Analysis of Inherent Steady State Stability of Synchronous Machines by the Eigen Values Method （Part 2） -Salient-pole-type Synchronous Machines with Damper Windings-

This paper presents an analysis of the inherent steady state stability of salient-pole-type synchronous machines with damper windings. Eigen values method is used in the same manner as in the preceding paper. Since the general purpose of the damper windings is to stabilize hunting instability, this paper discusses the effects of them on hunting regions. At first, the basic linearized differential equations for a synchronous generator system with damper windings are derived and the characteristics of the eigen values are considered. It is shown that the steady state stability is determined by the three dominant eigen values in the same way as in a damper-less system. Next, calculations of the steady state stable regions for the various circuit conditions are carried out, and the effects of circuit parameters on the stable region are discussed. In particular, the effects of damper circuit parameters on the hunting region are discussed in detail