基于回复电压曲线的油纸绝缘状态评估  

Status Assessment of Oil-paper Insulation Based on Recovery Voltage Method

作　　者：周利军[1] 李先浪[1] 王晓剑[1] 崔运光 何常新 段宗超 吴广宁[1] 

机构地区：[1]西南交通大学电气工程学院,成都610031

出　　处：《高电压技术》2014年第2期489-496,共8页High Voltage Engineering

基　　金：国家自然科学基金(51107105;51177136)~~

摘　　要：回复电压法(recovery voltage method,RVM)是诊断油纸绝缘复合电介质绝缘状态的无损方法。采用回复电压测试装置对不同的初始微水质量分数和老化程度的油纸绝缘试样进行测量,得到回复电压曲线的各个特征参量值:回复电压最大值、初始斜率和中心时间常数;为了更全面地反映油纸绝缘的老化状态,首次定义了一个新的参量:回复电压半衰期,即回复电压值在衰减到回复电压最大值一半的时刻。研究结果表明:在不同的充电电压和充放电时间比下,回复电压最大值、中心时间常数、初始斜率均与绝缘纸聚合度有良好的线性相关性。对于同一绝缘纸试样,回复电压最大值与充电电压以及充放电时间比均为正相关关系,充放电时间比对回复电压最大值的影响更显著;充放电时间比和充电电压对中心时间常数的影响不显著,中心时间常数不易受外部测试条件改变的影响,可较准确反映绝缘试样的老化状态;初始斜率随着充放电时间比的升高而增大,但受到充电电压的影响较小。回复电压半衰期随着充放电时间比的增大而升高,是反映回复电压曲线后期特性的良好特征参量,可反映油纸绝缘慢去极化过程。Recovery voltage method （RVM） is a non-destructive method for diagnosing oil-paper insulation. We measured oil-paper samples with different initial moisture contents and different aging status by using RVM, and obtained some characteristic parameter values including maximum value of return voltage, the initial slope and the central time constant. To characterize the late period information of voltage curves, we defined a new indicator, recovery voltage half-life time, i.e. the time of recovery voltage value decaying to half of the maximum. The results show that, with different charging voltages and different ratios of charging and discharging time （RCDT）, the maximum voltage, center time constant, and initial slope are linearly related to the degree of polymerization （DP） of paper. With the same paper samples, the maxi- mum voltage has a positive relationship with charging voltage and RCDT while it is more significant with RCDT. Charging voltage and RCDT slightly influence the central time constant. In fact, the central time constant is barely sus- ceptible to external test conditions, so it can accurately reflect the aging state of insulation specimen. Initial slope increases with RCDT, but it is barely affected by charging voltage. Recovery voltage half-life time increases with RCDT, and it is a good characteristic parameter reflecting the late period information of voltage curves characteristics and the slow depolarization of oil-paper insulation.

关 键 词：回复电压 油纸绝缘 充电电压 充放电时间比 介电响应 回复电压半衰期 聚合度 

分 类 号：TM855.1[电气工程—高电压与绝缘技术]