Coordinated power control strategy based on primary-frequency-signaling for islanded microgrids

In a flexible microgrid, the power regulation of each electronic-converter-based unit should be not only determined by the load demand, but also controlled according to the power and energy available in each unit. This paper proposes a coordinated control strategy in which each unit can operate in different operation modes taking into account the resource limitation. Firstly, a Primary-Frequency-Signaling (PFS) is introduced to realize coordinated control between units in a distributed way. Then the whole control structure of system is descripted in detail, which includes innerloop control with virtual impedance and primary control based on droop method for modes changes. The four modes changes for operation of ESS and RES are illustrated. Finally, simulation results will be presented to demonstrate and validate the proposed control strategy.