Controllable Broadband Impedance Measurement Technology of Traction Power Supply System Based on Multilevel Hysteresis Current Control
Chen Siyi1,2, Hu Haitao1, Xiao Donghua1, Pan Pengyu3, Song Yitong1
1. School of Electrical Engineering Southwest Jiaotong University Chengdu 611756 China; 2. State Grid Sichuan Renshou County Electric Power Supply Branch Meishan 620500 China; 3. Electric Power Research Institute of State Grid Sichuan Electric Power Company Chengdu 610072 China
Abstract：With the increasing mileage of electrified railways and the number of new electric locomotives, the power electronics characteristics of traction power supply system in China become more and more obvious, which can easily cause wide-band oscillation phenomenon. A lot of research shows that this phenomenon is caused by the input/output characteristics mismatch of electric locomotive and traction power supply system, and this mismatch can be regarded as the impedance characteristics mismatch of “vehicle-network”. Therefore, accurately obtaining the impedance characteristics of traction power supply system is of great significance for revealing the mechanism of wide-band oscillation in electrified railway and improving the reliability of railway power supply. However, the impedance mathematical modeling method relies on the derivation of mathematical formulas, which requires to know the detailed parameters inside the system, and the traction power supply system has complex structure, numerous components, dynamic topology changes, and the actual impedance of components may deviate from the production design parameters. The impedance characteristics obtained by impedance measurement are closer to reality. Therefore, this paper focuses on the research of controllable wide-band impedance measurement technique for traction power supply system, and the main research contents are as follows: A controllable wide-band impedance measurement device embedded with energy storage unit is proposed, which mainly includes: boost transformer, cascaded H-bridge, bidirectional DC-DC converter, super capacitor. Among them, bidirectional DC-DC converter and super capacitor form energy storage unit together, which provides stable DC voltage for cascaded H-bridge to generate wide-frequency harmonic current. Its power level can be flexibly expanded by increasing the number of modules. A multilevel hysteresis current control method is proposed, which uses the characteristic that the output voltage level of each port changes with the direction of output current, combined with the calculated minimum number of modules and the current trend of error current, dynamically adjusts the output voltage of each module, limits the error current within the target range, so that the output harmonic current is as close as possible to the reference current, and improves the harmonic current output effect. Based on Matlab/Simulink, the control method is simulated and verified. Several current disturbance waveforms and Fourier analysis results with representative frequency bands are given. The simulation results show that this control method can generate wide-frequency harmonic current in the range of 10 Hz~5 kHz. A hardware-in-the-loop experimental platform is built to further verify the controllable wide-band impedance measurement device embedded with energy storage unit and multilevel hysteresis current control method. The experimental results show that the proposed method can quickly obtain the wide-band impedance characteristics of traction power supply system. The measurement range is 10 Hz~5 kHz, which greatly improves the measurement efficiency and can adapt to the measurement demand of time-varying impedance. Through the above analysis, we can draw the following conclusions: (1) The proposed device topology does not contain resistance, has low energy loss, does not need to worry about serious heating due to resistance during measurement process, and has modular structure, convenient expansion and flexible application. (2) The multilevel hysteresis current control method can inject harmonic current with controllable frequency band and amplitude into traction power supply system at one time, which can adapt to the measurement demand of time-varying impedance. (3) Compared with traditional hysteresis current control method, under the same tracking accuracy condition, this method greatly reduces switching times of power devices, avoids dead zone effect at same time, and has good application potential.
陈司懿, 胡海涛, 肖冬华, 潘鹏宇, 宋依桐. 基于多电平滞环电流控制的牵引供电系统可控宽频带阻抗测量技术[J]. 电工技术学报, 2024, 39(9): 2771-2783.
Chen Siyi, Hu Haitao, Xiao Donghua, Pan Pengyu, Song Yitong. Controllable Broadband Impedance Measurement Technology of Traction Power Supply System Based on Multilevel Hysteresis Current Control. Transactions of China Electrotechnical Society, 2024, 39(9): 2771-2783.
