Ask Question, Ask an Expert


Ask Electrical & Electronics Expert

1) prepare down the energy balance equation of a motor.

2) What is the energy conversion medium in the singly-excited magnetic field system?

3) A100 kVA, 6.6kV/415V, single phase transformer has the effective impedance of (3+8j) _ referred to HV side. Evaluate full load voltage regulation at 0.8 pf lagging and 0.8 leading pf.

4)(a) Describe the working of auto transformer and prove that when transformation ratio approaches unity, amount copper used approaches smaller value.

(b) Emf per turn of single phase, 6.6kV/440V, 50 Hz transformer is approximately 12V. Compute the number of turns in HV and LV windings and net cross sectional area of the core for a maximum flux density of 1.5T.

5)(a) Get the equivalent circuit of a 200/400V, 50Hz,single phase transformer from test data given below:

OC test: 200V,0.7A,70W on LV side
SC test: 15V,10A,85W on HV side

(b) With the help of suitable circuit diagrams, describe any two kinds of three phase transformer connections

6) Determine the all day efficiency of a 500kVA, distribution transformer whose iron loss and full load copper loss are 1.5kW and 6kW respectively. In a day it is loaded as follows:

Duration (Hi)   Output(Po) in kW  Power factor(cosØ2)

     6                      400                               0.8
    10                     300                             0.75
     4                      100                               0.8
     4                         0                                 -

7) Design the circuit diagrams for conducting OC and SC tests on single phase transformer. Also describe how efficiency an d voltage regulation can be estimated by these tests.

8) What do you mean by the sumpner’s test? Design the circuit diagram to conduct this test and describe its principle.

9)(a) Deduce the condition for maximum efficiency in the transformer.

(b) A11000/230 V, 150 KVA, 1-phase, 50 Hz transformer has core loss of 1.4Kw and F.L cu loss of 1.6 Kw. Find out:

(i) kVA load for maximum efficiency and value of maximum efficiency at unity p.f

(ii) Efficiency at half F.L 0.8 pf leading

10) Describe in detail about parallel operation of single phase transformers.

Electrical & Electronics, Engineering

  • Category:- Electrical & Electronics
  • Reference No.:- M911367

Have any Question? 

Related Questions in Electrical & Electronics

A clean 15--efficient module stc 1 m2 in size has its own

A clean, 15-%-efficient module (STC), 1 m 2 in size, has its own 90% efficient inverter. Its NOCT is 44° C and its rated power degrades by 0.5%/° C above the 25° C STC. a. What would its STC rated power be? b. Find the k ...

1 consider three equally spaced sources of strength m

1. Consider three equally spaced sources of strength m placed at (x, y) = ( a, 0),(0, 0), and (a, 0). Sketch the resulting streamline pattern. Are there any stagnation points? 2. Sketch the streamlines and potential line ...

1 assume alice needs to send an e-mail to bob explain how

1. Assume Alice needs to send an e-mail to Bob. Explain how the confidentiality of the e-mail is achieved using S/MIME. 2. When we talk about authentication in SSL, do we mean message authentication or entity authenticat ...

A sinusoid cosomega0t is a bandpass signal with zero

A sinusoid cos(ω0t) is a bandpass signal with zero bandwidth. This implies that the sampling rate that will allow reconstruction of this signal from its samples can be arbitrarily small. Show that this is indeed the case ...

1 find the minimum value of h for which the gate shown

1. Find the minimum value of h for which the gate shown will rotate counterclockwise if the gate cross section is (a) rectangular, 4 ft × 4 ft; (b) triangular, 4 ft at the base × 4 ft high. Neglect bearing friction. 2. A ...

1 what is the total distance around the circumference of a

1. What is the total distance around the circumference of a circle of radius 1 m? What is the total vector distance around the circle? 2. What is the total surface area of a cube of sides 1 m? Assuming the normals to the ...

1 multnomah falls in oregon has sheer drop of 165 m

1. Multnomah Falls in Oregon has sheer drop of 165 m. Estimate the change in water temperature caused by this drop. 2. An ‘‘air cushion'' vehicle is designed to traverse terrain while floating on a cushion of air. Air, s ...

Assignment1 a 1-mhz plane wave is incident from air on an

Assignment 1. A 1-MHz plane wave is incident from air on an infinite copper sheet. If the amplitude of the incident E-field is 100 V/m, find τ, Γ, δ and the magnitude of electric and magnetic fields at a distance of one ...

Derive the 3 x 3 d matrix in equation for a two-dimensional

Derive the 3 X 3 [D] matrix in Equation for a two-dimensional MooneyRivlin material with three material parameters (A 10 , A 01 , and K). Use the perturbed Lagrangian method for near-incompressibility.

Solve problem using the secant method do not use the

Solve Problem using the secant method. Do not use the incremental force method. Discuss about the convergence rate. Problem :- Consider a uniform bar with a constant Young's modulus, E = 100 MPa; cross-sectional area, A ...

  • 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

WalMart Identification of theory and critical discussion

Drawing on the prescribed text and/or relevant academic literature, produce a paper which discusses the nature of group

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