Modified hybrid DC-DC boost converter with high voltage gain for renewable energy integration using GWO-DE parameter optimization

This paper presents a modified hybrid DC-DC boost converter topology with enhanced voltage gain capability for renewable energy applications, particularly suited for photovoltaic and micro-hydro power integration with high-voltage direct current (HVDC) transmission systems. The proposed topology incorporates a coupled inductor, switched capacitor, and voltage multiplier cell to achieve a significantly higher voltage conversion ratio compared to conventional boost converters while maintaining reduced voltage stress across the power semiconductor devices. A comprehensive steady-state analysis is performed under continuous conduction mode (CCM), and the voltage gain, current ripple, and efficiency expressions are derived analytically. Furthermore, a hybrid grey wolf optimizer-differential evolution (GWO-DE) algorithm is developed for the optimization of converter parameters, and a gradient-boosting regression surrogate is trained for rapid design-space exploration. The benefit of the GWO-DE optimization is quantified against both a classical analytical design and an exhaustive grid search, yielding a 2.7 percentage-point efficiency advantage over the analytical design and a 22-fold reduction in design wall-clock time relative to the grid search. The proposed converter achieves a voltage gain of 12.5 at a duty cycle of 0.65, with a peak efficiency of 96.8%. Extensive simulation results obtained in MATLAB/Simulink validate the theoretical analysis and confirm the superior performance of the proposed topology in comparison with existing high-gain DC-DC converter configurations reported in the literature.