Analysis and Diagnosis of Different Open-Circuit Fault Modes of Rotating Rectifier in Multi-Phase Brushless Excitation System at Nuclear Power Plant
Hao Liangliang1, Chen Jianlin1, Duan Xianwen2, He Li3, Chen Jun4
1. School of Electrical Engineering Beijing Jiaotong University Beijing 100044 China; 2. China Nuclear Power Operation Co. Ltd Shenzhen 518172 China; 3. Yangjiang Nuclear Power Co. Ltd Yangjiang 529941 China; 4. Nanjing NR Electric Co. Ltd Nanjing 211102 China
Abstract:The excitation system with a multi-phase annular brushless exciter (MPABE) is widely used in large-capacity nuclear power plants. However, the rectifier open-circuit fault caused by diodes or fuses damage often occurs in field operation. The fault types can be classified as one-tube open-circuit fault, one-phase open-circuit fault, and two-phase open-circuit fault. The actual site needs to reliably diagnose the open-circuit fault occurrence of multi-phase rotating rectifiers and accurately distinguish the fault modes. Since the field winding of the exciter is located at the stator and the rectifier rotates with the rotor at high speed, the rectifier fault cannot be monitored directly. Therefore, it is an effective way to diagnose the rotating rectifier fault using the excitation current characteristics. Hence, this paper analyzes the rectifier fault mechanism and proposes a new rectifier open-circuit fault diagnosis method based on the time-frequency characteristics of the fault excitation current. Firstly, the operation mechanism of an 11-phase annular brushless excitation system is analyzed theoretically. Based on the diode conduction sequence and the position of the fault diode in the motor operation period, the time-domain waveform of the fault excitation current is analyzed. Secondly, based on the influence mechanism of the fault diode on excitation current, the fault component of excitation current is analyzed, and the frequency-domain characteristics and spectrum distribution of one-tube open-circuit, one-phase open-circuit and two-phase open-circuit of the rotating diode are obtained. The experiments were carried out on a particular 11-phase exciter prototype. The theoretical analysis is consistent with the prototype experimental results. Finally, based on the combination of time-domain, frequency-domain, and spectrum distribution characteristics of exciter stator excitation current, a new fault diagnosis method of rotating rectifier open-circuit fault in MPABE is proposed for the rectifier one-tube open-circuit fault, one-phase open-circuit fault and two-phase open-circuit fault. The prototype experiment shows that this method can reliably identify all diode open-circuit faults of different modes. Frequency-domain characteristics indicate the occurrence of a fault. The frequency-domain characteristics of excitation current after rectifier one-phase open-circuit fault and two-phase open-circuit fault are the same, and the harmonic quantity of two-phase fault is not always greater than that of one-phase fault. However, there is a more significant difference between two-phase fault and one-phase fault in time-domain characteristics and spectrum distribution characteristics of excitation current. Therefore, this paper combines the time-domain characteristics with the frequency-domain characteristics to diagnose different faults of the rectifier. The frequency-domain characteristics activate the protection and identify the rectifier’s one-tube open-circuit fault and one-phase open-circuit fault. Then the time-domain and spectrum distribution characteristics are used to distinguish the rectifier’s two-phase open-circuit faults at different locations. The following conclusions can be drawn from the theoretical analysis and experimental results: (1) After a one-tube open-circuit fault, one period excitation current waveform contains a distortion, the corresponding frequency-domain characteristics are all integer-order harmonic currents, and the distribution characteristics of RMS are decreasing in sequence. (2) After a one-phase open-circuit fault, there are two distortions in the excitation current waveform of one period, the corresponding frequency-domain characteristics are even-order harmonic currents, and the distribution characteristic of RMS decreases in sequence. (3) After a two-phase open-circuit fault, one period of excitation current contains two or four distortions. The frequency domain is even-order harmonic currents. Regarding distribution characteristics, the 1st and 3rd phase open-circuit faults are mainly 2nd and 6th harmonic current, and the 1st and 5th phase open-circuit faults are mainly 4th harmonic current. (4) The proposed diagnosis method can reliably distinguish diode open-circuit faults of all modes.
郝亮亮, 陈建林, 段贤稳, 何力, 陈俊. 核电多相无刷励磁系统中旋转整流器不同开路故障模式的特征分析及诊断[J]. 电工技术学报, 2023, 38(18): 4932-4946.
Hao Liangliang, Chen Jianlin, Duan Xianwen, He Li, Chen Jun. Analysis and Diagnosis of Different Open-Circuit Fault Modes of Rotating Rectifier in Multi-Phase Brushless Excitation System at Nuclear Power Plant. Transactions of China Electrotechnical Society, 2023, 38(18): 4932-4946.
