Research On Application Of Insulation On-line Monitoring Technique In DEYANG WULIDUI 220kV Transformer Substation

In order to practically develop the on-line monitoring technique of gas solved in oil and dielectric loss, this paper studies the application of insulation on-line monitoring system in DEYANG WULIDUI 220kV transformer substation.This paper researches the harmonic analysis method as a digitalized measurement method of dielectric loss of transformer bushing, and tests it practically. This paper also analyzes the principle and realizing method of gas solved in oil on-line monitoring.The selection of signal sensor is the key to implement hardware circuit. It designs signal program-controlled amplifying circuit, frequency-tricking circuit, data sampling and keeping circuit. The choose of 12 bits high accuracy A/D integrated data sampling card makes program simply, high flexible and expandable.The system analyzed in this paper has been on site tested. It shows high efficiency, stability and accuracy to on-line monitor dielectric loss, leaking current and equivalent capacitance for transformer bushing. And so dose the gas solved ir oil on-line monitoring system, in a word, it can be considered as the reference to diagnose the insulation status of transformer.