An optimal multivariable stabilizer for a multimachine plant

The authors propose an optimal multivariable stabilizer based on the generalized Heffron-Phillips model of a multimachine plant and on linear optimal control theory. The feedback function of the stabilizer is determined by minimizing a given quadratic performance index of the system. Nonlinear simulation results for different disturbance cases are discussed to demonstrate the capability of such a stabilizer to damp out intermachine oscillations. It is shown that because the optimal multivariable stabilizer is based on the optimal interactive feedbacks between machines and between all the output variables, rather than a single variable feedback to an individual machine, it can damp out the various intermachine oscillations quickly and optimally even for a large disturbance