A few days ago I posted the build instructions for a project of mine: WinDIY a 3D printed wind turbine.
Even though I still have some work to do, most of the functions of WinDIY already work. What unfortunately did not work yet is the main purpose of a wind turbine: generating energy.
Because the generator I have installed in WinDIY does not fit to the expected speeds of the wind turbine. While the generator delivers approx. 30W from approx. 20 revolutions per second(!), the wind turbine would probably be destroyed at this number of revolutions.
I guess I'll have to invest a few more hours at the workbench here 🙂 .
Since the generator works in principle, however, and there may also be scenarios to which it could fit, I want to present it here anyway. At least some tips for the development of your own generator should come out of it. 🙂
And why actually "Nerdiskerator"? This nickname of the disk generator (=disk generator) comes from "NERdiys DISK genERATOR"= Nerdiskerator. 🙂
Overview
- Disc generator, which consists largely of 3D printable parts
- The stator contains 12 manually or automatically wound coils
- The coils are potted with epoxy resin in the stator
- Two rotor discs with 20 neodymium magnets each
- Each rotor disc is supported by a ball bearing
- Three NTCs are also potted in the stator to monitor the temperature in the stator windings
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/172445-nerdiskerator-a-3d-printed-disk-generator
Electronics
Besides WinDIY, Nerdiskerator also has a few security features.
Three NTCs are encapsulated in this to monitor the coil temperature in the stator. Of course, this should not be too high, because the filament used can then become soft.
So that these sensors can be read and reacted to, some electronics is of course necessary. For this purpose I started with the development of a circuit board, on which all necessary components are accommodated.
You will find more information soon here on Nerdiy.de.
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:
Great idea to build a generator yourself. I've also been toying with the idea of building a wind turbine completely myself for a long time.
Regarding the generator, however, the plans in my head look a little different and I think that this would also increase the low power of your generator.
With your construction the magnetic flux remains open. I try to explain this with simple ASCII graphics: [NS] represents a magnet, that = the coil
[NS]=
[SN]=
[NS]=
The magnetic field lines (similar to the electric current) always try to take the shortest path, whereby they spread more easily in metal (or magnetically conducting materials) than in air. In the above example, they only flow from the left [ to the right ] through the air. This represents a very high magnetic resistance and only a few field lines actually "cut through" the winding, which is the prerequisite for current generation.
Better would be an arrangement in this form:
[NS]=[NS]
[SN]=[SN]
[NS]=[NS]
I.e. magnets on both sides of the coils. Just by holding the magnets with the opposite poles against each other, one already notices the strong attraction that arises from the fact that the magnetic flux strives to reduce the resistance that the air between them represents.
The whole thing would be optimized if one N and one S pole were connected on the outside (opposite the coil, marked by the 3 I) and a magnetically conductive material amplified the flux through the coil, like the screw in your case (air acts like an insulator).
I[NS]=[NS]I
I
I[SN]=[SN]I
I
I[NS]=[NS]I
My tip for the magnets would be to use them from the good old spinning hard drives (I've been collecting them for years for my project....). I found the thickest ones in the older server disks (about 10GB). The kidney shape and arrangement of the poles are just ideal for such a project. In addition, it gets a particularly sustainable touch if the difficult to manufacture Neodyme are reused and do not end up on the garbage dumps.
Another tip: If the screws become very warm, this is due to the loss of magnetization. You should then use transformer sheet metal. Theoretically, the ferrite rods of the medium wave antennas of old radios would also work.
Keep reporting on your project, I follow it very interested and look forward when it "flies"!
Hi Mario,
thank you for your comments. I am currently working on a new design for WinDIY. I post there relatively regularly under the hastag https://www.instagram.com/explore/tags/windiy_2/
There's also a post on the current design of the new generator 🙂 .
Best regards
Fabian