A Phase-Shifting MPPT to Mitigate Interharmonics From Cascaded H-Bridge PV Inverters

Interharmonic is an emerging issue in photovoltaic (PV) systems. It has been revealed previous studies that the maximum power point tracking (MPPT) control one potential source for interharmonics. In cascaded H-bridge (CHB) PV inverters, if MPPT perturbations of CHB cells are in-phase, sum voltages all will oscillate with a higher amplitude, leading to amplification interharmonics delivered grid. To address this issue, phase-shifting (PS-MPPT) method interharmonic mitigation proposed paper. By properly shifting phase-angle perturbation each cell, oscillation equivalent total dc voltage can be effectively mitigated, and turn, suppressed large extent. The PS-MPPT scheme demonstrated on inverters through simulations experimens. implementation generalized n-cell further discussed. Moreover, hybrid also developed improve performance. Simulation experimental results have validated effectiveness terms suppression.