基于短时分数阶傅里叶变换与时频域反射法的电缆缺陷定位方法

doi:10.19595/j.cnki.1000-6753.tces.240274

摘要
图/表
参考文献
相关文章 (11)

全文: PDF (879 KB)
输出: BibTeX | EndNote (RIS)

摘要

为解决传统时频域反射法（TFDR）存在的时频分辨率低、交叉项干扰严重等问题,该文提出了一种基于短时分数阶傅里叶变换（STFRFT）与TFDR的电缆缺陷定位方法。首先,建立电力电缆的分布参数模型,研究TFDR参考信号的时频分布特征;然后,根据TFDR参考信号的频率变化系数确定STFRFT的旋转角度,获取入、反射信号的高分辨率时频分布;最后,通过入、反射信号的时频互相关函数构建电缆的缺陷定位曲线,该曲线的局部峰值指示电缆的缺陷位置。多分量参考信号的时频分布结果表明,该方法可以准确地获取入、反射信号的高分辨率时频分布,并且不存在交叉项干扰。同时,500 m电缆模型与105 m 的10 kV电力电缆的缺陷定位结果说明,该方法可以灵敏地定位电缆缺陷,且定位精度较高,相比于传统的正交匹配追踪-伪维格纳分布法、平滑伪维格纳分布法,具备更好的缺陷定位效果。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	饶显杰
	徐忠林
	丁玉琴
	胡潇予
	周凯

关键词 ：电力电缆, 缺陷定位, 时频域反射, 时频分布, 短时分数阶傅里叶变换

Abstract：

The time-frequency domain reflectometry (TFDR) method is widely used to detect and locate cable defects. However, traditional TFDR methods have problems such as low time-frequency resolution and severe cross-term interference, which make it difficult to accurately locate weak cable defects. To address these issues, this paper proposes a cable defect localization method based on short-time fractional Fourier transform (STFRFT) and TFDR. The STFRFT is used to obtain the high-resolution time-frequency distribution of the incident signal and the reflected signal, which can maintain the compact support of the signal in the time-frequency domain and eliminate cross-term interference.
Firstly, in the distributed parameter model of the power cable, the incident signal of TFDR is the Gaussian envelope linear frequency modulation signal, which can produce the reflected signal with the same time-frequency domain characteristic. So both the incident signal and the reflected signal have compact support in the time-frequency domain. Secondly, the STFRFT has a high resolution for non-stationary signals such as the linear frequency modulation signal, therefore the frequency variation coefficient of the TFDR reference signal is used to determine the rotation angle of STFRFT, which can obtain a high-resolution time-frequency distribution of the incident signal and the reflected signal. Finally, the time-frequency cross-correlation function is established as the cable defect localization curve, and the local peak of the curve shows the location of the cable defect.
The time-frequency distributions of multi-component reference signals show that, the quadratic transformation of the Wigner-Ville distribution (WVD) causes serious cross-term interference, which significantly affects the authenticity of the time-frequency distribution. The Fourier transform of synchronous squeezing transformation (SST) makes it difficult to focus the frequency domain energy of the linear frequency modulation signal, leading to the signal energy dispersion in the time-frequency distribution. The time-varying time-frequency resolution in the S-transform causes signal energy distortion in the time-frequency distribution, which weakens the compact support of the signal in the time-frequency domain. Because the STFRFT can effectively focus the signal energy in the time-frequency domain, the proposed method can accurately obtain a high-resolution time-frequency distribution of the incident signal and the reflected signal, and it can eliminate cross-term interference.
In this paper, the 500 m 10 kV power cable simulation model is established. The defect is located at 300 m, while the defect length is 1 m. Since the defect can change the characteristic impedance of the local area, this paper sets the characteristic impedance of the simulated defect area to 1.05 times that of the normal area. The local peak of the proposed defect localization curve can accurately locate the cable defect with an error of only 0.79m. In addition, the peak value of the defect is 0.98, which approaches the maximum value 1 of the curve. Meanwhile, there are no false local peaks in the proposed defect localization curve.
In the measurement process, the experimental subject is a 105 m 10 kV XLPE power cable, which has a local corrosion defect caused by water. To suppress the cross-term interference, orthogonal matching pursuit and pseudo Wigner-Ville distribution (OMP-PWVD) need to sacrifice the time-frequency resolution of the reflected signal, while smoothed pseudo Wigner-Ville distribution (SPWVD) need to sacrifice the time-frequency energy of the reflected signal. As a result, the traditional OMP-PWVD and SPWVD make it difficult to locate the local corrosion defect in the power cable. As same as the simulation results, the proposed defect localization curve can accurately locate the defect, in which the positioning error is only 0.99 m.
The conclusions of this article are summarized as follows: (1) In STFRFT, the signal can be converted to the fractional domain by rotation angle θ. Based on the time-frequency characteristics of the TFDR reference signal, the θ is set to arccot[-b/(2π)], which can effectively focus the signal energy and improve signal resolution in the time-frequency domain. (2) Compared with traditional methods, the time-frequency distribution of the STFRFT can keep the compact support of signal in the time-frequency domain and eliminate cross-term interference. (3) The defect localization results of a 500m cable model and a 105m 10kV power cable show that the proposed method can sensitively locate cable defects with a high positioning accuracy. Compared with traditional OMP-PWVD and SPWVD, the method proposed in this paper has a better defect localization result.

