应用于配电网柔性互联的变换器拓扑
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摘要
大量分布式能源的接入,以及用户负荷的多样化,将使配电网双向潮流、电压越限、馈线负荷不均衡等问题更加突出。利用电力电子技术实现配电网的柔性互联,可在不增加配电系统短路电流的条件下灵活控制潮流,是推动配电网形态结构与运行模式升级的有效方案。该文对应用于配电网柔性互联的变换器拓扑进行了探究。依据接入方式、工作原理、基本结构的差异,将多种柔性互联拓扑进行多层级分类;在充分考虑配电线路特性的基础上,建立了接入各类变换器的配电网等效电路和相量图,深入研究其潮流调节机理,并归纳相应典型拓扑的结构特点与运行方式;对比分析不同配电网柔性互联拓扑的功能性与经济性,给出了多种类型拓扑的适用场景。通过以上工作,为不同配电网应用场景下柔性互联拓扑的选取提供了参考,并指明拓扑在未来的改进方向,以期推动柔性互联方案在装备实现层面的技术进步。
The integration of distributed generation and the diversity of user's load, lead to reverse power flow, voltage rise and feeder imbalance, which will deteriorate the operation of distribution system. Flexible interconnection that takes advantage of power converters between distribution feeders could be a feasible solution, which could control the power flow without increasing short-circuit current. In this paper, the power converter topologies applied in flexible interconnection of distribution system was explored from the perspective of power electronics. The topologies were classified based on the integration type, operation principle and basic structure. The equivalent circuits and phasor diagrams of distribution grid integrated with different power converters were established. The power flow control mechanism of different topologies was studied based on the consideration of the features of distribution feeders. The characteristics of typical topologies were concluded. The functionality and economy of topologies were compared. At last, the suitable application settings of different topologies were analyzed. Researchers can figure out the topology requirements and choose the suitable topology for the specific application environment. Furthermore, the way to improve converter topologies will be indicated, so as to promote the technological development in flexible interconnection scheme.
The integration of distributed generation and the diversity of user's load, lead to reverse power flow, voltage rise and feeder imbalance, which will deteriorate the operation of distribution system. Flexible interconnection that takes advantage of power converters between distribution feeders could be a feasible solution, which could control the power flow without increasing short-circuit current. In this paper, the power converter topologies applied in flexible interconnection of distribution system was explored from the perspective of power electronics. The topologies were classified based on the integration type, operation principle and basic structure. The equivalent circuits and phasor diagrams of distribution grid integrated with different power converters were established. The power flow control mechanism of different topologies was studied based on the consideration of the features of distribution feeders. The characteristics of typical topologies were concluded. The functionality and economy of topologies were compared. At last, the suitable application settings of different topologies were analyzed. Researchers can figure out the topology requirements and choose the suitable topology for the specific application environment. Furthermore, the way to improve converter topologies will be indicated, so as to promote the technological development in flexible interconnection scheme.
引文
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[2]马钊,安婷,尚宇炜.国内外配电前沿技术动态及发展[J].中国电机工程学报,2016,36(6):1552-1567.Ma Zhao,An Ting,Shang Yuwei.State of the art and development trends of power distribution technologies[J].Proceedings of the CSEE,2016,36(6):1552-1567(in Chinese).
[3]Katiraei F,Aguero J.Solar PV integration challenges[J].IEEE Power and Energy Magazine,2011,9(3):62-71.
[4]Bebic J,Walling R,O’Brien K,et al.The sun also rises[J].IEEE Power and Energy Magazine,2009,7(3):45-54.
[5]孟庭如,邹贵彬,许春华,等.一种分区协调控制的有源配电网调压方法[J].中国电机工程学报,2017,,37(10):2852-2860.Meng Tingru,Zou Guibin,Xu Chunhua,et al.A voltage regulation method based on district-dividing coordinated control for active distribution network[J].Proceedings of the CSEE,2017,37(10):2852-2860(in Chinese).
[6]Chaudhary S K,Guerrero J M,Teodorescu R.Enhancing the capacity of the AC distribution system using DCinterlinks:a step toward future DC grid[J].IEEETransactions on Smart Grid,2015,6(4):1722-1729.
