A Trend-Oriented Power System Security Analysis Method Based on Load Profile

Conventional power system security analysis based on multiple case studies cannot predict all operational states and hence neither guarantees an adequate security margin nor an economical operation for the power system. Based on the trend analysis method which is used in the field of economics, this paper introduces the concept and a methodology for “trend security analysis” of power systems. This method utilizes the load profile forecast and the contingency occurrence probability and determines the system security trend in the subsequent time window. Based on a recursive algorithm which is developed by utilizing the higher order derivatives of power flow equations, this paper also presents a method for fast determination of the trend variations of the system states and security indices. Three IEEE test systems are used to demonstrate the applications of the proposed concepts, evaluate their performance and verify their accuracy.