Effects of the Intermittent Injection from a Photovoltaic Power Plant on the Frequency of the Senegalese Grid: Case Study at Bokhol

Abstract

This work presents a study of the impact of the power injection of a photovoltaic (PV) power plant on the frequency of the electrical network. We took the case of the solar PV plant of Bokhol connected to the electrical network of the national electricity company of Senegal (SENELEC). We have treated the case of two days: the day of January 10, 2021 and that of December 23, 2021. The study is carried out on the basis of the frequency constraints imposed by SENELEC to the PV plant manager. The plant remains connected to the grid as long as the power injection does not cause frequency variations outside the range of 49.7 Hz and 50.3 Hz. The results of the study first show the correlation that exists between PV power and climatic parameters such as irradiation, temperature and wind speed. The results also showed that the variations of the injected power strongly contribute to the instability of the electrical network through a frequency disturbance. This causes the PV plant to be disconnected from the grid. This is the case during the day of January 10, 2021, when the plant is disconnected from the grid from 8:30 to 11:30. During this period of the day, the frequency exceeded the permissible limit of 50.3 Hz. The same scenario is also observed during the day of December 23, 2023 during which the power plant is disconnected twice.