Full-Half Bridge Hybrid VSC-HVDC Transmission Line Protection Method Based on Power Characteristics of Bridge Arms
Lei Shunguang1, Shu Hongchun2, Li Zhimin1
1. School of Electrical Engineering and Automation Harbin Institute of Technology Harbin 150001 China; 2. Faculty of Electric Power Engineering Kunming University of Science and Technology Kunming 650051 China
Abstract:The "Carbon-Neutral" goal is the main driving force to build a new power system with renewable energy. Due to the advantages of low loss and no commutation failure, the voltage source converter (VSC) transmission based on modular multilevel converter (MMC) has been widely used in large-scale renewable energy grid-connected power transmission. When the DC line faults, the fault current increase rapidly, causing irreversible damage to power electronic power devices and even paralysis of the transmission system. It brings a serious crisis to the safe operation of the power grid. Therefore, fast and selective identification of DC line faults is one of the key technologies to be solved urgently. The protection research of the VSC-HVDC transmission system based on full-half hybrid sub-modular structure is of great significance to the large capacity transmission of renewable energy. Firstly, the bridge arm power calculation circuit is equivalent when the DC line is faulted, and the change characteristics of the bridge arm power under the DC line fault are analyzed. When the DC line faults, the bridge arm power increases. Then, the bridge arm power under DC fault is numerically analyzed, and the causes of errors are analyzed in detail. Finally, based on the power characteristics of the bridge arm, the protection scheme of the DC transmission line is proposed, the set-up element, the identification element of internal and external fault, and the faulty poles detection element are constructed, and the complete protection flow chart is given. A double-ended true bipolar full-half hybrid MMC-HVDC transmission system is built on the RTDS platform. The system adopts the overhead line, the transmission distance is 500 km, and the transmission line adopts the frequency-variable model, and the transmission capacity is 1 280 MW, the fault occurrence time is 3 s, the simulation step is 2 μs, the sampling step is 100 μs, the sampling frequency is 10 kHz, and the protection interruption time is 0.7 ms. Firstly, the protection effect under different fault types is verified. When an AC fault occurs, $\delta 0$, it is judged as an external fault. When a DC fault occurs, $\delta 0$, it is judged as an internal fault. When a positive fault occurs, $S\ge 0.9$, when a negative fault occurs, $S\le 1.1$. When a pole-to-pole fault occurs, $0.9S1.1$, which satisfies the pole detection criterion. The protection method proposed in this paper can correctly identify the fault and select the faulty poles under different fault types. Then the protection effect under different transition resistances and distance is verified. When the transition resistances are 0.01 Ω, 100 Ω, 300 Ω and 500 Ω, the fault distance are 20 km, 120 km, 300 km and 480 km, respectively. When a positive fault, a negative fault, and a pole-to-pole fault occurs, the internal/external fault identification criteria and pole selection criterion is satisfied. Furthermore, the anti-interference ability of the protection scheme is verified. And compared with the existing protection methods, the protection scheme has strong ability to response to the high transition resistance and noise interference. Based on the energy point, this paper analyzes the bridge arm power characteristics of the VSC -HVDC transmission system under DC line faults, proposes a protection scheme of this VSC -HVDC transmission system based on the bridge arm power characteristics. The conclusion can be drawn as follows: (1) When a DC line faults, the bridge arm capacitor discharges to the fault point on the DC side, and the fault current direction is the same as the current direction of the original system. Therefore, when the DC line faults, the bridge arm power increases. (2) The protection scheme is constructed by using the bridge arm power characteristics. The scheme is simple, and it can reliably identify the DC line fault. (3) Compared with the traditional time domain and frequency domain method, it is verified that the protection scheme proposed is highly reliable, selective, and sensitive, has strong ability to response to the high transition resistance and noise interference.
雷顺广, 束洪春, 李志民. 基于桥臂功率特征的全-半混合型柔性直流输电线路保护[J]. 电工技术学报, 2023, 38(13): 3563-3575.
Lei Shunguang, Shu Hongchun, Li Zhimin. Full-Half Bridge Hybrid VSC-HVDC Transmission Line Protection Method Based on Power Characteristics of Bridge Arms. Transactions of China Electrotechnical Society, 2023, 38(13): 3563-3575.
