A DC machine (6 kW, 120 V, 1200 rpm) has the following magnetization characteristics at 1200 rpm:
IF (A) Ea (V)
0.1 5
0.2 20
0.3 40
0.4 60
0.5 79
0.6 93
0.8 102
1.0 114
1.2 120
1.4 125
The machine parameters are Ra = 0.2 Ω, Rfw = 100 Ω. The machine is driven at 1200 rpm and is separately excited. The field current is adjusted at If = 0.8 A. A load resistance RL = 2 Ω is connected to the armature terminals. Neglect armature reaction effect.
Determine the quantity KaΦ for the machine.
Determine Ea and Ia.
(c) Determine torque T and load power PL.