<p>Switching-based power converters are vital in industrial and laboratory applications in modern power electronics. Among various topologies, the DC–DC boost converter (DDBC) is particularly significant due to its inherent non-minimum phase behavior caused by a right-half-plane zero. This work presents the design of a robust feedback controller for voltage regulation of the DDBC using a novel structure, a feedback proportional–integral–derivative (PID) controller cascaded with a fractional-order filter elucidated by the internal model control (IMC) framework. This configuration, referred to as fractional filter PID, introduces an additional degree of freedom through the fractional-order parameter, offering greater tuning flexibility than conventional integer filter-based PID structures. The tuning strategy leverages the robustness criterion of maximum sensitivity, enabling a balanced trade-off between performance and robustness. A systematic method determines controller parameters by minimizing the integral absolute error (IAE) under specified robustness constraints. Moreover, a feedback plus feedforward control scheme is incorporated to enhance disturbance rejection capabilities. The results demonstrate that the proposed controller significantly improves performance and is more robust than existing methods in the literature, making it a promising solution for robust voltage control in non-minimum phase DC–DC converters. Finally, the proposed method is validated through an experimental setup using a real-time digital simulator (OPAL-RT-5600).</p>