氧化锌避雷器泄漏电流检测的优化FFT分析
|
摘要
氧化锌避雷器泄露电流检测的实现,是通过谐波分析提取全泄露电流的各次频率阻性分量,依据其变化可判断该装置在电网中的运行情况。快速傅里叶变换(FFT)算法进行谐波分析时很难做到整数周期截断和同步采样,由此引入的频谱泄露和栅栏效应会影响谐波分析的结果,采用加窗和校正算法可以改善谐波频率、幅值和相位的提取精度。选用一种利用距谐波频率点最近的幅值最大和次大的两根离散谱线的比值以修正谐波参数的比值公式校正算法,同时利用窗谱函数推导出了谐波频率、幅值和相位的修正公式。这种算法能够有效降低频谱泄露和栅栏效应以及干扰给谐波分析带来的不利影响。基于该FFT的优化算法,推导了加汉宁窗函数的实用修正公式,通过仿真比较了不同窗函数修正算法的计算精度,并在实验环境下验证了加汉宁窗的比值校正算法的有效性和易实现性,且已应用于氧化锌避雷器泄露电流检测的实际工程中,利用该校正算法精确检测泄漏电流谐波阻性分量,对氧化锌避雷器运行性能进行诊断。
The realization of the leakage current detection of the zinc oxide arrester is to extract the frequency resistive components of the full leakage current through harmonic analysis,and the operation of the device in the power grid can be judged according to the change.Fast Fourier Transform( FFT) algorithm is difficult to perform integer period truncation and synchronous sampling in harmonic analysis.The resulting spectral leakage and fence effect will affect the results of harmonic analysis. Windowing and correction algorithms can improve the accuracy of harmonic frequency,amplitude and phase calculation. In this paper,a ratio correction formula for correcting the harmonic parameters using the ratio of two discrete spectral lines closest to the harmonic frequency point is selected. At the same time,the correction formula of harmonic frequency,amplitude and phase is derived by using the window spectrum function. This algorithm can effectively reduce the spectral leakage and fence effect and the adverse effects of interference on harmonic analysis. Based on the optimization algorithm of the FFT,this paper deduces the practical correction formula of the window function of Hanning,compares the calculation precision of different window function and correction algorithm through simulation,and verifies the ratio correction algorithm of Hanning window in the experimental environment. It is effective and easy to implement,and has been applied to the actual engineering of leakage current detection of zinc oxide arresters. Using the correction algorithm to accurately detect the variation of the leakage current harmonic resistive component,and diagnose the running performance of the zinc oxide arrester.
The realization of the leakage current detection of the zinc oxide arrester is to extract the frequency resistive components of the full leakage current through harmonic analysis,and the operation of the device in the power grid can be judged according to the change.Fast Fourier Transform( FFT) algorithm is difficult to perform integer period truncation and synchronous sampling in harmonic analysis.The resulting spectral leakage and fence effect will affect the results of harmonic analysis. Windowing and correction algorithms can improve the accuracy of harmonic frequency,amplitude and phase calculation. In this paper,a ratio correction formula for correcting the harmonic parameters using the ratio of two discrete spectral lines closest to the harmonic frequency point is selected. At the same time,the correction formula of harmonic frequency,amplitude and phase is derived by using the window spectrum function. This algorithm can effectively reduce the spectral leakage and fence effect and the adverse effects of interference on harmonic analysis. Based on the optimization algorithm of the FFT,this paper deduces the practical correction formula of the window function of Hanning,compares the calculation precision of different window function and correction algorithm through simulation,and verifies the ratio correction algorithm of Hanning window in the experimental environment. It is effective and easy to implement,and has been applied to the actual engineering of leakage current detection of zinc oxide arresters. Using the correction algorithm to accurately detect the variation of the leakage current harmonic resistive component,and diagnose the running performance of the zinc oxide arrester.
引文
[1]高峰,郭洁,徐欣,等.交流金属氧化物避雷器受潮与阻性电流的关系[J].高电压技术,2009,35(11):2629-2633.GAO F,GUO J,XU X,et.al.Relation between resistive current and MOA affected with damp[J].High Voltage Engineering,2009,35(11):2629-2633.
[2]颜湘莲,王文华.氧化锌避雷器阻性电流提取算法探讨[J].电力设备,2006,7(2):62-63.YAN X L,WANG W H.Discussion on resistive current extraction algorithm of zinc oxide arrester[J].Electrical Equipment,2006,7(2):62-63.
[3]FERRERO A,SALICONE S,TOSCANI S.A fast simplified frequency-domain interpolation method for the evaluation of the frequency and amplitude of spectral components[J].IEEE Transactions on Instrumentation and Measurement,2011,60(5):1579-1587.
