Enabling self-healing microgrids by the improvement of resiliency using Closed Loop Virtual DC Motor and Induction Generator control scheme

摘要

Renewable energy based microgrids are emerging as a potential solution to augment the utility grid energy. However, their inherent dependency on static power electronic inverters lesions utility grid equivalent rotational inertia, which effects the system resiliency during uncertainties. This degrades voltage-quality, frequency-stability, and self-healing capacity of the microgrid. This typical challenge becomes major roadblock for the microgrids' integration with utility grid as per the explicit guidelines given by IEEE 1547. To address this challenge, this paper proposes the design of “Closed Loop Virtual DC Motor and Induction Generator Controlled Inverter (CL-VDCMIG-CI)” scheme. This mimics the behavior of a conventional electric machines based energy converter and emulates virtual inertia into the microgrid's operation. CL-VDCMIG-CI scheme uses DC motor and induction generator in virtual environment as models that controls the inverter continuously under all events. From results, it is observed that the proposed scheme retains the merits of power electronics and electric machines, thereby, improves the microgrid's resiliency by injecting virtual inertia.