Abstract：When there is a severe ground fault in AC grid,the modular multilevel converter high voltage direct current (MMC-HVDC) system connected to passive networks will collapse due to the continuous decline of the DC voltage caused by the imbalanced power transfer.Firstly,the discharging mechanism of the capacitors in the MMC is analyzed.Then an AC fault ride-through strategy of the MMC-HVDC system connected to passive networks is proposed,the key of which is to make a balance between the DC power flowing into and out of the MMC-HVDC system through reducing the power absorbed by the passive networks during the fault.Finally,an MMC-HVDC system connected to passive networks,including induction motors and static load models,is established in the PSCAD/EMTDC software,based on which the discharging mechanism of capacitors in the MMC under the condition of ground fault in AC grid is verified.The simulation results demonstrate that,with the help of the proposed fault ride-through strategy,the drop of the DC voltage is mitigated and the MMC-HVDC system operates steadily during the ground fault in the AC system.
肖亮, 徐政, 刘昇, 安婷, 孔明. 向无源网络供电的MMC-HVDC送端交流故障穿越策略[J]. 电工技术学报, 2016, 31(15): 89-98.
Xiao Liang, Xu Zheng, Liu Sheng, An Ting, Kong Ming. AC Fault Ride-Through Strategy of MMC-HVDC Connected to Passive Networks. Transactions of China Electrotechnical Society, 2016, 31(15): 89-98.
[1] Perez M A,Bernet S,Rodriguez J,et al.Circuit topologies,modelling,control schemes and applications of modular multilevel converters[J].IEEE Transactions on Power Electronics,2015,30(1):4-17. [2] 徐政,屠卿瑞,管敏渊,等.柔性直流输电系统[M].北京:机械工业出版社,2012:1-45. [3] 黄晟,王辉,廖武,等.基于VSC-HVDC串并联拓扑结构风电场协调控制策略研究[J].电工技术学报,2015,30(23):155-162. Huang Sheng,Wang Hui,Liao Wu,et al.The coordinated control strategy based on VSC-HVDC series-parallel topology in wind farm[J].Transactions of China Electrotechnical Society,2015,30(23):155-162. [4] 黄晟,王辉,廖武,等.基于VSC-HVDC海上串联拓扑风电场低电压穿越控制策略研究[J].电工技术学报,2015,30(14):362-369. Huang Sheng,Wang Hui,Liao Wu,et al.Control strategy based on VSC-HVDC series topology offshore wind farm for low voltage ride through[J].Transactions of China Electrotechnical Society,2015,30(14):362-369. [5] 李响,韩民晓,许东.直流串并联海上风电机组控制策略[J].电力系统保护与控制,2015,43(3):46-52. Li Xiang,Han Minxiao,Xu Dong.Control strategy of DC parallel-series offshore wind turbines[J].Power System Protection and Control,2015,43(3):46-52. [6] Francos P L,Verdugo S S,álvarez H F,et al.INELFE-Europe’s first integrated onshore HVDC interconnection[C]//2012 IEEE Power and Energy Society General Meeting,San Diego,CA,2012:1-8. [7] 边晓燕,王本利,陈建平,等.改进的DFIG与VSC-HVDC协调控制改善风电场低电压穿越能力[J].电力系统保护与控制,2016,44(1):9-16. Bian Xiaoyan,Wang Benli,Chen Jianping,et al.Improvement of low voltage ride through capability of wind farm using coordinated control of the improved DFIG and VSC-HVDC[J].Power System Protection and Control,2016,44(1):9-16. [8] 章心因,胡敏强,吴在军,等.基于VSC-HVDC并网风电场的低电压穿越技术研究[J].电力系统保护与控制,2014,42(19):93-99. Zhang Xinyin,Hu Minqiang,Wu Zaijun,et al.Research on the low voltage ride-through technology of integrated wind farms based on VSC-HVDC[J].Power System Protection and Control,2014,42(19):93-99. [9] 张静,徐政,潘武略.VSC-HVDC 系统新型广义直流电压控制策略[J].电力系统自动化,2008,32(21):46-50. Zhang Jing,Xu Zheng,Pan Wulüe.A novel generalized DC voltage control strategy for VSC-HVDC[J].Automation of Electric Power Systems,2008,32(21):46-50. [10]陈海荣.交流系统故障时VSC-HVDC系统的控制与保护策略研究[D].杭州:浙江大学,2007. [11]任敬国,赵建国,于大洋,等.VSC-HVDC输电系统模式切换控制策略[J].电力系统自动化,2012,36(6):69-73. Ren Jingguo,Zhao Jianguo,Yu Dayang,et al.Mode switching control strategy for VSC-HVDC transmission system[J].Automation of Electric Power Systems,2012,36(6):69-73. [12]张静,徐政,王峰.包含 VDCCOL的VSC-HVDC 改进控制策略[J].电力系统自动化,2008,32(22):41-46. Zhang Jing,Xu Zheng,Wang Feng.An improved control strategy for VSC-HVDC using VDCCOL[J].Automation of Electric Power Systems,2008,32(22):41-46. [13]任敬国,李可军,牛林,等.基于附加信号的VSC-HVDC 系统改进有功功率控制策略[J].