基于暂态电流相关系数的混合多端高压直流输电线路保护

doi:10.12204/j.issn.1000-7229.2021.05.012

摘要/Abstract

摘要：

混合多端高压直流输电系统结合了传统高压直流输电与柔性直流输电技术的优势,在降低经济成本的同时可实现大容量功率输送、故障穿越与抑制换相失败等功能,是未来电网发展的重要趋势之一。但是混合多端直流输电系统拓扑相对复杂,且全控型电力电子设备耐过流能力较弱,即故障后需保护装置快速可靠地识别故障区间。因此,提出一种基于暂态电流故障分量相关系数的混合多端高压直流输电线路保护策略,只须测量T接汇流母线3个端口各自的暂态电流故障分量并计算相关系数即可准确识别故障区间。仿真结果表明,所提保护方案无需通信,保护装置能在1 ms内动作,能耐受300 Ω过渡电阻与20 dB白噪声的干扰,可较好地满足混合多端高压直流输电系统的保护需求。

关键词: 混合多端高压直流输电, 故障特性, 相关系数, 线路保护

Abstract:

The hybrid multi-terminal HVDC transmission system combines the advantages of conventional HVDC and flexible HVDC transmission technology, which can realize the functions of high-capacity power transmission, fault ride-through and suppression of commutation failure while reducing the economic cost. However, the hybrid multi-terminal system topology is relatively complex, and the fully controlled power electronic equipment has a low ability of enduring over current. Therefore, a kind of line protection strategy based on transient current correlation coefficient for hybrid multi-terminal HVDC transmission is proposed. Current in the three ports of T-type tandem busbar is measured to calculate correlation coefficient, which can accurately identify the fault range. The simulation results show that the proposed protection scheme does not require communication, and the protection can be triggered within 1 ms. Meanwhile, it can withstand the interference of 300 Ω transition resistance and 20 dB white noise. Therefore, the proposed method can better meet the protection requirements of the hybrid multi-terminal HVDC transmission system.

Key words: hybrid multi-terminal HVDC transmission, fault characteristics, correlation, line protection

中图分类号:

TM773

张怿宁, 陈可傲, 罗易萍, 梁晨光, 宁家兴, 聂铭. 基于暂态电流相关系数的混合多端高压直流输电线路保护[J]. 电力建设, 2021, 42(5): 113-121.

ZHANG Yining, CHEN Keao, LUO Yiping, LIANG Chenguang, NING Jiaxing, NIE Ming. Hybrid Multi-Terminal HVDC Transmission Line Protection Based on Transient Current Correlation Coefficient[J]. ELECTRIC POWER CONSTRUCTION, 2021, 42(5): 113-121.

图/表 13

图1 并联型混合多端直流输电系统拓扑

Fig.1 Topology of parallel hybrid multi-terminal HVDC transmission project

图2 直流故障初始阶段换流器故障回路

Fig.2 Converter fault loop at the initial stage of DC fault

图3 直流线路故障的等效电路

Fig.3 Equivalent circuit of a DC line fault

图4 相关系数示意图

Fig.4 Schematic diagram of correlation coefficient

图5 保护基本流程框图

Fig.5 Basic flowchart of protection scheme

表1 混合多端直流输电系统主要参数

Table 1 Main parameters of the hybrid multi-terminal HVDC system

图6 线路L1发生单极接地短路故障

Fig.6 Single pole-to-ground fault occurs on L1

图7 线路L2发生单极接地短路故障

Fig.7 Single pole-to-ground fault occurs on L2

图8 T接汇流母线发生单极接地短路故障

Fig.8 Single pole-to-ground fault occurs on T bus

表2 不同过渡电阻下的保护有效性

Table 2 Protection effectiveness under different transition resistance

图9 不同区间故障下的电流暂态分量与相关系数(过渡电阻为300 Ω)

Fig.9 Transient current component and correlation coefficients in different section with 300 Ω transition resistance

图10 不同区间故障下的电流暂态分量与相关系数(20 dB白噪声)

Fig.10 Transient current component and correlation coefficients in different section with 20 dB white noise

图11 T接汇流母线发生单极接地短路故障(文献[20])

Fig.11 Single pole-to-ground fault occurs on T bus (reference[20])