Key words： Power cable defect location time-frequency domain reflectometry time-frequency distribution short-time fractional Fourier transform

收稿日期: 2024-02-19

PACS:

TM41

基金资助:

国网四川省电力公司科技项目（521904230003）资助

通讯作者: 周凯男,1975年生,教授,博士生导师,研究方向为电缆绝缘状态检测与修复等。E-mail：zhoukai_scu@163.com

作者简介: 饶显杰男,1996年生,硕士,研究方向为电力设备绝缘状态监测。 E-mail：1953520244@qq.com

引用本文:

饶显杰, 徐忠林, 丁玉琴, 胡潇予, 周凯. 基于短时分数阶傅里叶变换与时频域反射法的电缆缺陷定位方法[J]. 电工技术学报, 0, (): 2492918-2492918. Rao Xianjie, Xu Zhonglin, Ding Yuqin, Hu Xiaoyu, Zhou Kai. Cable Defect Localization Method Based on Short-time Fractional Fourier Transform and Time-Frequency Domain Reflectometry. Transactions of China Electrotechnical Society, 0, (): 2492918-2492918.

链接本文:

https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.240274 https://dgjsxb.ces-transaction.com/CN/Y0/V/I/2492918

[1] 李国倡, 梁箫剑, 魏艳慧, 等. 配电电缆附件复合绝缘界面缺陷类型和位置对电场分布的影响研究[J]. 电工技术学报, 2022, 37(11): 2707-2715.
Li Guochang, Liang Xiaojian, Wei Yanhui, et al.Influence of composite insulation interface defect types and position on electric field distribution of distribution cable accessories[J]. Transactions of China Electrotechnical Society, 2022, 37(11): 2707-2715.
[2] 段玉兵, 韩明明, 王兆琛, 等. 不同热老化温度下高压电缆绝缘特性及失效机理[J]. 电工技术学报, 2024, 39(1): 45-54.
Duan Yubing, Han Mingming, Wang Zhaochen, et al.Insulation characteristics and failure mechanism of high-voltage cables under different thermal aging temperatures[J]. Transactions of China Electrotechnical Society, 2024, 39(1): 45-54.
[3] 杨朝锋, 王敏, 赵胜男, 等. 基于深度学习融合的高压电缆局部放电诊断算法研究[J]. 高压电器, 2023, 59(11): 65-73.
Yang Chaofeng), Wang Min, Zhao Shengnan, et al.Research on partial discharge diagnosis algorithm for high voltage cable based on deep learning fusion method[J]. High Voltage Apparatus, 2023, 59(11): 65-73.
[4] 单秉亮, 李舒宁, 杨霄, 等. XLPE配电电缆缺陷诊断与定位技术面临的关键问题[J]. 电工技术学报, 2021, 36(22): 4809-4819.
Shan Bingliang, Li Shuning, Yang Xiao, et al.Key problems faced by defect diagnosis and location technologies for XLPE distribution cables[J]. Transactions of China Electrotechnical Society, 2021, 36(22): 4809-4819.
[5] 饶显杰, 周凯, 黄永禄, 等. 考虑相速度频变特性的改进相位差算法局部放电定位[J]. 电工技术学报, 2021, 36(20): 4379-4388.
Rao Xianjie, Zhou Kai, Huang Yonglu, et al.Partial discharge location using improved phase difference method considering frequency-dependent characteristic of phase velocity[J]. Transactions of China Electrotechnical Society, 2021, 36(20): 4379-4388.
[6] 叶源, 胡晓. 计及双界面的电缆绝缘水树缺陷时域反射解析模型[J]. 电工技术学报, 2024, 39(1): 55-64.
