Analysis on Research Status of Parallel Inverters Control Technologies for AC/DC Distribution Network
Cao Wenyuan1, Han Minxiao1, Xie Wenqiang1, Li Rui2
1. State Key Laboratory of Alternate Electrical Power System with Renewable Energy Source North China Electric Power University Beijing 102206 China; 2. China Electric Power Research Institute Beijing 100192 China
Abstract:Inverters are important interfaces for the interconnection of AC/DC power grids and the integration of renewable energy. With the development of DC power distribution technology and the increasing proportion of renewable energy access in power systems, the parallel operation control of inverters has become a key technical issue to maintain the stability of power system and improve the power quality. Firstly, three typical application scenarios of parallel inverters in AC/DC power distribution networks were put forward. Since the spatial distance between inverters is large and network parameters cannot be ignored, a model of parallel operated multi-inverter was then established, and the formula of the circulation between inverters was also derived. Furthermore, control methods for parallel inverters have been summarized. The problems and the related studies of power coupling, power sharing and power quality of the droop control were analyzed and reviewed. Finally, the control methods for parallel inverters suitable for AC/DC distribution network and the key problems to be solved were pointed out.
曹文远, 韩民晓, 谢文强, 李蕊. 交直流配电网逆变器并联控制技术研究现状分析[J]. 电工技术学报, 2019, 34(20): 4226-4241.
Cao Wenyuan, Han Minxiao, Xie Wenqiang, Li Rui. Analysis on Research Status of Parallel Inverters Control Technologies for AC/DC Distribution Network. Transactions of China Electrotechnical Society, 2019, 34(20): 4226-4241.
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