[1] Zhou Yi, Hu Haitao, Yang Xiaowei, et al.Low frequency oscillation traceability and suppression in railway electrification systems[J]. IEEE Transactions on Industry Applications, 2019, 55(6): 7699-7711. [2] 潘鹏宇, 胡海涛, 肖冬华, 等. 高速列车变流器“扫频式”dq阻抗测量中的频率耦合干扰机理及抑制策略[J]. 电工技术学报, 2022, 37(4): 990-999, 1009. Pan Pengyu, Hu Haitao, Xiao Donghua, et al.Frequency coupling interference mechanism and suppression strategy for frequency-sweeping-based dq impedance measurement of high-speed train converter[J]. Transactions of China Electrotechnical Society, 2022, 37(4): 990-999, 1009. [3] 袁佳歆, 曲锴, 郑先锋, 等. 高速铁路混合储能系统容量优化研究[J]. 电工技术学报, 2021, 36(19): 4161-4169, 4182. Yuan Jiaxin, Qu Kai, Zheng Xianfeng, et al.Study on capacity optimization of hybrid energy storage system for high-speed railway[J]. Transactions of China Electrotechnical Society, 2021, 36(19): 4161-4169, 4182. [4] 金程, 王小君, 姚超, 等. 基于改进禁区判据的电气化铁路车网耦合系统稳定性研究[J]. 电工技术学报, 2021, 36(21): 4459-4469. Jin Cheng, Wang Xiaojun, Yao Chao, et al.Study on stability of electrified railway vehicle-network coupling system based on improved forbidden zone criterion[J]. Transactions of China Electrotechnical Society, 2021, 36(21): 4459-4469. [5] Bakhshizadeh M K, Blaabjerg F, Hjerrild J, et al.Improving the impedance-based stability criterion by using the vector fitting method[J]. IEEE Transactions on Energy Conversion, 2018, 33(4): 1739-1747. [6] 伍文华. 新能源发电接入弱电网的宽频带振荡机理及抑制方法研究[D]. 长沙: 湖南大学, 2019. Wu Wenhua.Research on wide-bandwidth oscillation mechanism and suppression methods of renewable energy power generation connected to the weak grid[D]. Changsha: Hunan University, 2019. [7] 李亚楼, 张星, 胡善华, 等. 含高比例电力电子装备电力系统安全稳定分析建模仿真技术[J]. 电力系统自动化, 2022, 46(10): 33-42. Li Yalou, Zhang Xing, Hu Shanhua, et al.Modeling and simulation technology for stability analysis of power system with high proportion of power electronics[J]. Automation of Electric Power Systems, 2022, 46(10): 33-42. [8] 吴滨源, 李建文, 李永刚, 等. 用于谐波劣化分析的并网逆变器阻抗灰箱拟合方法[J]. 电工技术学报, 2022, 37(4): 942-953. Wu Binyuan, Li Jianwen, Li Yonggang, et al.A gray-box fitting method of grid-connected inverters impedance for the analysis of harmonic degradation[J]. Transactions of China Electrotechnical Society, 2022, 37(4): 942-953. [9] 李建文, 吴滨源, 李永刚, 等. 分析谐波劣化机理的逆变器灰箱宽频域矩阵模型及求解方法[J]. 电力系统自动化, 2020, 44(18): 155-163. Li Jianwen, Wu Binyuan, Li Yonggang, et al.Gray-box wide frequency domain matrix model of inverter for harmonic degradation mechanism analysis and its solution method[J]. Automation of Electric Power Systems, 2020, 44(18): 155-163. [10] 谢少军, 季林, 许津铭. 并网逆变器电网阻抗检测技术综述[J]. 电网技术, 2015, 39(2): 320-326. Xie Shaojun, Ji Lin, Xu Jinming.Review of grid impedance estimation for gird-connected inverter[J]. Power System Technology, 2015, 39(2): 320-326. [11] Ciobotaru M, Agelidis V, Teodorescu R.Line impedance estimation using model based identification technique[C]//Proceedings of the 2011-14th European Conference on Power Electronics and Applications, Birmingham, 2011: 1-9. [12] Gu Herong, Guo Xiaoqiang, Wang Deyu, et al.Real-time grid impedance estimation technique for grid-connected power converters[C]//2012 IEEE International Symposium on Industrial Electronics, Hangzhou, China, 2012: 1621-1626. [13] Hoffmann N, Fuchs F W.Minimal invasive equivalent grid impedance estimation in inductive-resistive power networks using extended Kalman filter[J]. IEEE Transactions on Power Electronics, 2014, 29(2): 631-641. [14] 王迎晨, 杨少兵, 宋可荐, 等. 基于谐波耦合机理的V/v接线牵引供电系统谐波阻抗辨识方法[J]. 中国电机工程学报, 2021, 41(11): 3818-3828. Wang Yingchen, Yang Shaobing, Song Kejian, et al.Harmonic impedance identification method of V/v connection traction power supply system based on harmonic coupling mechanism[J]. Proceedings of the CSEE, 2021, 41(11): 3818-3828. [15] 岳小龙, 卓放, 张政华, 等. 电力电子系统阻抗测量的分段二叉树法[J]. 电工技术学报, 2015, 30(24): 76-83. Yue Xiaolong, Zhuo Fang, Zhang Zhenghua, et al.Segmented binary tree method for power electronic system impedance measurement[J]. Transactions of China Electrotechnical Society, 2015, 30(24): 76-83. [16] 师洪涛, 卓放, 杨祯, 等. 