Question

A 75-kW, 440-V, 0.8-PF-leading Y-connected synchronous generator has an armature resistance of 0.22 Ω and a synchronous reactance of 3.0 Ω. Its efficiency at full load is 89% (1 Hp=746 watt).

(a) What is the line current of the generator at rated conditions?

(b) What is the internal generated voltage EA of this motor at rated conditions?

Answer #1

[question in beginning states generator but part b says motor. solved it for genrator.]

The 400 V, 50 kVA, 0.8 power factor leading delta connected
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neglected. It is supplying a 12-kW load with initial power factor
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core losses are 1.5 kW. Determine
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and excitation voltage.
(b) If the flux of the motor is increased by 20 percent
determine the excitation voltage; armature current; and...

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(ia) (180)
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(ia) 230 Ampere and power factor of 0.6 lagging,
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2. Find the generated voltage, EA (10p)
3. Find the torque and the maximum inducible torque in current
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Question : Draw a Capability curves!

A three phase Y connected synchronous motor has negligible
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c. What is its armature current?

A two-pole Y-connected generator rated at 13.8 kV, 20 MVA, 0.8
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negligible armature resistance per phase. The generator is operated
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(i) What is the torque angle of the generator at rated
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