System planning using existing flexibility

The primary purpose of this paper is to stimulate thinking about how the existing transmission system flexibility can be used. New electronic controller applications, based on thyristor technology, have helped to focus on the inherent flexibility in existing transmission systems. However, over the years, many techniques have been applied to take advantage of existing transmission system flexibility. This discussion provides examples of how system operation and reliability can be enhanced, with conventional equipment, by taking advantage of existing transmission system flexibility.