January 6, 2012

ELECTRICAL MACHINES-3 JNTU previous years question papers


ELECTRICAL MACHINES-3 JNTU previous years question papers
 Time: 3 hours Max Marks: 80

Answer any FIVE Questions

All Questions carry equal marks

1. (a) Explain the various winding factors? Explain the effects of each of them.
(b) Determine the slot distribution and the pole phase group sequence for a 45 slot, 6 pole, 3-winding. [6+10]

2. (a) Explain the operation and effect of load power factor on the performance of alternator.
(b) The effective resistance of a 2200 V, 50 Hz, 440 kVA, single phase alternator is 0.5 . On short circuit, a field current of 4 A gives the full load current. The EMF on open circuit for the same field current is 1160 V. Find Synchronous impedance, Synchronous reactance and % regulation of 0.6p.f lagging. [8+8]

3. (a) Explain the various tests to be conducted on an alternator to find the voltage regulation of an alternator.
(b) Explain the effect of ‘Saturation’ on the performance of an alternator. How the effect of saturation can be overcome in calculation. [8+8]

4. (a) Explain all the necessary conditions for successful parallel operation of alternators.
(b) A 2 MVA, 3-, star connected, 4 pole, 750 RPM alternator is operating on 6000 V bus bars, xs is 6 /ph. Find synchronizing power and torque for full load 0.8 power factor lagging. [8+8]

5. A 3- , 30 kW, 400 V, star connected synchronous motor operates on full load at 0.8 pf lagging. The machine has synchronous reactance of 4  & negligible armature resistance. Calculate the new value of current & power factor if the excitation is increased by 50%. [16]

6. The data for no load saturation curve of a 6.6 kV, 1.8 MVA. 3-, 50 Hz, star connected synchronous motor is given below:
V (k V) 3.6 5.9 7.4 7.9 8.4
If Amp 45 91 130 160 210
The effective resistance & synchronous reactance per phase of the motor are 0.35  & 7 respectively. Plot the V curves for this machine when the input is maintained constant at 450 kW. [16]

7. (a) Explain, the speed of single phase Induction motor can be controlled by supply voltage where as them is not possible with 3 - IM, why?
(b) The name plate of single phase IM, 4 pole Induction motor gives the following data:
Output = 410 W, Supply voltage = 230 V, Frequency = 50 Hz,
Input current = 3.2 A, Power factor = 0.7, speed = 1410 RPM.
Calculate:
i. The efficiency of the motor
ii. The slip of the motor when delivering rated output. [8+8]

8. Write short notes on following:
(a) AC series motor
(b) Universal motor
(c) Variable reluctance stepper motor
(d) Permanent magnet stepper motor.

FEEL USEFUL PLEASE GIVE +1

0 comments :

Post a Comment

Get Syllabus in your Mail

Labels

Accenture Admission Notice - 2010 Admission Notification Anna University Anna University Chennai Anna University Question Papers Anna University Trichy Apparel Technology and Management Aptitude Questions Arts and Science Colleges Biomedical Engineering C and CPP Ebooks Calicut University CBSE Question papers Civil Engineering Civil Service Exams Colleges in India Colleges Result Computer Science Engineering Core Jobs CS R2008 CSE CSIR NET EBooks Download ECE EEE EIE Electives Electrical and Electronics Engineering Electronics and communication Electronics and Instrumentation Engineering Engineering Engineering Colleges in Maharashtra Engineering Colleges in TamilNadu Engineering Admissions Engineering Colleges Engineering Colleges in Karnataka Engineering Jobs Engineering Syllabus Entrance Exam Dates Entrance Exam Results Entrance Examination Exam Time Table Experiencer First Year Syllabus Freshers Full Time Jobs Government jobs in india Hardware and Networking Jobs Hotel Management and Catering Technology IGNOU Information Technology INTEVIEW QUESTIONS IT Jobs JNTU Question Papers Jobs in Bangalore Jobs in Chennai Jobs in Coimbatore Jobs in Delhi Jobs in Hyderabad Jobs in India Jobs in Kerala Jobs in Noida Jobs in Tamilnadu Jobs in TATA Karnataka Educations Lab Manuals Mechanical Engineering Medical Colleges Placement Papers Plus 2 Preparation for exams Private Jobs in India Question Papers Question Papers Download Results Announcement Semester 1 Semester 2 Semester 3 Semester 4 Semester 5 Semester 6 Semester 7 Semester 8 Syllabus Syllabus Download Tamil Movie TCS Placement Papers Teaching Jobs TECH MAHINDRA Textile Technology Top colleges University Results UPSC VICEVESVARAYA TECHNOLOGICAL UNIVERSITY waec Walk-in Interview Web Designers

Followers

Archive

Anna university Engineering Syllabus

Earn Money From Online

Government jobs in india

Admission Notification

Total Pageviews

 

Privacy Policy
http://topengineeringcollegesintamilnadu.blogspot.com use third-party advertising companies to serve ads when you visit our website. These companies may use information (not including your name, address, email address, or telephone number) about your visits to this and other websites in order to provide advertisements about goods and services of interest to you. If you would like more information about this practice and to know your choices about not having this information used by these companies, click here.