Control Strategy for Inverter Based Micro Grid

Micro Grid (MG) may be treated as a low voltage network of local distributed energy sources and local loads. Micro Grids (MG) are usually a small scale power supply networks with total installed capacities around a few hundred kilowatts to few megawatts. The main aim of micro grids are supplying power to remote place or village by utilizing the available local resources, where there is no grid connection and also micro grids can be designed for uninterruptable power supply with high quality power to sensitive loads in a certain area. Micro Grid (MG) can be operated in two modes one is grid connected and another one is islanded mode. Each mode has its own control strategies. In this project islanded mode is mainly focused. In previous method virtual output impedance method is used. By using this method the derivative of output current may amplify the magnitude of harmonic currents. Due to this power supply is interrupted and the power sharing among the inverters is not satisfactory. To overcome above problem a new control technique is proposed. This method contains Second Order General Integrator (SOGI) and virtual output impedance. This method increases the impedance certainly and limits the circulating currents (harmonic currents) in the inverter. The main objective of this project is to limit the circulating currents (harmonic currents) in the inverter and proper power sharing among the inverters in islanded mode by using proposed control techniques. The proposed method is simulated in MATLAB/SIMULINK environment.