基于改进正弦调制电流注入的三相交流电源系统谐波阻抗测量研究[J]. 电工技术学报, 2015, 30(8): 257-264. Shi Hongtao, Zhuo Fang, Yang Zhen, et al.Study of harmonic impedance measurement for three-phase AC power system based on an improved modulated current injection method[J]. Transactions of China Electrotechnical Society, 2015, 30(8): 257-264. [17] Jordan M, Langkowski H, Do Thanh T, et al.Frequency dependent grid-impedance determination with pulse-width-modulation-signals[C]//2011 7th International Conference-Workshop Compatibility and Power Electronics (CPE), Tallinn, Estonia, 2011: 131-136. [18] 岳小龙, 卓放. 基于叠加法和正弦幅度调制的阻抗测量注入扰动电流信号形式[J]. 电源学报, 2014, 12(3): 8-13, 32. Yue Xiaolong, Zhuo Fang.Injected current perturbation signal form for impedance measurement based on superposition method and sinusoidal amplitude modulation[J]. Journal of Power Supply, 2014, 12(3): 8-13, 32. [19] Martin D, Santi E, Barkley A.Wide bandwidth system identification of AC system impedances by applying pertubations to an existing converter[C]//2011 IEEE Energy Conversion Congress and Exposition, Phoenix, AZ, USA, 2011: 2549-2556. [20] Roinila T, Vilkko M, Sun Jian.Broadband methods for online grid impedance measurement[C]//2013 IEEE Energy Conversion Congress and Exposition, Denver, CO, USA, 2013: 3003-3010. [21] Roinila T, Vilkko M, Sun Jian.Online grid impedance measurement using discrete-interval binary sequence injection[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2014, 2(4): 985-993. [22] Roinila T, Messo T.Online grid-impedance measurement using ternary-sequence injection[J]. IEEE Transactions on Industry Applications, 2018, 54(5): 5097-5103. [23] 潘鹏宇, 宋依桐, 何正友. 可控测量频带的牵引供电系统频域阻抗测量方法[J]. 中国电机工程学报, 2019, 39(18): 5399-5405. Pan Pengyu, Song Yitong, He Zhengyou.Impedance measurement for traction power system at the controlled frequency band[J]. Proceedings of the CSEE, 2019, 39(18): 5399-5405. [24] Pan Pengyu, Hu Haitao, He Zhengyou, et al.Rapid impedance measurement approach based on wideband excitation for single-phase four-quadrant converter of high-speed train[J]. IEEE Transactions on Instrumentation and Measurement, 2021, 70: 1-11. [25] Wu Mingli, Li Jing, Liu Qiujiang, et al.Measurement of impedance-frequency property of traction network using cascaded H-bridge converters: device design and on-site test[J]. IEEE Transactions on Energy Conversion, 2020, 35(2): 746-756. [26] Pan Pengyu, Hu Haitao, Xiao Donghua, et al.An improved controlled-frequency-band impedance measurement scheme for railway traction power system[J]. IEEE Transactions on Industrial Electronics, 2021, 68(3): 2184-2195. [27] Jaksic M, Shen Zhiyu, Cvetkovic I, et al.Wide-bandwidth Identification of small-signal dq impedances of ac power systems via single-phase series voltage injection[C]//2015 17th European Conference on Power Electronics and Applications (EPE'15 ECCE-Europe), Geneva, Switzerland, 2015: 1-10. [28] 宋文胜, 蒋蔚, 刘碧, 等. 单相级联H桥整流器简化模型预测电流控制[J]. 中国电机工程学报, 2019, 39(4): 1127-1138. Song Wensheng, Jiang Wei, Liu Bi, et al.Single-phase cascaded H-bridge rectifiers simplified model predictive current control[J]. Proceedings of the CSEE, 2019, 39(4): 1127-1138. [29] 李冬辉, 孔祥洁, 刘玲玲. 单相双Buck逆变器的无差拍快速重复控制[J]. 电网技术, 2019, 43(10): 3671-3677. Li Donghui, Kong Xiangjie, Liu Lingling.Deadbeat and fast repetitive control for single-phase dual-Buck inverter[J]. Power System Technology, 2019, 43(10): 3671-3677. [30] 毛惠丰, 孔德鹏, 陈增禄, 等. 一种单相H桥电压型逆变器三电平滞环电流跟踪控制方法[J]. 中国电机工程学报, 2015, 35(15): 3904-3911. Mao Huifeng, Kong Depeng, Chen Zenglu, et al.A new three-level hysteresis current controlled single-phase H-bridge voltage source inverters[J]. Proceedings of the CSEE, 2015, 35(15): 3904-3911. [31] 姚楠. 电气化铁道牵引网基波与谐波模型研究[D]. 北京: 北京交通大学, 2008. Yao Nan.A study of fundamental and harmonic frequency modeling for traction network of electric railways[D]. Beijing: Beijing Jiaotong University, 2008.
2024, Vol. 39 
