Learning about different Electric motors.

[Lebowski]

you can try to run it with the controller using the 'sensorless self start'... no clue whether it will work but you never know

how are things going with the 18FET output stage ? I haven't seen any updates lately...

 

[Arlo1]

you can try to run it with the controller using the 'sensorless self start'... no clue whether it will work but you never know

how are things going with the 18FET output stage ? I haven't seen any updates lately...

That would be pretty awesome.

I blew them all up. Took a brake while I waited for more boards to come in. I had ordered new boards for the TO247 package style fets just after Xmass and they just came in. I will be on the controller project again very soon.
Apparently the good controllers run a encoder with a measured slip other then that which could just use one hall input I think a controller based on your chip would work lebowski.
EDIT: But it would need some tweeking in the code.

 

[Arlo1]

Just spray wd40 in it and drop it on the floor they say.... It will be fun they say... You can build your own custom AC inducrion motor they say... Now my back hurts...
Now thats a Stator! Im going to get another and make a KICK ASS BLDC!

 

[Arlo1]

Ok anyone know where I can find some aluminum pipe or tube that I can machine to 8.25" id and have enough thickness for strength to hold all of this together? I need to slide the stator inside some aluminum then I will either machine some fins or water cooling passages but I can't find any aluminum that size.

 

[salty9]

Arlo,

I don't know exactly what you want to do but could the existing case be modified to meet your requirements?

 

[Arlo1]

Arlo,

I don't know exactly what you want to do but could the existing case be modified to meet your requirements?

I am going to find aluminum for making a new case. It should be lighter when done but more importanly it will cool the stator better.
So what I need to do is make a case (frame) for the motor out of aluminum and end caps. The end caps are a peice of cake but the part that holds the stator will need to be 8.25"id and it seems this is a number thats going to be hard to find.

The old case was steal the end caps and case weight was 70lbs. And I cracked it getting it off
Aluminum will be lighter and conduct heat better and will give me the option for water cooling as well.

 

[bigmoose]

If we start in steps, as in leaving water cooling for later... because I think you should oil mist cool the innards... OK, I'm biased for that method of cooling.

If you buy this approach. Take a sheet of 1/8 in Al and roll form it to fit the stator outside diameter. Weld the seam and work it to the right ID. (I am not a sheet metal worker and don't know how specifically to do this.) Machine the ends to get everything square. Machine end bells that use injected ATF to lube the bearings and cool your rotor, spraying oil onto the end turns. Suction sump the housing. I think I sent you the BGSU paper on what this looks like.

All the best in the conversion. The BGSU guys did just what you are doing. They converted a 10 HP Lincoln Electric Industrial Motor to a 100 HP "Power Dense" design for use in an electric Bus. It is in the paper. That is 100 HP continuous also if I recall correctly. I have seen the bus, the controller and the motor in person, shame it's all scrapped out now.

 

[Harold in CR]

Ok anyone know where I can find some aluminum pipe or tube that I can machine to 8.25" id and have enough thickness for strength to hold all of this together?

Here is a place near to you that might be able to help.

They show 8" Sch 10 pipe that is 8.25 ID X .188 wall.

Then, they show 10" Sch 160 that is 8.5 ID X 1.125 wall.

Maybe weld up as a water jacket. That would be roughly .312 spacing ??

Anyway, here is the contact info.

Alcobra Metals, Inc. Phone-in Orders Welcome!
4510 North Freya Phone 509 482 4435 Fax 509 482 4512 Toll Free 800 239 5608
Spokane, Washington 99217 E-mail: info@alcobrametals.com

 

[Arlo1]

If we start in steps, as in leaving water cooling for later... because I think you should oil mist cool the innards... OK, I'm biased for that method of cooling.

If you buy this approach. Take a sheet of 1/8 in Al and roll form it to fit the stator outside diameter. Weld the seam and work it to the right ID. (I am not a sheet metal worker and don't know how specifically to do this.) Machine the ends to get everything square. Machine end bells that use injected ATF to lube the bearings and cool your rotor, spraying oil onto the end turns. Suction sump the housing. I think I sent you the BGSU paper on what this looks like.

All the best in the conversion. The BGSU guys did just what you are doing. They converted a 10 HP Lincoln Electric Industrial Motor to a 100 HP "Power Dense" design for use in an electric Bus. It is in the paper. That is 100 HP continuous also if I recall correctly. I have seen the bus, the controller and the motor in person, shame it's all scrapped out now.

