Positive sequence capacitance measuring method for parallel circuits

Abstract

The invention relates to a positive sequence capacitance measuring method for parallel circuits, wherein positive sequence capacitance is measured by utilizing a three-phase experiment power supply and a mutual inductance measuring device. The three-phase experiment power supply is connected with a three-phase conducting wire through three connecting circuits respectively, and the mutual inductance measuring device is connected with the connecting circuits respectively through connecting branches; during measurement, a grounding knife switch at the tail end of the three-phase conducting wire is firstly opened, so that the three-phase conducting wire is insulated from the ground; grounding knife switches at the top end of the three-phase conducting wire are respectively opened, a three-phase high-pressure experiment power supply is applied, a central point of the power supply is grounded, the current of each phase, three-phase circuit voltage and three-phase active power are measured through a current transformer and a voltage transformer, and positive sequence capacitance parameters are obtained through calculation. Compared with the prior art, the method is convenient to use and simple for measurement, and the measuring results of positive sequence capacitance are coincident through detection under the condition that adjacent parallel circuits are at different grounding conditions.

Description

technical field [0001] The invention relates to a capacitance measurement method, in particular to a positive sequence capacitance measurement method of parallel lines. Background technique [0002] With the large-scale application of double (multiple) circuit lines on the same tower in my country's power grid, and the merger of large-scale line corridors, there are more and more transmission lines running in parallel on the same tower or in the same transmission channel. Although the corridors of the UHV transmission lines and the planned lines of power grids at all levels have not yet been fully determined, according to the currently determined part of the line routes, it is inevitable that the UHV AC and DC lines will use the same transmission corridor as the existing 500kV grid lines, and the parallel construction of lines will become a trend. Especially in economically developed areas, AC and DC transmission lines are becoming more and more dense, and land resources ar...

AI Technical Summary

Problems solved by technology

As the situation of power lines being erected on the same tower and crossing them becomes more and more serious, the induced voltage between transmission lines increases, which poses a serious threat to the safety of testers and instruments, and brings great pressure to the accurate measurement of line power frequency parameters. serious disturbance

In the actual work of line parameter testing, it is found that the interference voltage between transmission lines is as high as thousands of volts, and the interference voltage between the three-phase conductors of the same line is also very different.

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