Mobile QR Code QR CODE : The Transactions of the Korean Institute of Electrical Engineers
Title Estimation of Critical Inertia of Korean Electric Power Systems Based on Transient and Small-Signal Stabilities
Authors 백종오(Jong-Oh Baek) ; 정인주(In-Joo Jeong) ; 하정민(Jung-Min Ha) ; 맹창엽(Chang-Yeop Maeng) ; 권오근(Oh-Geun Kwon) ; 이배근(Bae-Geun Lee) ; 김수배(Soobae Kim)
DOI https://doi.org/10.5370/KIEE.2019.68.9.1100
Page pp.1100-1108
ISSN 1975-8359
Keywords Critical inertia; Transient stability; Small-signal stability; Renewable energy source; Korean power systems; Critical clearing time; Damping ratio
Abstract The increase of inverter-based renewable energy sources reduces inertia constant of power systems and the loss of the system inertia may cause power system stability problems. To ensure a secure energy delivery system, these problems should be analyzed thoroughly from various perspectives about power system stability. This paper presents the estimation of the critical inertia of Korean power systems, which is the minimum amount of inertia required to maintain power system dynamic securities. The estimation has been made by gradually reducing the system inertia of Korean power systems and then by analyzing the change of dynamic securities in terms of transient and small signal stabilities. In the transient stability aspect, the decrease of critical clearing time(CCT) has been analyzed with four different reduced inertial models of Korean power systems. With the small signal stability perspective, the change of the system damping ratio has been studied. Based on the results from the stability studies, the critical inertia has been determined and it can be considered as the indirect limit of renewable energy shares in Korean power systems.