On-site opening and closing consistency test method of high-voltage hybrid DC circuit breaker

Abstract

The invention discloses a high-voltage hybrid DC circuit breaker engineering on-site opening and closing consistency test method. When the hybrid DC circuit breaker is installed at the project site, the consistency test conditions may not necessarily be naturally met because the main wiring is fixed and cannot be adjusted. The closing consistency test method of the present invention includes the following steps: the modular multi-level converter connected to the DC circuit breaker is in an active charging state, the DC circuit breaker is in a closed state, and the remaining modular multi-level converters are in an active charging state. Isolate the uncharged and unlocked state; turn off the AC side switch of the modular multi-level converter connected to the DC circuit breaker, and disconnect the DC circuit breaker at the same time; after waiting time Tb, close the DC circuit breaker again and check the DC circuit breaker. Check whether the voltage characteristics of all IGBTs or modules on the circuit breaker transfer branch are consistent at the moment the circuit breaker is closed. The invention can timely understand whether the consistency of the DC circuit breaker meets the engineering operation requirements and reduce possible failure losses as early as possible.

Description

technical field [0001] The invention belongs to the field of testing of flexible DC power grids, in particular to a method for testing the consistency of opening and closing of high-voltage hybrid DC circuit breakers on site. Background technique [0002] The DC circuit breaker is one of the key technologies for the fault protection of the flexible DC grid. Since the DC current does not have a zero-crossing point, the research and development of the DC circuit breaker was once stagnant. With the proposal of the hybrid DC circuit breaker, the DC circuit breaker has once again entered people's field of vision, and it has also brought a boost to the development of the DC power grid. The hybrid DC circuit breaker is composed of main branch, transfer branch and energy consumption branch connected in parallel. Regardless of whether the hybrid DC circuit breaker is closing or opening, the consistency of each IGBT trigger on or off in the transfer branch is very important. If there...

AI Technical Summary

Problems solved by technology

When the hybrid DC circuit breaker is installed on the project site, the consistency test conditions may not be naturally available because the main wiring is fixed and cannot be adjusted.

However, as the operating life of the DC circuit breaker increases, the breakage of the equipment may cause the performance of the DC circuit breaker to change, and the consistency is no exception

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