Abstract In an active distribution network environment, the intermittent and random renewable generation units, such as small wind generation, photovoltaic(PV), and energy storage unit, e.g. battery, can be combined to form a microgrid (MG). The microgrid can be controlled as a generator or a load with a timed constant power flow by coordinating the power output of its multiple renewable generation units. This way is helpful for the active distribution network to dispatch and manage the microgrid group and to promote the penetration of distributed renewable energy sources. A hierarchical coordination control strategy is employed by considering the change of wind speed and solar radiation intensity as well as the limited storage capacity. A method to calculate the expected interchange power plow of the microgrid tie-lineaccording to predicted wind speed and solar radiation intensity in each time period is presented. A central controller is designed to formulate the plan of microgrid tie-line interchange power plow with the dispatch center of the active distribution network by communicating with upper active distribution grid center. The central controller can also select the correct operation modes and achieve the smooth switch between different operation modes, to select and manage the local controllers. The hierarchical control strategy realizes the seamless transformation of the running state, and ensures the output power flow of the microgrid to follow the demand of the tie-line interchange power. When the difference between the sum of output instantaneous power of wind generation, PV in the microgrid and tie-line interchange power plow is big, the microgrid may partly abandon the generation active power of wind and PV power generation. A simulation model of wind/PV/battery microgrid is established and the simulation results confirm the effectiveness of the proposed control strategy.
[1] 杨新法,苏剑,吕志鹏,等.微电网技术综述[J].中国电机工程学报,2014,34(1):57-70. Yang Xinfa,Su Jian,Lü Zhipeng,et al.Overview on micro-grid technology[J].Proceedings of the CSEE,2014,34(1):57-70. [2] Hatziargyriou N,Asand H,Iravani R,et al.Microgrids[J].IEEE Power and Energy Magazine,2007,5(4):78-94. [3] Olivares D E,Mehrizi-Sani A,Etemadi A H,et al.Trends in microgrid control [J].IEEE Transactions on Smart Grid,2014,5(4):1905-1919. [4] 王成山,武震,李鹏.微电网关键技术研究[J].电工技术学报,2014,29(2):1-12. Wang Chengshan,Wu Zhen,Li Peng.Research on key technologies of microgrid[J].Transactions of China Electrotechnical Society,2014,29(2):1-12. [5] 支娜,张辉,肖曦.提高直流微电网动态特性的改进下垂控制策略研究[J].电工技术学报,2016,31(3):31-39. Zhi Na,Zhang Hui,Xiao Xi.Research on the improved droop control strategy for improvingthe dynamic characteristics of DC microgrid[J].Transactions of China Electrotechnical Society,2016,31(3):31-39. [6] 王逸超,罗安,金国彬.微网逆变器的改进鲁棒下垂多环控制[J].电工技术学报,2015,30(22):116-123. Wang Yichao,Luo An,Jin Guobin.Improved robust droop multiple loop control for parallel inverters in microgrid [J].Transactions of China Electrotechnical Society,2015,30(22):116-123. [7] 刘文,杨慧霞,祝斌.微电网关键技术研究综述[J].