Power Quality Improvement for PV Array Reconfiguration based Grid Tied System

This work presents an efficient control scheme for a two-stage single-phase grid-tied PV system under partial shading conditions. The primary objective of this work is to improve photovoltaic (PV) power plant performance under partial shade conditions by increasing the electrical energy generation feeding to the grid. Therefore, this work proposes a PV array reconfiguration algorithm to enhance the PV power under partial shading conditions. Additionally, an enhanced MPPT algorithm is employed to optimize power extraction from the total cross tied (TCT) PV array. Moreover, to improve the power quality under nonlinear load conditions for a grid-connected mode, a cascaded complex variable complex coefficient filter-based approach, along with a sliding mode current controller, is proposed. The proposed reconfiguration algorithm efficacy is validated through extensive MATLAB simulations by considering the various random shading patterns. Further, the injected grid current THD remains within the limits prescribed by the IEEE-1547 standard while ensuring unity power factor operation.