噪声影响下的高准确度介损角测量方法研究  

Study on high accurate dielectric loss angle measurement method considering noise

作　　者：温和[1,2] 王永[1] 滕召胜[1] 黄强[1] 黎福海[1] 

机构地区：[1]湖南大学电气与信息工程学院,长沙410082 [2]北京航空航天大学自动化科学与电气工程学院,北京100191

出　　处：《仪器仪表学报》2013年第4期780-785,共6页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金项目(61002035;51277058);高等学校博士学科点专项科研基金(新教师类)(20100161120004);中国博士后科学基金特别项目(2012T50033)资助

摘　　要：基于FFT的介损角检测方法易于硬件实现,但其准确度受频谱泄漏和噪声的影响较大。为此,提出了一种基于Black-man自卷积窗的高准确度介损角检测算法,建立了噪声影响下介损角检测结果的统计描述模型。首先采用Blackman自卷积窗对噪声影响下的畸变信号进行加权,其次利用离散频谱对称插值算法计算基波相位角,然后根据电压与电流基波相位差实现介损角检测,最后根据测量不确定度传播原理,推导了噪声对介损角检测准确度的统计模型,并通过仿真和实际检测2验证了本文算法和统计模型的正确性和可行性。FFT-based dielectric loss angle measurement methods can be realized easily, however its accuracy is influ- enced greatly by spectral leakage and noise. This paper presents a high-accuracy dielectric loss angle measurement method based on the Blackman self-convolution window （BSCW） , and establishes the dielectric loss measurement re- sult statistical model considering noise. Firstly, the distorted voltage and current signals are weighted using the BSCW. Then, the fundamental phases of the voltage and current signals are calculated with the discrete spectral sym- metric interpolation algorithm, and the dielectric loss angle is obtained according to the phase difference between the voltage and current fundamental phases. Finally, the statistical model of the effect of noise on dielectric loss angle measurement accuracy is deduced according to the uncertainty propagation theory. Simulation and laboratory measure- ment were carried out, and the results verify the effectiveness and practicability of the proposed method and the statis- tical model.

关 键 词：介质损耗 频谱泄漏 卷积窗 FFT 噪声 

分 类 号：TN911[电子电信—通信与信息系统] TM714[电子电信—信息与通信工程]