<p>This paper presents an intelligent feedback controller implemented via a Cuk converter for application in a DC nanogrid. The proposed controller is designed to maintain voltage stability and enhance the reliability of a regulated DC distribution bus in a renewable energy-based nanogrid operating in islanded mode. By integrating features of both linear and nonlinear control strategies, the controller exhibits robust performance in the presence of disturbances originating from both the source and load sides. Moreover, it offers a cost-effective and easy implementation. To eliminate the need for complex system modeling, the controller employs metaheuristic optimization techniques to fine-tune the gains of a PID controller, thereby achieving the desired dynamic response. Specifically, an adaptive genetic algorithm based on real-coded values (MARCGA) is proposed to enhance controller performance. This algorithm is benchmarked against three widely used metaheuristic algorithms: particle swarm optimization (PSO), the standard genetic algorithm (GA), and grey wolf optimization (GWO). The effectiveness of the proposed intelligent feedback controller is validated through extensive simulation studies, followed by experimental verification using a laboratory-scale prototype subjected to various dynamic operating conditions.</p>