[1] 陈皓勇. “双碳”目标下的电能价值分析与市场机制设计[J]. 发电技术, 2021, 42(2): 141-150. Chen Haoyong.Electricity value analysis and market mechanism design under carbon-neutral goal[J]. Power Generation Technology, 2021, 42(2): 141-150. [2] 束洪春, 代月, 安娜, 等. 基于交叉重叠差分变换的MMC-HVDC线路故障识别方法[J]. 电工技术学报, 2021, 36(1): 203-214, 226. Shu Hongchun, Dai Yue, An Na, et al.Fault identification method of MMC-HVDC line based on sequential overlapping derivative transform[J]. Transactions of China Electrotechnical Society, 2021, 36(1): 203-214, 226. [3] 汤广福, 贺之渊, 庞辉. 柔性直流输电工程技术研究、应用及发展[J]. 电力系统自动化, 2013, 37(15): 3-14. Tang Guangfu, He Zhiyuan, Pang Hui.Research, application and development of VSC-HVDC engineering technology[J]. Automation of Electric Power Systems, 2013, 37(15): 3-14. [4] 周家培, 赵成勇, 李承昱, 等. 基于直流电抗器电压的多端柔性直流电网边界保护方案[J]. 电力系统自动化, 2017, 41(19): 89-94, 146. Zhou Jiapei, Zhao Chengyong, Li Chengyu, et al.Boundary protection scheme for multi-terminal flexible DC grid based on voltage of DC reactor[J]. Automation of Electric Power Systems, 2017, 41(19): 89-94, 146. [5] 安娜, 束洪春, 郭瑜, 等. 基于感性模糊识别的MMC直流输电线路单极接地故障分析[J]. 电力自动化设备, 2021, 41(3): 71-77. An Na, Shu Hongchun, Guo Yu, et al.Single pole-to-ground fault analysis of MMC DC transmission lines based on inductance fuzzy identification[J]. Electric Power Automation Equipment, 2021, 41(3): 71-77. [6] 陈继开, 孙川, 李国庆, 等. 双极MMC-HVDC系统直流故障特性研究[J]. 电工技术学报, 2017, 32(10): 53-60, 68. Chen Jikai, Sun Chuan, Li Guoqing, et al.Study on characteristics of DC fault in bipolar MMC-HVDC system[J]. Transactions of China Electrotechnical Society, 2017, 32(10): 53-60, 68. [7] 陈剑, 杜文娟, 王海风. 基于对抗式迁移学习的含柔性高压直流输电的风电系统次同步振荡源定位[J]. 电工技术学报, 2021, 36(22): 4703-4715. Chen Jian, Du Wenjuan, Wang Haifeng.Location method of subsynchronous oscillation source in wind power system with VSC-HVDC based on adversarial transfer learning[J]. Transactions of China Electrotechnical Society, 2021, 36(22): 4703-4715. [8] 姚良忠, 吴婧, 王志冰, 等. 未来高压直流电网发展形态分析[J]. 中国电机工程学报, 2014, 34(34): 6007-6020. Yao Liangzhong, Wu Jing, Wang Zhibing, et al.Pattern analysis of future HVDC grid development[J]. Proceedings of the CSEE, 2014, 34(34): 6007-6020. [9] Tang Guangfu, He Zhiyuan, Pang Hui, et al.Basic topology and key devices of the five-terminal DC grid[J]. CSEE Journal of Power and Energy Systems, 2015, 1(2): 22-35. [10] Li Bin, He Jiawei, Tian Jie, et al.DC fault analysis for modular multilevel converter-based system[J]. Journal of Modern Power Systems and Clean Energy, 2017, 5(2): 275-282. [11] 付华, 陈浩轩, 李秀菊, 等. 含边界元件的MMC-MTDC直流侧单端量故障辨识方法[J]. 电工技术学报, 2021, 36(1): 215-226. Fu Hua, Chen Haoxuan, Li Xiuju, et al.MMC-MTDC DC side single-ended quantity fault identification method with boundary elements[J]. Transactions of China Electrotechnical Society, 2021, 36(1): 215-226. [12] 魏晓光, 周万迪, 张升, 等. 模块化混合式高压直流断路器研究与应用[J]. 中国电机工程学报, 2020, 40(6): 2038-2046. Wei Xiaoguang, Zhou Wandi, Zhang Sheng, et al.Research and application of modular hybrid high voltage DC circuit breaker[J]. Proceedings of the CSEE, 2020, 40(6): 2038-2046. [13] 熊岩, 饶宏, 许树楷, 等. 