Briefly explain the following:1- The starting torque for a three-phase squirrel cage induction motor is 1.5 to 2 times thefull-load torque, and the starting current is 5 to 6 times the full-load current?2- The frequencies of the rotor currents at starting and at full-load are different?3- The alternators cannot be connected to a live busbar when they are at standstill?4- The three phase induction machines often called "rotating transformer"?5- The three phase induction motor can rotates in reverse direction if two lines of thesupply voltage are exchanged?6- The magnetizing and demagnetizing effects of the armature current in the synchronousmotor?

Solution 1) Why Higher Starting Torque?The motor needs extra torque to overcome inertia when it…

Answered: Briefly explain the following: 1- The…

Delmar's Standard Textbook Of Electricity

7th Edition

ISBN:9781337900348

Author:Stephen L. Herman

Publisher:Stephen L. Herman

Chapter32: Three-phase Motors

Section: Chapter Questions

Problem 6RQ: Name three factors that determine the torque produced by an induction motor.

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Similar questions

6- Which of the following supply is given to the rotor winding of 3-Phase Induction Motor: a) DC Supply b) AC Supply c) No Supply d) Pulsating Supply 7- 3-Phase Induction Motor will have Starting Torque and Starting Current a) High, High b) Low, Low. c) High, Low d) Low, High 8- Which of the following method is used for controlling the speed of an induction motor: a) Changing number of stator poles b) Supply voltage control c) Frequency control d) All the options are correct 9- Which of the following method cannot be used for starting of 3-Phase Squirrel Induction Motor: a) Star-Delta Starting b) Line resistor startling c) transformer Starter d) Rotor Resistance Starting 10- The rotor of a stepper motor has no: a) windings b) commutator c) brushes d) all of the above
A) Although the magnetic field for each phase of a 3-phase induction motor is merely switching back and forth between north and south poles, the resultant magnetic influence from all phases sets up a rotating magnetic field to cut the rotor conductors. a) true b) false B) In a two-pole stator winding of a 3-phase motor, how many revolutions does the rotating tr) magnetic field make in one cycle of the electrical current? a) one b) 60 c) 3600 d) none of the above
Which of the following statements about three-phase induction motor is false (A) The speed of rotation of the magnetic field is called the synchronous speed. (B) A three-phase supply connected to the rator produces a rotation magnetic field. (C)The rotating magnetic field has a constant speed and constant magnitude. (D) It is essentially a constant speed type machine.
1. The operation of Commutator in DC Motor is * O a) to convert dc to ac O b) to convert ac to dc O c) to convert fixed dc to variable dc O reverse the current direction in the rotating windings each half turn
Please solve this problem step by step and illustrate your answer properly. Write your answer in a piece of paper please. Box the final answer.
At standstill condition , the slip of induction motor is 1. Select one: O True O False
A) Although the magnetic field for each phase of a 3-phase induction motor is merely switching back and forth between north and south poles, the resultant magnetic influence from all phases sets up a rotating magnetic field to cut the rotor conductors. a) true b) false B) In a two-pole stator winding of a 3-phase motor, how many revolutions does the rotating magnetic field make in one cycle of the electrical current? a) one b) 60 c) 3600 d) none of the above 3.
A 5-hp four-pole 60-cycle three-phase induction motor with a wound rotor draws 4,590 watts from the line. What is the speed of this motor when delivering 4.95 hp, if the core loss is 250 watts, the stator copper loss is 390 watts, and the friction and windage loss is 70 watts?
Armature reaction in an alternator primarily affects: A: rotor speed B: terminal voltage per phase C: frequency of armature current D: generated voltage per phase
T-a. The direction of rotation of a single-phase split-phase motor can be change by........ a) reversing the connection of the start winding b) reversing the connection of the run winding c) reversing the connection of the start and run winding at the same time d) "a" or "b", not "c" T-b. Single-phase split-phase motors using an electrolytic capacitor in the start winding circuit should not be cycled more than about__________ time per hour. a) 8 b) 12 c) 24 d) none of the above T-c. When replacing the capacitor in a capacitor-start induction-run motor, one must be sure to replace the bad capacitor with__________ . a) a smaller one b) one of the same size c) a larger one d) none of the above
3-Phase 50Hz 6 pole induction motor has rotor resistance of 0.1 ohm and reactance of 0.92. ignore voltage drop in stator and assume thee rotor resistance is constant. Full load slip is 3%, then find Tmax /Tfl
True or fulse

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