Abstract:With the increasing acceptance, micro-grid, combined with distributed generation (DG), may be operated in grid-connected mode or islanding mode. In grid-connected mode, energy management is the main control objectives. While in islanding mode, to maintain voltage and frequency stable is the key point. Taking line impedance into account, PV droop control should be adapted in low voltage system. The PV droop control can share active and reactive power in islanding mode, but it will bring a great offset in voltage and frequency. The article proposes an improved opposite droop control (NPV): By adding feed-forward control to given power, secondary regulation of the voltage and frequency can be achieved. The NPV managed to do the job of both energy management in grid-connected mode and the secondary regulation of voltage and frequency in islanding mode. The results have been validated through simulations by PSCAD software and experiments.
孙孝峰, 吕庆秋. 低压微电网逆变器频率电压协调控制[J]. 电工技术学报, 2012, 27(8): 77-84.
Sun Xiaofeng, Lü Qingqiu. Improved PV Control of Grid-Connected Inverter in Low Voltage Micro-Grid. Transactions of China Electrotechnical Society, 2012, 27(8): 77-84.
[1] 梁有伟, 胡志坚, 陈允平. 分布式发电及其在电力系统中的应用研究综述[J]. 电网技术, 2003, 27(12): 71-75. Liang Youwei, Hu Zhijian, Chen Yunping. A survey of distributed generation and its application in power system[J]. Power System Technology, 2003, 27(12): 71-75. [2] 钱科军, 袁野, 周承科. 分布式发电对配电网可靠性的影响研究[J]. 电网技术, 2008, 32(11): 74-78. Qian kejun, Yuan ye, Zhou chenke. Study on impact of distributed generation on distribution system reliability[J]. Power System Technology, 2008, 32(11): 74-78. [3] 丁磊, 潘贞存, 丛伟. 基于有根树的分布式发电孤岛搜索[J]. 中国电机工程学报, 2008, 28(25): 62-67. Ding Lei, Pan Zhencun, Cong Wei. Searching for intentional islanding strategies of distributed generation based on rooted tree[J]. Proceedings of the CSEE, 2008, 28(25): 62-67. [4] Ackermant, Andersong, Sederl. Distributed generation: a definition[J]. Electric Power System Research, 2001, 57(6): 195-204. [5] Lasseter R, Piagi P. Providing premium power through distributed resources[C]. Proceedings of the 33rd Hawaii International Conference on System Science, 2000. [6] 王志群, 朱守真, 周双喜. 逆变型分布式电源控制系统的设计[J]. 电力系统自动化, 2004, 28(24): 61-66. Wang Zhiqun, Zhu Shouzhen, Zhou Shuangxi. Controller design for inverter-based distributed generation[J]. Automation of Electric Power System, 2004, 28(24): 61-66. [7] Ota T, Mizuno K, Yukita K, et al. Study of load frequency control for a micro-grid[C]. Australasian Universities Power Engineering Conference, 2007. [8] 王成山, 肖朝霞, 王守相. 微电网综合控制与分析[J]. 电力系统自动化, 2008, 32(7) : 98-103. Wang Chenshan, Xiao Zhaoxia, Wang Shouxiang. Synthetical control and analysis of micro-grid[J]. Automation of Electric Power System, 2008, 32(7) : 98-103. [9] 王成山, 肖朝霞, 王守相. 微网中分布式电源逆变器的多环反馈控制策略[J]. 电工技术学报, 2009, 24(2) : 100-107. Wang Chenshan, Xiao Zhaoxia, Wang Shouxiang. Multiple feedback loop control scheme for inverters of the micro source in microgrids[J]. Transactions of China Electrotechnical Society, 2009, 24(2): 100-107. [10] Laaksonen H, Saarip, Komulainen R. Voltage andfrequency control of inverter based weak LV network micro-grid[C].International Conference on Future Power Systems, Amsterdam, Netherlands, 2005. [11] Englear A, Soultanis N. Droop control in LV-grids[C]. International Conference on Future Power System, Amsterdam, Netherlands, 2005. [12] Josep M Guerrero, Nestor Berbel, Jose Matas. Droop control method with virtual output impedance for parallel operation of uninterruptible power supply systems in a micro-grid[C]. Proceedings of IEEE Applied Power Electronics Conference and Exposition, 2007.