Decentralized agent-based underfrequency load shedding

As part of the transition to a smart grid efforts are being made to decentralize control of electric power systems and modernize protection schemes that are currently in use. One specific application of distributed control is underfrequency load shedding (UFLS), which is used to restore the load/generation balance in a power system following unusual disturbances e.g.,loss of a generator. UFLS is currently performed automatically shedding preset amounts of load without situational awareness. The use of intelligent agents located at each transmission bus in the power system allows for an adaptive response to emergency loading conditions. The agents detect the onset of disturbances similarly to underfrequency relays currently used but dynamically determine the amount, location, and timing of load shedding based on the speed deviation of the synchronous generators and each machine's parameters. This approach maintains the speed of response associated with local control and incorporates intelligence into the process to tailor the response to the specific situation. The developed agent-based UFLS scheme is demonstrated in the IEEE 14 Bus System with a sudden loss of generation output following removal of key transmission lines. The amount of load shed is reduced considerably compared to a traditional UFLS scheme.