Impact of Solar PV Integration on Power Quality of the JNEC Campus Distribution Network

Abstract

The increasing adoption of grid-connected solar photovoltaic (PV) systems has introduced new challenges related to voltage regulation and power quality in low-voltage distribution networks. This study investigates the impact of integrating a 240 kW grid-connected solar PV system into the electrical distribution network of Jigme Namgyel Engineering College (JNEC), Bhutan, using the Electrical Transient Analyzer Program (ETAP). An unbalanced load flow and harmonic analysis were conducted to evaluate the effects of PV integration on bus voltage profiles and total harmonic distortion (THD) under existing operating conditions. In addition, PV penetration studies at 25%, 50%, 75%, and 100% generation levels were performed to assess the network response under varying levels of solar generation. To evaluate future expansion, a 5 MW PV integration scenario was also simulated to examine the operational challenges associated with high PV penetration. The results indicate that the 240 kW PV system significantly improves the undervoltage conditions on the feeder supplied by the 250 kVA transformer while maintaining harmonic distortion well within the limits specified by IEEE 519 and the Bhutan Power Corporation (BPC) Low Voltage Distribution Code. However, the 5 MW scenario resulted in excessive voltage rise that required
additional voltage control measures. The implementation of a voltage regulator and Static VAR Compensator (SVC) effectively restored bus voltages to acceptable operating limits. The findings demonstrate that appropriately designed voltage regulation techniques enable reliable integration of distributed solar PV systems while maintaining acceptable power quality and supporting future renewable energy expansion in campus distribution networks.