[4]翟晓军,周波.一种改进的插值FFT谐波分析算法[J].中国电机工程学报,2016,36(11):2952-2958.ZHAI X J,ZHOU B.An improved interpolated FFTalgorithm for harmonic analysis[J].Proceedings of the CSEE,2016,36(11):2952-2958.
[5]刘冬梅,杨重良,何怡刚,等.基于Rife-Vincent自卷积窗三谱线插值FFT电力谐波分析[J].电子测量与仪器学报,2016,30(9):1351-1355.LIU D M,YANG CH L,HE Y G,et al.Harmonic analysis of power system based on Rife-Vincent self-convolution window triple-spectral-line interpolation FFT[J].Journal of Electronic Measurement and Instrumentation,2016,30(9):1351-1355.
[6]唐求,王耀南,郭斯羽.电力系统谐波及其检测方法研究[J].电子测量与仪器学报,2009,23(5):29-33.TANG Q,WANG Y N,GUO S Y.Research on harmonics and its measurement method in power system[J].Journal of Electronic Measurement and Instrumentation,2009,23(5):29-33.
[7]刘冬梅,郑鹏,何怡刚,等.几种谐波检测加窗插值FFT算法的比较[J].电测与仪表,2013,50(12):51-55.LIU D M,ZHENG P,HE Y G,et al.Analysis and comparison of several harmonic detection methods with windows and interpolation FFT[J].Electrical Measurement&Instrumentation,2013,50(12):51-55.
[8]翟瑞淼,英超,任国臣,等.基于Nuttall窗的三峰插值谐波算法分析[J].电力系统保护与控制,2015,43(10):38-43.ZHAI R M,YING CH,REN G CH,et al.An approach for harmonic analysis based on Nuttall window and triplespectral-line interpolation[J].Power System Protection And Control,2015,43(10):38-43.
[9]温和,滕召胜,王永,等.改进加窗插值FFT动态谐波分析算法及应用[J].电工技术学报,2012,22(12):271-277.WEN H,TENG ZH SH,WANG Y,et al.Improved windowed interpolation FFT algorithm and application for power harmonic analysis[J].Transaction of China Eelctrotechnical Society,2012,22(12):271-277.
[10]高云鹏,滕召胜,温和,等.凯塞窗插值FFT的电力谐波分析与应用[J].中国电机工程学报,2010,30(4):43-48.GAO Y P,TENG ZH SH,WEN H,et al.Harmonic analysis based on Kaiser Window interpolation FFT and its application[J].Proceedings of the CSEE,2010,30(4):43-48.
[11]赵文春,马伟明,胡安.电机测试中谐波分析的高精度FFT算法[J].中国电机工程学报,2001,21(12):83-87.ZHAO W CH,MA W M,HU AN.FFT algorithm with high accuracy for harmonic analysis in the electric machine[J].Proceedings of the CSEE,2001 21(12):83-87.
[12]李志刚,汪涛,何怡刚,等.基于改进余弦窗的加窗插值FFT谐波分析[J].电气工程学报,2016,11(4):15-21.LI ZH G,WANG T,HE Y G,et.al.Harmonic analysis based on an enhanced cosine-window interpolation FFTalgorithm[J].Journal of Electrical Engineering,2016,11(4):15-21.
[13]牛胜锁,梁志瑞,张建华,等.基于三谱线插值FFT的电力谐波分析算法[J].中国电机工程学报,2012,32(16):130-132.NIU SH S,LIANG ZH R,ZHANG J H,et al.Algorithm for electrical harmonic analysis based on triple-spectrumline interpolation FFT[J].Proceedings of the CSEE,2012,32(16):130-132.
[14]刘敏,王克英.基于加窗双峰谱线插值的高精度FFT谐波分析[J].电测与仪表,2006,43(3):20-22.LIU M,WANG K Y.High accurate FFT algorithm for harmonic analysis based on window function and double peak of spectral lines interpolation[J].Electrical Measurement&Instrumentation,2006,43(3):20-22.
[15]宋鑫超,刘启明,苏庆堂.基于FFT最大谱线处相位差的频谱校正方法[J].控制工程,2017,24(5):1086-1089.SONG X CH,LIU Q M,SU Q T.Spectrum correction method based on FFT maximum spectral phase difference[J].Control Engineering of China,2017,24(5):1086-1089.
[2]颜湘莲,王文华.氧化锌避雷器阻性电流提取算法探讨[J].电力设备,2006,7(2):62-63.YAN X L,WANG W H.Discussion on resistive current extraction algorithm of zinc oxide arrester[J].Electrical Equipment,2006,7(2):62-63.
