Power electronics-based T&D controllers technology developments

Power electronics is one of the fastest changing "enabling infrastructure technologies" in electrical engineering. It has made and continues to make a significant impact on power and energy infrastructures, which constitute one of the pillars of the foundation of our society and the rest of the world. Power electronics-based transmission controllers are the key elements for transforming a transmission system from being a "passive" to be an "active" system, i.e., flexible, controllable and securely utilizable up to its thermal capacity. Currently, the power electronics-based transmission controllers are at a technological crossroad towards improving operating reliability, lowering development costs, and introducing innovative technical functionality and controllability options. This paper presents an overview for technology evolution of transmission & distribution controllers, from thyristor-based technology to the voltage-sourced converter-based technology. The paper also outlines a "roadmap" for future developments.