电力系统保护与控制,2012,40(14):152-155. Liu Wen,Yang Huixia,Zhu Bin.Survey on key technologies of microgrid[J].Power System Protection and Control,2012,40(14):152-155. [8] Xiao Jianfeng,Wang Peng,Setyawan L.Hierarchical control of hybrid energy storage system in DC microgrids[J].IEEE Transactions on Industrial Electronics,2015,62(8):4915-4924. [9] Guerrero J M,Vasquez J C,Matas J,et al.Hierarchical control of droop-controlled AC and DC microgrids—a general approach toward standardization[J].IEEE Transactions on Industrial Electronics,2011,58(1):158-172. [10]Vandoorn T L,Vasquez J C,De Kooning J,et al.Microgrids:hierarchical control and an overview of the control and reserve management strategies[J].IEEE Industrial Electronics Magazine,2013,7(4):42-55. [11]Kim M,Kwasinski A.Decentralized hierarchical control of active power distribution nodes[J].IEEE Transactions on Energy Conversion,2014,29(4):934-943. [12]Wang Dan,Ge Shaoyun,Jia Hongjie,et al.A demand response and battery storage coordination algorithm for providing microgrid tie-line smoothing services[J].IEEE Transactions on Sustainable Energy,2014,5(2):476-486. [13]刘霞,江全元.风光储混合系统的协调优化控制[J].电力系统自动化,2012,36(14):95-100. Liu Xia,Jiang Quanyuan.An optimal coordination control of hybrid wind/photovoltaic/energy storage system[J].Automation of Electric Power System,2012,36(14):95-100. [14]李碧辉,申洪,汤涌,等.风光储联合发电系统储能容量对有功功率的影响及评价指标[J].电网技术,2011,35(4):196-204. Li Bihui,Shen Hong,Tang Yong,et al.Impacts of energy storage capacity configuration of HPWS to active power characteristics and its relevant indices[J].Power System Technology,2011,35(4):196-204. [15]蔡国伟,孔令国,潘超,等.风光储联合发电系统的建模及并网控制策略[J].电工技术学报,2013,28(9):123-128. Cai Guowei,Kong Lingguo,Pan Chao,et al.System modeling of wind-PV-ES hybrid power system and its controlstrategy for grid-connected[J].Transactions of China Electrotechical Society,2013,28(9):123-128. [16]任洛卿,白泽洋,于昌海,等.风光储联合发电系统有功控制策略研究及工程应用[J].电工技术学报,2013,28(9):105-111. Ren Luoqing,Bai Zeyang,Yu Changhai,et al.Research on active power control strategy for wind/photovoltaic/energy storage hybrid power system and its engineering application[J].Automation of Electric Power System,2013,28(9):105-111. [17]戚永志,刘玉田.风光储联合系统输出功率滚动优化与实时控制[J].电工技术学报,2014,29(8):265-273. Qi Yongzhi,Liu Yutian.Output power rolling optimization and real-time control in wind-photovoltaic-storage hybrid system[J].Transactions of China Electrotechnical Society,2014,29(8):265-273. [18]王冉,王丹,贾宏杰,等.一种平抑微网联络线功率波动的电池及虚拟储能协调控制策略[J].中国电机工程学报,2015,35(20):5124-5134. Wang Ran,Wang Dan,Jia Hongjie,et al.A coordination control strategy of battery and virtual energy storage to smooth themicro-grid tie-line power fluctuations[J].Proceedings of the CSEE,2015,35(20):5124-5134. [19]桑丙玉,王德顺,杨波,等.平滑新能源输出波动的储能优化配置方法[J].中国电机工程学报,2014,34(22):3700-3706. Sang Bingyu,Wang Deshun,Yang Bo,et al.Optimal allocation of energy storage system for smoothing theoutput fluctuations of new energy[J].Proceedings of the CSEE,2014,34(22):3700-3706. [20]王成山,于波,肖峻,等.平滑微电网联络线功率波动的储能系统容量优化方法[J].电力系统自动化,2013,37(3):12-17. Wang Chengshan,Yu Bo,Xiao Jun,et al.An energy storage system capacity optimization method for microgrid tie-line power flow stabilization[J].Automation of Electric Power Systems,2013,37(3):12-17 [21]贺益康,胡家兵,徐烈.并网双馈异步风力发电机运行控制[M].北京:中国电力出版社,2012. [22]肖朝霞,樊世军,杨庆新.基于分层控制策略的光伏-蓄电池系统动态提高并网点功率因数[J].电工技术学报,2016,31(7):107-117. Xiao Zhaoxia,Fan Shijun,Yang Qingxin.Research on dynamically improving the power factor of PCC using photovoltaic-battery generation system based on hierarchical control strategy[J].Transactions of China Electrotechnical Society,2016,31(7):107-117.
2017, Vol. 32 
