Enhanced grid-connected PV system with interleaved triple gain ultra boost converter and zebra optimised adaptive INC MPPT

Photovoltaic (PV) integration into the power grid is promptly progressing, propelled by continuous improvements in power electronics and Maximum Power Point Tracking (MPPT) strategies. An improved grid-connected PV system is introduced in this paper, integrating an Interleaved Triple Gain Ultra Boost Converter (ITGUBC) to enhance voltage gain and suppress ripple. It features a single-switch structure and employs three winding Coupled Inductor (CI) architecture. A Zebra Optimised Adaptive Incremental Conductance (ZOA-INC) MPPT algorithm is incorporated to optimise PV energy extraction. The proposed MPPT algorithm aims to achieve rapid adaptation, fast response, lower steady-state oscillations and high tracking efficiency. A bidirectional DC–DC converter is integrated with a Battery Energy Storage System (BESS) for power balancing and grid stability. The three-phase Voltage Source Inverter (VSI), regulated by a Proportional-Integral (PI) controller, which guarantees smooth and effective power feeding into the grid while maintaining low Total Harmonic Distortion (THD). Through extensive MATLAB simulations and hardware testing, the system is shown to sustain a stable DC-link voltage, deliver high power efficiency (98.92%) and enhance grid synchronisation. Comparative analysis with traditional MPPT techniques highlights the superior adaptability and tracking accuracy of the proposed method in dynamic scenarios.