ENHANCING FREQUENCY STABILITY FOR ISLANDED POWER SYSTEMS USING HIERARCHICAL CONTROL SYSTEM

Abstract

Recently, the power grid on isolated islands integrates renewable energy sources available on the island, such as wind and solar power in order to utilise the green energy and to reduce greenhouse gas emissions from diesel generators as well as protect the environment. However, the power generated from these renewable sources depends on the weather, which can make the power grid unstable. Sudden weather changes can cause significant fluctuations in the power generated, affecting the stability of the system's frequency and voltage. In the worst-case scenario, this could lead to a grid collapse due to protective devices tripping to maintain stability. Researchers and experts are looking for ways to improve the stability of the power system, especially the voltage and frequency. One of the most effective solutions is using a Battery Energy Storage System (BESS). To enhance the frequency stability of the island's power system and ensure safe and reliable operation, the authors propose a solution that combines BESS and diesel generators using a hierarchical control method. This paper aims to evaluate the effectiveness of this solution by simulating its application on a microgrid, specifically the Phú Quý Island's power system, using the Electrical Transient and Analysis Program (ETAP) software.