A Composite Strategy for Power Oscillation Damping Control Using Local and Wide Area Feedback Signals

Non-local measurements from wide area measurement systems can be used to synthesize feedback signals for FACTS or HVDC based power oscillation damping controllers. Although non-local feedback signals may have better damping influence than local feedback signals, they involve greater complexity and reduced robustness due to the possibility of partial or complete loss of communication. A composite control strategy is proposed in this paper, which uses both local and non-local feedback channels to achieve enhanced damping and improved robustness. Special local signals and their non-local equivalents are identified for series reactive and shunt real power injection devices, which facilitate the design of controllers with a simple structure and fewer parameters. Unlike modal speed signals, synthesis of these signals does not require an online eigen-solution. Case studies are presented which demonstrate the efficacy and robustness of this strategy.