Online Application and Fast Solving Method for Critical Clearing Time of Three-Phase Short Circuit in Power System

• DOI: 10.12720/sgce.2.1.93-99
• Publication Date: 2013-12-31T02:24:11Z
• Authors: Ling-Yu Ren; Fang Tian; Jian-Feng Yan; Zhi-Hong Yu; Feng Su; Tao Wu
• Keywords: 0211 other engineering and technologies; 0202 electrical engineering, electronic engineering, information engineering; 02 engineering and technology; 7. Clean energy

For transient stability analysis, the direct method runs fast but with poor accuracy due to the over-simplification of component models; the time-domain simulation method is accurate but time-consuming and thus not suitable for online application. In this paper, results of the Potential Energy Boundary Surface (PEBS) method applied on the simulation examples and actual system calculation are analyzed, and the range of error is discussed. Via complementarity of direct method and time-domain simulation method, a new hybrid method is proposed: in the calculation of the critical clearing time (CCT), the result of the direct method is used as the initial value and then the time-domain simulation method is employed for further search, which can meet the requirements of online application in terms of accuracy and speed. Based on the power system online dynamic security assessment and early warning system (the PDSA), the fast solving method of three-phase short-circuit CCT is applied on the East China 500 kV power grid, and a detailed analysis of the result is presented. The engineering practice testifies the enhancement of CCT calculation in speed and accuracy.