Stabilization methods of DC Microgrid with distributed control considering communication delay

Abstract

When designing a controller in DC Microgrid, normally the communication delay, which may cause system instability, has not been taken into account. In this paper, the effect of communication delay on system stability is studied based on a distributed control strategy, and a novel delay-independent stability criterion for the system with time-varying delays is proposed. To obtain a less conservative condition for system stability, the delay-dependent stability is analyzed, and the delay upper bound is given. Specifically, an approach used to define the feasible regions of control parameters is derived to ensure the system stability under the condition of delay. The research shows that the proposed method provides a wider delay boundary, which makes the system safer, more reliable and stable. Finally, simulation and experimental results verify the effectiveness of the proposed stabilization methods.