Fault control method, system, device and medium for flexible direct current power transmission system

Abstract

The application discloses a fault control method, system, equipment and medium of a flexible direct current power transmission system, and the method is as follows: acquiring real-time electrical quantities of the flexible direct current power transmission system, determining that the flexible direct current power transmission system enters a fault ride-through state based on a grid-connected point voltage or a phase-locked loop output frequency; in the fault ride-through state, real-time detecting a change amount of the phase-locked loop output frequency, dynamically adjusting an integral coefficient of the phase-locked loop according to an amplitude of the change amount to obtain a target integral coefficient; judging whether the phase-locked loop has a mathematical sense balance point according to a d-axis component and a q-axis component of a grid current, a grid voltage and system impedance, if it is judged that the balance point is lost, switching a d-axis reference value and a q-axis reference value of a current inner loop into preset improved reference values respectively; and performing fault control on the flexible direct current power transmission system according to the target integral coefficient and the improved reference values, so that the application can improve the efficiency of transient stability under a serious voltage drop fault of the flexible direct current power transmission system.

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