A three phase semiconverter feeds the armature of a separately excited dc motor, supplying a nonzero 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 that is

equal to the instantaneous value of the ac phase volatge

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 nonzero 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 that is
A.	equal to the instantaneous value of the ac phase volatge
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 nonzero 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 that is

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