The objective of this research is to investigate new techniques for the control design of flexible AC transmission system (FACTS) devices for the mitigation of multiple interarea modes of oscillations. The focal point of the investigation is the design of damping controllers which are robust with respect to variations in loading conditions and system configurations. By modeling the changes in operating conditions as uncertainties, the robust damping controller design will be formulated as and H00 robust stability problem. A multi-modal decomposition based on synchronizing and damping torques will be used to provide an appropriate design structure to establish non-conservative uncertainty models. The proposal consists of the following research areas: (l) development of the multi-modal decomposition, (2) FACTS device siting and feedback signal selection, (3) development of uncertainty models, (4) computation of multi-modal decomposition in large power systems, (5) robust control design of a single FACTS device, and (6) robust decentralized control coordination of multiple FACTS devices. It is anticipated that a rigorous robust control design methodology based on synchronizing and damping torques for multiple swing modes will developed. The technique will appeal directly to power system control design engineers. The power system models will set up using the Power System Toolbox developed by the proposer. The control design process will be investigated using Matlab. Design examples will be solicited from utilities and equipment manufacturers.
