A DC motor is fed with the armature voltage 430 V. At the current load, the speed is 180 rpm and the armature current is 29 A. The armature resistance of the motor is 0.9 Ω and the brush voltage drop is a total of 2.5 V. The shaft torque is 72 Nm and the magnetizing current is 0.87 A at the magnetizing voltage 494.5 V. a) What electrical power does the motor receive? b) what is the mechanical effect that the engine develops? c)determine the efficiency of the motor at this load d) how big will the speed be at half the load torque? (Armature voltage and magnetizing current are unchanged.) Tip: First calculate the motor's k2Fi value - half Half the torque gives half the armature current. e) The speed at idle is approximately (whole number with two decimal places)
A DC motor is fed with the armature voltage 430 V. At the current load, the speed is 180 rpm and the armature current is 29 A. The armature resistance of the motor is 0.9 Ω and the brush voltage drop is a total of 2.5 V. The shaft torque is 72 Nm and the magnetizing current is 0.87 A at the magnetizing voltage 494.5 V.
a) What electrical power does the motor receive?
b) what is the
c)determine the efficiency of the motor at this load
d) how big will the speed be at half the load torque? (Armature voltage and magnetizing current are unchanged.) Tip: First calculate the motor's k2Fi value - half Half the torque gives half the armature current.
e) The speed at idle is approximately (whole number with two decimal places)
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