Method for evaluating maximum economic dimension coefficient of grounding device under horizontal layered soil

Abstract

The invention discloses a method for evaluating a maximum economic dimension coefficient of a grounding device under horizontal layered soil. The method comprises the steps of: building a device for testing the maximum economic dimension coefficient of the grounding device under the horizontal layered soil; according to an evaluation step, applying a transient voltage to a test grounding device byusing a transient voltage generator, and measuring and recording transient voltage wave front time; and calculating and evaluating the maximum economic dimension coefficient of the grounding device under the horizontal layered soil according to the transient voltage wave front time and a soil environment where the test grounding device is located. According to the method, the transient process that transient current flows into the ground along the grounding device when the grounding device is struck by lightning in the horizontal layered soil environment can be accurately simulated, the testdevice can accurately and effectively measure and record the transient voltage wave front time, and the method can be used for accurately and effectively evaluating the maximum economic dimension coefficient of the grounding device under the horizontal layered soil.

Description

technical field [0001] The invention belongs to the technical field of electric power system grounding, in particular to a method for evaluating the maximum economic size coefficient of a grounding device under horizontal layered soil. Background technique [0002] In my country, since most of the regions are located in the temperate zone or subtropical zone, thunderstorms are more frequent. Most of the overhead transmission lines in the power system are located in the wild. In order to meet the safety distance between the lines and the ground, the towers of the overhead transmission lines are designed to be relatively high, basically at the commanding heights in the surrounding environment, and some towers are even located on the top of the mountain or On the ridge, it is extremely vulnerable to lightning strikes. In order to reduce the occurrence of line lightning tripping accidents, it is necessary to carry out lightning protection. The more common method is to design di...

AI Technical Summary

Problems solved by technology

However, during a lightning strike, the performance of the grounding device may be quite different. Most of the lightning current may flow into the ground through only a small part of the grounding device, and only a part of the grounding device plays a major role in the entire flow process, while the rest The effect is small, which means that the grounding device has the largest economic size for the effect of blocking lightning current. After exceeding this size value, it will seriously reduce the economic efficiency of lightning protection

Although considerable work has been done in this area, there is still no consensus on how to apply existing knowledge to the design of grounding devices for better high frequency and dynamic performance

Images