Development of a Coordinating Autonomous FACTS Control System

Abstract

Novel power-electronic FACTS devices (FACTS — Flexible AC Transmission Systems) can be used for fast, stepless adjustable power flow control and voltage control as well as for the improvement of stability in electrical power systems. Therefore, they are attractive especially for grid companies in liberalized energy markets. However, the uncoordinated use of FACTS devices involves some negative effects and interactions with other devices, which leads to an endangerment of the steady-state and dynamical system security. Up to now, these problems have led to a very restricted acceptance of the grid companies for FACTS devices. The present chapter gives an analysis of the necessary coordinating control measures in FACTS and expresses them as abstract coordinating rules. Based on that, an autonomous control system for electrical power systems with embedded FACTS devices is developed that realizes the necessary preventive coordination. With methods of computational intelligence the system automatically generates specific coordinating measures from the abstract coordinating rules for every operating condition of the power system without human intervention or control. That way an optimal utilization of the technical advantages of FACTS devices as well as the steady-state and dynamical system security is guaranteed. Interactions between the autonomous system and other existing controllers in electrical power systems are taken into consideration during the development process so that the autonomous system can completely be integrated into an existing conventional network’s control system.