A Nonlinear Droop Control Strategy Based on Bezier Curves in DC Microgrids

Droop control has been extensively explored to achieve desired power sharing among multiple sources in DC microgrids. However, conventional linear droop strategies have the trade-off between voltage regulation and load current sharing accuracy. To resolve this issue, researchers have developed piecewise linear strategies. While these methods enhance steady-state performance, they inherently exhibit discontinuous operational modes due to abrupt transitions between linear control segments. To address this limitation, this paper introduces a nonlinear droop control strategy based on Bezier curves to smooth the piece-wise linear droop curve. Compared with the piecewise droop control strategy, this method can provide a faster dynamic response. In addition, a current sharing strategy is proposed to simplify the calculation process of current sharing parameter design. Finally, simulation results validate the theoretical analysis.