Author Andrei
22/07/2019
This is a record of a project that's still in development. The eventual goal is that this type of motor/alternator can become a parametrized open source design. A user should be able to enter some parameters, like torque, speed, current, volts/rpm, common magnet sizes and perhaps space available, and a series of 3D printable .stl's and .dxf cut files should be generated. What Drewrt done is to create a platform that can validate a simulated design, which can then be evolved to a more optimal device by community. For the creator purposes it can be driven by a variable speed motor (surplus from cordless drill, with step down gearing), and shaft torque input measured, as well as V and Amps out, allowing real efficiency to be generated, and the expected turbine loads to be simulated.

The PMA consists of 3 assemblies, each assembly containing or using a variety of parts and materials. From top (bearing side) to bottom (stator side), 1. Bearing Carrier and Top Bearing Array 2. Stator 3. Lower Magnet Array 1.The Bearing Carrier and Top Magnet Array For this I used 3D printed parts listed above 150mm8pole upper mag and bearing support CV5.stl, bearing side inner plate bearing side outer plate 1" ID self aligning bearing (like used in standard pillow blocks++add internet link), 25' of 24g galvanized steel wire 15' of 10g galvanized steel wire 2 rolls coarse steel wool. Optionally the heavy steel wire and steel wool could be replaced with steel backing plates, laser / water jet cut, or a 3D printed magnetic backing plate might be possible (but heavy some steel wire is still a good idea as it will resist plastic deformation over time).

The controller is programmed such that as the turbine speed changes (or alternator voltage rises), the alternator is connected or disconnected, a thousand times per second or so, to match the load programmed for that speed or voltage.

Apart this post, if you have your own project and you need good quality PCBs, consider using the services of JLCPCB.com which will offer you quite good services, I use their services a lot of my PCBs.

Consider supporting ELECTRONOOBS on PATREEON.