# Tachometer & Anemometer controlled DC Motor

Discussion in 'The Projects Forum' started by Kesdjan, Mar 6, 2009.

1. ### Kesdjan Thread Starter New Member

Mar 6, 2009
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I am trying to design a circuit that controls a DC Motor which drives the furl (turning out of wind) of a wind turbine.

The circuit is to take two inputs from a Tachometer (measure RPM of turbine blades) and an Anemometer (measures wind speed).

Then based on the logical combinations of these two inputs it causes the Motor to turn a gear either: -

1. 30 degrees CW
2. 30 degrees CCW
3. 15 degrees CCW

Can someone point me in the right direction?

Thanks

2. ### Bernard AAC Fanatic!

Aug 7, 2008
4,949
551
Just a starting point: Assuming input signals are well filtered DC voltages; use two sets of comparators, one set for strong wind, second for verry strong wind. With moderate wind exceeding WS limit, but load holding RPM in limit =no change. If both strong wind limits exceeded , motor is started, direction controlled by wind vane switch, rotation untill 15 deg. limit sw reached, 15 deg FF reset.Verry strong wind activates 30 deg. comp. 15 deg signal inhibited, motor rotates to 30 deg. limit. Something to throw darts at at least.

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3. ### Kesdjan Thread Starter New Member

Mar 6, 2009
2
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Thanks for the replies, I have no problems working out the logic, or the combinations of conditions to produce a particular output, what i am struggling with is converting that into electronics!

So I need something to take in the voltage from the tachometer, and respond to three different possibilities:
1. RPM is greater than 240
2. RPM is between 200 and 240
3. RPM is less than 200

Then combining these with two conditions for the wind speed v:
1. v is greater than 20
2. v is less than 20

So for example, motor is normally off, whem RPM exceeds 240, motor is activated and furls +30 degrees, RPM is then checked, if still more than 240, furls further +30 degrees. If between 200 and 240, wind speed is checked, if that is more than 20, nothing happens, if less than 20, motor furls -15 degress.

You get the picture, but

1.how do you translate these ifs and ands into a circuit? and
2.how do you get three different repsponses to one measurement (RPM), I understand if it is on/off it is simple, but the "between" complicates things for me!

Thanks
Sary

4. ### Bernard AAC Fanatic!

Aug 7, 2008
4,949
551
New information: Now allowed furling 0-90 deg.? Need one more input, a voltage representing wind direction bearing, say 0-5V for 0-90 deg. how about some voltages from tach. & anemom.