Modeling of a large electric power system for optimal control of dynamic stability

This paper describes a general state-variable form of mathematical modeling which may be used to control the dynamic stability of a larger power system optimally. Based on the linearization about the operating point of the system, a complete model for dynamic stability control is obtained by combining transmission network equations, full-order synchronous machine equations, the exciter and voltage regulator model, torque equations, and the governor-hydraulic model in a matrix form which includes supplementary excitation and governor control signals. The complete model may then be simplified as a low-order model by neglecting the governor effects, exciter time constant, and all but the field flux linkage variations of the machines in order to reduce computational requirements.