Dynamic mechanism on electromechanical wave propagation in power systems

In order to grasp the influence mechanism of generator internal reactance to electromechanical disturbance propagation, based on continuum modeling for power systems, partial differential equation describing electromechanical wave propagation after generator internal reactance ignored is presented. Using the contour integration of inverse Laplace transform by a novel constructed function, the analytical expressions of electromechanical wave propagation under the excitation of impulse- and step-function are derived. Next, the correctness is validated by a discrete uniform chain power system model using the simulation technique. Furthermore, influence of generator internal reactance to electromechanical wave propagation is analyzed and compared between a uniform chain-and real-power system, respectively. What´s more, the key bus and key bus group are defined, and their importance to electromechanical wave propagation is also studied. The results show that electromechanical wave still propagates within a power system in the form of traveling wave after the effect of internal reactance is considered, but takes on nonlinear dispersion characteristics, and the waveform is also distorted.