Reduced-order models for the dynamics of a single-machine power system via balancing

The method of reduction based on balanced state space models is applied in this work to a single-machine infinite-bus system. In this representation the state variables are ordered with respect to their input-output contributions. States with important contributions are retained in the reduced model. The natural order of the reduction scheme is dictated by the relative magnitudes of the invariant singular values (SVs) of the state space model. Several reduced-order models of a single-machine power system are produced. In many situations the reduced-order model consists of one or more completely decoupled subsystems, the orders of which are dictated by the relative separations of the SVs. A comparison is made with other known methods to test the performance of the technique. Satisfactory results are obtained with the balanced reduction technique for the selected test case studies.