Introduction to
Engineering and Technology
CCRI ENGR-1020
Spring 2007
Team Members
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Starting Wind Turbine
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Improved Wind Turbine
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Turbine Open Circuit Voltage Test Results
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Detail
description |
Detail Photo |
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Our first model
turbine was the Picoturbine, and looked just like everyone else’s… |
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Our improved
design was noted as the top performer producing a total of 44 Volts of AC
current. Shown here are 2 of the
8 coils used in the design. They
are mounted with zip-ties to a rotating disk (rotor), and wired to 2 brass
bands shown below. (This is
called a commutator.) The disk
rotates between two stationary plates each with six magnets, which alternate
poles. The magnets are placed
with opposite poles across from each other to allow the coils to cut the
magnetic lines of flux at a more perpendicular angle. |
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The commutator
is made from brass bands that are glued in place with a screw where the ends
overlap. They are fixed to a piece of a wooden dowel about 1 ¼ inches in
diameter. The dowel and rotor
are mounted with setscrews onto a 5/8 inch diameter aluminum shaft
that is held in place by stationary supports with ball bearings to allow for
rotation. The electricity
created travels through pieces of spring steel mounted onto the base. |
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At the end of
our shaft is our propeller, which is also made of aluminum. The blades are wide towards the
center and narrower at the tip to allow for maximum efficiency. They also curve sharply at the ends
to reduce cut in speed. |
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Although there
were expenses lost due to a revision of our design, the cost of the turbine was
low.
PICO-Turbine
Starter Kits –x2 $35.00
House Fan -x1 $14.00
Aluminum Shaft -x1 $
1. 47
Working with a
team of qualified, friendly people… …priceless.
Total: $85.47
To test the
turbine, we placed it in front of a high-powered fan approximately 2 feet
away. The fan was controlled by a
rheostat that allowed us to increase and decrease wind speeds as
necessary. We tested at speeds
ranging from 1-16 miles per hour with 3 different load resistances. The first resistance was zero, the
second was 100 ohms, and the final load resistance was 200 ohms. We recorded RPM, frequency, and voltage
output for each resistance and used the information gathered for our graph of
the turbine’s power curve.
Turbine Open
Circuit Voltage Test Results
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Improved Turbine Test Results |
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Open Resistance |
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Wind Speed |
Tach (RPM) |
Voltage (v) |
Freq. (Hz) |
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Cut-In |
6.7 |
261 |
15.28 |
12.87 |
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7.6 |
334 |
18.54 |
15.69 |
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9.4 |
393 |
21.15 |
17.8 |
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10.3 |
418 |
24.31 |
20.77 |
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11.1 |
431 |
25.62 |
21.8 |
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12.4 |
459 |
27.29 |
23.17 |
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13 |
585 |
34.4 |
29.25 |
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14.3 |
606 |
34.4 |
29.35 |
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15.6 |
724 |
42.94 |
37.28 |
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Ohm Resistance = |
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200 |
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Wind Speed |
Tach (RPM) |
Voltage (v) |
Freq. (Hz) |
Total Power |
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6.7 |
0 |
0 |
0 |
0 |
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7.6 |
49 |
1.46 |
2.52 |
0.018 |
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9.4 |
55 |
1.55 |
2.7 |
0.020 |
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10.3 |
88 |
2.96 |
8.33 |
0.072 |
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11.1 |
142 |
5.59 |
2.63 |
0.258 |
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12.4 |
190 |
7.32 |
3.57 |
0.442 |
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13 |
365 |
13.15 |
6.15 |
1.426 |
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14.3 |
397 |
14.01 |
6.61 |
1.618 |
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15.6 |
496 |
17.33 |
11.03 |
2.476 |
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Ohm Resistance = |
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100 |
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Wind Speed |
Tach (RPM) |
Voltage (v) |
Freq. (Hz) |
Total Power |
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6.7 |
0 |
0 |
0 |
0 |
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7.6 |
57 |
0.7707 |
0 |
0.014 |
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9.4 |
30 |
0.6025 |
0 |
0.008 |
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10.3 |
59 |
1.596 |
11.96 |
0.059 |
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11.1 |
90 |
2.19 |
19.64 |
0.110 |
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12.4 |
100 |
2.29 |
11.92 |
0.120 |
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13 |
247 |
6.02 |
3.8 |
0.833 |
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14.3 |
285 |
7.59 |
7.17 |
1.324 |
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15.6 |
360 |
9.295 |
5.91 |
1.985 |
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RG = |
129.76 |
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PT= (VL2/RL)(1+RG/RL) |
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Power Curve |
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N - number of loops of wire |
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2190 |
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Equations |
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A - area enclosed by loop (m2) |
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0.001764 |
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1 |
Z=TRPM/60 |
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P - number of magnetic poles |
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6 |