Question :01 Part A
The initial conditions of a d.c. motor are:
K’ = 3:0Vs
V1 = 24:0V
Td = 18Nm
Ra = 2 ohm
For a 50 percent increase in the armature voltage, calculate thepercentage Change in the no-load speed. Assume that the load torqueis unchanged.
Is the increase in speed proportional to increase in armaturevoltage give reson for your answer.
speed.
Part B:
A 50 V, d.c. shunt motor drives a constant-torque load at aspeed of 1200 rpm. The armature and field
resistances are 2 ohm and 100 ohm, respectively. The motor draws aline current of 15 A at the given
load.
(a) Calculate the change in voltage to open the motor to holdingposition(holding position mean \"Yes stopping motor electrically\").And plot the change in
speed with bith the voltages.
(b) Calculate the resistance that should be added to the armaturecircuit to reduce the speed by 50
percent.
(c) Calculate the resistance that must be added to the armaturecircuit to open the motor at the
holding condition.
(d) Plot all the resistance for change in speed.
