Abstract：To improve the applicability of conventional P-f and Q-V droop control methods of inverters in middle-voltage and low-voltage microgrids, this paper puts forward a novel control method of using virtual inductance and artificial output inductance in combination. A multiple feedback loop control strategy is proposed, the state-space equations are derived, and a complete small-signal model is established. Based on this, the matching principle of choosing virtual inductance and artificial output inductance is proposed. The inductance value is reduced significantly according to this principle, so problems of system stability and power loss are overcome. Simulation and analysis under linear and nonlinear load show that the proposed control strategy and parameter selecting method can not only enhance the output inductance of inverters, thus reduce the interference by line parameters, and also provide accurate load sharing, and inhibit circulating current effectively. This paper provides a new strategy for using conventional droop control in middle-voltage and low-voltage network.
基金资助:上海市自然科学基金（13ZR1444400）、上海市科委重大专项（13DZ1200403）和中央高校基本科研业务费专项资金（0800219169）资助项目; 本文采用的微网模型为未来可再生电能传输和管理网络（Future Renewable Electric Energy Delivery and Management,FREEDM）,由美国北卡州立大学与亚利桑那州立大学提出; 因其具有较强的稳定性和前瞻性,近年来一直获得美国国家科学基金会支持; FREEDM结构如图1所示
张明锐, 杜志超, 王少波. 微网中下垂控制策略及参数选择研究[J]. 电工技术学报, 2014, 29(2): 136-144.
Zhang Mingrui, Du Zhichao, Wang Shaobo. Research on Droop Control Strategy and Parameters Selection of Microgrids. Transactions of China Electrotechnical Society, 2014, 29(2): 136-144.
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