The cut-off frequency of disturbance propagation in discrete inertia model of power networks

With the development of power grid interconnection, the disturbance propagation phenomena are more and more apparent which take the form of mechanical waves. Once a disturbance occurs, its propagation might cause cascading events and even large blackouts. However, with the help of advanced communications network in smart grid, new control strategies can be devised by the reveal of disturbance propagation mechanisms. In this paper, disturbance propagation in chained power network is studied from the point of view of network structure and parameters. The discrete inertia model of power systems is built. The increment motion equation of generator is formulated. Then, the wave transfer function is derived which can be used to describe the amplitude and phase variation of disturbance waves. The cut-off frequency of discrete inertia model is proposed to determine the upper limit of disturbance frequency. Furthermore, the computer simulations are carried out and the results demonstrate the validity of the proposed theory.