Stability Assesment of a Multiple DG based Microgrid during Islanding Situation with Improved FA

This paper discusses stability assessment for a multiple Distributed Generators (DGs) based microgrid during islanding situation. Various DGs like Wind (WS), Photovoltaic (PV) and Diesel generator (DGN) is integrated in the considered microgird. The overall control design is addressed during the islanding scenario where the optimized solutions are calculated by Modified Firefly Algorithm (MFA). The proposed MFA has improved diversity to calculate the optimal stability in isolated grid condition. With various advanced feature, the MFA helps to converge faster with more accuracy. A Phase Locked Loop (PLL) based control are consider for the Voltage Source Converter (VSC) connected in the PV side and for the back to back converter connected with the wind generator. The overall gain optimization is applied at PV - VSC and the WS-Grid Side Converter (GSC). This improves the dynamic stability of the system by minimizing the error present in the controller during islanding. The effectiveness of the considered technique is verified in terms of power oscillation, stability margin. The results are compared with various other basic techniques.