[3]FERRERO A,SALICONE S,TOSCANI S.A fast simplified frequency-domain interpolation method for the evaluation of the frequency and amplitude of spectral components[J].IEEE Transactions on Instrumentation and Measurement,2011,60(5):1579-1587.
[4]翟晓军,周波.一种改进的插值FFT谐波分析算法[J].中国电机工程学报,2016,36(11):2952-2958.ZHAI X J,ZHOU B.An improved interpolated FFTalgorithm for harmonic analysis[J].Proceedings of the CSEE,2016,36(11):2952-2958.
[5]刘冬梅,杨重良,何怡刚,等.基于Rife-Vincent自卷积窗三谱线插值FFT电力谐波分析[J].电子测量与仪器学报,2016,30(9):1351-1355.LIU D M,YANG CH L,HE Y G,et al.Harmonic analysis of power system based on Rife-Vincent self-convolution window triple-spectral-line interpolation FFT[J].Journal of Electronic Measurement and Instrumentation,2016,30(9):1351-1355.
[6]唐求,王耀南,郭斯羽.电力系统谐波及其检测方法研究[J].电子测量与仪器学报,2009,23(5):29-33.TANG Q,WANG Y N,GUO S Y.Research on harmonics and its measurement method in power system[J].Journal of Electronic Measurement and Instrumentation,2009,23(5):29-33.
[7]刘冬梅,郑鹏,何怡刚,等.几种谐波检测加窗插值FFT算法的比较[J].电测与仪表,2013,50(12):51-55.LIU D M,ZHENG P,HE Y G,et al.Analysis and comparison of several harmonic detection methods with windows and interpolation FFT[J].Electrical Measurement&Instrumentation,2013,50(12):51-55.
[8]翟瑞淼,英超,任国臣,等.基于Nuttall窗的三峰插值谐波算法分析[J].电力系统保护与控制,2015,43(10):38-43.ZHAI R M,YING CH,REN G CH,et al.An approach for harmonic analysis based on Nuttall window and triplespectral-line interpolation[J].Power System Protection And Control,2015,43(10):38-43.
[9]温和,滕召胜,王永,等.改进加窗插值FFT动态谐波分析算法及应用[J].电工技术学报,2012,22(12):271-277.WEN H,TENG ZH SH,WANG Y,et al.Improved windowed interpolation FFT algorithm and application for power harmonic analysis[J].Transaction of China Eelctrotechnical Society,2012,22(12):271-277.
[10]高云鹏,滕召胜,温和,等.凯塞窗插值FFT的电力谐波分析与应用[J].中国电机工程学报,2010,30(4):43-48.GAO Y P,TENG ZH SH,WEN H,et al.Harmonic analysis based on Kaiser Window interpolation FFT and its application[J].Proceedings of the CSEE,2010,30(4):43-48.
[11]赵文春,马伟明,胡安.电机测试中谐波分析的高精度FFT算法[J].中国电机工程学报,2001,21(12):83-87.ZHAO W CH,MA W M,HU AN.FFT algorithm with high accuracy for harmonic analysis in the electric machine[J].Proceedings of the CSEE,2001 21(12):83-87.
[12]李志刚,汪涛,何怡刚,等.基于改进余弦窗的加窗插值FFT谐波分析[J].电气工程学报,2016,11(4):15-21.LI ZH G,WANG T,HE Y G,et.al.Harmonic analysis based on an enhanced cosine-window interpolation FFTalgorithm[J].Journal of Electrical Engineering,2016,11(4):15-21.
[13]牛胜锁,梁志瑞,张建华,等.基于三谱线插值FFT的电力谐波分析算法[J].中国电机工程学报,2012,32(16):130-132.NIU SH S,LIANG ZH R,ZHANG J H,et al.Algorithm for electrical harmonic analysis based on triple-spectrumline interpolation FFT[J].Proceedings of the CSEE,2012,32(16):130-132.
[14]刘敏,王克英.基于加窗双峰谱线插值的高精度FFT谐波分析[J].电测与仪表,2006,43(3):20-22.LIU M,WANG K Y.High accurate FFT algorithm for harmonic analysis based on window function and double peak of spectral lines interpolation[J].Electrical Measurement&Instrumentation,2006,43(3):20-22.
[15]宋鑫超,刘启明,苏庆堂.基于FFT最大谱线处相位差的频谱校正方法[J].控制工程,2017,24(5):1086-1089.SONG X CH,LIU Q M,SU Q T.Spectrum correction method based on FFT maximum spectral phase difference[J].Control Engineering of China,2017,24(5):1086-1089.