Ask Electrical & Electronics Expert

1) The tank of a 1250 KVA natural oil cooled transformer has the dimensions of length, width and height as 1.55m x 0.65m x 1.85m respectively. The full load loss is 13.1 kw. Determine the  and ampere conductors per metre as  flux density 1wb/m2 number of tubes for this transformer assuming: W/m2°C due to radiation = 6 and due to convection = 6.5. Improvement in convection due to provision of tubes = 40% temperature rise = 40°C. Length of each tube = 1m and diameter of tubes. Neglect the top and bottom surfaces of the tank as regards cooling.

2) Approximate the stator core dimensions, number of stator slots and number of the stator conductors per slot for a 100 kw, 3300v, 50 Hz, 12 pole star connected slip ring induction motor. Assume average gap density = 0.4 wb/m2 efficiency = 0.9, power factor = 0.9 and winding factor = 0.96 choose main dimensions to give overall design.

3) A 3 phase, 6 pole, 50Hz, 10kw, 220v star connected Induction motor has 54 stator slots each containing 6 conductors. Determine the values of bar and end ring currents. The number of Rotor bars is 64. The machine has an efficiency of 0.86 and a power factor of 0.85. The rotor mmf may be assumed as 85% of stator e.m.f. Also determine the bar and end ring sections if the current density is 5A/mm2

4) a) Deduce the output equation of the salient pole synchronous machine.

b) describe the several factors affecting the choice of short circuit ratio.

5) The field coils of a salient pole alternator are wound with a single layer winding of bare copper strip 30mm deep with separating insulation 0.15mm thick. Determine a suitable winding length, number of turns and thickness of conductor to develop an mmf of 12,000 A with potential difference of 5v per coil and with a loss of 1200 w/m2 1.2m. The resistivity of copper is 0.021?/m and mm2; Conductors per metre = 25,000 A/m of total coil surface. The mean length of turn is.

Electrical & Electronics, Engineering

  • Category:- Electrical & Electronics
  • Reference No.:- M913085

Have any Question?


Related Questions in Electrical & Electronics

Question 1for the ce amplifier in figure 1 given the

Question 1 For the CE amplifier in Figure (1), given the following component parameters: Parameter Value β DC , β AC 150 V BE 0 . 7 V V CC 12 V R C 820 ? R E 1 100 ? R E 2 220 ? R 1 20 k? R 2 5 . 2 k? R L 100 k? C 1 , C ...

Question -i a star-connected three-phase synchronous

Question - (i) A star-connected, three-phase synchronous induction motor takes a current of 10 amps from a 415 volt supply at unity power factor when supplying a steady load. If the synchronous reactance is 5 ohms/phase ...

1 a name the three major groups of contamination and

1. (a) Name the three major groups of contamination and briefly describe their physical characteristics. (b) Where do the above contamination types come from? Give one example of each. 2. Name two processes metrics which ...

Question 1 in the voltage regulator circuit in figure p221

Question 1: In the voltage regulator circuit in Figure P2.21, V 1 = 20 V, V Z = 10 V, R i = 222Ω and P z (max) = 400 mW. (a) Determine I L, I z , and I L , if R L = 380Ω. (b) Determine the value of R L , that will establ ...

Summative assessmentin 2017 sej101 assessment will consist

Summative Assessment In 2017 SEJ101 assessment will consist of nine tasks that will develop a portfolio of your assessed work. Throughout the trimester you will have the opportunity for feedback on all nine tasks before ...

1 a name the three major groups of contamination and

1. (a) Name the three major groups of contamination and briefly describe their physical characteristics. (b) Where do the above contamination types come from? Give one example of each. 2. Name two processes metrics which ...

1 a name the three major groups of contamination and

1. (a) Name the three major groups of contamination and briefly describe their physical characteristics. (b) Where do the above contamination types come from? Give one example of each. 2. Name two processes metrics which ...

Case studythis assignment consists of a written report of

CASE STUDY This assignment consists of a written report of approximately 1000 words and any diagrams in which you are asked to critically compare different process methods used to achieve the same result and show an awar ...

Problem 1 a two-phase servomotor has rated voltage applied

Problem 1: A two-phase servomotor has rated voltage applied to its excitation winding. The torque speed characteristic of the motor with Vc = 220 V, 60 Hz applied to its control phase winding is shown in Fig.1. The momen ...

Electrical engineering questions -q1 two ideal voltage

Electrical Engineering Questions - Q1. Two ideal voltage sources designated as machines 1 and 2 are connected, as shown in the figure below. Given E 1 = 65∠0 o V, E 2 = 65∠30 o V, Z = 3Ω. Determine if Machine 1 is genera ...

  • 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

Why might a bank avoid the use of interest rate swaps even

Why might a bank avoid the use of interest rate swaps, even when the institution is exposed to significant interest rate

Describe the difference between zero coupon bonds and

Describe the difference between zero coupon bonds and coupon bonds. Under what conditions will a coupon bond sell at a p

Compute the present value of an annuity of 880 per year

Compute the present value of an annuity of $ 880 per year for 16 years, given a discount rate of 6 percent per annum. As

Compute the present value of an 1150 payment made in ten

Compute the present value of an $1,150 payment made in ten years when the discount rate is 12 percent. (Do not round int

Compute the present value of an annuity of 699 per year

Compute the present value of an annuity of $ 699 per year for 19 years, given a discount rate of 6 percent per annum. As