A concept of Robust Power System Security and its application under renewable energy sources penetration

Abstract

Penetration of large amount of renewable energy sources (RES) may introduce considerable uncertainties in power systems making difficult the planning and operation tasks. This paper proposes a new concept named "Robust Power System Security (RS)" in order to investigate power system security in the presence of uncertainties. RS region is defined as an area of power system operation in which the system is secure regardless of uncertainties in parameters such as RES outputs. When the size of the uncertainties is specified, RS region is identified. It is observed that the region tends to shrink and disappear as the uncertainty increases. Emerging problems concerned with security issues in future power systems are investigated.Simulations under large RES penetration are carried out using a three generators test system. Possible applications of the proposed concept toward real-time operation problems are discussed for keeping up the security. Index Terms-RobustPower System Security(RS), Renewable energy sources(RES), Transient stability, Uncertainties. Naoto Yorino (M'90) received the B.S., M.S.

A Study on the Power System Security under Future Uncertainties

“…Under the assumptions before the Great East Japan Earthquake, the penetration of photovoltaic power generation (PV) was targeted to reach 20-fold that of 2005 by 2020, and to further increase to 40-fold (approximately 53 GW) by 2030. Therefore, we proposed the new concept for security named Robust security, which can apply the conventional N-1 security in an uncertain environment [5][6][7][8][9][10]. On the other hand, PV has large fluctuations in its output depending on the irradiation conditions.…”

“…While the concept of decrease in security can be understood intuitively, quantitative evaluation was not available. Therefore, we proposed the new concept for security named Robust security, which can apply the conventional N-1 security in an uncertain environment [5][6][7][8][9][10]. Moreover, by utilizing this concept of Robust security, Robust dynamic security region (RDS), the region directly related to security evaluation among the four regions defined by Robust security, can be used as a quantitative evaluation index for N-1 security [11].…”