含多分布式电源的孤岛微电网改进下垂控制策略

含多分布式电源并联运行的孤岛微电网，由于各线路阻抗差异，采用下垂控制策略无法实现无功功率合 理分配。为此，提出一种自调节虚拟阻抗下垂控制策略，通过无功功率调整虚拟阻抗，在不检测线路阻抗参数 的情况下补偿阻抗差异引起的输出电压差异，使各逆变器输出无功功率均等分配或按容量比分配。在Matlab / Simulink 中搭建含有两个分布式电源并联运行的孤岛微电网仿真模型，在两种情况下验证了改进下垂控制策略 能实现无功功率均分和按容量比分配。

Improved Droop Control Strategy for Islanding Microgrid with Multiple Distributed Generations

In an island microgrid with multiple distributed generations operating in parallel，due to the difference in impedance of each line，a reasonable control of reactive power can not be achieved using the droop control strategy． This paper proposes a self-adjusting virtual impedance droop control strategy，which adjusts the virtual impedance through reactive power and compensates the output voltage difference caused by the impedance difference without detecting the line impedance parameters，so that the output reactive power of each inverter is equally distributed or according to the capacity ratio． Using Matlab /Simulink，an isolated island microgrid simulation model with two distributed generations and parallel operation was built． In two cases，it is verified that the improved droop control strategy can achieve reactive power sharing and distribution according to capacity ratio．