电力自动化设备,2013,33(7):46-51. Ren Jingguo,Li Kejun,Niu Lin,et al.Advanced active power control strategy based on additional Signal for VSC-HVDC transmission system[J].Electric Power Automation Equipment,2013,33(7):46-51. [14]Hagiwara M,Akagi H.An approach to regulating the DC-link voltage of a voltage-source BTB system during power line faults[J].IEEE Transactions on Industry Applications,2005,41(5):1263-1271. [15]Adam G P,Ahmed K H,Finney S J,et al.AC fault ride-through capability of a VSC-HVDC transmission systems[C]//Proceedings of energy conversion congress and exposition (ECCE),Atlanta,US.2010:12-16. [16]赵成勇,马国鹏,李广凯.向无源网络供电的VSC-HVDC调节特性研究[J].华北电力大学学报,2008,35(6):39-43. Zhao Chengyong,Ma Guopeng,Li Guangkai.Research on characteristics of regulation of VSC-HVDC supplying power to passive network[J].Journal of North China Electric Power University,2008,35(6):39-43. [17]管敏渊,徐政.MMC型柔性直流输电系统无源网络供电的直接电压控制[J].电力自动化设备,2012,32(12):1-5. Guan Minyuan,Xu Zheng.Direct voltage control of MMC-based VSC-HVDC system for passive networks[J].Electric Power Automation Equipment,2012,32(12):1-5. [18]郭春义,赵成勇,王晶.新型双馈入直流输电系统供电无源网络的运行特性研究[J].电工技术学报,2012,27(11):211-218. Guo Chunyi,Zhao Chengyong,Wang Jing.Operation characteristic research on novel double-infeed HVDC system supplying passive network[J].Transactions of China Electrotechnical Society,2012,27(11):211-218. [19]王卫安,桂卫华,马雅青,等.向无源网络供电的模块化多电平换流器型高压直流输电系统控制器设计[J].高电压技术,2012,38(3):751-761. Wang Wei’an,Gui Weihua,Ma Yaqing,et al.Control design for MMC-HVDC system connected to passive network[J].High Votlage Engineering,2012,38(3):751-761. [20]梁营玉,张涛,刘建政,等.向无源网络供电的VSC-HVDC模型预测控制[J].电工技术学报,2015,30(11):78-89. Liang Yingyu,Zhang Tao,Liu Jianzheng,et al.Model predictive control for VSC-HVDC supplying passive networks[J].Transactions of China Electrotechnical Society,2015,30(11):78-89. [21]Zhang L,Harnefors L,Nee H P.Modeling and control of VSC-HVDC links connected to island systems[J].IEEE Transactions on Power Systems,2011,26(2):783-793. [22]管敏渊,徐政.向无源网络供电的MMC型直流输电系统建模与控制[J].电工技术学报,2013,28(2):255-263. Guan Minyuan,Xu Zheng.Modeling and control of modular multilevel converter based VSC-HVDC system connected to passive networks[J].Transactions of China Electrotechnical Society,2013,28(2):255-263. [23]王珂,骆健,杨胜春,等.向无源网络供电的 VSC-HVDC 启动控制研究[J].中国电机工程学报,2011,31(1):277-281. Wang Ke,Luo Jian,Yang Shengchun,et al.Startu Pprocedures for the VSC-HVDC system supplying power to passive network[J].Proceedings of the CSEE,2011,31(1):277-281. [24]Du C,Bollen M H J,Agneholm E,et al.A new control strategy of a VSC-HVDC system for high-quality supply of industrial plants[J].IEEE Transactions on Power Delivery,2007,22(4):2386-2394. [25]蔡新红,赵成勇,庞辉,等.向无源网络供电的MMC-HVDC系统控制与保护策略[J].中国电机工程学报,2014,34(3):405-414. Cai Xinhong,Zhao Chengyong,Pang Hui,et al.Control and protection strategies for MMC-HVDC supplying passive networks[J].Proceedings of the CSEE,2014,34(3):405-414. [26]Price W W,Taylor C W,Rogers G J.Standard load models for power flow and dynamic performance simulation[J].IEEE Transactions on Power Systems,1995,10(3):1302-1313. [27]Liu Shen,Xu Zheng,Hua Wen,et al.Electromechanical transient modeling of modular multilevel converter based multi-terminal HVDC systems[J].IEEE Transactions on Power Systems,2014,29(1):72-83. [28]Shi Xiaojie,Wang Zhiqiang,Liu Bo,et al.Characteristic investigation and control of a modular multilevel converter-based HVDC system under single-line-to-ground fault conditions[J].IEEE Transactions on Power Electronics,2015,30(1):408-421. [29]Guan Minyuan,Xu Zheng.Modeling and control of a modular multilevel converter-based HVDC system under unbalanced grid conditions[J].IEEE Transactions on Power Electronics,2012,27(12):4858-4867. [30]Von Jouanne A,Enjeti P N,Banerjee B.Assessment of ride-through alternatives for adjustable-speed drives[J].IEEE Transactions on Industry Applications,1999,35(4):908-916. [31]Das J C.Effects of momentary voltage dips on the operation of induction and synchronous motors[J].IEEE Transactions on Industry Applications,1990,26(4):711-718. [32]Bollen M H J,Zhang L D.Analysis of voltage tolerance of AC adjustable-speed drives for three-phase balanced and unbalanced sags[J].IEEE Transactions on Industry Applications,2000,36(3):904-910.
2016, Vol. 31 
