Abstract

This chapter introduces concepts of DC MicroGrids exposing their elements, features, modeling, control, and applications. Renewable energy sources, energy storage systems, and loads are the basic components of a DC MicroGrid. These components can be better integrated, thanks to their DC feature, resulting in simpler power converter topologies, as well as the control strategy required for this application. A DC MicroGrid is developed as a realistic average model where the dynamics of the system are expressed in differential equations, including the nonlinearities of the model. A nonlinear distributed control strategy is developed for the DC MicroGrid, assuring the stability of the DC bus to guarantee the proper operation of each component of the MicroGrid. The energy storage systems are separated according to their time-scale operation, where a faster one controls voltage variations on the DC bus, and a slower one provides the power flow balance. The comparison with classical linear controllers is carried out to highlight the better performance of the nonlinear approach.