An Efficient Methodology for Study Mode Security Assessment of Power Systems for Large Disturbances

Abstract

An approach to the steady-state security assessment of large interconnected power systems for purposes of operational planning is proposed. Consequences of large disturbances are analysed on the basis of the successive solution of the load-flow problem for a set of characteri-stical postdynamic quasistationary states of the power system, where the influence of primary voltage and frequency control, the effects of necessary dispatch activities and the effects of system of automatic secondary control of frequency and tie-line powers flow is taken into consideration. For the load-flow models formed in this way, introducing some improvements and taking into consideration the physical nature of the phenomena under study, special fast decoupled solution procedures are developed. The efficiency of the methodology developed is tested in the steady-state security analysis of the power systems of Yugoslavia, for a series of characteristic large single and multiple disturbances.