Enhanced PV Grid-Connected System with Adaptive MPPT and Harmonic Mitigation Capability using High Gain Interleaved Cuk Converter

Solar energy is pivotal in renewable energy systems (RES) due to its clean, sustainable nature, and its rising demand, fuelled by escalating electricity costs, underscores its significance. Photovoltaic (PV) arrays, central to solar energy harnessing, exhibit varying output characteristics influenced by environmental changes. Maximum Power Point Tracking (MPPT) approaches are essential for optimizing power extraction. Considering current MPPT techniques, a new Incremental Conductance (INC) MPPT algorithm was developed, integrating adaptive variable step size, is introduced. This algorithm dynamically adjusts step size through a coefficient, eliminating the need for user-defined constants, thus streamlining PV system design. This study proposes an Interleaved Cuk Converter (ICC) to mitigate input current ripple and enhance transient response. Additionally, the linear relationship between MPP voltage and open-circuit voltage is used to generate a tuning strategy for initial step sizes. A PI controller controls the inverter gating sequence and the proposed system is validated through MATLAB simulation. Comparative analysis reveals the proposed INC method's superior dynamic response and steady-state performance, especially during extreme irradiance fluctuations. The proposed converter achieves a efficiency of 92.47% and proposed controller achieves accuracy of 90.64%.