The armature is the rotating or stationary component in an electric machine where voltage is induced or current flows.
In an ideal condition, the internal resistance of the armature winding should be zero to ensure:
- No voltage drop within the armature itself,
- Maximum terminal voltage is delivered to the load, and
- No internal power losses due to resistive heating ($I^2R$ losses).
If there is any resistance in the armature winding, part of the generated voltage is lost internally, reducing the efficiency and performance of the machine.
Thus, zero internal resistance is ideal for perfect energy conversion.