Temporary locking method, device and system for flexible direct current converter valve

Abstract

The invention discloses a temporary locking method, device and system for a flexible direct-current converter valve. The temporary locking method comprises the steps of obtaining a current value of each bridge arm of the flexible direct-current converter valve; when it is determined that a fault bridge arm with the current value larger than or equal to the temporary locking value exists, locking the fault bridge arm and a bridge arm in the same phase as the fault bridge arm, and sending a temporary locking signal to an upper-layer control system, so that the upper control system sends an unlocking command to the converter valve control system according to the temporary locking signal; and in response to the received unlocking command, judging whether the current value of the faulty bridge arm is smaller than the temporary locking value within a preset time, and if so, performing unlocking operation on the faulty bridge arm and the bridge arm with the same phase as the faulty bridge arm. By adopting the embodiment of the invention, the flexible direct-current converter valve can still have certain power transmission capacity when the alternating-current system fails, and the energy utilization rate of the flexible direct-current system is improved.

Description

technical field [0001] The invention relates to the technical field of power system faults, in particular to a method, device and system for temporarily locking a flexible DC converter valve. Background technique [0002] The fault response strategy of the flexible HVDC transmission system is an important part of the system design. In the current technology, when the AC system fault occurs in the flexible DC transmission system, the global temporary blocking strategy is usually adopted, that is, the transmission power of the flexible DC system is zero during the blocking period, and the power transmission is resumed after the fault is cleared, so as to realize AC fault ride-through , resulting in low energy utilization of the flexible DC system. Contents of the invention [0003] Embodiments of the present invention provide a method, device, and system for temporarily locking a flexible DC converter valve, which can ensure that the flexible DC converter valve still has a ...

AI Technical Summary

Problems solved by technology

In the current technology, when the AC system fault occurs in the flexible DC transmission system, the global temporary blocking strategy is usually adopted, that is, the transmission power of the flexible DC system is zero during the blocking period, and the power transmission is resumed after the fault is cleared, so as to realize AC fault ride-through , resulting in low energy utilization of the flexible DC system

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