Power distribution network active arc extinction device and current control method thereof

Abstract

The present invention discloses a power distribution network active arc extinction device and a current control method thereof. The device is configured to inject power current into the neutral point of a power distribution network to reach the purpose of earth fault arc extinguishing. The amplitude and the phase of the injection current may be obtained through the injection of special current into the neutral point twice and through combination of corresponding calculation methods. An injection current controller is formed by a proportion resonance controller, modulation signals are obtained by using injection current deviation signals through the proportion resonance controller, an inverter switch tube is driven after the modulation signals are subjected to triangle carrier modulation to generate inversion current, and the inversion current is outputted to the neutral point of the power distribution network after passing through a filtering circuit. The power distribution network active arc extinction device is fast in response speed, high in sensitivity and low in cost, and is able to realize rapid and reliable arc extinguishing of instant earth faults.

Description

technical field [0001] The invention belongs to the technical field of electric power system relay protection, and in particular relates to an active arc suppression device for a distribution network and a current control method thereof. Background technique [0002] The power system is a nonlinear, large-scale and complex system. The distribution network is deep into the user terminals, and the operating environment is changeable. Random faults are prone to occur, and about 70% of the faults are instantaneous ground faults. Since the distribution network has capacitance and leakage resistance to the 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 neutral point non-grounded operation modes such as neutral point grounding, arc suppressing coil grounding, and resistance grounding. With the development of urban and rural power grids, the capaciti...

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Problems solved by technology

[0004] The current distribution network fault arc suppression is generally realized by the adjustable arc suppression coil device. The device adjusts the arc suppression coil contacts to dynamically change the access capacity to perform capacitance current compensation, and it is difficult to meet the fast adjustment accuracy and response speed. Requirements for reliable arc extinguishing

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