配电网高阻抗故障时频检测方法的研究
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摘要
随着配电网中性点经小电阻接地的方式在我国推广,高阻抗故障的检测引起了人们的重视。由于高阻抗故障引起的故障电流较小,不能使过流保护装置产生动作,因此它的检测比较困难。在故障发生后若不及时采取有效措施,会对人的生命安全造成威胁,并有引发火灾的可能。
本课题来源于重庆大学教育部重点实验室访问学者项目,对小电阻接地配电网发生高阻抗故障时的特征及检测方法进行了研究。本文首先利用对称分量法推导了配电网发生单相接地故障时的相电压、故障点对地电流以及中性点电压与过渡电阻之间的数学表达式,比较了中性点经小电阻接地和消弧线圈接地的配电网发生单相接地故障时的特征。为了研究高阻抗故障检测方法,对一种伴随电弧的高阻抗故障以及线路的正常事件进行了仿真,获取了小电阻接地配电网单条线路的线电流样本数据。随后,采用频域分析工具FFT获取了线电流基波与谐波的幅值和相位信息,并设计了一种BP神经网络分类器对电流样本进行分类。最后,利用小波变换这种新的时频分析方法,获取了部分正常事件的特征,与基于FFT和BP神经网络的分类器相结合来降低分类器的误识别率。
仿真结果表明,基于FFT和神经网络的分类器可以区分高阻抗故障和线路的正常事件;小波变换与基于FFT和神经网络的分类器相结合的方法能够更准确的识别出电容投切、负载投切和励磁涌流等线路正常事件。
With low-resistance grounding method of distribution network being popular in China, high impedance fault detection has attracted people’s attention. Because high impedance fault doesn’t draw enough fault current to operate overcurrent protective devices, it is hard to detect it. It will threaten people’s life or even cause a fire hazard if remains undetected.
This paper is financially supported by the Visiting Scholar Program of Chongqing University, aiming to do research on the characteristics and detecting method of high impedance faults. First, the expressions of three phase voltage, fault current and neutral point voltage is derived using symmetrical components method, and the characteristics of single-phase-to-ground fault in low-resistance grounding network and compensated network are compared. Second, for detection method research, line current samples during a kind of high impedance fault accompanied with arcing and normal operations are got through simulation. Then,in frequency domain, FFT is used to get magnitude and phase information of fundamental and harmonic current, and a BP neural network is designed to classify the line current samples. Finally, wavelet transform, the new time-frequency domain analyzing tool, is used to help reduce false classification rate of the FFT and BP neural network based classifier.
Simulation results show that the FFT and BP neural network based classifier can distinguish high impedance faults from normal operations. Through combination of wavelet transform and the FFT and BP neural network based classifier, detection of normal operations such as capacitor switching, load switching and inrush current can be more accurate.
本课题来源于重庆大学教育部重点实验室访问学者项目,对小电阻接地配电网发生高阻抗故障时的特征及检测方法进行了研究。本文首先利用对称分量法推导了配电网发生单相接地故障时的相电压、故障点对地电流以及中性点电压与过渡电阻之间的数学表达式,比较了中性点经小电阻接地和消弧线圈接地的配电网发生单相接地故障时的特征。为了研究高阻抗故障检测方法,对一种伴随电弧的高阻抗故障以及线路的正常事件进行了仿真,获取了小电阻接地配电网单条线路的线电流样本数据。随后,采用频域分析工具FFT获取了线电流基波与谐波的幅值和相位信息,并设计了一种BP神经网络分类器对电流样本进行分类。最后,利用小波变换这种新的时频分析方法,获取了部分正常事件的特征,与基于FFT和BP神经网络的分类器相结合来降低分类器的误识别率。
仿真结果表明,基于FFT和神经网络的分类器可以区分高阻抗故障和线路的正常事件;小波变换与基于FFT和神经网络的分类器相结合的方法能够更准确的识别出电容投切、负载投切和励磁涌流等线路正常事件。
With low-resistance grounding method of distribution network being popular in China, high impedance fault detection has attracted people’s attention. Because high impedance fault doesn’t draw enough fault current to operate overcurrent protective devices, it is hard to detect it. It will threaten people’s life or even cause a fire hazard if remains undetected.
