Voltage stability as affected by discrete changes in the topology of power networks

An analysis of the effect of electrical network changes over the stability condition of a power system is presented. The study focuses on three different types of change: transformers with on-load tap changers, line outages and maximum excitation limiters in generators. For each of these changes, the static stability of load flow equations and the dynamic stability of the differential equations of the power system are analysed. As a byproduct of these studies, a strategy to detect voltage collapse problems is proposed