markets around the world. However, due to the lack of DC circuit breakers suitable for high-voltage DC systems, the development and construction of flexible DC grids are greatly restricted. [0003] At present, high-voltage DC circuit breakers mainly include hybrid DC circuit breakers, which take into account the advantages of low operating loss of mechanical DC circuit breakers and fast breaking of solid-state DC circuit breakers. For example, the hybrid DC circuit breaker prototype developed by ABB has good high-voltage technical performance, its rated voltage reaches 200kV, ...

AI Technical Summary

Problems solved by technology

However, this hybrid DC circuit breaker contains a large number of high-power fully-controlled power electronic devices. Due to factors such as low withstand voltage and high price of a single tube of high-power fully-controlled power electronic devices, the cost of hybrid DC circuit breakers is high.

[0004] Both sides of each DC transmission line of the flexible DC grid need to be equipped with high-voltage DC circuit breakers to achieve rapid isolation of faulty lines. Therefore, as the transmission scale of the flexible DC grid continues to increase, the number of applications of high-voltage DC circuit breakers has also increased exponentially. Further increase the investment cost of the flexible DC grid, which is not conducive to its development and construction

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