Stability Analysis of Grid with High Renewable Energy Sources Under Uncertainty Conditions

Renewable Energy Resources (RES) have been become an inevitable choice for the future. However, RES can decrease the inertia of grids to which they are connected. Moreover, their power generation depends on weather conditions, making it intermittent and uncertain. These two inherent characteristics of RES negatively impact the stability of connected power systems. Forecasting RES power output and loads demand is one of the most effective solutions to improve stability of grids integrated with high penetration. However, predictive methods have not yet achieved perfect accuracy. To address the gap, this paper presents a novel stochastic simulation based on forecasting, form which operators can identify extreme scenarios and prepare solutions to ensure the safety and reliability of grid operations in these situations. This paper introduces stochastic simulation techniques, demonstrating their application in identifying severe scenarios based on global stability of a grid. Furthermore, the study proposes solutions to enhance overall stability of the grid after identifying these extreme conditions.

I. Introduction

Currently, fossil fuels still dominate our energy consumption. However, the depletion of these resources and their environmental consequences (e.g., greenhouse gas emissions, pollution) drive the search for and exploitation of alternative energy sources. Wind and solar energy have become one of the best choices due to their availability. Multiple nations worldwide have set targets to utilize Renewable Energy Sources (RES) in the near future. For instance, the French Government's Energy Transition for Green Growth (TECV) aims for at least 40% of electric energy to be supplied from RES by 2030 [1]. Nonetheless, the power output of RES, such as Photovoltaic units (PVs) or Wind Turbines (WTs), depends on weather conditions like solar irradiation and wind speed, making their power production intermittent. Additionally, most RES are connected to grids via power electronic inverters, resulting in no inertial contribution from the RES to the grids. This means that the higher the penetration of RES in a power system, the smaller the system's inertia.