A three phase semiconverter feeds the armature of a separately excited dc motor, supplying a non-zero torque. For steady state operation, the motor armature current is found to drop to zero at certain instances of time. At such instances, the voltage assumes a value which is

equal to the instantaneous value of the ac phase voltage

equal to the instantaneous value of the motor back emf

A three phase semiconverter feeds the armature of a separately excited

1.	A three phase semiconverter feeds the armature of a separately excited dc motor, supplying a non-zero torque. For steady state operation, the motor armature current is found to drop to zero at certain instances of time. At such instances, the voltage assumes a value which is
A.	equal to the instantaneous value of the ac phase voltage
B.	equal to the instantaneous value of the motor back emf
C.	arbitrary
D.	zero
Answer» C. arbitrary

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A three phase semiconverter feeds the armature of a separately excited dc motor, supplying a non-zero torque. For steady state operation, the motor armature current is found to drop to zero at certain instances of time. At such instances, the voltage assumes a value which is

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