Method of selecting optimal phase sequence arrangement mode of one-tower double-circuit transmission line

Abstract

Provided is a method of selecting the optimal phase sequence arrangement mode of a one-tower double-circuit transmission line. According to the method, a one-tower double-circuit transmission line detailed simulation model is established based on an ATP / EMTP simulation platform, and phase sequence arrangement modes of which the negative sequence current imbalance is less than 5% are screened out according to the change in length of transmission lines. Moreover, a one-tower double-circuit transmission line outside-the-protected-area inter-phase short circuit fault model is built, the influence of the one-tower double-circuit transmission line phase sequence arrangement mode on misjudgment of a zero sequence power directional element in a relay protection device is evaluated according to transmission lines of different lengths, preferred sorting of negative sequence imbalance and preferred sorting of relay protection are comprehensively considered, and the optimal phase sequence arrangement mode is selected out. The engineering requirement that the negative sequence current imbalance of a newly-built one-tower double-circuit transmission line project should be less than 5% is met, and the problem that a zero sequence power directional element in a line protection device malfunctions due to the mode of conductor phase sequence arrangement is solved.

Description

technical field [0001] The invention relates to a method for selecting the optimal phase sequence arrangement mode of a double-circuit line on the same tower, in particular to which phase sequence arrangement mode to adopt for the transmission conductors on the double-circuit transmission line on the same tower so that the negative-sequence unbalance degree of the line satisfies A method for determining normal operation requirements and a low probability of malfunction of a relay protection device belongs to the technical field of electric power engineering. Background technique [0002] With the continuous acceleration of my country's urbanization process and the rapid growth of power loads, in order to improve the transmission capacity and power supply reliability of existing transmission lines in the case of limited land use in transmission line corridors, the same-tower double-circuit transmission technology is used in the power grid. has been widely used. However, in th...

AI Technical Summary

Problems solved by technology

It not only provides a selection method of phase sequence arrangement for new transmission line projects, but also can solve the misoperation of relay protection devices and line imbalance caused by the unreasonable phase sequence arrangement of existing double-circuit transmission lines on the same tower degree exceeds the specified limit

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