A Small Current Grounding Wire Selection and Tuning Method Based on the Access Control of Arc Suppression Coils for Short-time Abnormal Signals

Abstract

The invention discloses a small current grounded line gating and tuning method based on an arc suppression coil access control short time heteromorphic signal. The method comprises the following steps: (1) carrying out extraction and grounded line gating on the arc suppression coil access control short time heteromorphic signal; (2) preferentially tuning the faulted gated grounded line along with the arc suppression coil; and (3) putting the arc suppression coil into operation, compensating for capacitance current of a fault point, and extinguishing an electric arc. The method disclosed by the invention has the advantages that in the step (1), the arc suppression coil is not accessed into a power system, and the grounded line is gated and a tuning device is used for rapidly acquiring and analyzing voltage and current signals of the power system when the power system has a single phase grounded fault, so that the grounded faulted line is accurately selected; and in the step (2), the rated zero sequence capacitance current ICn0N of each line of the system is calculated in advance and stored in a designated database, the total rated zero sequence capacitance current ICsigma0N of the line is calculated by utilizing the data obtained by acquiring and analyzing after a fault and combining the line gating result and the data in the database, so as to take ICsigma0N and a reasonable tuning coefficient as a basis for calculating a tuning work point of the arc suppression coil, and then the arc suppression coil is correctly tuned.

Description

technical field [0001] The invention belongs to the technical field of power system automation, and is a power system control and fault detection technology, which is suitable for solving the problem of ground fault line selection and arc suppression coil tuning in a small current grounded power system whose neutral point is grounded through an arc suppression coil. Specifically, it relates to a small-current grounding line selection and tuning method based on arc-suppression coil access control for short-term abnormal signals. Background technique [0002] my country's power distribution system mainly adopts the low-current grounding operation mode in which the neutral point is not grounded or the arc-suppression coil is grounded. The urban 35kV and below distribution network mainly adopts the method of grounding the neutral point through the arc suppression coil. The biggest advantage of the low-current grounding method is that when a single-phase ground fault occurs in t...

AI Technical Summary

Problems solved by technology

In fact, when the compensation degree of the arc suppression coil in the project is not ideal, the zero-sequence current increment of the grounding line is not necessarily the largest, and because there is always a transition resistance at the grounding point, the zero-sequence current of the non-fault line also changes

Therefore, this method also has a relatively large defect in the principle of line selection.

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