Auf einem Camping-Trip abseits von moderner Infrastruktur fällt einem schnell auf wie sehr man sich eigentlich daran gewöhnt hat, dass Strom immer und überall irgendwie verfügbar ist. Das doofe: Meistens fällt dies auf, wenn der Strom gerade nicht da ist.
Für diesen Fall gibt es mittlerweile Powerbanks. Aber was wenn die Powerbank leer ist? Unterwegs aufladen ist ohne Strom schwierig.
Vor dem gleichen Problem stand ich vor ein paar Jahren während eines Camping-Trips. Damals hatte ich sogar eine mobile Solarzelle dabei. Diese lieferte zwar etwas Energie, aber mangels Sonne nicht genug. Die Sonne schien einfach nicht kräftig genug. Was ich dagegen hatte war Wind.
Und so entstand die Idee Wind-Turbine zu bauen die sich mit dem 3D Drucker selbst herstellen lässt.
Zunächst vergessen bekam diese Idee dann frischen Aufwind, als ich auf dem Flohmarkt über ein paar Neodym Magnete gestolpert bin. Für kleines Geld bekam ich dort Magnete mit denen sich doch sicherlich auch ein passender Generator bauen lässt.
Mit der Zeit ist daraus das hier präsentierte Projekt entstanden. Weiter unten findet Ihr dazu auch detaillierte Bauanleitungen der einzelnen Komponenten.
Important: The wind turbine is currently (11.10.2020) not yet running perfectly. The blades still need to be adjusted and also the generator does not quite fit the characteristics of the wind turbine. So there is still some work ahead of me. But maybe the shown components are a suggestion for everyone who is working on his own design of a 3D printed wind turbine 🙂 .
Overview
- Windturbine aus 3D-gedruckten Teilen
- HAWT Design
- Rotordurchmesser von 0,5 bis 1,2 m möglich
- 3D gedruckte Flügel
- Verwendet einen 3D-gedruckten Scheibengenerator zur Energieerzeugung
- Sicherheitsfunktionen durch aktive Pitch-Einstellung der Flügel, mechanische Bremse und elektronische Bremsfunktion über den Scheibengenerator
- Kann mit jedem “normalen” FDM-Drucker (20 x 20 cm Bettgröße) gedruckt werden
Videos
Images
Below are a few pictures of various components from different stages of development.
Development
I have documented the development and the individual difficulties for the most part on Hackaday.io. You can find the link here 🙂
https://hackaday.io/project/172328-windiy-hawt-wind-turbine
Anleitungen zum selber bauen
Der Aufbau von WinDIY besteht aus mehreren einzelnen Segmenten. Da alle Teile auf einem 3D Drucker mit einer Druckfläche von 20x20cm gedruckt werden können, müssen die einzelnen Teile nach dem Druck natürlich noch zusammengesetzt werden.
Dabei werden Größtenteils M3 Schrauben und Muttern verwendet um nicht zu viele unterschiedliche Teile zu benutzen. Detaillierte Materiallisten findet Ihr jeweils im entsprechenden Artikel.
- Flügel aufbauen: WinDIY – Flügel der Windturbine aufbauen
- Windfahne aufbauen: WinDIY – Windfahne zusammenbauen
- Nabe aufbauen: WinDIY – Nabe inkl. Mechanik aufbauen
- Drehturm aufbauen: WinDIY – Drehturm aufbauen
- Hauptachse aufbauen: WinDIY – Die Hauptachse zusammenbauen
- Pitch-Aktor aufbauen: WinDIY – Pitch Aktor zusammenbauen
Electronics
WinDIY verfügt wie oben erwähnt über ein paar Sicherheitsfeatures. Damit diese kontrolliert angesteuert werden können ist natürlich etwas Elektronik notwendig. Dazu habe ich mit der Entwicklung einer Platine begonnen, auf der alle notwendigen Komponenten untergebracht sind.
The following components have been installed on it so far:
- Three-way bridge rectifier
- Step-down controller
- Three independent charging circuits for one LiPo cell each
- Three I2C motor drivers to control the motors of the brake actuator and the pitch actuator
- various current and voltage sensors to measure the generated and consumed energy
- Connections for two Hall sensors for measuring the generator speed
- Connections for three slide resistors to be able to measure the positions of the pitch actuator and the brake cylinders
- Connections for two force sensors to be able to measure the contact pressure of the brake cylinders
- Connections for four NTCs to be able to measure the temperatures of the generator windings as well as the load resistance.
- Connection to be able to discharge the rectified voltage to a load
- Connection and electronics to be able to connect a load resistor PWM-controlled.
- Vibration sensor to detect abnormal vibrations
- two temperature sensors to monitor the temperatures on the PCB
- an electronic compass
- one micro-SD card slot
- a climate sensor for measuring the ambient temperature, humidity and air pressure
Software
The software is developed using the Arduino IDE. You can find the current state in the Nerdiy-Git under the following link:
I read there are problems with the speed? I'm not 100% sure about the torque being produced but a well running planetary gear in the rotor name should increase the RPM's significantly and wouldn't take up much space?
