Question

A 208 V, star-connected, 3-phase synchronous motor has a synchronous reactance of 4 ohms/phase and negligible...

  1. A 208 V, star-connected, 3-phase synchronous motor has a synchronous reactance of 4 ohms/phase and negligible armature winding resistance. At a certain load, the motor takes 7.2 kW at 0.8 pf lagging. If the power developed by the motor remains the same while the excitation voltage is increased by 50% by raising the field excitation, determine (a) the new armature current and (b) the new power factor.
0 0
Add a comment Improve this question Transcribed image text
Know the answer?
Add Answer to:
A 208 V, star-connected, 3-phase synchronous motor has a synchronous reactance of 4 ohms/phase and negligible...
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for? Ask your own homework help question. Our experts will answer your question WITHIN MINUTES for Free.
Similar Homework Help Questions
  • Question 4 (10 marks) A) A 10-kVA, 415-V, three phase, Y -connected synchronous generator has a...

    Question 4 (10 marks) A) A 10-kVA, 415-V, three phase, Y -connected synchronous generator has a winding resistance of 0.3 Q and a synchronous reactance of 0.6 on a per phase basis. Determine its voltage regulation at full load when the power factor is (a) 75% lagging and (b) 75% leading. B) (10 marks) A 220-V, Y-connected, three-phase, synchronous motor has a synchronous reactance of 4 O/phase and negligible armature winding resistance. At a certain load the motor takes 7.5...

  • Be detailed please A three-phase y-connected 2300 V, 60 Hz round-rotor synchronous motor has a synchronous...

    Be detailed please A three-phase y-connected 2300 V, 60 Hz round-rotor synchronous motor has a synchronous reactance of 2 ohms/ phase and negligible armature resistance. 2. If the motor takes a line current of 350 A operating at a leading pf of 0.8. calculate the armature voltage and the power angle. If the motor is operating on load with a load angle of-20%, and the excitation is adjusted so that the armature voltage is equal in magnitude to the terminal...

  • 1. A three-phase, 5 kVA, 208 V, four-pole, 60 Hz, wye-connected synchronous machine has...

    A three-phase, 5 kVA, 208 V, four-pole, 60 Hz, wye-connected synchronous machine has negligible stator winding resistance and a synchronous reactance of 8 Wper phase. It is operated in parallel with a three-phase, 208 V, 60 Hz power supply.Determine the excitation voltage and the power angle when the machine is delivering rated kVA at 0.8 pf lagging. Draw the phasor diagram

  • (Question 1): (4pts) A three-phase, 2300-V, 60-Hz, 10-pole, A-connected cylindrical rotor synchronous motor has a synchronous...

    (Question 1): (4pts) A three-phase, 2300-V, 60-Hz, 10-pole, A-connected cylindrical rotor synchronous motor has a synchronous reactance of 4.0 82/phase. The armature resistance may be neglected. It is connected to 2300-V source and drives a system with its excitation set to give a PF of 0.9-leading when the power is 500-kW. (a) Sketch the phasor diagram of this motor. (b) Calculate the armature current. (c) Calculate the excitation voltage and torque angle. (d) If the load torque is increased by...

  • A three-phase synchronous motor has a synchronous reactance of 7 ohm/phase. And the armature resistance is...

    A three-phase synchronous motor has a synchronous reactance of 7 ohm/phase. And the armature resistance is negligible. The input power is 1000 kW, and the excitation voltage is 4500 volts rms. If the terminal voltage of the motor is 4060 volts rms. Then find: a) the power angle ; b) the armature current ; c) the power factor

  • A 3-phase, 7 kVA, 400 V, 2-pole, star-connected synchronous machine has negligible armature resis...

    A 3-phase, 7 kVA, 400 V, 2-pole, star-connected synchronous machine has negligible armature resistance and Xs-60/phase at rated terminal voltage The machine first runs as a generator in parallel with 3-phase, 400 V, 50 Hz power supply 111 Determine the generated voltage and torque angle of the machine operating as a generator, delivering rated kVA at 0 9 pf lagging Draw and label the corresponding phasor diagram for this condition 1 12 If the field excitation is increased by 18%...

  • A 3-phase, 6,600 V, 6,000 HP, star-connected synchronous motor is to be operated under rated conditions...

    A 3-phase, 6,600 V, 6,000 HP, star-connected synchronous motor is to be operated under rated conditions with full-load and a leading power factor of 0.50. The rotational losses under this conditions are 130 kW and may be taken as constant. The effective resistance and reactance are 0.085 and 2.90 ohms respectively. What is the value of the excitation voltage under this condition?

  • 1- A 25-kVA, 3-phase, wye-connected, 400-V alternator has a synchronous reactance of 1.6 ohms per phase....

    1- A 25-kVA, 3-phase, wye-connected, 400-V alternator has a synchronous reactance of 1.6 ohms per phase. The alternator is to have zero voltage regulation at half-load. Neglecting the armature resistance, find the operating power factor and the developed power 2. A 500-kVA, 3600-V, 3-phase, 60-Hz alternator has an effective armature resistance per phase of 0.40 ohm Mechanical and iron losses is 10 kW, field current at full load unity power factor is 70 A. The exciter voltage is constant at...

  • A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.5Q/phase and a...

    A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.5Q/phase and a synchronous reactance of 5Q/phase. The generator is supplying its rated power at its rated voltage and at a power factor lagging. The rotational loss is 2 kW. Calculate: (a) the power developed, (b) the power angle, (c) the voltage regulation, and (d) the shaft torque. A 1500-kVA, 6.6 kV, 50 Hz, 6-pole, three-phase, star-connected synchronous generator has a resistance 0.50/phase and a synchronous...

  • 2) A 480 V, 60 Hz, 400 hp 0.8 PF-lagging eight-pole A-connected synchronous motor has a...

    2) A 480 V, 60 Hz, 400 hp 0.8 PF-lagging eight-pole A-connected synchronous motor has a synchronous reactance of 0.6 and negligible armature resistance. Ignore the mechanical and core losses. The magnitude of the internal machine voltage is 480 V when the field current is 4 A. Assume magnetic linearity. Initially, the motor operates at the rated conditions. a) Find the speed of this motor. b) Find the armature and field currents. c) What is the developed torque? What is...

ADVERTISEMENT
Free Homework Help App
Download From Google Play
Scan Your Homework
to Get Instant Free Answers
Need Online Homework Help?
Ask a Question
Get Answers For Free
Most questions answered within 3 hours.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT