Propagation speed of disturbance in large-scale power system

A large-scale power system can be modeled as discrete generators connected with continuum transmission line. In this paper, a method of estimating the propagation speed of electromechanical disturbance in large-scale power system has been presented. Traditionally, the existing analysis of electromechanical disturbance propagation characteristics has focused on the continuum power system. If the same method is used for the large-scale power system, the feature of distributed transmission line and time-delay between two machines would be neglected. This is restrictive because, for large-scale power system, the time-delay of transmission line can be used for coordinating online wide-area control and propection. In this paper, it is firstly find a distributed large-scale power system model, and changes in the electrical power caused by disturbances. Then, via the distributed transmission line and incremental model, a calculating function of electromechanical disturbance propagation speed for distributed large-scale power system is derived. With simulating a 3-machine-6-bus system, the results verify that the electromechanical disturbance propagation has interesting properties.