A study on mechanism of voltage collapse based on the theory of transversality of equilibrium points

Abstract

A power system will experience voltage collapse when a system load parameter is over a certain critical value. The critical operation point corresponding to voltage collapse is recognized as the system saddle-node bifurcation point, which is also the turning point in the P-V curve. In this paper, we study the mechanism of voltage collapse based on the circuit equations and their solution manifolds. The research shows that the fundamental reason for the occurrence of voltage collapse is due to the non-transversal intersection between solution manifolds of the injection branch equations and the linear electrical network equations in the bus voltages and injection currents spanned space. Numerical examples support the conclusion very well. The paper also proves that this non-transversal intersection exactly corresponds to the static state bifurcation point, i.e. the critical point of voltage collapse. © 2003 Elsevier B.V. All rights reserved.