改进的孤岛微电网主从控制策略

Improved Master-slave Control Strategy for Islanded Micro-grid

采用主-从控制的微电网,其孤岛运行对“主微电源”的容量要求较高。为此,提出了一种改进型主-从控制策略。将“主微电源”的输出考虑为负载需求,即“主微电源”在瞬时补充系统功率缺额后,通过通信网络将“主微电源”的输出信息传递给“从微电源”,“从微电源”按照与各自容量成正比的输出比例分担“主微电源”的输出功率,间接减小“主微电源”的输出功率,从而减小系统对“主微电源”的依赖。仿真结果表明,在高渗透率的微电网中,系统能保持电压频率稳定,“主微电源”的输出被“从微电源”分担,且“从微电源”的功率与其容量成正比。

In an islanded micro-grid operating in master-slave control mode,the requirement for the master microsource is higher.To solve this problem,an improved master-slave control strategy is proposed,in which the output from the master micro-source is considered as load demand.After the system’s power unbalance is instantaneously compen?sated by the master micro-source,the output information of the master micro-source is sent to the slave micro-sources by a communication network.Accordingly,this output power is shared by the slave micro-sources according to ratios that are proportional to their own capacities,thus reducing the output power from the master micro-source indirectly.As a result,the system’s dependence on the master micro-source is reduced.Simulation results show that the system can maintain the voltage and frequency stably in a micro-grid with high penetrations of renewable energy.Moreover,the out?put from the master micro-source is shared by the slave micro-sources,whose outputs are proportional to their own ca?pacities.