Power flow control of microgrid with wind generation using a DSTATCOM-UCES

High penetration of wind power in microgrids causes fluctuations of power flow and significantly affects the power system operation. This can lead to severe problems, such as system frequency oscillations, and/or violations of power lines capability. With proper control, a distribution static synchronous compensator (DSTATCOM) integrated with ultracapacitor energy storage (UCES) is capable to significantly enhance the dynamic security of the power system. This paper proposes the use of a UCES system in combination with a DSTATCOM as effective distributed energy storage for stabilization and control of the tie-line power flow of microgrids incorporating wind generation. A full detailed model of the DSTATCOM-UCES device is presented and a novel three-level control scheme is designed, comprising a full decoupled current control strategy in the d-q reference frame and an enhanced power system frequency controller. The dynamic performance of the proposed control schemes is completely validated through digital simulation in MATLAB/Simulink.