ADVERSE IMPACT OF REDUCED INERTIA CONSTANT ON TRANSIENT STABILITY IN MANGYSTAU POWER SYSTEM

Abstract

Climate change and growing environmental risks are accelerating the global shift toward renewable energy sources (RES), but this transition brings new challenges for power systems. Replacing conventional generation with RES reduces system inertia, which can negatively affect dynamic stability.This article analyzes how reduced inertia impacts the stable parallel operation of the Mangystau power plant and the Unified Energy System of Western Kazakhstan. The study focuses on electromechanical transients in scenarios with high-RES penetration and generator outages. Five inertia scenarios were modeled under two initial operating conditions using PowerWorld Simulator 23, evaluating the effects of a three-phase fault with unsuccessful reclosing on 220 kV lines.The results show that lower inertia significantly weakens dynamic stability, creating potential risks for secure power system operation. The findings highlight the need to account for inertia when planning RES integration and underscore the importance of developing new principles of emergency automation. These results demonstrate the critical importance of maintaining sufficient system inertia to ensure reliable and stable power system operation under increasing RES penetration.