Influence of the power contribution of a grid-connected photovoltaic system and its operational particularities

This paper shows the relationship between the energy contribution of an 11.07 kWp grid-connected photovoltaic system and the particularities of its operation in parallel with a conventional electric distribution grid. Taking the experimental results as a starting point, it was verified that the contribution to the building's annual consumption is about 55% of the total load. The experimental results show how this kind of device influences the power quality parameters of the building: total harmonic distortion (THD), power factor (FP), and RMS voltage. The building power factor can be altered in a significant way depending on the system's production capacity and on the building load profile. Therefore, if a great number of PV systems are connected to the distribution grid, the reverse power flow coming from those systems can cause an increase in the voltage of a feeder and eventually cross the allowed upper threshold.