Thanks Dave. I will do all the reading I can. Here is a forum I joined that just started dedicated to Big AC induction motors what attracts me to induction is the broad rev/efficiency range. Power density still seems to be in the BLDC world but as it would happen all I have to do is make a new rotor to make one of these BLDC and in fact that's just what the Chinese motors are sometimes. One guy up island from me has one I think he said is was a 132 frame but controller problems plagued him so he swapped his car out to a dc motor/controller setup he is a moderator on the DIY electric car forums.
I was wondering how Tesla can get such huge numbers out of a small motor but then when you see there is a different relationship with AMPs/volts/turns/parallel strands/rpm poll count as compared to a BLDC motor you can see there might be a way to mod to big power. Cooling everything is definitely top of the list for modding for higher continuous power.

 

[Arlo1]

Ok anyone know where I can find some aluminum pipe or tube that I can machine to 8.25" id and have enough thickness for strength to hold all of this together?

Here is a place near to you that might be able to help.

They show 8" Sch 10 pipe that is 8.25 ID X .188 wall.

Then, they show 10" Sch 160 that is 8.5 ID X 1.125 wall.

Maybe weld up as a water jacket. That would be roughly .312 spacing ??

Anyway, here is the contact info.

Alcobra Metals, Inc. Phone-in Orders Welcome!
4510 North Freya Phone 509 482 4435 Fax 509 482 4512 Toll Free 800 239 5608
Spokane, Washington 99217 E-mail: info@alcobrametals.com

Thanks guys. My welder is worried about doing a bend on something thick enough but.... I will figure out something. He also says it will warp like crazy if we weld on something when its round but we will see. I love this kind of challange I will either find something round (billit wheels from a atv?) or make something up.... Not to worry. I will try making some calls monday.

 

[salty9]

I recall watching the Bremerton Naval Shipyard roll form steam accumulator tanks for carrier catapults from steel over 1 inch in thickness. The equipment used, massive but simple in concept, consisted of two rollers on fixed axles and a movable roller between them to apply pressure. The sheet was moved back and forth as pressure on the center roller was increased. The sheets eventually formed a cylinder about 12 feet in diameter.

 

[Arlo1]

If we start in steps, as in leaving water cooling for later... because I think you should oil mist cool the innards... OK, I'm biased for that method of cooling.

I agree with this as well. Oil cooling or even proper air moving over the windings. The thing is the stator housing can only suck so much heat out of the lamination's when the goal is to not let the windings touch the lamination's so a better approach is to cool the windings directly then move the heat to the out side so air or oil or air/oil mist or even air water.... Sprayed directly on the windings will be key. The rotor will also be heated and need cooling so maybe a smooth rotor with a case 1/3 full of oil.... Then machine and bead or sand blast the inlet and outer surface of the housing at the ends and the end caps to conduct as much heat out as possible.

 

[miro13car]

for clarity we should use therm: AC induction motor.
Tesla uses AC induction motor
I am wondering what is the cost of their DC/AC converter?
I am not surprised TESLA worked with AC proplusions, they have big expertise in AC drives for EVs

 

[emiyata]

Thanks guys. My welder is worried about doing a bend on something thick enough but.... I will figure out something. He also says it will warp like crazy if we weld on something when its round but we will see. I love this kind of challange I will either find something round (billit wheels from a atv?) or make something up.... Not to worry. I will try making some calls monday.

You can weld .060 AL tubing. You should get little to no tube distortion but if you don't want to take that risk, pack with wet sand.

 

[Arlo1]

Thanks its going to be machined anyways. I found a metal roller Im going to try to "Roll my own" tube. I will be looking at it Tuesday.
On another note I found a 1hp 1phase AC motor im going to rewind to 3 phase and see where I can get the power levels up to!

 

[crossbreak]

One thing I want to add: Separate excited motors can be hybrid: They are driven with fixed frequency. They start up as an induction motor, if they are near synchronous rpm, the excitation current is switched on, making them run as synchronous motor. The induction of a synchronous motor is zero, since rotor and field have no rpm difference so there is no fight against each other.

 

[Arlo1]

One thing I want to add: Separate excited motors can be hybrid: They are driven with fixed frequency. They start up as an induction motor, if they are near synchronous rpm, the excitation current is switched on, making them run as synchronous motor. The induction of a synchronous motor is zero, since rotor and field have no rpm difference so there is no fight against each other.

You talking about an alternator conversion?

 

[salty9]

Arlo,

This may be old info for you but if you do roll your own motor housing you should check into work hardening and stress relief.