Prescribed Performance-Based Secondary Control for DC Microgrid

In this article, based on the prescribed performance control approach, a distributed secondary control scheme is developed for an islanded DC microgrid, to achieve current sharing among the converters and voltage regulation of the DC bus while guaranteeing the prescribed transient performance of the system. With the proposed controller, the evolution of both the bus voltage error and the current sharing error can be constrained within a predefined imposed bound. In this way, the safety of the electrical devices can be ensured and the dynamic performance of the microgrid can be improved. In addition, the controller is quite simple for implementation without sampling and delivering the information of the DC bus voltage. Simulation studies and experiment tests are carried out to demonstrate the effectiveness of the proposed secondary control scheme.