PV Distributed-MPP Tracking: Total-Cross-Tied configuration of MICs to extract the Maximum Power under Partial Shading conditions

The Photovoltaic (PV) central inverter architecture comprises of various PV module configurations. The PV module configurations are vulnerable to shading effects and cause mismatching power losses. To reduce the detrimental effect of shading and mismatching on energy production, Distributed-Maximum Power Point Tracking (D-MPPT) architecture has been proposed. In this architecture, an individual DC-DC converter is integrated to each PV module/sub-module or short-string of PV modules to extract the maximum power. This topology is referred to as Module-Integrated-Converter (MIC). In conventional D-MPPT architecture, the output terminals of the MICs are connected in series or parallel configuration only. In series configuration, because of cross-coupling effects, the operating points of MICs are deviated from the Maximum Power Point (MPP). In parallel configuration, the cross-coupling effects are not present. But, the limitations of parallel configuration are lower conversion efficiency, lower voltages and higher currents, two-stage voltage conversion and also the use of isolated converters. To overcome the limitations of conventional configurations, this research paper proposes the Total-Cross-Tied (T-C-T) configuration of MICs. The performance of the proposed configuration is compared with the conventional configurations under various partial shading conditions. The proposed configuration extracts the maximum power from each PV module/sub-module or short-strings by minimizing the cross-coupling effects.