Electrical Machines Objective Questions
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In a synchronous motor torque or load angle δ  with increase in load
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In a synchronous generator, if mechanical input is increased with constant excitation, the load angle will
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Which of the following motor has more stability
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The results of a slip test for determining direct axis (X_{d}) and quadrature axis (X_{q}) reactances of a star connected salient pole alternator are given below Phase values: V_{max} = 108 V ; V_{min} = 96 V I_{max} = 12 A ; I_{min} = 10 A Hence the two reactances will be
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In synchronous motor the torque is proportional to
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Synchronous reactance of an alternator represents
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Reactive power generated or delivered significantly depends on
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Slip test is performed to determine
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Universal motors are used in
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When excitation is increased (over excitation), the synchronous generator operates at
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In which of the following motors DC excitation is not required?
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Maximum power developed by a synchronous motor depends on
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Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are 4% and 5% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW?
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Number of slip rings in 3phase synchronous motor will be
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Damper winding is used to
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Stability of a synchronous motor  with the increase in excitation.
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For a 3phase, 4 pole, 50 Hz synchronous motor the frequency, pole number and the frequency are halved. The motor speed will be
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In synchronous generator, inverted V curve is drawn between
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A 3 phase stepper motor has 6 stator poles and 4 rotor poles, then find the step angle?
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Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW?
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The leakage reactance of a 3phase alternator is determined by performing
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Synchronising power of a synchronous motor varies
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Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. How will the machine share, if the load is 600 MW?
Correct!
Wrong!

In synchronous generator V curve is drawn between
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In a synchronous generator with constant steam input supplies power to an infinite bus at a lagging power factor. If the excitation is increased
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In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then
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Which of the following statement is correct, if short circuit ratios is high
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Stepper motor is used in
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Synchronous condensers are used to
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The synchronous reactance( Xs) is the
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