Brazilian defense plan against extreme contingencies

Abstract

This paper presents some of the short-term measures developed from the studies following the blackout in the Brazilian South/Southeast/Center-West power system in March 11/sup th/ 1999. The concept of security zones and network security matrix is introduced. A new PLC-based SPS was designed to create controllability zones. This new scheme was named security control and is triggered by network topological changes. The security control is fast acting, with clearing times around 200 ms. A typical security controller logic is presented, showing its benefits for the Brazilian interconnected power system.