The constant-speed magnetization curve for a 25-kW, 250-V dcmachine at a speed of 1200 r/min is shown in figure below. Thismachine is separately excited and has an armature resistance of0.14 Ω. This machine is to be operated as a dc generator whiledriven from a synchronous motor at constant speed. a. What is therated armature current of this machine? b. With the generator speedheld at 1200 r/min and if the armature current is limited to itsrated value, calculate the maximum power output of the generatorand the corresponding armature voltage for constant field currentsof (i) 1.0 A, (ii) 2.0 A and (iii) 2.5 A. c. Repeat part (b) if thespeed of the synchronous generator is reduced to 900 r/min.
