حسن بیورانی

With increasing the presence of Microgrids (MGs) in the power systems, it has become urgent to investigate the MG stability during transient faults. This study investigates the transient stability analysis of a MG supplied by multiple inverter interfaced distributed generations (IIDGs) during fault. The transient stability of a MG is highly depends on the IIDGs control strategy. A MG, simulated on Matlab/Simulink, including three IIDG and two local loads connected to the IEEE 37-node distribution system is considered as test system. Simulation results show that the MG may lose its stability due to the IIDG’s transient over-currents under fault conditions. By adding a transient current control loop to the voltage source inverter (VSI) control strategy, the IIDG output currents are limited during fault. In the connected mode, an external fault is applied to the MG. With appropriate tuning of the transient loop controller coefficients, the good performance and fast dynamic of the proposed control approach is shown. The simulations results show the transient stability enhancement of the MG obviously.