Flexible grounding power distribution network fault composite arc extinguishing method

Abstract

The invention discloses a flexible grounding power distribution network fault composite arc extinguishing method. The method comprises the following steps: firstly, screening out working conditions, such as a grounding fault phase judgment dead zone caused by a high-resistance grounding fault of an asymmetric power distribution network, which are difficult to realize reliable arc extinguishing by a voltage arc extinguishing method;secondly, according to complex grounding fault working conditions, power distribution network parameter characteristics, defining the value range of each parameter in the fault power distribution network equivalent model, obtaining differential characteristic indexes of a voltage arc extinction method and a current arc extinction method in the aspects of starting conditions, voltage and current instruction detection and synthesis, arc extinction performance evaluation and the like are obtained through the output current when the flexible grounding device works in a voltage arc extinction mode, and obtaining voltage and current arc extinction mode constraint conditions are respectively; and finally, forming a flexible grounding system composite arc extinction strategy with a voltage arc extinction method as a main method and a current arc extinction method as an auxiliary method. Reliable arc extinction under the complex grounding fault working condition is achieved.

Description

technical field [0001] The invention relates to the field of arc suppression in distribution networks, in particular to a composite arc suppression used for faults in distribution networks under complex working conditions. Background technique [0002] The distribution network goes deep into the user terminal, the operating environment is changeable, and random faults are prone to occur, of which about 70% of the faults are transient ground faults. Since the distribution network has capacitance and leakage resistance to ground, the ground fault current is capacitive current and resistive leakage current. In order to limit the ground fault current, my country's distribution network generally adopts the neutral point non-grounding operation mode, such as neutral point non-grounding, grounding through arc suppression coil, and grounding through resistance. With the development of urban and rural power grids, the capacitor current increases, the instantaneous ground fault arc s...

AI Technical Summary

Problems solved by technology

[0004] A composite arc suppression method for flexible grounding distribution network faults, characterized in that the active voltage and current arc suppression methods are reasonably selected through the active arc suppression applicability criterion, so that the active voltage arc suppression and active current The arc suppression methods are organically integrated, and the two arc suppression control methods are reasonably switched to achieve complementary advantages, and finally effectively solve the problem of reliable arc suppression in distribution networks under complex fault conditions

Images