Distributed prescribed time-based secondary voltage and frequency recovery control of microgrids

For islanded microgrids (MGs) with inverters, this paper proposes a secondary control framework combining prescribed-time voltage and frequency recovery, and further enhances it through time funnel constraints. Based on the standard droop control at the primary layer, the prescribed-time control strategy is designed with an error-related scalar transformation. An auxiliary function is constructed for composite nonlinear dynamics, and neural networks are introduced to approximate the dynamics. The proposed control strategy not only ensures accurate active power sharing but also allows the user to specify the convergence time while maintaining a tighter error envelope. A hardware-in-the-loop test consisting of four distributed generators is conducted, and the results demonstrate the effectiveness of the proposed control strategy.