A Method of Power System Simulation Taking Armature Transient of Synchronous Machines into Consideration

Abstract

This paper presents a new method of simulating transient responses of multi-machine power system following a large disturbance. The conventional model used in the simulation is composed mostly of synchronous machine models, in which the armature transients are neglected, and steady state transmission system equations. This is because it is very complicated to treat the transmission system and the armature circuits of synchronous machines as differential equations. Naturally the model can not evaluate the effects of these transients neglected. The new method proposed uses the new synchronous machine model and the steady state transmission system model. The former is obtained by modifying slightly the conventional armature transient neglected model. Thus the resultant simulation model has almost the same structure as the conventional one. However it can evaluate approximately the effects of armature transients on the dynamical behaviour of the synchronous machines. For example, it can e valuate easily the angular back swing following a three phase short-circuit fault. In addition, the new method can also estimate the maximum values of developed torque, induced voltage and armature current of synchronous machines at the moment when the disturbance occurred and it was cleared.