Ye Yuan, Hu Xiao.A dual interface analytical model for time-domain reflectometry of water tree defects in power cables[J]. Transactions of China Electrotechnical Society, 2024, 39(1): 55-64.
[7] 任志刚, 赵雪骞, 郭卫, 等. 基于时域反射技术的电缆渗水缺陷检测方法[J]. 绝缘材料, 2022, 55(1): 80-86.
Ren Zhigang, Zhao Xueqian, Guo Wei, et al.Detecting method of cable with water seepage defect based on time domain reflection technology[J]. Insulating Materials, 2022, 55(1): 80-86.
[8] 唐作鑫, 周凯, 徐叶飞, 等. 考虑衰减补偿的频域反射单元平均恒虚警率电缆缺陷识别方法[J/OL]. 电工技术学报, 2023: 1-12[2024-02-10]. https://doi.org/10.19595/j.cnki.1000-6753.tces.230882.
Tang Zuoxin, Zhou Kai, Xu Yefei, et al. Frequency domain reflectometry cell average constant false alarm rate cable defect identification method considering attenuation compensation[J/OL]. Transactions of China Electrotechnical Society, 2023: 1-12[2024-02-10]. https://doi.org/10.19595/j.cnki.1000-6753.tces.230882.
[9] 饶显杰, 徐忠林, 陈勃, 等. 基于频域反射的电缆缺陷定位优化方法[J]. 电网技术, 2022, 46(9): 3681-3689.
Rao Xianjie, Xu Zhonglin, Chen Bo, et al.Cable defect location optimization based on frequency domain reflection[J]. Power System Technology, 2022, 46(9): 3681-3689.
[10] Kwon G Y, Lee C K, Lee G S, et al.Offline fault localization technique on HVDC submarine cable via time-frequency domain reflectometry[J]. IEEE Transactions on Power Delivery, 2017, 32(3): 1626-1635.
[11] Wang J, Stone P E C, Shin Y J, et al. Application of joint time-frequency domain reflectometry for electric power cable diagnostics[J]. IET Signal Processing, 2010, 4(4): 395.
[12] Song E, Shin Y J, Stone P E, et al.Detection and location of multiple wiring faults via time-frequency-domain reflectometry[J]. IEEE Transactions on Electromagnetic Compatibility, 2009, 51(1): 131-138.
[13] 尹振东, 王莉, 陈洪圳, 等. 增广时频域反射法在电缆复合故障检测中的应用[J]. 中国电机工程学报, 2020, 40(23): 7760-7773.
Yin Zhendong, Wang Li, Chen Hongzhen, et al.Application of augmented time frequency domain reflectometry in detection of complex cable faults[J]. Proceedings of the CSEE, 2020, 40(23): 7760-7773.
[14] 王瑶瑶, 姚周飞, 谢伟, 等. 基于时频域反射法的高温超导电缆故障定位研究[J]. 中国电机工程学报, 2021, 41(5): 1540-1547.
Wang Yaoyao, Yao Zhoufei, Xie Wei, et al.Research on fault location of high temperature superconducting cable based on time-frequency domain reflectometry[J]. Proceedings of the CSEE, 2021, 41(5): 1540-1547.
[15] 操雅婷, 周凯, 孟鹏飞, 等. 基于正交匹配-伪魏格纳分布的电缆缺陷定位[J]. 电工技术学报, 2023, 38(16): 4489-4498.