[1] 赵冬梅, 王浩翔, 陶然. 计及风电-负荷不确定性的风-火-核-碳捕集多源协调优化调度[J]. 电工技术学报, 2022, 37(3): 707-718. Zhao Dongmei, Wang Haoxiang, Tao Ran.A multi-source coordinated optimal scheduling model con-sidering wind-load uncertainty[J]. Transactions of China Electrotechnical Society, 2022, 37(3): 707-718. [2] 付兴贺, 江政龙, 吕鸿飞, 等. 电励磁同步电机无刷励磁与转矩密度提升技术发展综述[J]. 电工技术学报, 2022, 37(7): 1689-1702. Fu Xinghe, Jiang Zhenglong, Lü Hongfei, et al.Review of the blushless excitation and torque density improvement in wound field synchronous motors[J]. Transactions of China Electrotechnical Society, 2022, 37(7): 1689-1702. [3] 孙嘉伟, 郑泽东, 李驰, 等. 对称型多相电机断相容错运行下的电流谐波分析与补偿[J]. 电工技术学报, 2022, 37(21): 5424-5434. Sun Jiawei, Zheng Zedong, Li Chi, et al.Analysis and compensation of current harmonics in symmetrical multiphase machines in fault-tolerant operation against open-phase faults[J]. Transactions of China Electrotechnical Society, 2022, 37(21): 5424-5434. [4] Zouaghi T, Poloujadoff M.Modeling of polyphase brushless exciter behavior for failing diode oper-ation[J]. IEEE Transactions on Energy Conversion, 1998, 13(3): 214-220. [5] Jiao Ningfei, Han Xu, Wei Zhihuang, et al.Online fault diagnosis for rotating rectifier in wound-rotor synchronous starter-generator based on geometric features of current trajectory[J]. IEEE Transactions on Industrial Electronics, 2021, 68(4): 2952-2963. [6] Pang Ji, Liu Weiguo, Wei Zhihuang, et al.Online diode fault detection in rotating rectifier of the brushless synchronous starter generator[J]. IEEE Transactions on Industrial Informatics, 2020, 16(11): 6943-6951. [7] Zhang Zan, Liu Weiguo, Peng Jichang, et al.Identification of TBMES rotating diode failure[J]. IET Electric Power Applications, 2017, 11(2): 260-271. [8] Wei Zhihuang, Liu Weiguo, Pang Ji, et al.Fault diagnosis of rotating rectifier based on waveform distortion and polarity of current[J]. IEEE Transa-ctions on Industry Applications, 2019, 55(3): 2356-2367. [9] Rahnama M, Vahedi A, Alikhani A M, et al.Diode open-circuit fault detection in rectifier bridge of the brushless synchronous generator[C]//2018 XIII Inter-national Conference on Electrical Machines (ICEM), Alexandroupoli, Greece, 2018: 1821-1826. [10] Salah M, Bacha K, Chaari A, et al.Brushless three-phase synchronous generator under rotating diode failure conditions[J]. IEEE Transactions on Energy Conversion, 2014, 29(3): 594-601. [11] Wu Yucai, Cai Bochong, Ma Qianqian.Research on an online diagnosis for rotating diode faults in three-phase brushless exciter with two coils[J]. IET Electric Power Applications, 2019, 13(1): 101-109. [12] 孙宇光, 杜威, 桂林, 等. 用于多相无刷励磁机开路与短路故障检测的磁极探测线圈设计[J]. 电工技术学报, 2022, 37(14): 3542-3554. Sun Yuguang, Du Wei, Gui Lin, et al.Design of pole detection coils for open-circuit and short-circuit faults in multiphase brushless exciter[J]. Transactions of China Electrotechnical Society, 2022, 37(14): 3542-3554. [13] 吴新振, 张伟玲, 董海涛, 等. 十二相整流发电机二极管开路的故障运行分析[J]. 电工技术学报, 2017, 32(3): 157-163. Wu Xinzhen, Zhang Weiling, Dong Haitao, et al.Analysis of diode-open fault operation for 12-phase rectifier generators[J]. Transactions of China Electro-technical Society, 2017, 32(3): 157-163. [14] 孙宇光, 黄子果, 陈丽, 等. 十二相整流同步发电机定子匝间短路故障计算[J]. 