Assessment of the impact of a 10-MW grid-tied solar system on the Libyan grid in terms of the power-protection system stability

Abstract

Abstract The energy market in Libya is expected to face substantial changes in the next few years: electrical energy consumption will increase by 50% within the next 4 years. Therefore, there is a plan to gradually increase renewable energy sources in the power network by 2030 to 30%. Solar photovoltaic (PV) plants will play a significant role in the energy transition and the mix of energy sources in Libya. This article is a study conducted to investigate the challenges of power-flow management and power protection from integrating PV power plants into the Libyan power grid. In particular, a simulation model is built for the Kufra PV power plant (10 MW) with eight buses to assess the power network performance in terms of power quality such as voltage profile, power losses and harmonics. Furthermore, the impact of the PV plant on the short-circuit level and the power-protection system is presented under different operating conditions. The fault ride-through (FRT) is operated using standard ambient temperature and a wide range of irradiation intensity, and is verified by using the Libyan grid code. The results show that the integration of the PV plant into the grid has a significant impact on the short-circuit level and the FRT over the different fault levels and locations on the network. The initial period of the three-phase fault shows that the PV plant will be disconnected from the grid due to a decrease in the root mean square value voltages where the reactive and active power of the grid reach 938 MVAR and 261 MW, respectively. These results show that increasing the fault level will lead to an increase in injecting the active power. This work is considered the first extensive investigation into the challenges of modern power-flow management and power protection for the power network system in Libya.