It's pretty horrifying the stuff that universities throw out..

In my younger days I knew the guy that used to pick up the waste bins from the Atomic Energy Commission laboratory in the UK, I got him to make a detour to my place where I got some excellent pickings!
Max.

 

In my younger days I knew the guy that used to pick up the waste bins from the Atomic Energy Commission laboratory in the UK, I got him to make a detour to my place where I got some excellent pickings!
Max.

I also fell heir to a nice Weller station with desolder pump, soldering iron and hot air pencil. It was property of the Royal Air Force but the weapons systems now are so complicated that they can't be repaired by hand like they used to so they binned all the repair stuff.

Just last week we redid all the pins and bushes on a piece of farm machinery using our lathe and a whole box of hardened pins that a local dealership were scrapping because they ordered too many. Shameful the waste in modern society but I suppose that could be a thread all on its own

My new motor should arrive this week so I'll hopefully have some progress pics in a few days.

 

My new motor should arrive this week so I'll hopefully have some progress pics in a few days.

Looking forward to seeing how it turns out!.
Max.

 

Would it be easier to wind this as a "hairpin winding"? Most of the EV motors and even the new high amperage car alternators have switched to that style of stator winding. Doing a rewind on a normal induction motor needs to use a stepped type winding form doesn't it? To get the necessary winding pattern to fit the slots in the stator core.

 

Would it be easier to wind this as a "hairpin winding"? Most of the EV motors and even the new high amperage car alternators have switched to that style of stator winding. Doing a rewind on a normal induction motor needs to use a stepped type winding form doesn't it? To get the necessary winding pattern to fit the slots in the stator core.

I hadn't heard of this style of winding but a quick search has thrown up some interesting papers on the matter. A glance through the first paper I came across would suggest that a hairpin winding would require the stator slots to be rectangular so that you can form the conductor from a rectangular copper bar twisted to shape.

I'm going to try and get some more reading done before my "test machine" arrives!

 

I read somewhere that both Tesla and GM use the hairpins in their motors. And I don't think square or rectangular wire is a real requirement, it was just used in the from scratch design. But the square magnet wire is easily available too.

I have a stalled project to make a SRM(switched reluctance motor) and am planning on doing it with hairpin style stator wiring.

 

I read somewhere that both Tesla and GM use the hairpins in their motors. And I don't think square or rectangular wire is a real requirement, it was just used in the from scratch design. But the square magnet wire is easily available too.

I have a stalled project to make a SRM(switched reluctance motor) and am planning on doing it with hairpin style stator wiring.

I know certainly that Tesla are using induction machines in part because of the potential volatility of relying on permanent magnets from China. I'm not sure how much information is in the public domain though.

I think it would be fair to say there has been a flurry of interest in induction machines for electric vehicles of late. There's certainly a lot of glamour surrounding more exotic machine topologies but at the end if the day if it can be done with a simple and cheap machine then surely that's the way to go.

 

I think it would be fair to say there has been a flurry of interest in induction machines for electric vehicles of late. There's certainly a lot of glamour surrounding more exotic machine topologies but at the end if the day if it can be done with a simple and cheap machine then surely that's the way to go.

I don't keep up with it any more, but don't all of the really successful ones use induction motors? I personally think if the same amount of money and time was spent on the SRM it would surpass the induction motor for this application. It's just that SRM's were on the wayside for so long it's easier to keep on with the induction motor. But the research is out there, and a 3 phase inverter is what both motors use. A SRM is an easier to wind motor, because of it's salient poles verses the induction motors distributed poles. And the SRM uses no permanent magnets like a brushed or BLDC motor. But I'm just a hobbyist so what I think makes no difference.

 

I don't keep up with it any more, but don't all of the really successful ones use induction motors? I personally think if the same amount of money and time was spent on the SRM it would surpass the induction motor for this application. It's just that SRM's were on the wayside for so long it's easier to keep on with the induction motor. But the research is out there, and a 3 phase inverter is what both motors use. A SRM is an easier to wind motor, because of it's salient poles verses the induction motors distributed poles. And the SRM uses no permanent magnets like a brushed or BLDC motor. But I'm just a hobbyist so what I think makes no difference.

To tell you the truth, I couldn't have told you what a switched reluctance machine was. Whenever I heard those words I tended to think that it must be some complicated topology for niche applications Your post has prompted me to take a look at it though as a couple of my colleagues were speculating today that it could become the go to choice for electric vehicles. More reading to be done methinks.

 

In other news, I now have my test machine to destroy...... sorry...... "improve".

 

In other news, I now have my test machine to destroy...... sorry...... "improve".

Such a pity to destroy it!.......
Max.

 

Such a pity to destroy it!.......
Max.

Well I once destroyed one by connecting it in delta rather than wye so at least this one goes in the name of science

 

To tell you the truth, I couldn't have told you what a switched reluctance machine was. Whenever I heard those words I tended to think that it must be some complicated topology for niche applications Your post has prompted me to take a look at it though as a couple of my colleagues were speculating today that it could become the go to choice for electric vehicles. More reading to be done methinks.

All of the electronic power steering in ICE cars use SRM motors as far as I know. And a while back they were being developed as in the wheel motors for cars, hooked directly to the wheels instead of a drive axle. But like I said haven't been keeping up on this type of thing. Dyson's digital motor for vacuum sweepers is another one using SRM. Also a lot of mining equipment has switched to them.

SRM were one of the first electric motors developed, back in the 1800's, 1830 something if memory serves me. But nothing much after that the failing back then was commutation, it was done mechanically, but now with IGBTs and GTOs and other high power semiconductor devices it is coming alive again.