Pelican optimization-driven two-degree-of-freedom IMC design for output voltage regulation of SEPIC converter

Single-ended primary-inductor converters (SEPICs) face output voltage regulation challenges owing to right-half-plane zeros and complex fourth-order dynamics, which severely restrict their control implementation. Traditional methods struggle to provide fast and stable regulation during sudden disturbances, especially when the input or load undergoes significant changes. Therefore, specialized controllers are required to address the slow response of the system and ensure stability over the operating range. This study presents a modified two-degree-of-freedom internal model control (MTDF-IMC) strategy for the output voltage regulation of SEPICs by unifying the IMC and model order reduction. In the proposed work, the proposed MTDF-IMC structure develops an internal model for control design, which is derived by reducing the fourth-order SEPIC through Padé approximation. The proposed control strategy incorporates the Pelican optimization algorithm to optimize the disturbance rejection performance and set-point tracking. The effectiveness of the proposed controller is assessed using MATLAB simulations across two operating scenarios of SEPIC. The results validate the efficacy of the proposed methodology and emphasize its potential for practical applications in power electronics, where precision and computational efficiency are vital.