Method for distinguishing high resistance grounding failure and metallic grounding failure of power transmission line

Abstract

The invention provides a method for distinguishing the high resistance grounding failure and the metallic grounding failure of a power transmission line based on high-frequency traveling wave current. The method comprises the following steps of: sampling and measuring current on the power transmission line with a Rogowski coil to obtain grounding failure waveform data; selecting a typical effective data interval from the waveform data; carrying out Fourier frequency domain analysis on selected data; and comparing the maximum amplitude frequency with the wave form main frequency, and judging the high resistance grounding failure from the metallic grounding failure. The traditional method for recognizing failure types with power frequency voltage is always influenced by load current, line length and transition resistance. Based on the frequency features of the high frequency transient state signal of the failures, the method has the characteristic of freedom from the influence of the line load current, the line length and the transition resistance and the advantages of simpleness for judgment and easiness for realization.

Description

technical field [0001] The invention relates to a method for distinguishing a grounding fault generated when a power transmission line is struck by lightning - a high-resistance grounding fault and a metallic grounding fault. Background technique [0002] The transmission line is an important part of the power grid and an indispensable connecting element of the power system. Due to the complex and changeable natural conditions such as geological conditions and meteorological conditions in the areas it traverses, there are many factors that may cause failures, so most of the failures in the power system occur on transmission lines. Once a fault occurs, it will not only cause direct damage to the electrical equipment, affect the power supply of the system, but also often directly threaten the stability of the system. [0003] After a fault occurs on a high-voltage transmission line, it is required to accurately identify the fault type. On the one hand, this is of great signif...

AI Technical Summary

Problems solved by technology

Due to the lack of effective technical means to identify the cause of the fault, and the quality of the line inspection work is sometimes difficult to control, it is difficult to find the real cause of some accidents

This restricts the improvement of the operation and maintenance level of the transmission line, and directly affects the reliability of the safe operation of the transmission line.

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