Analogue computer simulation and phase space study of a synchronous machine with flux-decay effect transient stability

The paper describes how a general-purpose electronic analogue computer and the phase space method may be used to solve the transient stability problem of a synchronous machine connected to an infinite bus. In the machine analysis emphasis is placed on the effects of the flux-decay, damping power and saliency during transient disturbances. The swing equation of the machine is a third-order nonlinear differential equation. In the paper the phase plane method is extended to this third-order nonlinear swing equation and the system trajectories, the boundary surface of asymptotic stability and the critical clearing time of the system have been obtained by the use of an analogue computer. A numerical example is given.