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In: Electrical Engineering

Problem 5) A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance...

Problem 5)
A long shunt 600 V, 1200-rpm DC motor has a series field winding resistance of 0.05 Ω, a shunt field winding resistance of 200 Ω, and an armature resistance of 0.1 Ω. The machine is connected to 600 V DC source. The rotational loss is 3.2 kW. If the machine draws a 100 A from the supply, calculate
a. Back EMF
b. Determine the machine’s converted power (or developed power) and its efficiency.
c. Determine the speed regulation if the machine draws 165 A at full load.
  

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