Abstract：There is limitation of traditional power theory of parallel operation of inverters based on the voltage of point of common coupling (PCC) in micro-grid system. An improved power theory of parallel system is deduced based on output terminal voltage of an inverter from a viewpoint of micro-grid autonomy operation. The “quasi power” variables are defined by linear combination and quasi active power and quasi reactive power are only related to the phase and amplitude difference respectively. A quasi-power droop control method for parallel connected inverters is proposed based on the improved power theory. The small-signal mathematical model of the parallel system is derived in a novel droop control scheme, which provides a theoretical basis for the parallel system performance analysis and droop coefficient design. The experiments were studied in the PV platform formed by two parallel connected three-phase inverters and the experimental results verify the correctness and feasibility of the proposed method.
张纯江, 王晓寰, 薛海芬, 阚志忠, 邬伟扬. 微网中三相逆变器类功率下垂控制和并联系统小信号建模与分析[J]. 电工技术学报, 2012, 27(1): 32-39.
Zhang Chunjiang, Wang Xiaohuan, Xue Haifen, Kan Zhizhong, Wu Weiyang. A Quasi-Power Droop Control of Three-Phase Inverters and Small Signal Modeling and Analysis of Parallel System in Micro-Grid. Transactions of China Electrotechnical Society, 2012, 27(1): 32-39.
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