This paper is financially supported by the Visiting Scholar Program of Chongqing University, aiming to do research on the characteristics and detecting method of high impedance faults. First, the expressions of three phase voltage, fault current and neutral point voltage is derived using symmetrical components method, and the characteristics of single-phase-to-ground fault in low-resistance grounding network and compensated network are compared. Second, for detection method research, line current samples during a kind of high impedance fault accompanied with arcing and normal operations are got through simulation. Then,in frequency domain, FFT is used to get magnitude and phase information of fundamental and harmonic current, and a BP neural network is designed to classify the line current samples. Finally, wavelet transform, the new time-frequency domain analyzing tool, is used to help reduce false classification rate of the FFT and BP neural network based classifier.
Simulation results show that the FFT and BP neural network based classifier can distinguish high impedance faults from normal operations. Through combination of wavelet transform and the FFT and BP neural network based classifier, detection of normal operations such as capacitor switching, load switching and inrush current can be more accurate.
引文
1 C. L. Benner, B. D. Russell. Practical High-impedance Fault Detection on Distribution Feeders. IEEE Transactions on Industry Applications. 1997, 33(3):635~640
2 S. J. Huang, C. T. Hsieh. High-impedance Fault Detection Utilizing a Morlet Wavelet Transform Approach. IEEE Transactions on Power Delivery. 1999, 14(4):1401~1410
3 F. M. Uriarte. Modeling, Detection, and Localization of High-Impedance Faults in Low-Voltage Distribution Feeders. Thesis for the Master Degree of Virginia Tech Polytechnic Institute and State University. 2003 :1~10
4要焕年,曹梅月.电力系统谐振接地.中国电力出版社, 2000:2~4
5李柏良.基于小波分析的小电流接地系统单相接地故障选线.山东大学硕士学位论文. 2006 :1~2
6张利生,刘彤军,杨旭东.中压配电网中性点接地方式的选择.内蒙古电力技术. 2004 ,22(2):11
7刘明岩.配电网中性点接地方式的选择.电网技术. 2004 ,28(16):86~87
8高亚栋,杜斌等.中性点经小电阻接地配电网中弧光接地过电压的研究.高压电器, 2004, 40(5):345~348
9于立涛. 35 kV配电网中性点经小电阻接地的改造方案分析.继电器, 2004, 32(16): 57~59
10陈多.中压电网中性点接地方式分析与探讨.山西电力, 2006, 3:11~13
11戴克铭.配电系统中性点接地方式的分析.电网技术, 2000, 24(10):52~55
12平绍勋,石健. 10kV配网小电阻接地运行分析.高电压技术, 2002, 28(9): 49
13 B. M. Aucoin, R. H. Jones. High Impedance Fault Detection Implementation Issues. IEEE Transactions on Power Delivery. 1996, 11(1):139~140
14 D. l. Jeerings, J. R. Linders. Ground Resistance Revisited. IEEE Transactions on Power Delivery, 1989, 4(2):949~953
15 A. E. Emanuel, et al. High Impedance Fault Arcing on Sandy Soil in 15 kV Distribution Feeders: Contributions to the Evaluation of the Low Frequency Spectrum. IEEE Transactions on Power Delivery, 1990, 5(2):676~686
16 S. R. Nam, J. K. Park, Y. C. Kang, T. H. Kim. IEEE. A Modeling Method of aHigh Impedance Fault in a Distribution System Using Two Series Time-Varying Resistances in EMTP. Power Engineering Society Summer Meeting, Vancouver, BC, Canada, 2001:1175~1180
17 K. Y Lien, et al. Energy Variance Criterion and Threshold Tuning Scheme for High Impedance Fault Detection. IEEE Transactions on Power Delivery. 1996, 14(3):810~815
18 T. M. Lai, et al. High-Impedance Fault Detection Using Discrete Wavelet Transform and Frequency Range and RMS Conversion. IEEE Transactions on Power Delivery. 2005, 20(1):397~404
19 Y. Sheng, S. M. Rovnyak. Decision Tree-Based Methodology for High Impedance Fault Detection. IEEE Transactions on Power Delivery. 2004, 19(2):533~536
20 J. Carr. Detection of High Impedance Fault on Multi-Grounded Primary Distribution Systems. IEEE Transactions on Power Apparatus and Systems. 1981, 100(4):2008~2016
21 A. V. Mamishev, B. D. Russell, C. L. Benner. Analysis of High Impedance Faults Using Fractal Techniques. IEEE Transactions on Power Systems. 1996, 11(1):435~440
22任震.小波分析及其在电力系统中的应用.中国电力出版社, 2003:1~3
23 A. R. Sedighi, M. R. Haghifam, O. P. Malik, M. H. Ghassemian. High Impedance Fault Detection Based on Wavelet Transform and Statistical Pattern Recognition. IEEE Transactions on Power Delivery. 2005, 20(4):2414-2421
24 F. G. Jota, P. R. S. Jota. High-impedance Fault Identification Using a Fuzzy Reasoning System. IEE Proceedings online no.19982358, 1998:656~662
25 H. Mokhtari, R. Aghatehrani. A New Wavelet-Based Method for Detection of High Impedance Faults. International Conference on Future Power Systems, 2005:1~6
26国家电力调度通信中心.电力系统继电保护使用技术问答.第二版.中国电力出版社. 2000:200~202
27江文东. 10kV小电阻接地系统零序过流定值的探讨.电力自动化设备. 2002, 22(10):73~75
28匡洪海,黄少先.自适应和模糊推理结合的故障分类新方法.电力系统及其自动化学报. 2004, 16(6):38~43
29王玮,蔡伟,张元芳,樊大伟.基于阻抗法的电力电缆高阻故障定位理论及试验.电网技术. 2001, 25(11):39~41
30 C. J. Kim, B. D. Russell. High-impedance Fault Detection System Using an Adaptive Element Model. IEE Proceedings-Generation, Transmission and Distribution. 1993, 140(6):153~159
31 C. J. Kim, B. D. Russell. A Learning Method for Use in Intelligent Computer Relays for High Impedance Faults. IEEE Transactions on Power Delivery. 1991, 6(1):738~744
32 D. C. T. Wai, Yibin Xia. A novel technique for high impedance fault detection. IEEE Transactions on Power Delivery. 1998, 13(3):738~744
33倪虹妹,周军.电网中性点经电阻接地浅析.江西水利科技. 2004, 30(增刊):115~117
34贺家李,宋从矩.电力系统继电保护原理.增订版.中国电力出版社, 2004:62~63
35蒙恩.小电流接地系统单相接地的小波分析及故障选线.广西大学,硕士学位论文. 2006:46~48
36檀国彪,涂东明,陈大鹏.基于最大I·sinφ或Δ(I·sinφ)原理的微机选线装置.中国电力. 1995, 28(7):16~20
37曾祥君,尹项根,张哲,陈德树,文明浩.零序导纳馈线接地保护的研究.中国电机工程学报. 2001, 21(4):5~10
38牟龙华.零序电流有功分量方向接地选线保护原理.电网技术. 1999, 23(9):60~62
39束洪春,肖白.配电网单相电弧接地故障选线暂态分析法.电力系统自动化. 2002, 26(21):58~59
40陈奎,唐轶.小电流接地系统电弧接地选线方法的研究.继电器. 2005, 33(16):5~9
41齐郑,杨以涵.中心点非有效接地系统单相接地选线技术分析.电力系统自动化. 2004, 28(14):1~5
42 V. L. Buchholz, M. Nagpal, J. B. Neilson. R. Parsi-Feraidoonian. W. Zarechi. High Impedance Fault Detection Device Tester. IEEE Transactions on Power Delivery. 1996, 11(1):184~190
43王维俭,厚炳蕴.大型机组继电保护理论基础.水利电力出版社, 1989:55~70
44 J. R. Lucas, P. G. McLaren, W. W. L. Keerthipala, R. P. Jayasinghe. Improved Simulation Models for Current and Voltage Transformers in Relay Studies. IEEE Transactions on Power Delivery. 1992, 7(1):152~159
