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Transformer Winding Condition Detection Based on Image Segmentation and Wavelet Ridges |
Zhang Miaobin1, Wang Fenghua1, Jin Yuqi2, Jin Lingfeng2, Yang Zhi2, Zhan Jiangyang2 |
1. Department of Electrical Engineering Shanghai Jiaotong University Shanghai 200240 China; 2. Stage Grid Zhejiang Electric Power Research Institute Hangzhou 310014 China |
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Abstract The construction of a new power system poses increasing requirements for the safe and reliable operation of electrical equipment and power grids. As one of the essential pieces in a power system, it is important to effectively detect the winding condition of the transformer with high accuracy. Vibrational signals of an operated transformer always carry abundant information about transformer winding and have served as an important indicator for describing winding conditions. However, the vibration monitoring method has the potential blurry fault patterns in the vibration signals caused by the limitations of the time-frequency methods and the noises from sensors. It is still arduous to accurately identify the transformer's winding condition under sudden short-circuit currents. This paper introduces the image segmentation technique to analyze the vibration signals of power transformers with the extraction of wavelet ridges. Specially, the continuous wavelet transform is applied to construct the wavelet coefficient modulus matrix. Here, the complex Morlet wavelet function with bandwidth and center frequency of 4 is selected. With the gray treatment of the wavelet coefficient modulus matrix, the maximum inter-class variance method is selected to perform the image segmentation on the wavelet coefficient modulus matrix for the detailed description of the key regions. The second segmentation is further made with the proper selection of the segment threshold. After the element extraction in each region of the wavelet coefficient modulus matrix with the mode maximum method, the wavelet ridge matrix is constructed through the polynomial fitting of the maximum element coordinates. Finally, the wavelet ridge feature vector angle (WRFVA) index is defined to evaluate the condition of the transformer winding. This method can ensure the accuracy and clarity of the obtained wavelet ridges, and the defined WRFVA index can effectively capture the vibration signal variations to judge the winding condition of the transformer. A simulated signal mainly comprises multiple cosine components with a primary frequency of 100 Hz. The calculated results show that the wavelet time-frequency graph has a high resolution in the energy concentrations, which helps distinguish the target signal from noise. In addition, the vibration signals during the multiple short-circuit impulse tests on a 110 kV three-winding power transformer are analyzed. There is a noticeable increase in vibration amplitude at the 100 Hz component with the increase of short-circuit current, accompanied by the increase of high-frequency components with different degrees. Furthermore, the WRFVA of the vibration signals decreases with the increase of short-circuit impulse currents. The distribution of wavelet ridge in the time-frequency graph can be described, and the winding condition variation with high efficiency can be illustrated. In conclusion, the proposed method based on image segmentation for the wavelet ridge extraction of vibration signal and winding condition assessment reveals several key findings. (1) The grayscale threshold obtained through the maximum between-class variance method facilitates effective image segmentation. Regions corresponding to major frequency components can be accurately identified and extracted, eliminating the background noise. (2) The wavelet ridges extracted through the image segmentation have a high time-frequency resolution, sensitively reflecting the changes in vibration signals and mechanical condition variations of the transformer winding. (3) The defined WRFVA index, which reflects the wavelet ridge distribution in time and frequency domains, exhibits noticeable changes with the degradation of transformer windings. When the variation of WRFVA exceeds 2 degrees under the same short-circuit current, it indicates the presence of slight loosening or deformation in the winding. It is suggested that the winding condition of the transformer needs to be considered at this time.