特高压多端混合直流输电系统启动与故障穿越研究[J]. 全球能源互联网, 2018, 1(4): 478-486. Xiong Yan, Rao Hong, Xu Shukai, et al.Research on start and fault ride-through strategy for ultra-high voltage multi-terminal hybrid DC transmission system[J]. Journal of Global Energy Interconnection, 2018, 1(4): 478-486. [14] Shu Hongchun, Wang Guangxue, Tian Xincui, et al.Single-ended protection method of MMC-HVDC transmission line based on random matrix theory[J]. International Journal of Electrical Power & Energy Systems, 2022, 142: 108299. [15] 曹润彬, 李岩, 许树楷, 等. 特高压混合多端直流线路保护配置与配合研究[J]. 南方电网技术, 2018, 12(11): 52-58, 83. Cao Runbin, Li Yan, Xu Shukai, et al.Research on configuration and coordination of multi-terminal hybrid UHVDC line protection[J]. Southern Power System Technology, 2018, 12(11): 52-58, 83. [16] Fletcher S D A, Norman P J, Fong K, et al. High-speed differential protection for smart DC distribution systems[J]. IEEE Transactions on Smart Grid, 2014, 5(5): 2610-2617. [17] 宋国兵, 蔡新雷, 高淑萍, 等. VSC-HVDC频变参数电缆线路电流差动保护新原理[J]. 中国电机工程学报, 2011, 31(22): 105-111. Song Guobing, Cai Xinlei, Gao Shuping, et al.Novel Current differential protection principle of VSC-HVDC considering frequency-dependent characteristic of cable line[J]. Proceedings of the CSEE, 2011, 31(22): 105-111. [18] Zheng Xiaodong, Tai Nengling, Thorp J S, et al.Improved differential protection scheme for long distance UHVDC transmission line[C]//2014 IEEE PES General Meeting | Conference & Exposition, National Harbor, MD, USA: 1-5. [19] Sneath J, Rajapakse A D.Fault detection and interruption in an earthed HVDC grid using ROCOV and hybrid DC breakers[J]. IEEE Transactions on Power Delivery, 2016, 31(3): 973-981. [20] 戴志辉, 刘宁宁, 何永兴, 等. 基于直流滤波环节暂态能量比的高压直流线路纵联保护[J]. 电工技术学报, 2020, 35(9): 1985-1998. Dai Zhihui, Liu Ningning, He Yongxing, et al.A pilot protection for HVDC transmission lines based on the ratio of DC filter link transient energy[J]. Transactions of China Electrotechnical Society, 2020, 35(9): 1985-1998. [21] 李爱民, 蔡泽祥, 李晓华. 直流线路行波传播特性的解析[J]. 中国电机工程学报, 2010, 30(25): 94-100. Li Aimin, Cai Zexiang, Li Xiaohua.Study on the propagation characteristics of traveling waves in HVDC transmission lines on the basis of analytical method[J]. Proceedings of the CSEE, 2010, 30(25): 94-100. [22] 甄永赞, 苏宁赛, 杨荆宜. 直流输电线路极波变化率保护的拓展方法研究[J]. 中国电机工程学报, 2021, 41(15): 5212-5220. Zhen Yongzan, Su Ningsai, Yang Jingyi.Research on extension method of polar wave change rate protection for HVDC transmission line[J]. Proceedings of the CSEE, 2021, 41(15): 5212-5220. [23] 郑伟, 武霁阳, 李海锋, 等. 特高压直流线路自适应行波保护[J]. 电网技术, 2015, 39(7): 1995-2001. Zheng Wei, Wu Jiyang, Li Haifeng, et al.Research on adaptive travelling wave based protection for UHVDC transmission line[J]. Power System Technology, 2015, 39(7): 1995-2001. [24] 张冰, 赵书强, 甄永赞. 柔性直流输电的改进行波保护仿真研究[J]. 