Resilience Assessment in a Low Voltage Power Grid with Photovoltaic Generation in a University Building

Abstract

High integration of photovoltaic (PV) systems into the power systems causes negative or positive impacts. Typically, research considers the PV impacts on the RMS voltage, power losses, transformers and feeder stress, and power quality indicators. However, a generalising assessment of the electrical parameters and indicators (P&I) describes the power grid performance. It considers a complete holistic view of the real impacts that many events cause over the power grid operation. Therefore, this research proposes the resilience index in order to quantify and assess the impacts that the PV systems cause in low voltage. This scheme has four stages: i) P&I measurement, ii) P&I normalisation, iii) P&I weights assignment, and iv) resilience index quantification and assessment. The resilience scheme assessment has been applied in a low voltage university building with a PV system interconnected of 11.53 kWp. Monitoring has lasted for a month, with data acquisition every ten minutes. P&I monitored have been RMS voltage, RMS current, active, and non-active power, voltage imbalance, total harmonic distortion of voltage and current, and harmonic components of voltage and current. Results indicate that the PV system has positively affected the resilience index in the point of common coupling and floor four-node because the THDv, Vh, THDi, and Ih improved.