Dual-mode control of utility interactive microgrid

This article presents dual-mode control of a single-stage utility interactive microgrid based on a photovoltaic array and battery energy storage with improved power quality. For protection reasons, grid tied solar inverters are mandatory to shut down at loss of the grid. However, proposed multitasking microgrid is developed to provide energy to critical loads, even at disappearance of grid. The microgrid is integrated the BES and a PV array at DC link of voltage source converter of it to provide the harvested energy to local loads. In islanding, the amplitude and waveform of load voltages are maintained sinusoidal by the voltage controller. The transfer of modes (islanded to grid connected and vice-versa) is implemented using the synchronisation controller as per the accessibility of the grid. The instantaneous characteristic-based adaptive filter is utilised to control the microgrid in the grid-integrated mode. Moreover, a PV feed-forward term is incorporated in current control for injection of active power to the utility as well as to improve the dynamic response of microgrid. The phase detection controller estimates phase, frequency of utility and load voltages accurately and capability of disturbance rejection is improved. The effectiveness of PV-BES-based microgrid is validated experimentally.