The increasing deployment of wind turbines in challenging environments has led to the prevalent issue of converter faults, which significantly affect the reliability and efficiency of wind power systems. Given the critical role that the converter plays in optimizing the wind power conversion process, detecting and identifying open-circuit fault in wind converter is essential for maintaining operational integrity and maximizing energy output. Current fault identification methods often suffer from limitations related to robustness and computational complexity, necessitating improved solutions. To address these shortcomings, this paper introduces an innovative fault identification method that integrates analysis of the direct current (DC) bus voltage and rotor current characteristics. It can accurately recognize the single and double tube faults of converter power tubes.
Firstly,Fault detection is facilitated by the fact that the DC bus voltage signal is easily accessible, independent of the load and control strategy. Extraction of DC bus voltage edge gradients using mathematical morphology as a feature to detect the occurrence of faults. Secondly, the Pearson correlation coefficients of the rotor side currents are calculated to analyze waveform characteristics. The coupling relationship between the three-phase currents is theoretically deduced, and it is proved that the Pearson correlation coefficients between the two-phase currents are significantly different under different fault conditions, enabling precise identification of the fault phase. Moreover, the location of the fault bridge arm is determined using the average value of the current, enhancing the accuracy of fault identification. Finally, the decision function is used to locate the faulty power tube and realize the fault classification.
Simulation results of the open-circuit fault model of doubly-fed wind power converter show that the proposed method in this paper can accurately determine the occurrence of faults and locate the position of power tubes. By comparing under large data sets, it is found that the proposed method improves the accuracy while maintaining a shorter detection time compared to other methods, which is more practical and reliable. The simulation results show that the wind speed fluctuation has a negligible effect on the DC bus voltage and rotor current, and no fault occurrence is detected, while the current characteristics are stabilized in the range of the fault-free case, which indicates that the proposed method can overcome the interference of wind speed fluctuation. By simulating voltage dips to model the load fluctuations, it is found that the fault detection module misjudges the occurrence of faults, and the current characteristics is small affected but similar in size. It is judged that no faults have occurred, so the fault identification module can be used as a verification of fault detection. A Gaussian white noise with a signal-to-noise ratio of 20 dB is also added to the acquired voltage and current data, and the results show that the proposed method is not disturbed by noise.
The following conclusions can be drawn from the simulation analysis: (1) Compared with existing methods, the method is not only simple and effective in calculation, but also has a higher accuracy rate. (2) The fault detection method based on mathematical morphology utilizes the DC bus voltage, which is easy to obtain data and rapid to detect, and is not affected by noise. (3) The Pearson correlation coefficient-based fault classification method classifies the rotor three-phase currents according to their waveform correlation, and the consistency of theoretical and simulation results shows that the method is effective and of practical significance, and the method has strong robustness.
卢奥煊, 季天瑶, 李梦诗, 莫春, 郑欣. 基于数学形态学和Pearson相关系数的风电变流器开路故障识别方法[J]. 电工技术学报, 0, (): 20240752-20240752.
Lu Aoxuan, Ji Tianyao, Li Mengshi, Mo Chun, Zheng Xin. Identification of Open-Circuit Fault in Wind Power Converter Based on Mathematical Morphology and Pearson Correlation Coefficient. Transactions of China Electrotechnical Society, 0, (): 20240752-20240752.
[1] 刘逸凡, 邹明, 王焱, 等. 面向海上风电仿真的永磁同步发电机电磁暂态等效建模方法[J]. 电工技术学报, 2024, 39(8): 2400-2411.
Liu Yifan, Zou Ming, Wang Yan, et al.Equivalent modeling method for electromagnetic transient of permanent magnet synchronous generator for offshore wind power simulation[J]. Transactions of China Electrotechnical Society, 2024, 39(8): 2400-2411.
[2] 潘郑楠, 邓长虹, 徐慧慧, 等. 考虑灵活性补偿的高比例风电与多元灵活性资源博弈优化调度[J]. 电工技术学报, 2023, 38(增刊1): 56-69.
Pan Zhengnan, Deng Changhong, Xu Huihui, et al.Game optimization scheduling of high proportion wind power and multiple flexible resources considering flexibility compensation[J]. Transactions of China Electrotechnical Society, 2023, 38(S1): 56-69.
[3] 谢震, 杨曙昕, 代鹏程, 等. 构网型全功率风电机组网侧变流器耦合分析及抑制策略[J]. 电工技术学报, 2023, 38(14): 3745-3758, 3768.
Xie Zhen, Yang Shuxin, Dai Pengcheng, et al.Grid-side coupling analysis and suppression strategy of grid-forming full-power wind turbines[J]. Transactions of China Electrotechnical Society, 2023, 38(14): 3745-3758, 3768.
[4] Yang Zhimin, Chai Yi.A survey of fault diagnosis for onshore grid-connected converter in wind energy conversion systems[J]. Renewable and Sustainable Energy Reviews, 2016, 66: 345-359.
