大型电力变压器油纸绝缘含水量的介质响应诊断技术

Moisture Content Analysis of Oil-paper Insulation for Large Power Transformers Using Dielectric Response Methods

介质响应技术是检测油纸绝缘含水量的一种无损诊断技术,该技术通过油纸绝缘的介质响应曲线判断其含水量。为推动该技术的发展和实际应用,以电介质理论为基础,对大型油纸绝缘电力变压器的介质响应特性开展了大量研究。结果表明,大型电力变压器介质响应曲线受频率、温度、含水量的影响具有较强的规律。提出了大型电力变压器油纸绝缘含水量的定性分析方法,并通过建立不同含水量、不同温度油浸纸板的复介电常数数据库及设备的X-Y模型,实现了大型电力变压器油纸绝缘含水量的定量计算,计算结果与实际基本相符。

The dielectric response technology is a nondestructive technology of moisture content diagnosis for oil-paper insulation by dielectric response curve.To promote the development and application for the dielectric response technology,the dielectric response characteristics of the actual large oil-paper insulation power transformer were studied on the basis of dielectric theory,and the test results show a strong regularity that frequency,temperature,and moisture content effect on the dielectric response curve of large power transformer.The qualitative analysis method of moisture content in oil-paper insulation for the large power transformer was proposed.The quantitative analysis method of moisture content in oil-paper insulation of the large power transformer was developed based on the equipment X-Y model and the complex permittivity database of oil impregnated pressboard under various moisture contents and temperatures,and the calculated values agree with the experimental data approximately.