DC hierarchical control system for microgrid applications

作者：Lu Xiaonan^*; Sun Kai; Josep Guerrero; Huang Lipei

来源：Transactions of China Electrotechnical Society, 2013, 28(4): 35-42.

• Distributed characteristics
• Droop control
• Hierarchical control
• Hierarchical control systems
• Low-bandwidth communications
• Micro grid
• Micro-grid systems
• Parallel interfaces

In order to enhance the DC side performance of AC-DC hybrid microgrid, a DC hierarchical control system is proposed in this paper. To meet the requirement of DC load sharing between the parallel power interfaces, droop method is adopted. Meanwhile, DC voltage secondary control is employed to restore the deviation in the DC bus voltage. The hierarchical control system is composed of two levels. DC voltage and AC current controllers are achieved in the primary control level. At the same time, droop method for DC side is adopted to reach load sharing. Secondary control level is employed to restore the deviation caused by droop control. Common PI controller with low bandwidth communication is used in the secondary control level, which meets the requirement of the distributed characteristic in the microgrid system. In this paper, the detailed design method for each control level is introduced. Theoretical analysis of the low bandwidth characteristic of secondary control level is also realized. Theoretical results are validated by both simulation and experiment.

• 出版日期2013
• 单位清华大学