Analytical Study of the Effects of Grid Resistance on Grid-Connected PV Systems: Modeling and Simulation

Abstract

Lot of issues associated with grid-connected PV system have appeared. One of the issues is the variations of grid impedance. In the traditional real and reactive power calculations, the resistance of the transmission line is usually neglected. But, the resistance of the distribution line may not be negligible. In a distribution network, the R/X ratio varies between 0.5 and 7. The variations in the resistance may affect the system stability. This study presents two models of a grid-connected PV system to address the effects of the grid resistance on the system. A mathematical model is built to determine the power equations, and then, power is calculated. MATLAB is used to implement the mathematical model. Also, a Simulation model is designed and simulated in SIMPLIS to calculate the power. A set of studies is performed for both models to determine the grid resistance effects. The results from both models are plotted and compared.