ارزيابي پايه گذاري سيستم هاي قدرت به روش PEBS تكراري

POWER SYSTEM TRANSIENT STABILITY ASSESSMENT USING AN ITERATIVE PEBS METHOD

The Potential Energy Boundary Surface (PEBS) method is a fast and simple method for transient stability assessment of power systems using the Transient Energy Function (TEF) concepts and has no convergence problem. However, in some cases its accuracy is questionable and the critical clearing times obtained by using this method may be less or greater than the true values. To overcome this weakness, an iterative PEBS method is proposed in this paper, in which, the conventional PEBS method is firstly employed to compute an initial value for the critical clearing time, then the post-fault system trajectory is used to calculate a new critical clearing time. The simulation results on a 3-machine 9-bus and the 10-machine 39-bus New England test systems show that the iterative PEBS method gives more accurate estimate for the critical clearing time than that of the conventional PEBS method except for in the cases which the so-called "inter-area" mode stability phenomenon occur. The proposed iterative PEBS method is a fast method and can be used for fast transient stability assessment in energy control centers.