Electrical Machines Questions and Answers – Synchronous Machines
Power Angle Characteristics of Synchronous Machines
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For the effective electromechanical energy conversion in the device, the developed torque depends upon
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Wrong!

A synchronous machine which is synchronized with an infinite bus. If it is desired to obtain a condition when the machine delivers the real power to the IBB without changing the field excitation, then
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Wrong!

A synchronous generator is running over excited with a Ef=1.40pu. This machine, with a synchronous reactance of 1.2pu, is delivering a synchronous power of 0.5pu to the bus. If the primemover torque is increased by 1%, by how much will the reactive power, Q change?
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Choose the correct power angle characteristics for the synchronous motor and generator
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A synchronous generator is operating with a Ef=1.40pu. This machine having Xs of 1.2pu, is delivering a synchronous power of 0.5pu to the bus. If the primemover torque is increased by 1%, by how much will the synchronous power P change?
Correct!
Wrong!

The phasor addition of stator and rotor mmfs in a cylindrical rotor synchronous machine, is possible because
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For a 3 phase 400V alternator supplying a load of 0.8 pf lagging at an armature current of 1.1pu. The power delivered to load is
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A 3 phase 400V salient pole alternator is running at noload. Suddenly the excitation is removed then the net power in the machine is proportional to
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The powerangle characteristic for a three phase salient pole alternator is most correctly shown by
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For a 3 phase 400V alternator having 0.5pu of synchronous reactance and its excitation voltage of 1.2pu and Vt of 1pu. Then the power delivered to the infinite bus is
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In a synchronous machine, hunting is predominantly damped by
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A 3 phase 400V cylindrical rotor is running at 1500rpm. Suddenly the field excitation zero. Then the net reluctance power is
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Maximum power in cylinder rotor alternator occurs at load angle of
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A cylindrical rotor alternator can also run as reluctance motor
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If the synchronous machine is connected to an infinite bus of constant voltage Vt, through a transformed, a transmission line of reactance â€˜Xâ€™. then power for a cylindrical machine is
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