One of the most important issues in large industrial networks is continuity in sensitive loads feeding and lack of interruption in production line in order to prevent catastrophic damages. Because of this, these networks must be fed so that they have high reliability. These networks generally have interior power plant units which operates in parallel with utility grid in normal condition and feed sensitive loads when a disturbance occurred in feeding from utility grid. With consideration of this structure and relation of electrical grids with each other, doing dynamical studies in order to investigate behavior of these networks in emergency conditions is necessary. In this thesis, investigated network is Mobarakeh Steel Complex’s (MSC) power network which has an interior power plant unit with four synchronous generators and also fed via two lines from utility grid. So, for stability studies of this network, possible events are considered and dynamical behavior of synchronous generators is investigated in different conditions by simulations that have been done in DIgSILENT software. Then, in each scenario maximum critical clearing time for maintaining generators’ stability has been calculated. It should be noted that scenarios which are contributed to islanding of MSC regions, in addition to determining critical clearing time, load shedding program is considered in software and MSC power network stability in islanding condition has been investigated according that. Also, effect of some grid parameters and load modeling type on generators stability and fault clearance critical time have been investigated. Finally, solutions for improving stability of MSC power network are presented. Keywords: stability, possible events, critical clearing time, synchronous generator, industrial power network, dynamical studies
