good mornin all
fanman here, its been awhile i know but work has keep me very busy these days, i have managed to do some more work on my 20 footer this summer, i started a large machine about a year ago,axial flux type, the disks are 29.5 inched wide hold 24 poles each and has 18 coils of 2 in hand #14 wire, 95 turns in each coil, that gives me 54 rpms cut in speed and the blades are 20 foot dia.
i had cast the stator disk as uasual and used ester that everyone is using, it casted out pretty nicely, with this machine i wanted to load test on ground before she flew, to get the numbers under controlled conditions, i hooked my truck up to the machine through a pto shaft and spun it up,
i got what i thought were pretty good numbers, the machine cut in at 54 rpms,at 85 volts 85 ac and we did rectifie and loaded into a 120 volt batterie bank, i ran the machine up to 36 amps ac which was app 50 amps dc to the batterie, and ran it there for about 12 minutedsrpm at that output was 115 rpms, it did indeed get hot, and a while running at that speed the ester started to dripping onto the floor, so we stopped the test run and as the stator cooled down it warped very badly,
well thats alot of money in copper wasted now, and i didnt much like that, so i decided to go a differnt way with the disk,
i made an open frame i will call it,made entirely out of 316L stainless steel, i found all stainless has some attraction the 316L has very very little almost nothing, then i made pockets for each coil to sit into,
to big a pic 1 it works very nicely so far i can put coils into it and in case of burnout replace ones as needed, no need to redo the whole plate,
underneath the coils you can see some rings that are going to pinch these coils together into the frame,
here are the top rings and they get e through bolt to the back ring and pinch them all together
and of course the bolts are all stainless steel and everything is insulted from the coils, now all that is left is to dipthe whole plate into insulting varnish to solidifie everything up real nicely, and i will be ready for another test run,
im willing to bet it will run a whole lot cooler now, granted my first test did not have the bbreeze to cool it like on the tower top, it got well over 200F inside the coils on the old stator, i did also measure that, the coil are itself you couildt touch it was so hot, and right next to the coil was cold, the ester didnt wick heat at all, i didnt have any powdermixed with it either,
i will be load testing again soon and will give results then