[7]王成山,宋关羽,李鹏,等.一种联络开关和智能软开关并存的配电网运行时序优化方法[J].中国电机工程学报,2016,36(9):2315-2321.Wang Chengshan,Song Guanyu,Li Peng,et al.A hybrid optimization method for distribution network operation with SNOP and tie switch[J].Proceedings of the CSEE,2016,36(9):2315-2321(in Chinese).
[8]张沈习,袁加妍,程浩忠,等.主动配电网中考虑需求侧管理和网络重构的分布式电源规划方法[J].中国电机工程学报,2016,36(S1):1-9.Zhang Shenxi,Yuan Jianyan,Cheng Haozhong,et al.Optimal distributed generation planning in active distribution network considering demand side management and network reconfiguration[J].Proceedings of the CSEE,2016,36(S1):1-9(in Chinese).
[9]颜湘武,段聪,吕正,等.基于动态拓扑分析的遗传算法在配电网重构中的应用[J].电网技术,2014,38(6):1639-1643.Yan Xiangwu,Duan Cong,LüZheng,et al.Application of dynamic topological analysis based genetic algorithm in distribution network reconfiguration[J].Power System Technology,2014,38(6):1639-1643(in Chinese).
[10]Stetz T,Marten F,Braun M.Improved low voltage grid-integration of photovoltaic systems in Germany[J].IEEE Transactions on Sustainable Energy,2013,4(2):534-542.
[11]Celli G,Pilo F,Pisano G.Meshed vs.radial MVdistribution network in presence of large amount of DG[C]//Power Systems Conference and Exposition.New York,USA:IEEE,2004:709-714.
[12]王成山,宋关羽,李鹏,等.基于智能软开关的智能配电网柔性互联技术及展望[J].电力系统自动化,2016,40(22):168-175.Wang Chengshan,Song Guanyu,Li Peng,et al.Research and prospect for soft open point based flexible interconnection technology for smart distribution network[J].Automation of Electric Power Systems,2016,40(22):168-175(in Chinese).
[13]王成山,孙充勃,李鹏,等.基于SNOP的配电网运行优化及分析[J].电力系统自动化,2015,39(9):82-87.Wang Chengshan,Sun Chongbo,Li Peng,et al.SNOP-based operation optimization and analysis of distribution networks[J].Automation of Electric Power Systems,2015,39(9):82-87(in Chinese).
[14]Okada N.Autonomous loop power flow control for distribution system[C]//AC-DC Power Transmission.London,UK:IET,2001:150-155.
[15]Okada N,Takasaki M,Sakai H,et al.Development of a 6.6kV~1MVA Transformerless Loop Balance Controller[C]//Power Electronics Specialists Conference.Orlando,USA:IEEE,2007:1087-1091.
[16]Nguyen H,Kling L,Ribeito F.Smart power router:a flexible agent-based converter interface in active distribution networks[J].IEEE Transactions on Smart Grid,2011,2(3):487-495.
[17]Bloemink M,Green C.Increasing distributed generation penetration using soft normally-open points[C]//Power and Energy Society General Meeting.Providence,USA:IEEE,2010:1-8.
[18]王岸.SNOP的研究及其在配电网中的应用[D].北京:北京交通大学,2014.Wang An.Research on SNOP and its application in distribution network[D].Beijing:Beijing Jiaotong University,2014(in Chinese).
[19]孙充勃.含多种直流环节的智能配电网快速仿真与模拟关键技术研究[D].天津:天津大学,2015.Sun Chongbo.Study on key technologies of fast simulation and modeling for smart distribution gird with multi-DC components[D].Tianjin:Tianjin University,2015(in Chinese).
[20]晏阳,廖清芬,刘涤尘,等.基于潮流介数的SNOP配置及主动配电系统优化[J].南方电网技术,2015,9(11):92-98.Yan Yang,Liao Qingfen,Liu Dichen,et al.Power flow betweenness Based SNOP allocation and active distribution network optimization[J].Southern Power System Technology,2015,9(11):92-98(in Chinese).
