Direct-current short-circuit fault ride-through control method and related device

Abstract

The invention discloses a direct-current short-circuit fault ride-through control method and a related device. The method comprises the following steps: breaking a direct-current circuit breaker on anisland side in a fault pole to remove a fault; determining a power transfer working condition type based on the rated capacity of the island side converter station in the non-fault pole and the active power transmitted during steady-state operation of the island side converter station; if the type of the power transfer working condition is a self-pinning working condition, controlling the islandside converter station in the non-fault pole to increase the output power so as to transfer all active power of the island side converter station in the fault pole through the island side converter station in the non-fault pole after the fault is removed; and if the type of the power transfer working condition is a non-self-pinning working condition, controlling the island side converter station in the non-fault pole to operate in a full-load state, and controlling the wind power plant to perform load increasing operation so as to transfer all active power of the island side converter stationin the non-fault pole through the island side converter station in the non-fault pole and the wind power plant after the fault is removed. The method can effectively reduce the fault influence range and maintain the power balance of the island system.

Description

technical field [0001] The present application relates to the technical field of flexible direct current transmission, and in particular to a method; it also relates to a device, a device, and a computer-readable storage medium. Background technique [0002] Due to the increase in power consumption of isolated island grids such as small islands on the sea and urban centers, it is difficult for the island's supporting power supply to meet the growing demand for electricity in the island. The flexible DC transmission system (ModularMultilevel Converter based High Voltage Direct Current, MMC-HVDC) based on the modular multilevel converter station adopts fully controlled power electronic devices, which can realize the autonomous shutdown of the devices, and have independent control of active and reactive power , dynamic compensation of AC reactive power shortage and supporting AC voltage, etc., and has the ability to supply power to passive islands. Therefore, MMC-HVDC island po...

AI Technical Summary

Problems solved by technology

In addition, the control strategy for the mutual conversion of MMC-HVDC between the networked and islanded operation states mainly includes the droop control strategy without switching. To withstand the short-circuit fault again in the island operation state; and the general control strategy of MMC-HVDC networking and island operation, by limiting the frequency command value and the inner loop current controller to achieve the purpose of improving the fault ride-through capability of the island system

[0004] However, the above-mentioned control strategies are all from the perspective of the converter station itself to improve the operation stability of the island system, without considering the coordination and cooperation among the various supporting equipment in the system, especially the research on DC short-circuit fault ride-through is blank

Images