Sliding Mode Control (SMC) has gained significant attention for maximum power extraction from solar photovoltaic (PV) panels under partial and rapidly changing weather conditions due to its effective dynamic duty-cycle regulation. Advanced versions of SMC, such as Single Integral Sliding Mode Control (SISMC) and Double Integral Sliding Mode Control (DISMC), offer improved tracking performance and enhanced PV efficiency under such conditions. The effectiveness of SMC depends largely on the proper selection of the sliding surface based on atmospheric variations, enabling precise duty-cycle control for the DC–DC boost converter. While SISMC can achieve the desired steady-state voltage accuracy, it struggles to meet the minimum settling-time requirement. To address this limitation, the proposed Double Integral Sliding Mode Control (DISMC) scheme incorporates an additional integral term, enabling faster convergence to the maximum power point (MPP) while maintaining minimal steady-state error. The DISMC provides a higher and more stable sliding-surface duty cycle for the boost converter, resulting in improved system stability, reliability, and enhanced PV efficiency even under inconsistent weather conditions. This paper presents the design and performance evaluation of the proposed DISMC-based MPPT scheme. A MATLAB/Simulink model is developed to validate the controller’s performance, and comparative analyses are conducted against conventional SMC and SISMC approaches. The results show that the proposed DISMC scheme achieves 99.10% efficiency with a significantly reduced settling time of 0.035 s, outperforming existing methods.