Assessing the Impact of Integrating Solar PV System using the Equal Area Criterion Method

Abstract

The impact of previous energy crisis gives an insight into what happens when the oil price crashes. Μany countries were affected due the slow reaction in boosting the economic growth in key sectors such as oil-importing activities and the economic restructuring progress to face the challenges. But the present energy crisis resulting from the COVID-19 pandemic period and closure of many borders, has encouraged power distributors and generators to have recourse to renewable energy for grid integration. Countries such as USA, Germany, Italy, Spain and India are moving towards increasing the share of renewable energy on the grid. The increasing use of solar power systems over the past few years is being favoured for the decarbonization process. The percentage growth in integrating solar PV energy is forecasted to reach 23% in the future. This widespread application of renewable power energy sources (RES) such as wind and solar power comprise of many challenges namely power quality and stability. With this consequent increase in RES, synchronous generators are being displaced and replaced by power electronics grid interface, which reduces the overall rotating masses, hence the system inertia. Stability study in the presence of renewable energy is therefore an important aspect to be considered to meet the required power quality of the grid. This paper brings forward the use of equal area criterion (EAC) method for assessing the stability of the power system network with presence of renewable energy such as solar energy system in the generation portfolio. EAC provides an effective visual and analytical approach for transient stability analysis. The investigations have been performed within the steady and transient conditions in form of a 3-phase fault. The modelling and analysis were carried out using MATLAB/Simulink. Calculation of the critical clearing time (CCT) for stability assessment is the main contribution to knowledge. The increase in the CCT confirms that the Solar PV penetration to the grid will improve the transient characteristics of the national grid network.