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Received: 21 November 2023
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[1] 甘益明, 王昱乾, 黄畅, 等. “双碳”目标下供热机组深度调峰与深度节能技术发展路径[J]. 热力发电, 2022, 51(8): 1-10. Gan Yiming, Wang Yuqian, Huang Chang, et al.Development path of deep peak-shaving and deep energy conservation technology for cogeneration units with “dual carbon” target[J]. Thermal Power Generation, 2022, 51(8): 1-10. [2] 付豪, 杨星磊, 张斌, 等. 考虑大规模新能源接入的变压器热寿命损失分析[J]. 电力科学与技术学报, 2020, 35(6): 53-60. Fu Hao, Yang Xinglei, Zhang Bin, et al.Analysis of transformer thermal life loss considering large-scale new energy resources access[J]. Journal of Electric Power Science and Technology, 2020, 35(6): 53-60. [3] 刘云鹏, 李欢, 田源, 等. 基于分布式光纤传感的绕组变形程度检测[J]. 电工技术学报, 2021, 36(7): 1347-1355. Liu Yunpeng, Li Huan, Tian Yuan, et al.Winding deformation detection based on distributed optical fiber sensing[J]. Transactions of China Electro- technical Society, 2021, 36(7): 1347-1355. [4] Martin D, Marks J, Saha T.Survey of Australian power transformer failures and retirements[J]. IEEE Electrical Insulation Magazine, 2017, 33(5): 16-22. [5] 陈家佳, 纪冬梅. 变压器绕组故障振动监测的研究现状[J]. 上海电力大学学报, 2020, 36(5): 495-499. Chen Jiajia, Ji Dongmei.Research status of trans- former winding fault vibration monitoring[J]. Journal of Shanghai University of Electric Power, 2020, 36(5): 495-499. [6] 邹德旭, 陈宇民, 钱国超, 等. 一起带平衡绕组的220kV主变损坏案例分析[J]. 变压器, 2019, 56(9): 78-79. Zou Dexu, Chen Yumin, Qian Guochao, et al.Case analysis of a 220kV main transformer damage with balanced winding[J]. Transformer, 2019, 56(9): 78-79. [7] 张冰倩, 咸日常, 朱锋, 等. 一起110kV变压器绕组变形故障的案例分析[J]. 变压器, 2021, 58(2): 69-73. Zhang Bingqian, Xian Richang, Zhu Feng, et al.Case analysis of 110kV transformer winding deformation fault[J]. Transformer, 2021, 58(2): 69-73. [8] 王丰华, 胡徐铭, 钱勇, 等. 变压器绕组振动监测技术研究综述[J]. 广东电力, 2018, 31(8): 52-61. Wang Fenghua, Hu Xuming, Qian Yong, et al.Research and review on monitoring technology for transformer winding vibration[J]. Guangdong Electric Power, 2018, 31(8): 52-61. [9] 律方成, 汪鑫宇, 王平, 等. 基于振动偏离及加权熵的多次短路冲击下变压器绕组机械形变辨识[J]. 电工技术学报, 2023, 38(11): 3022-3032. Lü Fangcheng, Wang Xinyu, Wang Ping, et al.Mechanical deformation identification of transformer winding under multiple short-circuit impacts based on vibration deviation and weighted entropy[J]. Transa- ctions of China Electrotechnical Society, 2023, 38(11): 3022-3032. [10] 赵妙颖, 许刚. 基于经验小波变换的变压器振动信号特征提取[J]. 电力系统自动化, 2017, 41(20): 63-69, 91. Zhao Miaoying, Xu Gang.Feature extraction for vibration signals of power transformer based on empirical wavelet transform[J]. Automation of Electric Power Systems, 2017, 41(20): 63-69, 91. [11] 赵莉华, 丰遥, 谢荣斌, 等. 基于交叉小波的变压器振动信号幅频特征量提取方法[J]. 高电压技术, 2019, 45(2): 505-511. Zhao Lihua, Feng Yao, Xie Rongbin, et al.Amplitude and frequency feature extraction for transformer vibration based on cross-wavelet transform[J]. High Voltage Engineering, 2019, 45(2): 505-511. [12] 杜厚贤, 刘昊, 雷龙武, 等. 基于振动信号多特征值的电力变压器故障检测研究[J]. 电工技术学报, 2023, 38(1): 83-94. Du Houxian, Liu Hao, Lei Longwu, et al.Power transformer fault detection based on multi- eigenvalues of vibration signal[J]. Transactions of China Electrotechnical Society, 2023, 38(1): 83-94. [13] 钱国超, 邹德旭, 于虹, 等. 电力变压器振动频谱特征值在绕组变形检测中的应用[J]. 云南电力技术, 2017, 45(4): 94-97. Qian Guochao, Zou Dexu, Yu Hong, et al.Study on spectrum eigenvalues of transformer vibration and its application on winding deformation detecting[J]. Yunnan Electric Power, 2017, 45(4): 94-97. [14] 张坤, 王丰华, 廖天明, 等. 应用复小波变换检测突发短路时的电力变压器绕组状态[J]. 电工技术学报, 2014, 29(8): 327-332. Zhang Kun, Wang Fenghua, Liao Tianming, et al.Detection of transformer winding deformation under sudden short-circuit impact based on complex wavelet algorithm[J]. Transactions of China Electrotechnical Society, 2014, 29(8): 327-332. [15] 潘超, 陈祥, 蔡国伟, 等. 基于小波包尺度-能量占比的变压器三相不平衡绕组振动特征辨识[J]. 