Awesome project by the way
hey daniel,
danke für den Vorschlag. 🙂 Ich arbeite aktuell daran die gesamte Konstruktion etwas zu vereinfachen. Das Planetengetriebe hatte ich dabei noch gar nicht auf dem “Zettel”. Danke für den Hinweis. 🙂
Best regards
Fab
Hello,
The magnets are arranged in Halbach? This increases the magnetic flux.
The 3-way bridge rectifier is a standard model with doids? Maybe try a MOSFET.
Diodes always consume some voltage - with bridge rectifiers this is twice the forward voltage. So with silicon diodes you lose 1.4 volts.
With MosFET you lose almost nothing - microvolts.
Bei Google mal “mosfet als diode” suchen lassen.
You are welcome to use this method in the voltage converter as well.
Wenn ausreichend Drehmoment da ist, aber zu wenig Drehzahl, vielleicht ein Planetengetriebe benutzen. So machen es auch die “großen”.
And wind the coils with more turns. This increases their tension and you get something out of it even at lower speeds.
Hey Michael,
it is not a Halbach arrangement. The built generator is also quite simple and not optimal due to the not really fitting magnets. You can get a small impression here: https://nerdiy.de/nerdiskerator-a-generator-from-the-3d-printer/
Die MOSFET Gleichrichter-Lösung finde ich auch sehr interessant. Allerdings hatte/habe ich etwas Respekt vor der korrekten Ansteuerung der MOSFETs und habe es deswegen erst mal etwas weiter unten auf “der liste” eingetragen. Andererseits sind die ersparten Verluste schon recht spannend.
Thank you for your hints. 🙂
Best regards
Fabian
I feel the same way with MosFETs. When I was training to become a power system electronics engineer, the first MosFETs that could handle 2 amperes were just coming onto the market. They were the size of 2 euro coins.
I just googled it out of curiosity and boredom.
I learned that a 3-phase rectifier with MOSfets is not as easy as one with diodes.
For example, 6 diodes are enough, but you need 12 MosFETs. Because you need a full bridge per phase, since the control must be taken from the opposite pole. That doesn't work with three-phase current...
Then I found another circuit with a control IC... LT4320 - also interesting.
I've included a link showing a complete circuit that should work even for 3-phase AC - or 4, 5, 6, lots...
There each MosFET has its own small control and can function as precisely as a diode.
However, he writes that he was not able to start the circuit without an external power supply for the control circuit. But that is probably true for a software simulation.
You should try it.
https://www.mikrocontroller.net/topic/375657
About the planetary gears... This is supposed to ensure that the generator rotates faster in order to induce higher voltages in the coils.
So I had the idea of attaching a ring to the outside of the propellers instead and attaching the magnets there. Outside then the coils.
A few words about the number of magnets and coils...
Any even number of magnets. The number of coils should be lower or higher by 1!
This reduces the starting torque enormously, since the latching forces of the magnets and coil cores almost completely cancel each other out. But then you also need a lot of diodes/MosFETs – two per coil.
Last but not least, you can design it as a wind turbine. Ie there are no propeller flights in the middle, but only at the outer edge. A cone in the middle of the turbine directs the air flow from the center of the turbine onto the wings, and the air should be rotated just in front of the wings to drive the propeller even more.
Then put it all in a tube. This prevents turbulence at the wing tips and that the air displaced from the center simply escapes outwards without driving the wings.
Now the part looks like an airplane turbine, only shorter.
Ok – now it gets even more intense…
The whole thing is now mounted on a mast. A gear wheel is mounted on the mast below the turbine.
Two smaller propellers are attached to the bottom of the turbine. These must be at an angle of 90° to each other. They drive a differential via cardan joints or bevel gears in such a way that the differential is balanced when the propeller is subjected to the same flow – ie it does not rotate.
If one of the propellers has a stronger flow because the wind direction has changed, this propeller turns faster than the other and the differential turns. It engages with the gear wheel attached to the mast and turns the turbine back into the wind.
The advantage over a fin is that the turbine turns slowly into the wind and does not start to flap if the wind changes direction unsteadily.
Are the metal screws in the coils as iron cores?
Well, not bad for a first try.
But it is better to use transformer sheet metal. So off to the transformer sheet metal shop 🙂
Transformer sheets are thin iron discs that are isolated from one another and stacked to form an iron core.
During my training as a power plant electronics technician, we were all allowed to build a transformer.
Stack the transformer core included, put on the previously wound plastic winding body, solder on the terminal strip.
The (manual) winding machine always kept the wire under tension. Tight and tight is better - The magnetic flux decreases with the square of the distance from the core and with it the transmitted power.
A ferrite core should give even better results.
The reason for this are eddy currents in the iron core, which arise when the magnetic field also induces currents in the iron core. Of course, the core immediately shorts them out, causing the iron core to heat up.
This heat is then no longer converted into electrical energy...
Die isolierten Eisenscheiben reduzieren die Stromwirbel enorm. Ein Ferrit-Kern besteht aus gesintertem Material, in dem die Stromwirbel nur noch Millimeterbruchteile Platz haben und so kaum noch Energie “verbraten”.
The only thing missing is a buck-boost converter to be able to generate usable voltage at low speeds and an optimal point control that can adjust the distance between the magnets and the coils so that the best efficiency is always achieved at different wind speeds .
When you've got everything ready, present the thing to Nasa. There is more wind than sun on Mars!