Halbach PM generator

thingiverse

After examining https://www.thingiverse.com/thing:1693579, I decided to create my own design using 44 N50 magnets. The prints turned out well, and I will upload pictures later. My design differs from others in that it includes a case for mounting the stator winding using 3mm cap screws and all-thread rods to secure one half of the winding to the stator cap. This allows for easy assembly and disassembly. Blender files are included, with a scale of 0.1 in Cura. This is a work in progress; I will perform field tests in a few weeks when my magnets arrive from China. Another key aspect of my design is its use of irregular-sized bar magnets to test the real-world effects of varying magnet sizes on performance. This approach allows for cost savings, as irregularly sized magnets are cheaper than perfect rectangular magnets. I discovered that small magnets require precise placement within 1MM of the magnet face, which makes an outer frame ineffective. I don't have a Halbach version yet, but I do have a longer, larger rotor that can work with standard N-S magnet arrangements using my stator caps and a 10MM bolt or all-thread as the shaft. This design utilizes 100mm x 10mm x 3mm N50 Bar magnets. Next steps include: 1. Integrated cooling 2. Halbach frameless for small magnets The STL file "68mmfaceless" is a design to improve efficiency, but it won't work with my stator assembly. By pushing the magnets to the outside and using CA glue, I can minimize space between windings and magnets, yielding better results. I plan to integrate a fan impeller in the design. My intention is not for low-speed applications; instead, I want to test the generator's limits by placing it in a plastic box and pushing it as far as possible before it fails. I've learned that irregularly sized magnets perform just as well or better than rectangular ones when arranged in a Halbach array. UPDATE 6/29/2017: This morning, I rewound the generator with 5 winds of 0.25MM (30AWG) magnet wire from an old transformer. The results are much better: with the drill, I generated 0.538VAC, and at about 10KRpM, I achieved 1VAC. I've ordered more wire to attempt 200 windings and a 2:1 transformer to reduce voltage and double current. I plan to assemble the next rotor with CA glue and electrical tape or heat shrink to secure the magnets and minimize space between them.