An improved control strategy for reactive power sharing in microgrids

作者：Han Hua; Liu Yao; Sun Yao^*; Su Mei; Chen Huibin

来源：Proceedings of the CSEE, 2014, 34(16): 2639-2648.

DOI：10.13334/j.0258-8013.pcsee.2014.16.014

• Improved droop controls
• Microgird
• Reactive power sharing
• Synchronization signals
• Voltage bias

Due to the property of line impedance and other factors in microgrid, reactive power supplied by distributed generation units could not be shared accurately based on their conventional voltage droop gains. To improve the reactive power sharing accuracy of DG units and maintain the voltage quality in microgrid, the paper proposed an improved droop control of reactive power sharing strategy which was based on the synchronous thought. The proposed method is realized through the reactive power compensation operation and the voltage recovery mechanism. The reactive power compensation operation changes the voltage bias of the conventional droop characteristic curve, which is activated by the low-bandwidth synchronization signals from the central controller so that the reactive power sharing among distributed generation units is effectively improved. Meanwhile, the voltage recovery mechanism was employed to compensate the decline of DG output voltage in the process. In theory, this paper has proved the stability of the method. Simulations and experimental results also show that the improved droop controller can achieve good load active and reactive power sharing, and also has a good dynamic and steady-state performance.

• 出版日期2014
• 单位中南大学