ELEC 242 Lab
Interlude
DC Motor Dynamics
Consider a DC motor with armature resistance
, torque constant
, and back emf constant
being driven by a source with output resistance
:
J
represents the combined moment of inertia of the motor
armature and the load.
Then we have
.
From the coupling equations we have
and
.
Defining
, Ohm's law gives
.
But we also have
.
Combining these we get
or