45束洪春,林敏.电流互感器暂态数学建模及其仿真的比较研究.电网技术. 2003, 27(4):12~14
46孙即祥.现代模式识别.国防科技大学出版社, 2002:2~3
47 R. O. Duda等.模式分类.李宏东,姚天翔等译.第2版.机械工业出版社, 2005:29~35
48胡广书.数字信号处理.第2版.清华大学出版社, 2003:119~125
49王兆安,黄俊.电力电子技术.第4版.机械工业出版社, 2006:68~69
50袁宇波,陆于平,李澄,许扬.基于附加相位判别额的自适应二次谐波励磁涌流制动方案的研究.中国电机工程学报. 2006, 26(18):19~24
51季涛,谭思圆,徐丙垠,薛永端,孙同景.基于波形分析的直流系统接地故障检测新方法.电力系统自动化. 2004, 28(22):69~72
52董长虹.Matlab神经网络与应用.国防工业出版社, 2005:65~79
53 M. T. Hagan, H. B. Demuth, M. H. Beale.神经网络设计.戴葵译.机械工业出版社, 2002: 8~13,197~198
54 K.M. Hormark, M. Stinchcombe, H. White. Multilayer Feedforward networks are universal approximators. Neural Nerworks. 1989, 2(5):359~366
55飞思科技产品研发中心.小波分析理论与MATLAB7实现.电子工业出版社, 2005:33~80
56刘涛,曾祥利,曾军.实用小波分析入门.国防工业出版社, 2006:40~100
57陈佳佳.输电线路高阻接地故障检测的新方法研究.上海交通大学,硕士学位论文. 2007:11~20
2 S. J. Huang, C. T. Hsieh. High-impedance Fault Detection Utilizing a Morlet Wavelet Transform Approach. IEEE Transactions on Power Delivery. 1999, 14(4):1401~1410
3 F. M. Uriarte. Modeling, Detection, and Localization of High-Impedance Faults in Low-Voltage Distribution Feeders. Thesis for the Master Degree of Virginia Tech Polytechnic Institute and State University. 2003 :1~10
4要焕年,曹梅月.电力系统谐振接地.中国电力出版社, 2000:2~4
5李柏良.基于小波分析的小电流接地系统单相接地故障选线.山东大学硕士学位论文. 2006 :1~2
6张利生,刘彤军,杨旭东.中压配电网中性点接地方式的选择.内蒙古电力技术. 2004 ,22(2):11
7刘明岩.配电网中性点接地方式的选择.电网技术. 2004 ,28(16):86~87
8高亚栋,杜斌等.中性点经小电阻接地配电网中弧光接地过电压的研究.高压电器, 2004, 40(5):345~348
9于立涛. 35 kV配电网中性点经小电阻接地的改造方案分析.继电器, 2004, 32(16): 57~59
10陈多.中压电网中性点接地方式分析与探讨.山西电力, 2006, 3:11~13
11戴克铭.配电系统中性点接地方式的分析.电网技术, 2000, 24(10):52~55
12平绍勋,石健. 10kV配网小电阻接地运行分析.高电压技术, 2002, 28(9): 49
13 B. M. Aucoin, R. H. Jones. High Impedance Fault Detection Implementation Issues. IEEE Transactions on Power Delivery. 1996, 11(1):139~140
14 D. l. Jeerings, J. R. Linders. Ground Resistance Revisited. IEEE Transactions on Power Delivery, 1989, 4(2):949~953
15 A. E. Emanuel, et al. High Impedance Fault Arcing on Sandy Soil in 15 kV Distribution Feeders: Contributions to the Evaluation of the Low Frequency Spectrum. IEEE Transactions on Power Delivery, 1990, 5(2):676~686
16 S. R. Nam, J. K. Park, Y. C. Kang, T. H. Kim. IEEE. A Modeling Method of aHigh Impedance Fault in a Distribution System Using Two Series Time-Varying Resistances in EMTP. Power Engineering Society Summer Meeting, Vancouver, BC, Canada, 2001:1175~1180
17 K. Y Lien, et al. Energy Variance Criterion and Threshold Tuning Scheme for High Impedance Fault Detection. IEEE Transactions on Power Delivery. 1996, 14(3):810~815
18 T. M. Lai, et al. High-Impedance Fault Detection Using Discrete Wavelet Transform and Frequency Range and RMS Conversion. IEEE Transactions on Power Delivery. 2005, 20(1):397~404
19 Y. Sheng, S. M. Rovnyak. Decision Tree-Based Methodology for High Impedance Fault Detection. IEEE Transactions on Power Delivery. 2004, 19(2):533~536
20 J. Carr. Detection of High Impedance Fault on Multi-Grounded Primary Distribution Systems. IEEE Transactions on Power Apparatus and Systems. 1981, 100(4):2008~2016
21 A. V. Mamishev, B. D. Russell, C. L. Benner. Analysis of High Impedance Faults Using Fractal Techniques. IEEE Transactions on Power Systems. 1996, 11(1):435~440