参考文献 20

[1]	赵畹君. 高压直流输电工程技术[M]. 北京: 中国电力出版社, 2004.
[2]	汤广福. 基于电压源换流器的高压直流输电技术[M]. 北京: 中国电力出版社, 2010.
[3]	KHAN W A, BI T S, JIA K. A review of single phase adaptive auto-reclosing schemes for EHV transmission lines[J]. Protection and Control of Modern Power Systems, 2019,4(1):1-10. doi: 10.1186/s41601-019-0115-7 URL
[4]	HE J H, CHEN K A, LI M, et al. Review of protection and fault handling for a flexible DC grid[J]. Protection and Control of Modern Power Systems, 2020,5(1):1-15. doi: 10.1186/s41601-019-0145-1 URL
[5]	饶宏, 洪潮, 周保荣, 等. 乌东德特高压多端直流工程受端采用柔性直流对多直流集中馈入问题的改善作用研究[J]. 南方电网技术, 2017,11(3):1-5.
	RAO Hong, HONG Chao, ZHOU Baorong, et al. Study on improvement of VSC-HVDC at inverter side of Wudongde multi-terminal UHVDC for the problem of centralized multi-infeed HVDC[J]. Southern Power System Technology, 2017,11(3):1-5.
[6]	SONG G B, HOU J J, GUO B, et al. Pilot protection of hybrid MMC DC grid based on active detection[J]. Protection and Control of Modern Power Systems, 2020,5(1):1-15. doi: 10.1186/s41601-019-0145-1 URL
[7]	YAO Z Q, ZHANG Q, CHEN P, et al. Research on fault diagnosis for MMC-HVDC Systems[J]. Protection and Control of Modern Power Systems, 2016,1(1):1-7. doi: 10.1186/s41601-016-0016-y URL
[8]	LI B, HE J W, LI Y, et al. A review of the protection for the multi-terminal VSC-HVDC grid[J]. Protection and Control of Modern Power Systems, 2019,4(1):1-11. doi: 10.1186/s41601-019-0115-7 URL
[9]	王永平, 赵文强, 杨建明, 等. 混合直流输电技术及发展分析[J]. 电力系统自动化, 2017,41(7):156-167.
	WANG Yongping, ZHAO Wenqiang, YANG Jianming, et al. Hybrid high-voltage direct current transmission technology and its development analysis[J]. Automation of Electric Power Systems, 2017,41(7):156-167.
[10]	索之闻, 陈启超, 李晖, 等. 混合直流输电系统送端交流暂态电压特性研究[J]. 电力系统保护与控制, 2019,47(17):125-132.
	SUO Zhiwen, CHEN Qichao, LI Hui, et al. Research on sending end AC transient voltage characteristics of hybrid HVDC transmission system[J]. Power System Protection and Control, 2019,47(17):125-132.
[11]	董朝阳, 吉攀攀, 冯敏, 等. 基于LCC-FHMMC混合直流输电的控制策略研究及试验验证[J]. 电力系统保护与控制, 2019,47(13):148-155.
	DONG Chaoyang, JI Panpan, FENG Min, et al. Control strategies and experimental verification for hybrid HVDC system based on LCC and FHMMC[J]. Power System Protection and Control, 2019,47(13):148-155.
[12]	王磊, 李兴源, 李宽, 等. 伪双极LCC-VSC型混合高压直流输电系统向无源网络供电的研究[J]. 电力系统保护与控制, 2015,43(21):27-33. doi: 10.7667/j.issn.1674-3415.2015.21.005 URL
	WANG Lei, LI Xingyuan, LI Kuan, et al. Research of pseudo bipolar LCC-VSC hybrid HVDC system supplying passive network[J]. Power System Protection and Control, 2015,43(21):27-33. doi: 10.7667/j.issn.1674-3415.2015.21.005 URL
[13]	蔡宜君, 文明浩, 陈玉, 等. LCC-MMC混合直流输电系统整流侧故障穿越控制策略[J]. 电力系统保护与控制, 2018,46(14):1-8.
	CAI Yijun, WEN Minghao, CHEN Yu, et al. Control strategy of LCC-MMC hybrid HVDC system under rectifier side fault[J]. Power System Protection and Control, 2018,46(14):1-8.
[14]	刘路路, 胡四全, 韩坤, 等. 混合型MMC系统直流故障穿越性能研究[J]. 电力电子技术, 2020,54(2):106-108.
	LIU Lulu, HU Siquan, HAN Kun, et al. Research on DC fault ride through performance of hybrid MMC system[J]. Power Electronics, 2020,54(2):106-108.
[15]	张文嘉, 王荃荃, 李海坤, 等. 基于对称双极接线的全桥型MMC-HVDC直流侧短路故障穿越控制方法[J]. 电力系统保护与控制, 2020,48(16):147-154.
	ZHANG Wenjia, WANG Quanquan, LI Haikun, et al. DC short circuit fault ride-through method based on symmetrical bipolar FBSM-MMC HVDC system[J]. Power System Protection and Control, 2020,48(16):147-154.
[16]	陈争光, 周泽昕, 王兴国, 等. 混合多端直流输电系统线路保护方案研究[J]. 电网技术, 2019,43(7):2617-2622.
	CHEN Zhengguang, ZHOU Zexin, WANG Xingguo, et al. Research on protection scheme of hybrid multi-terminal DC transmission lines[J]. Power System Technology, 2019,43(7):2617-2622.
[17]	洪潮, 时伯年, 孙刚, 等. 基于LCC-MMC的三端混合直流输电系统故障特性与控制保护策略[J]. 电力建设, 2017,38(8):73-79.
	HONG Chao, SHI Bonian, SUN Gang, et al. Fault characteristics and control & protection strategy of three-terminal LCC-MMC hybrid HVDC transmission system[J]. Electric Power Construction, 2017,38(8):73-79.
[18]	李海锋, 张坤, 王钢, 等. 并联型多端混合高压直流线路故障区域判别方法[J]. 电力系统自动化, 2019,43(4):119-125,179.
	LI Haifeng, ZHANG Kun, WANG Gang, et al. Fault area discrimination method for parallel multi-terminal hybrid HVDC line[J]. Automation of Electric Power Systems, 2019,43(4):119-125,179.
[19]	高淑萍, 朱航舰, 叶换飞, 等. 基于纵向阻抗的混合双极直流输电线路保护新原理[J]. 科学技术与工程, 2019,19(14):193-200.
	GAO Shuping, ZHU Hangjian, YE Huanfei, et al. New principle of hybrid bipolar DC transmission line protection based on longitudinal impedance[J]. Science Technology and Engineering, 2019,19(14):193-200.
[20]	ZHANG C, GAO S P, SONG G B, et al. A pilot protection on hybrid DC line based on correlation coefficient[C]// 2019 IEEE Sustainable Power and Energy Conference (iSPEC). Beijing, China: IEEE, 2019: 2575-2579.