On multiple tap blocking to avoid voltage collapse

Abstract

This article discusses some aspects related to long term stability analysis of power systems. In particular, it is studied the effect of the tap changes in the instability process. For this sake, instability may be obtained as a consequence of a contingency, assuming the transient period as stable. In this sense, some discrete actions are taken in order to enhance the post–fault equilibrium point. These control actions may be temporarily effective, but eventually, may trigger the system collapse. In order to preserve the system stability, a technique to determine the instant to block the tap changes is proposed. Such a technique focuses on keeping the stability and recovers the maximum amount of voltage-varying load. The idea is tested using the IEEE-14 bus system.