Transient Behavior in Electric Machines Models
Basic theory of electrical machines (flux linkage equations, development of torque and voltage). Direct Current machines theory (equations of torque and voltage, dynamic characteristics, linearization of equations). Theory of reference frames (transformation equations, usual reference frames, variables observed from different reference frames). Synchronous machines theory (voltage and torque equations, transformation to arbitrary reference frame, per unit system). Dynamic equations of synchronous machines (transient torque-angle characteristics, critical clearing time of three phase fault). Synchronous machine operational impedances and time constants, parameter determination by tests. Induction machines theory (voltage and torque equations, transformation of variables to arbitrary reference frame, per unit system, steady state operation). Dynamic performance of asynchronous machines, linearization of synchronous machine and induction machine equations, eigenvalues, eigenvectors, transfer functions. Reduced order synchronous and asynchronous machine models (non-linear and linearized models). Unsymmetrical operation of induction machines, reference frame theory application in unsymmetrical induction machine operation. Asynchronous operation of synchronous machines. Computer simulation of induction machine and synchronous machine operation. Προσομοίωση λειτουργίας μηχανών επαγωγής και σύγχρονων μηχανών στον Η/Υ. Multi-machine Electric Power Systems. Laboratory exercises, computer simulation examples, applications.