EHV (extra-high voltage) DC grounding electrode circuit insulation coordination method

Abstract

The invention discloses an insulation coordination method for a UHV DC grounding electrode line. Including the following specific steps: step 1, select the arc angle gap value according to the operating overvoltage level; step 2, select the arc angle gap value according to the arc extinguishing ability; step 3, comprehensively select the gap according to the operating overvoltage level and arc extinguishing ability Based on the conclusion, the final arc angle configuration results are proposed. The design scheme of this method comprehensively considers the overvoltage along the UHV DC grounding electrode line and the arc extinguishing ability of the arcing angle, and uses the intersection method of the volt-ampere characteristic curve to determine the arcing angle gap value, which meets the insulation coordination requirements of the UHV DC grounding electrode line. , avoiding the technical problems of overvoltage breakdown of the UHV DC grounding electrode line and the inability to extinguish the arc due to DC freewheeling, and improving the operational reliability of the UHV DC grounding electrode line.

Description

technical field [0001] The invention relates to the field of insulation coordination of UHV DC grounding pole lines, and more specifically relates to a method for insulation coordination of UHV DC grounding pole lines. Background technique [0002] The DC earth return system (ground electrode and ground electrode line) is one of the important components of the DC transmission system. The operation mode of the DC transmission system is flexible and diverse, and the working mode of the ground electrode is also different. In the single-pole ground return line operation mode, all the conveying current of the running pole flows into the earth through the grounding pole. In order to reduce the impact of the inflow current on the power equipment of the converter station, the ground electrode is generally arranged at a position far away from the converter station. The ground electrode line is the line connecting the converter station and the ground electrode (usually an overhead l...

AI Technical Summary

Problems solved by technology

[0012] The purpose of the present invention is to overcome the shortcomings of the above-mentioned background technology, and to provide a method for insulation coordination of UHV DC grounding pole lines, and to provide a differentiated The insulation configuration scheme effectively solves the problems of operation overvoltage breakdown and lightning DC freewheeling arc extinguishing

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