There are presently four fully developed machine models available in EMTDC: A Synchronous Machine, a Squirrel Cage Induction Machine, a Wound-Rotor Induction Machine and a DC Machine. These models are all programmed in state variable form, using generalized machine theory.
The machine subroutines interface with EMTDC as a compensated current source and special terminating impedance, as well as to other subroutines through mechanical and/or field parameters.
The parameters of the various machines behave differently, so therefore separate subroutines are used. For instance, the Synchronous Machine possesses different parameters on each axis, with only direct-axis mutual saturation of any significance. On the other hand, an induction motor uses the same equivalent circuit on both axes, and experiences both mutual and the leakage reactance saturation.
Other models described in this chapter, which can be used interface to the machine models, are: