automatic wind turbine [advice]

Hello,

I am a student and i want to create an automatic wind turbine. I am totally beginner and i just know my physics lessons!
I need an advice for my project. I want to turn my wind turbine in front of the wind automatically. To do that i chose 4 steps.

  1. I turn the wind turbine from 0° to 360° and with the potentiometer i measure the angle of the position of the wind turbine

2)At the same time, i measure the voltage produce by the wind turbine.

  1. I enter those informations in the arduino card

  2. The arduino card calculated a fonction between produced voltage and postion of the wind turbine and the output of the arduino card is a motor which turn the wind turbine to the angle where the produced voltage is maximal

I need you to tell me if my project is feasible (for the “arduino part”)

Electronic materials:
-arduino uno
-motor shield rev3
-2dc motors
-potentiometer

Thanks for reading (sorry for my english, i m french)

Quentin

I would go with an optical encoder to measure the angle for a couple of reasons. It will be difficult to find a pot that goes 360 degrees. Most single turn pots cover about 270 degrees and if you use a multi-turn pot you lose resolution. And pots usually have at least some drag to overcome (which may not be a problem with the motor driven pointing). You can get encoders that have a home position output as well as the count, so you turn the generator head to home then turn in increments and do your measurements. Make sure that the maximum output voltage from the generator will not go over the maximum allowable input to the ADC.

Hello Quentin. Welcome.

What is the scale of this project? The size will dictate what power the motors will need to have and that will determine if the shield will be able to handle the power required. Why 2 motors? How will you be able to determine if the output of the turbine is relative to wind direction or wind speed?

  • Scotty

Groundfungus:

For the potentiometer, i found one that can turn 10 times and it has a little drag. I don t have any optical encoder. In this case, is potentiometer still a problem? My wind turbine produce a maximum of 3V. Thank you very much for your quick reply

Scotty :

It's a very small wind turbine (30 cm). One motoreductor is used to turn the wind turbine The other is used to produce energy, so as a generator. I made the wind turbine prototype and it turns with a 3V electric cell. I don't care about the wind speed or direction. I made a mistake in my presentation : i don t want to have my wind turbine in front of the wind, i just worry about produced voltage. I want to produce a maximum : in front of wind or not

The problem is, you have no way of knowing whether your turbine is in perfect alignment with a gentle breeze OR is it out of alignment with a stronger breeze.

You also have the issue that potentiometers usually have a stop on them that will cause them to be destroyed if rotated around a complete revolution.

At the end of the day, the most effective way of achieving this task is a simple vane attached behind the turbine to allow the wind to reposition your turbine directly.

Use the arduino to control other parts of your project.

Unless this is a very large wind turbine (tens of kilowatts) I strongly suggest you use a windvane to steer the turbine rather than wasting the electricity that it generates to drive directional motors.

Unlike solar panels a wind turbine will need to change direction very frequently.

...R

Ken F:

I agree with you. Maybe i can control loop the turbine. Ex : If my turbine is at 15°, it turns to 16° if Voltage is higher than at 15° system keep on turning. Now turbine produce 3V at 35° and it turns at 36° but produce now 2,8V so it turns the other way

What about that?

Ken F and Robin2:

Sorry, i didn t explain the goal of this project. My project is to build a model we can use for the real wind turbine. So i can t use a windvane to steer the turbine.

Thank you for answers :)

Quentin

qbarbato: Sorry, i didn t explain the goal of this project. My project is to build a model we can use for the real wind turbine. So i can t use a windvane to steer the turbine.

If you are designing a model of something that may later be reproduced at a larger size it must take account of the energy economics of the full sized machine.

I guess 100kW and up wind turbines have powered steering - I certainly have never seen a wind vane on one :) . I suspect they use a small wind vane to detect wind direction. It may even be necessary to have the direction detector some distance from the turbine so it is in free air.

Even if the wind direction does not change, the wind strength can vary enormously from moment to moment with correspondingly huge changes in power output. Power output cannot be an indication of wind direction.

...R

1) in practice, multiple wind turbines with a windvane, will all be pointing in different directions.

2) a vertical turbine will not have direction

3) an optical encoder can be made from a few sensors and a printed sheet of paper.

http://makezine.com/2006/02/19/how-to-make-an-optical-en/

Yes i agree with you.

i will create the two system : one control loop with the produced voltage and one control loop with a little windvane. I will compare both and choose the most powerfull (surely with windvane)

Thanks you for all answer!

BUT Now, i would like to know how to do it with arduino.

I explain : i dont know anything about arduino. Where can i find basic functions adapted for those systems? How can i print measure of my sensors on arduino software? How can i control my motor with arduino?

Quentin

qbarbato: i will create the two system : one control loop with the produced voltage and one control loop with a little windvane. I will compare both and choose the most powerfull (surely with windvane)

I don't think this is a valid concept. I suggest you collect data from both systems and compare them. My guess is that short term changes in power will not necessarily indicate a need to change direction.

I explain : i dont know anything about arduino. Where can i find basic functions adapted for those systems? How can i print measure of my sensors on arduino software? How can i control my motor with arduino?

Now that we have separated the "real" system from the Arduino based demo system it would be useful if you could describe (again?) what the demo system will involve - the mechanical arrangements and the data collection and control proposals.

...R

First system : Windturbine is control loop with the produced voltage. If the produced voltage is rising i continue to turn my windturbine, if the produced voltage is decreasing i turn the windturbine in the other direction. To do that, i put information of voltage (produced by generator) in my arduino card. My arduino tell to my motor (which turn windturbine) if the voltage is decreasing or not. How can i do that with arduino (the programm)?

Second system: Windturbine is control loop by a windvane (with a potentiometer wich can turn on itself). The motor which turn the system have to follow the direction of potentiometer. To do that, i put the information of potentiometer in my arduino card and the program have to tell to my motor how to turn.

I hope, i am understandable

Thank you for your reply.

You ask how to write a program for the first system but not for the second system. Does that mean you know how to program the second system.

I'm not going to help with the first system as, in my opinion, it is quite impractical. For example, suppose the power drops how will you know which way to re-orient the turbine? How will you know if the power has declined because the wind speed has changed without any change in direction. What will you do if the wind speed rises?

...R

Monitor the energy production of a wind turbine with GREEN POWER METER : http://www.instructables.com/id/Green-power-live-data/

I think it's a great idea. It's only a proof of concept and it will demonstrate a lot of the features that the other posters are criticising.

Since this is a desktop demonstration, you don't even need 360 degrees rotation on the turbine. Think about the 10-turn pot and the 1024-count Arduino analog resolution. You will only get 100 counts in each turn, so worse than 3 degrees resolution. Some more analog circuitry will be required to expand the resolution.

Don't attempt to power the Arduino from the turbine. You need steady power, such as from a battery. The motor turning the turbine will need adequate power too. Don't attempt to use the 5v power from the Arduino to turn the motor.

I have helped design several multi kW vind turbines. One of the hardest things to do was the aligning of the turbine. The other one was the control of the generator. The reason for this is that land based turbines experience turbulent wind. That is wind constantly changing direction and speed especially in lower wind speed that are much more frequent. The best solution we found was a ultrasonic windspeed/direction meter which had its outputs filtered.