3hp Motor Conversion Update

[dinges]

Andyman,

One more thing. My magnets 'stick out' at the ends of the stator. That is, about 1/3 stick out at each end. That way, I could fit another row of magnets. This is a bit of a waste of magnets, on the other hand, the widest part of the magnets still sees the stator core. Let me know if you this is clear enough, otherwise I'll make a drawing of it.

Also, I have very small spaces between magnets; from memory, about 1mm. I thought this was too little, because as you may find out when you order them, these magnets repel eachother quite strongly! However, when you mount them on top of a piece of steel, you find you can suddenly move the magnets almost next to eachother, with a very small gap, and they'll stay put! Now, admittedly, a rotor is round and not flat, but still.

If you could reduce the gap between magnets from 4 to 2mm, you'll gain (I think) 7*2mm = 14 mm (if you have 8 rows of magnets, this is a guess of mine). Now, 14mm, plus a bit of magnet sticking out at the ends, could mean you could add another row of magnets. Just an idea.

All this is just theory; as you know, I haven't yet fully finished a motor conversion... But more magnets can't be bad

[andyman5002]

I was wondering whether I should squeeze another magnet or two on the end of a row. Currently there is 5 mags per row and 3 rows per pole. If I added 2 more mags to get 7 in a row then there would be 1.1 mm gap between each one I think. But the majority of the two mags wouldnt cover the stator. The stator is 90mm long and the rotor is 112mm including the aluminium rims on the end. Im not sure whether any of the mag would be on iron material so poor flux transfer

Still need to give the mags more thought I think. I want maximum power without outgrowing the blades and stalling them. With my blade size I need about 25mph wind to get 1.1 KW available to the genny. Anyway im not going to rush it this time just gather information before I rush in.

Thanks Andy

[ghurd]

You may want to get a bunch of cheap neos and a small motor or 2 for a first try.

You can get an idea of the cogging and magnet placement.

Super glued nickel plated magnets can be snapped free and then placed differently.

G-

[strider3700]

I test/destroy a lot of electronic units with various IP rating.  IP 55 should survive rain over the long term but if the water pools along any of the seams it will get through.  Every IP55 device I've tested failed when submerged in a couple of inches of water for more then a minute but thats not surprising since it's not rated for it.

[andyman5002]

Now that I've broken the unit open the IP55 rating has gone?? I will have to reseal it with some similar water repelant or silicon.

The project hasn't advanced yet as I still need to find a suitable supplier for the aluminium tubing. Im surprised at the cost of the tube, for a 6 inch length of tube they wanted £60 or $113. Im sure I can find it cheaper, not sure what you guys pay for it, if thats the going rate then I will have to pay it.

Andy