仪器仪表学报, 2020, 41(4): 129-137. Pan Chao, Chen Xiang, Cai Guowei, et al.Identification of winding vibration characteristics of three-phase unbalanced transformer based on scale- energy ratio of wavelet packet[J]. Chinese Journal of Scientific Instrument, 2020, 41(4): 129-137. [16] Zhao Hongshan, Xu Fanhao, Xu Wenqi, et al.Feature extraction method of transformer vibration based on ensemble empirical mode decomposition subband[C]// 2016 IEEE International Conference on Power System Technology, Wollongong, NSW, Australia, 2016: 1-6. [17] 尚海昆, 许俊彦, 李宇才, 等. CEEMDAN在变压器振动信号提取中的应用[J]. 控制理论与应用, 2022, 39(3): 459-468. Shang Haikun, Xu Junyan, Li Yucai, et al.Appli- cation of CEEMDAN in vibration signal extraction of transformer[J]. Control Theory & Applications, 2022, 39(3): 459-468. [18] 顾仲翔, 马宏忠, 张勇, 等. 基于VMD与优化SVM的变压器绕组松动缺陷振动信号诊断方法[J]. 高压电器, 2023, 59(1): 117-125. Gu Zhongxiang, Ma Hongzhong, Zhang Yong, et al.Vibration signal diagnosis method of transformer winding looseness defect based on VMD and optimized SVM[J]. High Voltage Apparatus, 2023, 59(1): 117-125. [19] 赵莉华, 徐立, 刘艳, 等. 基于点对称变换与图像匹配的变压器机械故障诊断方法[J]. 电工技术学报, 2021, 36(17): 3614-3626. Zhao Lihua, Xu Li, Liu Yan, et al.Transformer mechanical fault diagnosis method based on sym- metrized dot patter and image matching[J]. Transactions of China Electrotechnical Society, 2021, 36(17): 3614-3626. [20] 黄杨, 张广斌, 王潜, 等. 基于图像特征的输电线路故障行波存续性判别[J]. 电工技术学报, 2023, 38(5): 1339-1352. Huang Yang, Zhang Guangbin, Wang Qian, et al.Identification of the existence and persistence of faulted traveling waves for transmission lines based on image features[J]. Transactions of China Elec- trotechnical Society, 2023, 38(5): 1339-1352. [21] 刘鑫, 贾云献, 苏小波, 等. 基于灰度图像纹理分析的柴油机失火故障特征提取[J]. 振动与冲击, 2019, 38(2): 140-145. Liu Xin, Jia Yunxian, Su Xiaobo, et al.Fault feature extraction for diesel engine misfires based on the gray image texture analysis[J]. Journal of Vibration and Shock, 2019, 38(2): 140-145. [22] 郝勇, 刘尚宗, 吴文辉. 振动图像结合CNN的轴承振动信号分析方法研究[J]. 机械科学与技术, 2022, 41(12): 1943-1949. Hao Yong, Liu Shangzong, Wu Wenhui.Research on bearing vibration signal analysis method combining vibration image and CNN[J]. Mechanical Science and Technology for Aerospace Engineering, 2022, 41(12): 1943-1949. [23] 卢欣欣, 马骏, 张英聪. 基于连续小波变换和无模型元学习的小样本汽车行星齿轮箱故障诊断[J]. 机械传动, 2022, 46(9): 159-164, 176. Lu Xinxin, Ma Jun, Zhang Yingcong.Fault diagnosis of small sample automobile planetary gearboxes based on continuous wavelet transform and model agnostic meta learning[J]. Journal of Mechanical Transmission, 2022, 46(9): 159-164, 176. [24] 刘景良, 郑锦仰, 郑文婷, 等. 基于改进同步挤压小波变换识别信号瞬时频率[J]. 振动测试与诊断, 2017, 37(4): 814-821, 848. Liu Jingliang, Zheng Jinyang, Zheng Wenting, et al.Instantaneous frequency identification of signals based on improved synchrosqueezing wavelet trans- form[J]. Journal of Vibration, Measurement & Diagnosis, 2017, 37(4): 814-821, 848. [25] 刘景良, 任伟新, 王超, 等. 基于最大坡度法提取非平稳信号小波脊线和瞬时频率[J]. 工程力学, 2018, 35(2): 30-37, 46. Liu Jingliang, Ren Weixin, Wang Chao, et al.Wavelet ridge and instantaneous frequency extraction based on maximum gradient method[J]. Engineering Mechanics, 2018, 35(2): 30-37, 46. [26] 周莉莉, 姜枫. 图像分割方法综述研究[J]. 计算机应用研究, 2017, 34(7): 1921-1928. Zhou Lili, Jiang Feng.Survey on image segmentation methods[J]. Application Research of Computers, 2017, 34(7): 1921-1928. [27] 吴掬鸥, 袁晓桂. 基于阈值分割技术的图像分割法研究[J]. 现代电子技术, 2016, 39(16): 105-107. Wu Juou, Yuan Xiaogui.Study on image segmentation method based on threshold segmentation tech- nology[J]. Modern Electronics Technique, 2016, 39(16): 105-107. [28] 张龙, 宋成洋, 邹友军, 等. 基于Renyi熵和K-medoids聚类的轴承性能退化评估[J]. 振动与冲击, 2020, 39(20): 24-31, 46. Zhang Long, Song Chengyang, Zou Youjun, et al.Bearing performance degradation assessment based on Renyi entropy and K-medoids clustering[J]. Journal of Vibration and Shock, 2020, 39(20): 24-31, 46. |
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