22任震.小波分析及其在电力系统中的应用.中国电力出版社, 2003:1~3
23 A. R. Sedighi, M. R. Haghifam, O. P. Malik, M. H. Ghassemian. High Impedance Fault Detection Based on Wavelet Transform and Statistical Pattern Recognition. IEEE Transactions on Power Delivery. 2005, 20(4):2414-2421
24 F. G. Jota, P. R. S. Jota. High-impedance Fault Identification Using a Fuzzy Reasoning System. IEE Proceedings online no.19982358, 1998:656~662
25 H. Mokhtari, R. Aghatehrani. A New Wavelet-Based Method for Detection of High Impedance Faults. International Conference on Future Power Systems, 2005:1~6
26国家电力调度通信中心.电力系统继电保护使用技术问答.第二版.中国电力出版社. 2000:200~202
27江文东. 10kV小电阻接地系统零序过流定值的探讨.电力自动化设备. 2002, 22(10):73~75
28匡洪海,黄少先.自适应和模糊推理结合的故障分类新方法.电力系统及其自动化学报. 2004, 16(6):38~43
29王玮,蔡伟,张元芳,樊大伟.基于阻抗法的电力电缆高阻故障定位理论及试验.电网技术. 2001, 25(11):39~41
30 C. J. Kim, B. D. Russell. High-impedance Fault Detection System Using an Adaptive Element Model. IEE Proceedings-Generation, Transmission and Distribution. 1993, 140(6):153~159
31 C. J. Kim, B. D. Russell. A Learning Method for Use in Intelligent Computer Relays for High Impedance Faults. IEEE Transactions on Power Delivery. 1991, 6(1):738~744
32 D. C. T. Wai, Yibin Xia. A novel technique for high impedance fault detection. IEEE Transactions on Power Delivery. 1998, 13(3):738~744
33倪虹妹,周军.电网中性点经电阻接地浅析.江西水利科技. 2004, 30(增刊):115~117
34贺家李,宋从矩.电力系统继电保护原理.增订版.中国电力出版社, 2004:62~63
35蒙恩.小电流接地系统单相接地的小波分析及故障选线.广西大学,硕士学位论文. 2006:46~48
36檀国彪,涂东明,陈大鹏.基于最大I·sinφ或Δ(I·sinφ)原理的微机选线装置.中国电力. 1995, 28(7):16~20
37曾祥君,尹项根,张哲,陈德树,文明浩.零序导纳馈线接地保护的研究.中国电机工程学报. 2001, 21(4):5~10
38牟龙华.零序电流有功分量方向接地选线保护原理.电网技术. 1999, 23(9):60~62
39束洪春,肖白.配电网单相电弧接地故障选线暂态分析法.电力系统自动化. 2002, 26(21):58~59
40陈奎,唐轶.小电流接地系统电弧接地选线方法的研究.继电器. 2005, 33(16):5~9
41齐郑,杨以涵.中心点非有效接地系统单相接地选线技术分析.电力系统自动化. 2004, 28(14):1~5
42 V. L. Buchholz, M. Nagpal, J. B. Neilson. R. Parsi-Feraidoonian. W. Zarechi. High Impedance Fault Detection Device Tester. IEEE Transactions on Power Delivery. 1996, 11(1):184~190
43王维俭,厚炳蕴.大型机组继电保护理论基础.水利电力出版社, 1989:55~70
44 J. R. Lucas, P. G. McLaren, W. W. L. Keerthipala, R. P. Jayasinghe. Improved Simulation Models for Current and Voltage Transformers in Relay Studies. IEEE Transactions on Power Delivery. 1992, 7(1):152~159
45束洪春,林敏.电流互感器暂态数学建模及其仿真的比较研究.电网技术. 2003, 27(4):12~14
46孙即祥.现代模式识别.国防科技大学出版社, 2002:2~3
47 R. O. Duda等.模式分类.李宏东,姚天翔等译.第2版.机械工业出版社, 2005:29~35
48胡广书.数字信号处理.第2版.清华大学出版社, 2003:119~125
49王兆安,黄俊.电力电子技术.第4版.机械工业出版社, 2006:68~69
50袁宇波,陆于平,李澄,许扬.基于附加相位判别额的自适应二次谐波励磁涌流制动方案的研究.中国电机工程学报. 2006, 26(18):19~24
51季涛,谭思圆,徐丙垠,薛永端,孙同景.基于波形分析的直流系统接地故障检测新方法.电力系统自动化. 2004, 28(22):69~72
52董长虹.Matlab神经网络与应用.国防工业出版社, 2005:65~79
53 M. T. Hagan, H. B. Demuth, M. H. Beale.神经网络设计.戴葵译.机械工业出版社, 2002: 8~13,197~198
54 K.M. Hormark, M. Stinchcombe, H. White. Multilayer Feedforward networks are universal approximators. Neural Nerworks. 1989, 2(5):359~366
55飞思科技产品研发中心.小波分析理论与MATLAB7实现.电子工业出版社, 2005:33~80
56刘涛,曾祥利,曾军.实用小波分析入门.国防工业出版社, 2006:40~100
57陈佳佳.输电线路高阻接地故障检测的新方法研究.上海交通大学,硕士学位论文. 2007:11~20