Modeling and Performance Assessment of an Efficient Photovoltaic based Grid-Connected Inverter System with Integration of LCL Filter

Power converters are required to modify the intermittent power from renewable sources into smooth and stable output. However, the power electronic based components which are utilized in the converters along with their pulse width modulation property can create power quality issues. Among all of them, one of the critical aspects is regarded as harmonic distortion. Thus, harmonic filters are essential for the purpose of grid interconnection to reduce the total harmonic distortion and hence to improve the overall power quality of the network. Filters which are based on the combination of inductors and capacitors show promising results in grid-connected mode thereby having increased value in industrial application considering the additional benefit of its relatively low cost of implementation and maintenance. This paper proposes an innovative inductor-capacitor-inductor (LCL) filter for a photovoltaic (PV) based grid-connected system. For this purpose, a PV based renewable energy source is modelled and its output is carefully monitored. Then the proposed LCL filter is connected for the harmonic distortion control. The LCL filter parameters are adjusted for the achievement of high performance while considering the grid conditions and essential load requirements. Several case studies have been performed to validate the proposed Grid-Connected Inverter System (GCIS). Numerical analysis has been done in MATLAB/Simulink. The results have shown a better filter performance under the designed switching frequency and rated power condition.