电工技术学报, 2014, 29(3): 57-64. Sun Yuguang, Huang Ziguo, Chen Li, et al.Calcu-lation of stator winding inter-turn short circuit in 12-phase synchronous generators with rectifier load system[J]. Transactions of China Electrotechnical Society, 2014, 29(3): 57-64. [15] 张艳辉, 郑晓钦, 吴新振, 等. 基于有限元场路耦合的十二相整流发电机系统定子匝间短路分析[J]. 电工技术学报, 2019, 34(9): 1842-1849. Zhang Yanhui, Zheng Xiaoqin, Wu Xinzhen, et al.Analysis of stator winding inter-turn short circuit on a 12-phase rectifier generator system based on finite element field-circuit coupling[J]. Transactions of China Electrotechnical Society, 2019, 34(9): 1842-1849. [16] 郝亮亮, 张扬, 屈天龙, 等. 多相多边形无刷励磁机及旋转整流系统的运行状态分析[J]. 电力自动化设备, 2020, 40(4): 159-165. Hao Liangliang, Zhang Yang, Qu Tianlong, et al.Operating state analysis of multi-phase angular brushless exciter and rotating rectifier system[J]. Electric Power Automation Equipment, 2020, 40(4): 159-165. [17] 郝亮亮, 胡启昊, 张扬, 等. 多相环形无刷励磁系统的运行特性分析[J]. 电机与控制学报, 2021, 25(7): 30-39. Hao Liangliang, Hu Qihao, Zhang Yang, et al.Analysis of operation characteristics of multiphase annular brushless excitation system[J]. Electric Machines and Control, 2021, 25(7): 30-39. [18] Hao Liangliang, Chang Jiang, Hu Liang, et al.Analysis of the interturn short circuits of stator field windings in multiphase angular brushless exciter at nuclear power plant[J]. IEEE Transactions on Energy Conversion, 2019, 34(4): 2126-2136. [19] Hao Liangliang, Chen Jianlin, Li Jiahui, et al.Diagnosis of rotor winding short-circuit fault in multi-phase annular brushless exciter through stator field current harmonics[J]. IEEE Transactions on Energy Conversion, 2021, 36(3): 1808-1817. [20] 郝亮亮, 李佳慧, 段贤稳, 等. 核电多相环形无刷励磁机转子绕组短路故障特征分析[J]. 电工技术学报, 2020, 35(6): 1251-1261. Hao Liangliang, Li Jiahui, Duan Xianwen, et al.Analysis of short circuit fault characteristics of rotor winding of nuclear power multiphase ring brushless exciter[J]. Transactions of China Electrotechnical Society, 2020, 35(6): 1251-1261. [21] 郝亮亮, 王善铭, 邱阿瑞, 等. 多相无刷励磁系统励磁机定子电流谐波特性[J]. 清华大学学报(自然科学版), 2011, 51(1): 58-62. Hao Liangliang, Wang Shanming, Qiu Arui, et al.Harmonic characteristics of exciter stator current in multiphase brushless excitation system[J]. Journal of Tsinghua University (Science and Technology), 2011, 51(1): 58-62. [22] 郝亮亮, 王善铭, 邱阿瑞, 等. 多相无刷励磁系统旋转整流器故障的仿真与识别[J]. 电工技术学报, 2012, 27(4): 138-144. Hao Liangliang, Wang Shanming, Qiu Arui, et al.Simulation and identification of rotating rectifier fault in multiphase brushless excitation system[J]. Transa-ctions of China Electrotechnical Society, 2012, 27(4): 138-144. [23] 郝亮亮, 李佳慧, 李洪学, 等. 核电多相角形无刷励磁系统旋转二极管开路故障特征分析[J]. 电力系统自动化, 2019, 43(11): 112-120. Hao Liangliang, Li Jiahui, Li Hongxue, et al.Characteristic analysis of open-circuit fault of rotating diode in nuclear multi-phase angular brush-less excitation system[J]. Automation of Electric Power Systems, 2019, 43(11): 112-120. [24] 蔡波冲, 武玉才, 赵艳军. 基于定子电流谐波法的无刷励磁机旋转二极管开路故障检测[J]. 大电机技术, 2018(4): 61-65. Cai Bochong, Wu Yucai, Zhao Yanjun.The detection of open-circuit fault of rotary diode in brushless exciter using stator current harmonic method[J]. Large Electric Machine and Hydraulic Turbine, 2018(4): 61-65. [25] Chen Jianlin, Hao Liangliang, Wang Xiaoming, et al.Analysis of armature winding open-phase fault in multi-phase annular brushless exciter at nuclear power plant[J]. IET Electric Power Applications, 2021, 15(3): 271-283.