交联聚乙烯电缆局部放电脉冲高灵敏度检测方法研究  

Study on High Sensitivity Detection of Partial Discharge Pulse in XLPE Cable

作　　者：周涛[1] 曾祥君[1] 

机构地区：[1]长沙理工大学电气与信息工程学院,长沙410076

出　　处：《高压电器》2013年第5期26-30,共5页High Voltage Apparatus

基　　金：湖南省自然科学基金资助项目(10jj5059)~~

摘　　要：监测局部放电是判断交联聚乙烯(XLPE)电缆绝缘状态的重要手段,受局放脉冲在电缆中传播衰变与电磁干扰的影响,电缆局放检测灵敏度难以满足电缆绝缘监测要求。为提高局放检测灵敏度,笔者利用双耦合Duffing振子系统的瞬态同步突变现象对脉冲激励十分敏感,而对白噪声具有免疫力的特点,将这一现象应用于电缆局放脉冲检测。根据电缆局放脉冲的时频域特征,构建了适用于电缆局放脉冲检测的双耦合Duffing混沌振子检测模型,确定了振子耦合系数、周期策动力的周期和幅值、振子系统的初始值;通过计算双耦合振子的最大横向Lyapunov指数来判断振子间的同步状态,以振子的同步误差检测微弱局放脉冲信号。仿真及实验结果表明,基于双耦合Duffing振子系统瞬态同步突变的处理方法能有效抑制白噪声,检测幅值十分微弱的局放脉冲,提高了局放脉冲信号的检测灵敏度。Partial discharge （PD）monitoring is an important method for evaluating the XLPE cable insulation state. Because of the PD pulse propagation decay in the cable and electromagnetic interference,the PD detection sensitivity is difficult to satisfy the monitoring requirements. In order to improve the PD detection sensitivity,the double coupled Duffing oscillator system has been used to detect the PD pulse for XLPE cable,which is very sensitive to the pulse excitation,and immunity to the white noise. According to the PD time domain and frequency domain characteristics,the especial coupled Duffing oscillator model for the cable＇s partial discharge detecting has been constructed,include the coupling coefficient of the coupled Duffing oscillator,the period and amplitude of the periodic driving force and initial value. Calculating the maximum transverse Lyapunov exponents of double coupled oscillators to judge synchronization between the oscillators,using the synchronization error of the coupled Duffing oscillators to detect PD pulse signal. The simulation and experimental results show that based on the transient synchronization mutation phenomenon of the coupled Duffing oscillator system,the processing method can effecti- vely suppress the white noise, detect the weak PD pulses and greatly improve the PD pulse detection sensitivity.

关 键 词：局部放电 交联聚乙烯电缆 Duffing混沌振子 瞬态同步突变 

分 类 号：TM855[电气工程—高电压与绝缘技术]