Decentralized Control of Electrical Energy for Sensitive Areas as Inverter-Based Islanded Microgrid without Frequency Change

Supplying sensitive areas by utilizing various type of energy sources with decentralized control, in order to improve reliability and reach maximum autonomous operation capability, is essential. In addition, autonomous operation in the area as an islanded microgrid is an important step to have certainty of sustainable operation during black out or failure of stiff power system. in utilizing distributed generation inside microgrid, due to share loads by decentralized control on Voltage Source Converters (VSC), droop control method is employed. one disadvantage of droop control is the change in frequency respect to the change in output active power. In this paper, by introducing novel supplementary control system for droop control, the frequency changes in areas including sensitive loads are omitted. This goal is reached by floating reference frequency of VSCs according to output active power changes. Load sharing proportional to the units’ size, insensitive to connective line in microgrid structure and capability of changing the number of power units without changing the microgrid structure, are the features of the proposed control system. Simulation results in PSCAD are a confirmation of novel control system operation.