局部放电干扰评价参数信噪比的二阶估计  

Two-order Estimation of Interference Evaluation Parameter SNR on Partial Discharge

作　　者：唐炬[1] 李伟[1] 姚陈果[1] 张晓星[1] 谢颜斌[1] 

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆市沙坪坝区400044

出　　处：《中国电机工程学报》2011年第7期125-131,共7页Proceedings of the CSEE

基　　金：国家重点基础研究发展计划项目(973项目)(2009CB724506);国家优秀博士论文基金(200749)~~

摘　　要：针对实测局部放电(partial discharge,PD)信号去噪的盲目性,提出对PD信号受干扰程度先作估计评价再决定是否需要去噪的思想。运用二阶统计理论,对构造的实测PD信号相关矩阵进行奇异值分解,将得到的奇异值空间划分为代表信号能量和噪声能量的子空间,建立表征信号和噪声能量大小的判别规则,对PD信号受干扰程度评价参数信噪比(signal-to-noise ratio,SNR)进行二阶估计。通过对模拟与实测PD信号的SNR二阶估计对比分析表明,该二阶估计能很好地判断PD信号受干扰程度,为后续PD信号的去噪处理提供理论依据。It is blind that the signal process of actual partial discharge （PD） signals always is first denoised and then analyzed, and this paper proposed the idea that the signal-to-noise ratio （SNR） estimation of noise interference degree on PD source signals is first implemented and then the subsequent signal processing is carried on. 2-order statistical theory was employed to construct autocorrelation matrix of PD source signals for the singular value decomposition, to build up the rules that reflect the energy of PD signal for signal subspace and noise subspace for the estimation of the evaluation parameter SNR to actual PD source signals. By the comparative analysis from simulative PD signals and actual PD signals, the noise interference degree on PD source signals can be well estimated and evaluated, which is the theory evidence for the subsequent denoise of PD source signals.

关 键 词：电力系统 局部放电 相关矩阵 评价参数 奇异值分解 信号去噪 

分 类 号：TM835[电气工程—高电压与绝缘技术]