  In this paper, we propose an approach to determine the optimal operation
strategies for a PV-diesel-battery microgrid covering industrial loads under
grid blackouts. A special property of the industrial loads is that they have
low power factors. Therefore, the reactive power consumption of the load cannot
be neglected. In this study, a novel model of a PV-battery-diesel microgrid is
developed considering the active as well reactive power of the microgrid
components. Furthermore, an optimization approach is proposed to optimize the
active as well reactive power flow in the microgrid for covering the load
demand while decreasing the power consumption from the grid, minimizing the
diesel generator (DG) operation cost as well as maximizing the consumed power
from the PV-array. It has been found that the proposed operation strategy
induces a huge reduction of the consumed energy cost and the PV curtailment.