[5] Liang Jinping, Zhang Ke, Al-Durra A, et al.A state-of-the-art review on wind power converter fault diagnosis[J]. Energy Reports, 2022, 8: 5341-5369.
[6] Mayilsamy G, Lee S R, Joo Y H.Open-switch fault diagnosis in back-to-back NPC converters of PMSG-based WTS via zero range value of phase currents[J]. IEEE Transactions on Power Electronics, 2024, 39(4): 4687-4703.
[7] Liang Jinping, Zhang Ke, Al-Durra A, et al.A multi-information fusion algorithm to fault diagnosis of power converter in wind power generation systems[J]. IEEE Transactions on Industrial Informatics, 2024, 20(2): 1167-1179.
[8] 尹志豪, 余典儒, 朱家峰, 等. IGBT功率模块封装失效机理及监测方法综述[J]. 电工电能新技术, 2022, 41(8): 51-70.
Yin Zhihao, Yu Dianru, Zhu Jiafeng, et al.Review of IGBT power module packaging failure mechanism and monitoring methods[J]. Advanced Technology of Electrical Engineering and Energy, 2022, 41(8): 51-70.
[9] 程亮亮. 双馈风电机组变流器故障诊断研究[D]. 北京: 华北电力大学, 2017.
Cheng Liangliang.Research on fault diagnosis of doubly-fed wind turbine converter[D]. Beijing: North China Electric Power University, 2017.
[10] Lu Bin, Sharma S K.A literature review of IGBT fault diagnostic and protection methods for power inverters[J]. IEEE Transactions on Industry Applications, 2009, 45(5): 1770-1777.
[11] 李咏秋, 徐晋, 汪可友, 等. 小型固态变压器状态监测及单管开路故障诊断数字孪生方法[J]. 电力系统自动化, 2023, 47(5): 153-161.
Li Yongqiu, Xu Jin, Wang Keyou, et al.Digital twin method for state monitoring and single-tube open-circuit fault diagnosis of small solid-state transformer[J]. Automation of Electric Power Systems, 2023, 47(5): 153-161.
[12] 陈诗灿, 林琼斌, 陈四雄, 等. 电力电子变流器故障诊断的智能方法综述[J]. 电气技术, 2019, 20(3): 6-12.
Chen Shican, Lin Qiongbin, Chen Sixiong, et al.Review on intelligence fault diagnosis in power electronic converters[J]. Electrical Engineering, 2019, 20(3): 6-12.
[13] 赵洪山, 程亮亮. 基于双线性观测器的双馈风电机组变流器功率管开路故障诊断[J]. 电力自动化设备, 2017, 37(3): 72-79.
Zhao Hongshan, Cheng Liangliang.Open-circuit fault diagnosis based on bilinear observer for converter power-switch of doubly-fed wind turbine[J]. Electric Power Automation Equipment, 2017, 37(3): 72-79.
[14] Naseri F, Schaltz E, Lu Kaiyuan, et al.Real-time open-switch fault diagnosis in automotive permanent magnet synchronous motor drives based on Kalman filter[J]. IET Power Electronics, 2020, 13(12): 2450-2460.
[15] 许水清, 黄文展, 何怡刚, 等. 基于自适应滑模观测器的中点钳位型三电平并网逆变器开路故障诊断[J]. 电工技术学报, 2023, 38(4): 1010-1022.
Xu Shuiqing, Huang Wenzhan, He Yigang, et al.Open-circuit fault diagnosis method of neutral point clamped three-level grid-connected inverter based on adaptive sliding mode observer[J]. Transactions of China Electrotechnical Society, 2023, 38(4): 1010-1022.
[16] 沈艳霞, 周文晶, 纪志成, 等. 基于小波包与SVM的风电变流器故障诊断[J]. 太阳能学报, 2015, 36(4): 785-791.
Shen Yanxia, Zhou Wenjing, Ji Zhicheng, et al.Fault diagnosis of converter used in wind power generation based on wavelet packet analysis and svm[J]. Acta Energiae Solaris Sinica, 2015, 36(4): 785-791.
[17] Yuan Yuan, Chai Yi, Qu Jianfeng, et al.Circuit fault diagnosis method of wind power converter with VMD-SVM[C] //2016 35th Chinese Control Conference (CCC), Chengdu, China, 2016: 6564-6569.
[18] Xue Z Y, Xiahou K S, Li M S, et al.Diagnosis of multiple open-circuit switch faults based on long short-term memory network for DFIG-based wind turbine systems[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2020, 8(3): 2600-2610.
[19] 张瑞成, 白晓泽, 董砚, 等. 基于SSAE-LSTM神经网络的风电变流器开路故障诊断[J]. 可再生能源, 2023, 41(3): 361-369.