[21]王成山,宋关羽,李鹏,等.一种联络开关和智能软开关并存的配电网运行时序优化方法[J].中国电机工程学报,2016,36(9):2315-2321.Wang Chengshan,Song Guanyu,Li Peng,et al.A hybrid optimization method for distribution network operation with SNOP and tie switch[J].Proceedings of the CSEE,2016,36(9):2315-2321(in Chinese).
[22]晏阳,廖清芬,胡静竹,等.基于SNOP的主动配电网多时间尺度优化策略[J].电力建设,2016,37(2):125-131.Yan Yang,Liao Qingfen,Hu Jingzhu,et al.Multi-time scale optimization strategy of active distribution network based on SNOP[J].Electric Power Construction,2016,37(2):125-131(in Chinese).
[23]李智诚,吴建中,和敬涵,等.软常开点的双闭环控制及其在配电网中的应用[J].智能电网,2013,1(1):49-55.Li Zhicheng,Wu Jianzhong,He Jinghan,et al.Dual closed-loop control of soft normally open points and its application in distribution networks[J].Smart Grid,2013,1(1):49-55(in Chinese).
[24]吴瑞竹.10kV电网母线的电压及功率潮流控制策略研究[D].成都:西华大学,2014.Wu Ruizhu.research on a control strategy of voltages and power flow on 10k V busbars[D].Chengdu:Xihua University,2014(in Chinese).
[25]仉志华,徐丙垠,陈青.基于统一潮流控制器的配电环网潮流优化控制策略[J].电网技术,2012,36(6):122-126.Zhang Zhihua,Xu Bingyin,Chen Qing.Control strategies for UPFC-based optimal power flow of distribution network with normally closed-loop operation[J].Power System Technology,2012,36(6):122-126(in Chinese).
[26]Yan P,Sekar A.Analysis of radial distribution systems with embedded series FACTS devices using a fast line flow-based algorithm[J].IEEE Transactions on Power Systems,2005,20(4):1775-1782.
[27]Peng F Z.Flexible AC transmission systems(FACTS)and resilient AC distribution systems(RACDS)in smart grid[J].Proceedings of the IEEE,2017,105(99):1-17.
[28]Ren Y.Comprehensive research of applying TCSC to improve the property of distribution network[C]//Power and Energy Engineering Conference.Shanghai,China:IEEE,2012:1-4.
[29]Watanabe E,Souza L,Jesus F,et al.GCSC-gate controlled series capacitor:a new FACTS device for series compensation of transmission lines[C]//Transmission and Distribution Conference and Exposition.Latin America:IEEE,2004:981-986.
[30]Saradarzadeh M,Farhangi S,Schanen J L,et al.Combination of power flow controller and short-circuit limiter in distribution electrical network using a cascaded H-bridge distribution-static synchronous series compensator[J].Generation Transmission&Distribution Iet,2013,6(11):1121-1131.
[31]Pereda J,Green T.Direct modular multilevel converter with six branches for flexible distribution networks[J].IEEE Transactions on Power Delivery,2016,31(4):1728-1737.
[32]张茂松,王群京,李国丽,等.中点钳位式三电平D-STATCOM的鲁棒电流和中点电位控制策略研究[J].中国电机工程学报,2016,36(14):3868-3877.Zhang Maosong,Wang Qunjing,Li Guoli,et al.Study on robust current and neutral-point potential control for the D-STATCOM based on NPC three-level inverter[J].Proceedings of the CSEE,2016,36(14):3868-3877(in Chinese).
[33]单任仲,陈来军,沈沉,等.三相静止坐标下H桥配网静止同步补偿器重复学习控制[J].电网技术,2013,37(3):616-621.Shan Renzhong,Chen Laijun,Shen Chen,et al.Repetitive learning control in three-phase stationary reference frame for H-bridge D-STATCOM[J].Power System Technology,2013,37(3):616-621(in Chinese).
[34]Shahnia F.Application and control of a DSTATCOM to couple neighboring low voltage feeders[C]//Industrial Technology.Taipei,China:IEEE,2016:476-481.
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