<p>This article presents a two-level control strategy for a battery-supercapacitor based DC microgrid. The microgrid consists of solar and wind sources as renewable inputs, and battery-supercapacitor units as hybrid energy storage. The supercapacitor pack absorbs transient components and alleviates current stress on the battery. The proposed control strategy utilizes an adaptive gain super-twisting algorithm (AGSTA) along with a super-twisting observer (STO) in the outer voltage loop, and super-twisting algorithm (STA) in the inner current control loops of battery and supercapacitor converters. The adaptive nature of gain in AGSTA provides faster control action with reduced chattering. The control technique provides faster dynamic response during sudden load changes. The simulation results verify the efficacy of the proposed control scheme in regulating the DC bus voltage during sudden variations in renewable inputs, reference voltage changes, zero solar irradiance and wind speed conditions, and abrupt load current variations at different supercapacitor voltage levels.</p>