Zhang Ruicheng, Bai Xiaoze, Dong Yan, et al.Wind power converter fault diagnosis based on SSAE-LSTM network[J]. Renewable Energy Resources, 2023, 41(3): 361-369.
[20] 王静, 郑小霞, 叶禹含, 等. 基于LWP和改进RF的风机变流器故障诊断[J]. 电力电子技术, 2023, 57(2): 30-33.
Wang Jing, Zheng Xiaoxia, Ye Yuhan, et al.Fault diagnosis of wind power converter based on LWP and improved RF[J]. Power Electronics, 2023, 57(2): 30-33.
[21] 朱琴跃, 于逸尘, 占岩文, 等. 基于短时傅里叶变换和深度网络的模块化多电平换流器子模块IGBT开路故障诊断[J]. 电工技术学报, 2024, 39(12): 3840-3854.
Zhu Qinyue, Yu Yichen, Zhan Yanwen, et al.IGBT open-circuit fault diagnosis of modular multilevel converter sub-module based on short-time Fourier transform and deep networks[J]. Transactions of China Electrotechnical Society, 2024, 39(12): 3840-3854.
[22] Avi\-na-Corral V, de Jesus Rangel-Magdaleno J, Barron-Zambrano J H, et al. Review of fault detection techniques in power converters: fault analysis and diagnostic methodologies[J]. Measurement, 2024, 234: 114864.
[23] 高鑫哲, 杜明星, 魏克新. 一种PWM整流器IGBT开路故障诊断方法[J]. 电气传动, 2014, 44(7): 63-67.
Gao Xinzhe, Du Mingxing, Wei Kexin.An diagnosis method for PWM rectifier IGBT open-fault[J]. Electric Drive, 2014, 44(7): 63-67.
[24] 沈艳霞, 周文晶, 纪志成, 等. 基于小波包分析的风力发电系统中变流器的故障识别[J]. 电网技术, 2013, 37(7): 2011-2017.
Shen Yanxia, Zhou Wenjing, Ji Zhicheng, et al.Fault identification of converter used in wind power generation based on wavelet packet analysis[J]. Power System Technology, 2013, 37(7): 2011-2017.
[25] 宋佩云, 肖岚, 许政. 基于电流相角的三相整流器开路故障诊断方法[J]. 电力电子技术, 2016, 50(6): 81-85.
Song Peiyun, Xiao Lan, Xu Zheng.Fault diagnosis method in three-phase rectifier based on the current phase angle[J]. Power Electronics, 2016, 50(6): 81-85.
[26] 陈栋, 刘振兴, 张晓菲. SVPWM整流器IGBT模块的故障诊断技术研究[J]. 华北电力大学学报(自然科学版), 2012, 39(4): 72-76.
Chen Dong, Liu Zhenxing, Zhang Xiaofei.Fault diagnosis of IGBT, odules for SVPWM rectifier[J]. Journal of North China Electric Power University (Natural Science Edition), 2012, 39(4): 72-76.
[29] 李辉, 杨甜, 谭宏涛, 等. 基于电压和电流特征的双馈风电变流器功率器件开路故障综合诊断[J]. 电工技术学报, 2021, 36(16): 3433-3445. Li Hui, Yang Tian, Tan Hongtao, et al. Comprehensive diagnosis of open-circuit fault for power devices of doubly-fed wind power converter based on the features of voltage and current[J]. Transactions of China Electrotechnical Society, 2021, 36(16): 3433-3445.
[27] 程亮亮, 沈伟强, 韦舒天, 等. 双馈风电机组变流器功率管开路故障诊断方法[J]. 可再生能源, 2019, 37(11): 1691-1696. Cheng Liangliang, Shen Weiqiang, Wei Shutian, et al. Open switch fault diagnostic method of converters for doubly fed wind turbine[J]. Renewable Energy Resources, 2019, 37(11): 1691-1696.
[28] 许水清, 陶松兵, 何怡刚, 等. 基于相电流瞬时频率估计的永磁直驱风电变流器开路故障诊断[J]. 电工技术学报, 2022, 37(2): 433-444. Xu Shuiqing, Tao Songbing, He Yigang, et al. Open-circuit fault diagnosis for back-to-back converter of PMSG wind generation system based on estimated instantaneous frequency of phase current[J]. Transactions of China Electrotechnical Society, 2022, 37(2): 433-444.
[29] 李辉, 杨甜, 谭宏涛, 等. 基于电压和电流特征的双馈风电变流器功率器件开路故障综合诊断[J]. 电工技术学报, 2021, 36(16): 3433-3445. Li Hui, Yang Tian, Tan Hongtao, et al. Comprehensive diagnosis of open-circuit fault for power devices of doubly-fed wind power converter based on the features of voltage and current[J]. Transactions of China Electrotechnical Society, 2021, 36(16): 3433-3445.
[30] Wu B Q H, Lu Z, Ji T Y. Protective relaying of power systems using mathematical morphology[M]. London: Springer, 2009.