Direct- and Quadrature-Axis Equivalent Circuits for Solid-Rotor Turbine Generators

Direct- and quadrature-axis equivalent circuits are developed for solid-rotor turbine generators. The equivalent circuits model, in considerable detail, important current-carrying paths in the rotor in addition to the excitation winding. Impedance equations are formulated so that a valid representation can be obtained over a wide range of frequencies. Operational solution of the equivalent circuits provides a powerful means for accurate analytical description of generator performance during many types of transient conditions, such as faults and other system disturbances, excitation system forcing, and asynchronous operation. In addition to providing improved accuracy of representation of generator terminal characteristics, solution of the circuits provides a wealth of valuable generator design information.