I need help with solving the question. 7. How transformers are classified according to theirconstruction?8. Explain on the material used for core construction?9.How does change in frequency affect the operationof a given transformer?10. What is the angle by which no-load current will lagthe ideal applied voltage?11. Can the voltage regulation go-ive? If so under whatcondition?12. Distinguish power transformers & distributiontransformers?

7. Transformers are classified based on their construction into two main categories: Core type…

Answered: 7. How transformers are classified…

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.9P

See similar textbooks

Similar questions

For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
In developing per-unit circuits of systems such as the one shown in Figure 3.10. when moving across a transformer, the voltage base is changed in proportion to the transformer voltage ratings. (a) True (b) False
Why is it important to reduce the moisture within a transformer to acceptable levels during transformer installation?
An ideal transformer has no real or reactive power loss. (a) True (b) False
The ideal transformer windings are eliminated from the per-unit equivalent circuit of a transformer. (a) True (b) False
For an ideal 2-winding transformer, the ampere-turns of the primary winding, N1I1 is equal to the ampere-turns of the secondary winding, N2I2 (a) True (b) False
For developing per-unit equivalent circuits of single-phase three-winding transformer, a common Sbase is selected for all three windings and voltage bases are selected in proportion to the rated voltage of the windings (a) True (b) False
Three single-phase, two-winding transformers, each rated 450MVA,20kV/288.7kV, with leakage reactance Xeq=0.10perunit, are connected to form a three-phase bank. The high-voltage windings are connected in Y with a solidly grounded neutral. Draw the per-unit equivalent circuit if the low-voltage windings are connected (a) in with American standard phase shift or (b) in Y with an open neutral. Use the transformer ratings as base quantities. Winding resistances and exciting current are neglected.
1-Why the transformer core made from lamination plates? 2- Why core losses remain almost constant at any load? 3- Why O.C.T. is generally performed on L.V. side (not at H.V. side)?
1.a. For performing dielectric-strength tests on insulating materials, two transformers are connected in aA. parallel combination.B. cascade arrangement.C. polyphase arrangement. 1.b. In large power transformers, the unequal voltage distribution caused by voltage surges in the winding isprevented by the use ofA. static shields.B. series capacitors.c. low-voltage arresters.
A transformer core is laminated in order to ....................................? (A) reduce hysteresis loss and eddy current loss (B) reduce only hysteresis loss (C) reduce copper loss (D) reduce all of the above losses (E) None of the above.
5. Transformer cores are laminated in order to (a) simplify its construction (b) minimise eddy current loss (c) reduce cost (d) reduce hysteresis loss. 6. A transformer having 1000 primary turns is connected to a 250-V a.c. supply. For a secondary voltage of 400 V, the number of secondary turns should be (a) 1600 (b) 250 (c) 400 (d) 1250 7. The primary and secondary induced e.m.fs. E, and E₂ in a two-winding transformer are always (a) equal in magnitude (b) antiphase with each other (c) in-phase with each other (d) determined by load on transformer second- ary. 8. A step-up transformer increases (a) voltage (b) current (c) power (d) frequency. F

SEE MORE QUESTIONS

Recommended textbooks for you

Power System Analysis and Design (MindTap Course …

Electrical Engineering

ISBN:

9781305632134

Author:

J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:

Cengage Learning

Electricity for Refrigeration, Heating, and Air C…

Mechanical Engineering

ISBN:

9781337399128

Author:

Russell E. Smith

Publisher:

Cengage Learning

Power System Analysis and Design (MindTap Course …

Electrical Engineering

ISBN:

9781305632134

Author:

J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:

Cengage Learning

Electricity for Refrigeration, Heating, and Air C…

Mechanical Engineering

ISBN:

9781337399128

Author:

Russell E. Smith

Publisher:

Cengage Learning

SEE MORE TEXTBOOKS