A DC Microgrid Coordinated Control Strategy Based on Integrator Current-Sharing

Energies

Liyuan Gao¹  Huisong Ren¹  Josep M. Guerrero²  Yao Liu³ 

[1] Department of Electrical Engineering, Shandong University, Jinan 250061, China;Department of Energy Technology, Aalborg University, DK-9220 Aalborg East, Denmark;Zhuhai Power Supply Bureau of Guangdong Power Grid Corporation, Zhuhai 519000, China;

关键词: DC microgrid;    DC bus voltage;    hierarchical/droop control strategy;    current-sharing;    power balance;   

DOI  :  10.3390/en10081116

来源: DOAJ

【 摘 要 】

The DC microgrid has become a new trend for microgrid study with the advantages of high reliability, simple control and low losses. With regard to the drawbacks of the traditional droop control strategies, an improved DC droop control strategy based on integrator current-sharing is introduced. In the strategy, the principle of eliminating deviation through an integrator is used, constructing the current-sharing term in order to make the power-sharing between different distributed generation (DG) units uniform and reasonable, which can reduce the circulating current between DG units. Furthermore, at the system coordinated control level, a hierarchical/droop control strategy based on the DC bus voltage is proposed. In the strategy, the operation modes of the AC main network and micro-sources are determined through detecting the DC voltage variation, which can ensure the power balance of the DC microgrid under different operating conditions. Meanwhile, communication is not needed between different DG units, while each DG unit needs to sample the DC bus voltage, which retains the plug-and-play feature of the DC microgrid. The proposed control strategy is validated by simulation on a DC microgrid with permanent magnet synchronous generator-based wind turbines, solar arrays and energy storage batteries, which can be applied to small commercial or residential buildings.

【 授权许可】

Unknown