Complete controllability of an N-bus dynamic power system model

As the computational and analytical methods for voltage stability assessmen t become more mature, voltage control becomes a primary issue. Power system s are large, nonlinear, and dynamic. During the last three decades, the app lication of differential geometry in the area of nonlinear control has prod uced significant results for the controllability analysis, This paper is co ncerned with the controllability problem of po,ver systems using the differ ential geometric methods. The modeled control devices include the mechanica l power input to generators, VAr compensation devices, and tap settings of the on-load tap changers. Conceptually, the main result of this research is the characterization and construction of a complete controllability region , within which a power system can be steered from one state to another by u se of piecewise constant controls. The results are obtained for two cases: 1) unbounded piecewise constant controls and 2) bounded piecewise constant controls. A complete controllability region identifies the limitations of t he available controls of a power system. The proposed method is believed to be significant since it is a new and systematic approach to the analysis o f power system controllability using a nonlinear control system model.