This paper proposes a robust control scheme to improve the integration of variable energy sources such as renewables into a DC bus distribution microgrid. The model of the controller is developed and analyzed with simplification of parameters and keeping the effect of the multiple loads and sources connected in parallel as an uncertainty. Various simulated scenarios are used to show the performance of the controller with variations on references and disturbances, isolated and paralleled. The results obtained by analysis of a linearized model allows to show the robustness of the model and the effect of internal current and voltage loops to provide stability.