GIS不同耦合方式下注入脉冲的加权IMF局放信号等效性

The equivalence of weighted IMF partial discharge signals pulse injection by different coupling modes in GIS

注入脉冲模拟局放是气体绝缘金属封闭组合电器(gas insulated switchgear,GIS)特高频(ultra high frequency,UHF)局放监测装置功能校验的主要方法,由于现场校验脉冲注入的耦合方式不同,模拟局放与实际局放等效性规律尚不明确,无法保证监测装置功能校验的有效性。文中首先建立126 kV GIS典型局放缺陷(尖端、悬浮、绝缘子气泡)和内/外置式脉冲注入UHF局放检测平台,并对UHF信号有效脉冲进行归一化提取;接着提出基于经验模态分解的加权本征模函数(intrinsic mode functions,IMF)信号处理方法,通过计算局放信号欧式距离平均值和最大值表征其等效性;最后与常规信号偏差法进行对比验证。研究表明,相较于常规信号等效性分析方法,加权IMF法可有效解决UHF信号波形局部差异较大的问题;使用内置传感器脉冲注入的模拟局放信号与悬浮局放信号等效性最高,局放信号的欧式距离平均值M_(e)和最大值M_(a)分别为3.82%和10.28%。因此,UHF监测装置功能校验可采用恒定参数注入脉冲代替悬浮缺陷,且模拟局放可优先选择内置UHF传感器注入脉冲。文中研究可为UHF局放监测装置功能校验的脉冲注入方法提供参考。

Pulse injection to simulate partial discharge(PD)is the main method for functional verification of gas insulated switchgear(GIS)ultra high frequency(UHF)PD monitoring device.Due to the different coupling modes of pulse injection in field verification,the equivalence law between simulated PD and actual PD is not clear,and the effectiveness of functional verification of monitoring device cannot be guaranteed.In this paper,a typical PD defect(tip,suspension,insulator bubble)and internal/external pulse injection UHF PD detection platform for 126 kV GIS are established,and the effective pulses of UHF signals are normalized and extracted.Then a signal processing method of weighted intrinsic mode functions(IMF)based on empirical mode decomposition is proposed.The signal equivalence is characterized by calculating the average and maximum values of the Euclidean distance of the signal,and finally compared with the conventional signal deviation method.The research shows that compared with the conventional signal equivalence analysis method,the weighted IMF method can effectively solve the problem of large local difference of UHF signal waveform.The internal sensor pulse injection analog PD and suspended PD have the highest equivalence.The average value M_(e) and the maximum value M_(a) of Euclidean distance are 3.82%and 10.28%,respectively.Therefore,the function verification of UHF monitoring device can use constant parameter pulse injection instead of suspension defect,and the internal UHF sensor injection can be preferred for analog PD.The research in this paper can provide reference for the pulse injection method for the function verification of UHF PD monitoring device.