LAB 2 Report circuits 2 PDF

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LAB REPORT NUMBER 2 ...

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Ahmed Gomaa 144171938 Omar Aly 14151932

ECE 2110 Lab (2) Report

Pre-Lab: Problem 1:

Problem 2:

Pre-Lab Calculations: 1. 80:40 V- N1 = 80 V , N2 = 40 V N = 80/40 = 2.

2.

NP

= 280 turns, N s = 140 turns.

N = N P / N s = 2. 3. Using the voltage division equation and ohms law for different values of RL : RL ) R L +100



V L =V .(



I=



PL =V L . I

V R L +100

¿ R L ¿ ohms)

25 40 55 70 85 100 115 130 145 160

I (A)

P(W)

V L (V)

0.64 0.57 0.51 0.46 0.43 0.40 0.37 0.35 0.33 0.31

10.24 13.05 14.50 15.50 15.82 16.00 15.84 15.82 15.61 15.25

16.00 22.90 28.40 32.90 36.80 40.00 42.80 45.20 47.30 49.20

Table 2-1

4.

.

Results: 1. Winding Resistances RP =2.4 ohms

RS

¿ 0.8 ohms

R1

¿ 100 ohms

2. V P (V)

V S (V)

74.70

36.23

I P (A)

PP (W)

0.78

58.26

Table 2-2

3.

R = 40 ohms S = V.I  I = S/V = 80/40 = 2 A V = I.R R = V/I = 40/2 = 20 ohms At power supply V = 80 V ; V S = 16.3 V I 1 = 0.86 A

2 I1 =

I2

I 1 =¿ 1.78 A

N = I 1 / I 2 = 0.483 Power = 19.6 W PINPUT POUTPUT

P ¿ / ¿ ¿

= 10.7 W = 9.4 W

PINPUT

)*100 =

9.4 x 100 10.7

=

87.85%

VS / VP

0.48

R = 25 ohms P = 39 W V = 80 V V P = 40.00V Vs

= 81.90 V

I 1 = 0.05 A I 2 = 0.12 A

N = I 1 /¿

I 2 = 0.05/0.12 = 0.42

V s , load = 26 V

V s , NO load = 37 V V s , NOload −V s ,load

Voltage regulation = PINPUT POUTPUT

V s , load

X 100 =

= 1.8 VA = 1.1 VA

Therefore, efficiency is calculated as; η = ( POUTPUT

/ PINPUT

) x 100 = 61.1 %

37 −27 X100 = 29.1% 37

4.

¿ R L ¿ ohms)

Theo.I (A)

25 40 55 70 85 100 115 130 145 160

0.64 0.57 0.51 0.46 0.43 0.40 0.37 0.35 0.33 0.31

exp . I ( A)

theo . P(

exp . V L (

0.60 0.54 0.46 0.45 0.42 0.39 0.36 0.32 0.31 0.29

W) 10.24 13.05 14.50 15.50 15.82 16.00 15.84 15.82 15.61 15.25

V) 15.77 22.60 25.00 33.20 37.00 40.00 41.80 44.10 47.40 48.10

theo . V L (

V) 16.00 22.90 28.40 32.90 36.80 40.00 42.80 45.20 47.30 49.20

Table 2-1

Results Part 4: 1. Turn ratio = 2 R = (1/n)x R L 

2. Winding loss(VA) =

1 x 20 = 80 ohms 0.52

I2 . R

Where I is the current through the winding, and R the winding resistance.

3. 9% 4.

RL (Ohms) 25 40 55 70 85 100

I (Amps) .63 .58 .53 .48 .46 .39

P (Watts) 9 12 14.7 15.8 16.8 17.3

115 130 145 160

.42 .41 .35 .34

17.8 17.8 17.9 17.0

5.

RL (Ohms) table 2-1 (P VS RL)

Lab notebook: 1. V-ratio at step 2 = 0.486 and I ratio at step 3 = 0.483 values are pretty close to each other but may differ insignificantly due to resistance inaccuracy.

2. There is no primary load therefore there the primary voltage is higher than the second making the transformer a stepdown transformer. 3. I = 0.082 A, I = V.R , I = 74.7/100 = 0.747 4. Power produced is lower than predicted. This makes sense as due to winding resistance and probably small heat loss across the wires part of the power is lost throughout the circuit.

5. Our values were slightly different than the actual values due to either calculation or error produced throughout the circuit due irregularities of the current moving through the circuit....