Stability Improvement of a DC Microgrid Fed to a Multimachine Power System Using a STATCOM

This paper presents the stability-improvement results of a DC microgrid (MG) connected to a multimachine power system (MMPS) using a STATCOM connected at the point of common coupling (PCC). The wind farm and solar farm are connected to the DC bus of the DC MG through aggregated equivalent power-electronics converters and the DC quantity of the DC microgrid is converted into an AC quantity fed to an MMPS through aggregated equivalent voltage-source inverters (VSIs), step-up power transformers, and transmission lines. Small-signal stability of the studied system is performed using eigenvalue analysis. Dynamic simulations of the studied system under various disturbance conditions are also performed and analyzed. It can be concluded from the simulation results that the proposed STATCOM joined with the designed damping controller can render adequate damping to the studied DC MG fed to an MMPS under various disturbance conditions.