Method for filtering unshielded measuring cable of power system

Abstract

The invention provides a method for filtering an unshielded measuring cable of a power system. The unshielded cable adopts a filtering measure at one end connected with measuring / protecting equipment. In the filtering measure, a copper mesh is tightly wound outside the unshielded cable and reliably grounded. The winding width of the copper mesh is commonly 2-3 meters according to the characteristics of an electromagnetic environment of a power plant / transformer station. The invention can filter high-frequency interference in the cable and meet the requirement of the measuring / protecting equipment of the power system on an input signal, and meanwhile, the invention also provides a novel method for reforming the unshielded cable without power-off.

Description

technical field [0001] The invention belongs to the technical field of anti-interference of unshielded measuring cables in power systems, in particular to a filtering method for unshielded measuring cables in power systems. Background technique [0002] In power plants, substations and other users who use high-current and high-voltage power equipment, it is necessary to convert high current and high voltage into lower current / voltage after passing through current transformer / voltage transformer for measurement. The cables that connect the output of the current transformer / voltage transformer to the measuring or protective equipment are called measuring cables. [0003] There are shielded cables and unshielded cables for measuring cables. Due to the complex electromagnetic environment in power plants, substations or other places with high current and high voltage, if the measurement cable uses unshielded cables (the outermost layer is an insulating layer without shielding la...

AI Technical Summary

Problems solved by technology

High-frequency interference in operation enters the measurement / protection equipment through the measurement cable, affecting the normal operation of the equipment, and even causing malfunction of the protection equipment

If there is a power failure to replace the shielded cable, it will take a long construction period, which will affect the normal production of the factory and mine, and cause relatively large economic losses. Therefore, a new method that can carry out anti-interference transformation on non-shielded cables without power failure is required.

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