An Integrated Control Strategy Adopting Droop Control with Virtual Inductance in Microgrid

Jianjun Su, Jieyun Zheng, Demin Cui, Xiaobo Li, Zhijian Hu, Chengxue Zhang

Dezhou Power Supply Company, Shandong Electric Power Group Co., Dezhou, China.
School of Electrical Engineering, Wuhan University, Wuhan, China.

DOI: 10.4236/eng.2013.51B008                

Abstract

As there exists sorts of distributed generators in microgrid, an integrated control strategy containing different control methods against corresponding generators should be applied. The strategy in this paper involves PQ control and droop control methods. The former aims at letting generators like PV output maximum power. The latter stems from inverter parallel technique and applies to controlling generators which can keep the network voltage steady to make the parallel system reach the minimum circulation point. Due to the unworthiness of droop control applied in low-voltage microgrid of which the impedance ratio is rather high, the paper adopts the droop control introducing virtual generator and virtual impedance. Based on theoretical analysis, simulation in Matlab is also implemented to verify the feasibility of the strategy.

Keywords

Microgrid; Integrated control; PQ control; Droop control; Virtual impedance

Conflicts of Interest

The authors declare no conflicts of interest.

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