电力系统保护与控制, 2017, 45(16): 58-63. Zhang Bing, Zhao Shuqiang, Zhen Yongzan.Simulation study of an improved traveling wave protection for VSC-HVDC transmission system[J]. Power System Protection and Control, 2017, 45(16): 58-63. [25] 汤广福, 王高勇, 贺之渊, 等. 张北500 kV直流电网关键技术与设备研究[J]. 高电压技术, 2018, 44(7): 2097-2106. Tang Guangfu, Wang Gaoyong, He Zhiyuan, et al.Research on key technology and equipment for Zhangbei 500 kV DC grid[J]. High Voltage Engineering, 2018, 44(7): 2097-2106. [26] 戴志辉, 刘自强, 杨明玉, 等. 基于暂态行波幅值积分的柔性直流电网纵联保护[J]. 中国电机工程学报, 2020, 40(20): 6578-6592. Dai Zhihui, Liu Ziqiang, Yang Mingyu, et al.Pilot protection for flexible DC grids based on amplitude integral of transient wavelet[J]. Proceedings of the CSEE, 2020, 40(20): 6578-6592. [27] 童宁, 林湘宁, 张雪松, 等. 不依赖于边界元件的架空型多端柔直电网就地测距式接地保护原理[J]. 中国电机工程学报, 2019, 39(7): 2049-2060. Tong Ning, Lin Xiangning, Zhang Xuesong, et al.Fault location based single-ended protection strategy for overhead VSC-MTDC independent on boundary component[J]. Proceedings of the CSEE, 2019, 39(7): 2049-2060. [28] 梁远升, 黄泽杰, 李海锋, 等. 基于行波相位特性的三端混合直流线路行波保护原理[J]. 中国电机工程学报, 2021, 41(13): 4525-4542. Liang Yuansheng, Huang Zejie, Li Haifeng, et al.Phase characteristics based travelling wave protection for transmission line of three-terminal hybrid HVDC system[J]. Proceedings of the CSEE, 2021, 41(13): 4525-4542. [29] 徐雨哲, 徐政, 张哲任, 等. 基于LCC和混合型MMC的混合直流输电系统控制策略[J]. 广东电力, 2018, 31(9): 13-25. Xu Yuzhe, Xu Zheng, Zhang Zheren, et al.Control strategy for hybrid HVDC transmission system based on LCC and hybrid MMC[J]. Guangdong Electric Power, 2018, 31(9): 13-25. [30] 田培涛, 吴庆范, 黄金海, 等. 基于LCC和FHMMC的混合多端直流系统线路保护方案研究[J]. 电力系统保护与控制, 2021, 49(1): 170-177. Tian Peitao, Wu Qingfan, Huang Jinhai, et al.Research on protection strategy of a hybrid multi-terminal DC system based on LCC and FHMMC[J]. Power System Protection and Control, 2021, 49(1): 170-177. [31] 祝新驰, 李海锋, 黄炟超, 等. 基于触发角变化特性的高压直流线路纵联保护[J]. 电力自动化设备, 2020, 40(6): 163-171. Zhu Xinchi, Li Haifeng, Huang Dachao, et al.Pilot protection of HVDC power transmission lines based on variation characteristics of firing angle[J]. Electric Power Automation Equipment, 2020, 40(6): 163-171. [32] 郑伟, 张楠, 杨光源. 西门子及ABB直流线路行波保护对比和改进研究[J]. 电力系统保护与控制, 2015, 43(24): 149-154. Zheng Wei, Zhang Nan, Yang Guangyuan.Comparative and improvement investigation on the DC transmission line traveling wave protections of Siemens and ABB[J]. Power System Protection and Control, 2015, 43(24): 149-154. [33] Zheng Yuping, He Jiawei, Li Bin.et al.Research on DC protection strategy in multi-terminal hybrid HVDC system[J]. Engineering, 2021, 7(8): 65-88. [34] Liu Xiaolei, Osman A H, Malik O P.Hybrid traveling wave/boundary protection for monopolar HVDC line[J]. IEEE Transactions on Power Delivery, 2009, 24(2): 569-578. [35] Li Rui, Xu Lie, Yao Liangzhong.DC fault detection and location in meshed multiterminal HVDC systems based on DC reactor voltage change rate[J]. IEEE Transactions on Power Delivery, 2017, 32(3): 1516-1526.