A novel hybrid droop control strategy for <scp>DC</scp> microgrid with simultaneous consideration of operating costs and flexibility
Farnam Dehghani, Meghdad Tourandaz Kenari, Mohammad Agha Shafiyi
Abstract
There are various strategies for the contribution of generation resources in supplying loads of microgrids where one of the most common methods is the droop control technique that usually considers rated power or operating cost of resources for sharing power between units. However, considering the development of renewable resources, the importance of system flexibility is increased due to the variability and uncertainty of the generation of these units. In order to address this problem, this article introduces a flexibility-based droop method where the power-sharing is carried out according to the flexibility functions of units where flexibility criteria of generation resources including minimum power, ramp rate capability, and controllability are considered. Furthermore, a hybrid approach is proposed that combines flexibility-based and cost-based droop techniques using weighting factors. Therefore, it can simultaneously decrease system operating costs and increase system flexibility. The proposed method is applied to a sample microgrid, and the results are discussed. The simulation results demonstrate the applicability and effectiveness of the proposed approach.