双极性直流微网的分层控制策略

Hierarchical Control Strategy of Bipolar-Type DC Microgrid

分析了双极性直流微网的结构和优点,针对其结构和功率分配中下垂控制的问题,提出了一种由本地控制和二次调节组成的分层控制策略。本地控制包含中点电位控制和下垂控制,解决微网的中点电位不平衡问题和实现对微网中负载功率的初步分配;二次调节采用分布式补偿控制,消除线路阻抗的影响,实现负载功率的精确分配。对该分层控制策略进行了理论研究,并分析了系统的中点电位调节能力。在半实物平台上进行了相关实验验证,结果证明了该控制方法的有效性。

This paper analyses the structure and advantages of bipolar-type DC microgrid, and proposes a hierarchical control strategy which contains primary layer and secondary layer for the structure of the microgrid and the disadvantages of the droop control in load power distribution. The primary layer which consists of the neutral point potential control and the droop control solves the unbalance of the neutral point potential and realizes the initial distribution of load power in the microgrid. The secondary layer adopts a distributed compensated control to eliminate the influence of the line impedance and achieve the accurate distribution of load power. This paper does theoretical analysis of the hierarchical control and the adjustment ability of neutral point potential in the microgird. The effectiveness of this control is verified by the results of related experiments in the semi physical platform.