Novel analytical method for dynamic design of renewable SSG SPC unit to mitigate low-frequency electromechanical oscillations

Abstract

Grid operators require grid connected RGUs to provide specific dynamic features. RGUs must support dynamic performance of grid and operate in such a way to ward off new issues in grid. Recently, unfavorable oscillatory modes have appeared through grid connection of RGUs due to their dynamic interaction with other classical components of grid. Therefore, it is essential to develop a novel technique for dynamic design of RGUs to mitigate such risky oscillations. In this paper, a novel analytical method is proposed for dynamic tuning of a RSSG-SPC. Proposed method is based on mathematical analysis of derivative function of general damping ratio formula. The analytical results establishes generalized solutions that cover all operation mode of RSSG-SPC. Further on, solutions are implemented into dynamic model of RSSG-SPC to obtain clear, accurate and trustable criteria for tuning of virtual damping and virtual inertia. The dynamic tuning aims towards avoiding new oscillations in system and to mitigate natural oscillations of grid. Proposed approach was used for stability enhancement in high penetrated generation area and to support synchronization between interconnected areas in Kundur system. Proposed method was validated through modal analysis, time domain simulations and real-time evaluations which ensured that proposed approach is a reliable technique for dynamic design of RSSG-SPCs.