Cao Yating, Zhou Kai, Meng Pengfei, et al.Cable defect location based on orthogonal matching pursuit and pseudo Wigner-Ville distribution[J]. Transactions of China Electrotechnical Society, 2023, 38(16): 4489-4498.
[16] 彭向阳, 操雅婷, 余欣, 等.基于同步压缩变换的电缆缺陷定位研究[J/OL]. 电网技术, 2023: 1-9[2024-02-10]. https://doi.org/10.13335/j.1000-3673.pst.2023.0871.
Peng Xiangyang, Cao Yating, Yu Xin, et al.Research on cable defect location based on SST transform[J/OL]. Power System Technology, 2023: 1-9[2024-02-10]. https://doi.org/10.13335/j.1000-3673.pst.2023.0871.
[17] 刘鹏程, 田立斌, 冯杰, 等. 基于S变换与时频域反射的电缆缺陷定位方法[J]. 绝缘材料, 2023, 56(3): 47-53.
Liu Pengcheng, Tian Libin, Feng Jie, et al.Defect location method of cable based on S-transform and time-frequency domain reflectometry[J]. Insulating Materials, 2023, 56(3): 47-53.
[18] 饶显杰, 徐忠林, 龙林, 等. 基于频域反射法的电缆缺陷时域诊断特征波形[J]. 电网技术, 2023, 47(8): 3483-3493.
Rao Xianjie, Xu Zhonglin, Long Lin, et al.Cable defect time domain diagnostic characteristic waveform based on frequency domain reflection[J]. Power System Technology, 2023, 47(8): 3483-3493.
[19] 饶显杰, 周凯, 黄永禄, 等. 频域反射法中阻抗变化类型判断技术[J]. 电工技术学报, 2021, 36(16): 3457-3466.
Rao Xianjie, Zhou Kai, Huang Yonglu, et al.Type judgement technology of impedance variation in frequency domain reflection method[J]. Transactions of China Electrotechnical Society, 2021, 36(16): 3457-3466.
[20] 王昱皓, 周凯, 汪先进, 等. 基于改进时频域反射法的电力电缆局部缺陷定位[J]. 中国电机工程学报, 2021, 41(7): 2584-2594.
Wang Yuhao, Zhou Kai, Wang Xianjin, et al.Power cable defects location based on improved time-frequency domain reflectometry[J]. Proceedings of the CSEE, 2021, 41(7): 2584-2594.
[21] 李秀坤, 孟祥夏, 夏峙. 水下目标几何声散射回波在分数阶傅里叶变换域中的特性[J]. 物理学报, 2015, 64(6): 235-246.
Li Xiukun, Meng Xiangxia, Xia Zhi.Characteristics of the geometrical scattering waves from underwater target in fractional Fourier transform domain[J]. Acta Physica Sinica, 2015, 64(6): 235-246.
[22] 曹伟浩, 姚直象, 夏文杰, 等. 基于插值短时分数阶傅里叶变换-变权拟合的线性调频信号参数估计[J]. 兵工学报, 2020, 41(1): 86-94.
Cao Weihao, Yao Zhixiang, Xia Wenjie, et al.Parameter estimation of linear frequency modulation signal based on interpolated short-time fractional Fourier transform and variable weight least square fitting[J]. Acta Armamentarii, 2020, 41(1): 86-94.
[23] 饶显杰, 周凯, 谢敏, 等. 基于频域反射法的特征时域波形恢复技术[J]. 高电压技术, 2021, 47(4): 1420-1427.
Rao Xianjie, Zhou Kai, Xie Min, et al.Recovery technique of characteristic time domain waveform based on frequency domain reflection method[J]. High Voltage Engineering, 2021, 47(4): 1420-1427.