Ask Question, Ask an Expert

+1-415-315-9853

info@mywordsolution.com

Ask Electrical & Electronics Expert

problem 1: Briefly describe why an electronic soft starter is becoming much popular to limit the starting current of an induction motor.

problem 2: State ONE benefit and ONE drawback of using a soft starter with a three phase delta joined squirrel cage induction motor.

problem 3: A 440 V, 3 phases, 50 Hz, 4 – pole, Y – connected induction motor has a full load speed of 1425 rpm. The rotor has an impedance of (0.4+j4) ohms and rotor or stator turns ratio of 0.8. Compute (a) full load torque (b) rotor current and full load rotor Cu loss (c) power output if wind age and frictional losses amount to 500 W, (d) maximum torque and the speed at which it occurs (e) starting current (f) starting torque.

problem 4: State TWO benefits of using a synchronous induction motor rather than an asynchronous induction motor.

problem 5: Regarding skewing of motor bars in a squirrel-cage induction motor, (or SCIM) which statement is false?

a) It prevents cogging.
b) It raises starting torque.
c) It produces more uniform torque.
d) It reduces motor 'hum' throughout its operation.

problem 6: A three-phase, two-pole, 50-Hz induction motor is observed to be operating at a speed of 3502 revolutions per minutes with an input power of 15.7 kW and a terminal current of 22.6 A. The stator winding resistance is 0.20 ohms/phase.

Compute the I2 R power dissipated in the rotor.

problem 7: The magnetizing current drawn by transformers and induction motors are the cause of their …….power factor.

problem 8: The result of increasing the length of air-gap in an induction motor will be to rise the…………

problem 9: In a 3-phase induction motor, the relative speed of the stator flux with respect to ….. is zero.

problem 10: The eight-pole wound rotor induction motor operating on 60 Hz supply is driven at 1800 r.p.m. through a prime mover in the opposite direction of revolving magnetic field. The frequency of the rotor current is…….

problem 11: A 3-phase, 4-pole, 50-Hz induction motor runs at a speed of 1440 r.p.m. The rotating field produced by the rotor rotates at a speed of……r.p.m. with respect to rotor.

problem 12: In a 3-φ induction motor, the rotor field rotates at synchronous speed with respect to………

problem 13: Irrespective of the supply frequency, the torque developed through a SCIM is same whenever ………is the same.

problem 14: The number of stator poles generated in the rotating magnetic field of a 3-φ induction motor having 3 slots per pole per phase is…..

problem 15: A 6-pole, 50-Hz, 3-φ induction motor is running at 950 rpm and consists of rotor Cu loss of 5 kW. Its rotor input is…..kW.

problem 16: Fill up the blanks.

When load is placed on a 3-phase induction motor, its

(a) Speed…  
(b) Slip....
(c) Rotor induced emf….  
(d) Rotor current…..  
(e) Rotor torque….  
(f) Rotor continues to rotate at that value of slip at which developed torque equals..…….torque.

Electrical & Electronics, Engineering

  • Category:- Electrical & Electronics
  • Reference No.:- M9552

Have any Question? 


Related Questions in Electrical & Electronics

1 in an impulse invariance design show that if has is a

1. In an impulse invariance design, show that if Ha(s) is a transfer function of a stable system, the corresponding H[z] is also a transfer function of a stable system. 2. First-order backward differences provide the tra ...

Determine the maximum film velocity in problemproblem

Determine the maximum film velocity in Problem. Problem Aviscous film drains uniformly down the side of a vertical rod of radius R. At some distance down the rod, the film approaches a terminal or fully developed flow su ...

1 implement the d latch to include an enable line using

1. Implement the D latch to include an enable line using Logisim. The enable line will be used to control when the D latch is set, so it is only set if the clock and enable line are high. 2. Implement the D latch to incl ...

1 distinguish between centralized and decentralized p2p

1. Distinguish between centralized and decentralized P2P networks. 2. What are the advantages and disadvantages of a centralized P2P network? 3. What are the advantages and disadvantages of a decentralized P2P network? 4 ...

1 distinguish message authentication and entity

1. Distinguish message authentication and entity authentication. 2. Alice signs the message she sends to Bob to prove that she is the sender of the message. Which of the following keys does Alice need to use? a. Alice's ...

1 what is the significance of a b times c 02 is it

1. What is the significance of A · B × C = 0? 2. Is it necessary for the reference vectors a 1 , a 2 , and a 3 to be an orthogonal set? 3. State whether a 1 , a 2 , anda3 directed westward, northward, and downward, respe ...

Assume you want to write a program to simulate the

Assume you want to write a program to simulate the permutation boxes in Figure 31.8 in the text. a. Show how you represent each box as a table. b. Show the inversion of each box as a table.

A square plane-strain element is deformed as shown in the

A square plane-strain element is deformed as shown in the figure. The relationship between deformed and undeformed coordinates is given as x 1 = X 1 - αX 1 X 2 , x 2 = X 2 , x 3 = X 3 Compare the engineering strain and L ...

Research paperwrite a research essay about zigbee for

Research Paper Write a research essay about zigbee for electrical class. The research paper should include four pages and three references.

Answer the following questionsa how many output lines would

Answer the following questions. a. How many output lines would a 4 input decoder have? b. How many output lines would a 5 input decoder have? c. For an N-to-X decoder, specify X as a function of N (e.g. specify the numbe ...

  • 4,153,160 Questions Asked
  • 13,132 Experts
  • 2,558,936 Questions Answered

Ask Experts for help!!

Looking for Assignment Help?

Start excelling in your Courses, Get help with Assignment

Write us your full requirement for evaluation and you will receive response within 20 minutes turnaround time.

Ask Now Help with Problems, Get a Best Answer

Section onea in an atwood machine suppose two objects of

SECTION ONE (a) In an Atwood Machine, suppose two objects of unequal mass are hung vertically over a frictionless

Part 1you work in hr for a company that operates a factory

Part 1: You work in HR for a company that operates a factory manufacturing fiberglass. There are several hundred empl

Details on advanced accounting paperthis paper is intended

DETAILS ON ADVANCED ACCOUNTING PAPER This paper is intended for students to apply the theoretical knowledge around ac

Create a provider database and related reports and queries

Create a provider database and related reports and queries to capture contact information for potential PC component pro

Describe what you learned about the impact of economic

Describe what you learned about the impact of economic, social, and demographic trends affecting the US labor environmen