Hallo,

vielleicht kann mir jemand einen guten Tip geben:

mich interessiert das Thema Pitchverstellung mittels Schrittmotor. Die mechanische Komponente ist dabei nicht das Problem.

Meine Frage - was muss realisiert werden, um aus der Windgeschwindigkeit und der von mir erstellten Tabelle "Anstellwinkel bei Windgeschwindigkeit" - daraus ergibt sich "Einstellposition für die Stellmechanik" das/ die Steuersignal/-e an den Schrittmotor zu geben und wie kann die Positionierung ev. kontrolliert werden?

Ich weiß, was ein Schrittmotor ist, beabsichtige einen Permanent-Magnet-Motor zu wählen. Die Windgeschwindigkeit soll über einen herkömmlichen Windmesser ermittelt werden - wie also muss die Steuerungselektronik gewählt und gefüttert werden, damit etwas brauchbares herauskommt. Gibt es ev. Bausätze für solche Aufgabenstellungen?

Ziel soll ein einfacher, zuverlässiger Aufbau sein - natürlich auch kostengünstig umsetzbar.

Danke für Tipps und auch gern Hinweise auf einschlägige Literatur, soweit sie nicht nur von diplomierten Elektronikern verstanden wird.

Grüße

Christian

Evtl Schmitt-Trigger -> Integrator -> NE555 -> Treiber oder halt per Microcontroller.

Hi Chris.

I have a 3 meter windturbine with automatic pitchcontrol running 4 years without problems.
Blade angle regulated by an actuator ( cordless drill 9 volt ), any compact actuator can be used.
Rpm counter and Arduino microcontroller drives blade angle fore and backward.Pitchcontrol


https://www.youtube.com/watch?v=69HZD4rG__U

https://www.youtube.com/watch?v=9jaz3soqXLo

https://www.youtube.com/watch?v=MRVGYVrgsdc

Video Blade Pitch verstellung and steppermotor and Arduino m-controller.

https://www.youtube.com/watch?v=n0du4-PQn1Q

great stuff - nevertheless I prefer pure mechanics...or electric systems that are fail-safe. What happens to a system like the one shown in the video during a power cut...maybe in a storm?

Hi Max.

Good question. I think a 90 degrees retractable tail with a pull-drop -line and a small winch.
An extra system with flyweights on the hub can be an option but makes it complex.

Rgds. Frans.

Some stuff I don't really get!
There's anybody building a pitch-control being not really peanuts.
And then one can detect fiber rotor blades without twist and the shape is also questionable.
"Design" is something where parts fit.
I will hear "it works"?
----
And if your pitch control is too slow there can be problems with system oscillation- take care!
I don't know how fast stepper motors are.
---
In big machines accumulators are used in the hub in emergency case.
Or a battery of gold caps. Accumulators don't like to be turned always...

Arminius

solution would be to pitch using the stepper motor and have a backup spring system that actuates in the other direction - stall. That way it would be quite easy to install a fail safe setup.

For turbines as small as we build them I prefer pure mechanics. I for example really like the system that the later Jacobs turbines use. I think that one offers a lot of possibilities for improvement in terms of getting it to work with electrics as well as pure mechanics.

max

Good to find a way for a mechanical failsafe in case of electrical powerloss with active pitchcontrol.
I will think it over. Normally the furling tail is working good with the electrical brake as well.
But sometimes there are severe windspeeds that those don't work as we wish.
In Scotland during the last heavy storm at Hugh Piggott's place there are 35 windgenerators and 9 of them failed . Runaway ,burned stators , etc.
Fortunately Hugh was able to repair the mills cause the small community depends on it.
Today we have here windspeed 7 - 8 Bft. My windmill is in feathered prop position. Feels good.

Rgds. Frans.

Furling sometimes does behave in strange ways...which is why I would not recomment to use it for turbines with more than maximum 5 m in diameter, also because it will work slow on bigger turbines...