Tighter controls for busier systems

Power flow control difficulties on contract paths lead to flow controller development that furnished the foundation for the flexible alternating current transmission system (FACTS), making it possible to redirect power in real-time and instantaneous response to system disturbance. Several FACTS devices using thyristor technology were developed to adapt to the system needs, some of which are in the design stage, while others are already in operation. To use these devices along with on-line analysis of the system requires analytical tools that use real time information as well as dependable and wide area control center communication.