LMI-based Wide-area Robust Damping Control

This paper presents a new strategy for the design of wide-area robust controller (WRC) to damp the inter-area mode oscillations of power systems. Utilizing both local and remote non-delayed signals as controller inputs, mixed H₂/H_infin output-feedback design procedure is applied. Considering the specific power system construction, the remote feedback signal is chosen to associate with H₂ performance which is useful to handle stochastic aspects; whereas the local signal is chosen to associate with H_infin performance which is primarily concerned with model uncertainties. The feedback gain matrix is obtained through solving a family of linear matrix inequalities (LMIs). Experiments on a 4-generator test system demonstrate the effectiveness of the new controller and robustness with respect to variations of the system operating conditions. The results are also compared with the conventional PSS damping control