Consider the motor of Example 16.1.6 in the text.
(a) Determine the armature current and power factor at one-half the rated speed, one-half the rated torque, and rated field current.
(b) Find the torque and field current corresponding to rated armature current, 1.25 times the rated speed, and unity power factor.
Example 16.1.6
A 1500-hp, 6600-V, six-pole, 60-Hz, three-phase, wye-connected, synchronous motor, with a synchronous reactance of 36 Ω, negligible armature resistance, and unity power factor at rated power, is controlled from a variable-frequency source with constant V/f ratio. Determine the armature current, torque angle, and power factor at full-load torque, one-half rated speed, and rated field current. (Neglect friction, wind age, and core loss.)