Renewable energy sources are used as distributed generation (DG) sources in distribution networks. Inverter microgrids (MGs) in island operation are nonlinear systems with multiple dynamic modes. One of the main advantages of a microgrid is its ability to operate in islanded mode, where the DGs are responsible for providing both active and reactive power requirements by themselves. The distinguishing feature of distributed generation, with power electronic interfaces, which usually work as voltage source inverters, is the flexibility to provide controlled and high-quality energy. In this paper, the dynamic model of a microgrid based on inverter voltage sources in the first level of control is used. The behavior of a microgrid in the time domain is simulated and the performance of a microgrid is shown in three different modes. The inverter source control model including power control loops, voltage control and current control loops as well as the LC filter of the source output in the dq biaxial reference device are used. The simulation results show that with conventional dropout strategies, the active power distribution is done properly between sources, but it is not accurate enough to distribute the reactive power between the resources of a microgrid.
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