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Discussion Starter #1 (Edited)
So a 1400horsepower EV wasn't enough at Team Lonestar... Here is our 2000HP Lonestar BLDC motor. it is 10" diameter, 14" long, 215lbs.. We have a direct bolt up to a Lenco CS2 automatic transmission. Motor will be fed 7200amps across 8 phases. Dyno work shows about 95-97% efficiency. This is over 550lbs lighter than our DC Series quad system with overdrive that only made 1400HP and was sort of self destructive at 8000amps.
 

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Discussion Starter #3
That is, wow, so AC is moving in on 1/4 mile machines?
Well, I am not using a commercially available system and converting it to make 2000HP. I had to find someone to help me build one that is purpose built for drag racing.
Look at trying to do this with Rhinehart and AM Racing stuff... Lots of money.

well this isn't cheap either....

This motor really has standing one mile written all over it too.....
 

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so I don't mean to pry, but BLDC because more area under the curve I recon vs sine? 8 phases, because again less inductance and more area under the curve (and a nod to smaller torque ripples)? Very interesting.
 

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Discussion Starter #7
so I don't mean to pry, but BLDC because more area under the curve I recon vs sine? 8 phases, because again less inductance and more area under the curve (and a nod to smaller torque ripples)? Very interesting.
"DCB", what's that stand for?

Yes you are right on.....

Prior to this incarnation.....
We investigated building a 1000HP ACIM drive and a convert a ACIM motor. We just couldn't make the HP without two LARGE AC motors. nearly 600lbs and that was only 1000HP.
I actually have a nice 1000HP ACIM inverter built, but the motors were heavy and just couldn't meet my performance goals.

The BLDC motor drive system is so much simpler, (the capacitor reduction alone is amazing) The short duration motor power to weight ratio, is about 4:1 better than DC series. (less torque at 0 rpm thus the three speed)
but Yes, the designer of the motor is a big fan of the high phase count, simpler on/off switching at much lower PWM freq. We expect the efficiency alone is going to save us battery 400Horsepower and turn it into actual rear wheel horsepower.
 

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you may need like 8 *full* bridges to get full reversal (push and pull) on each phase, once you get past 3 phases IIRC.
 

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Discussion Starter #11
So 8 phases is 8 half bridges firing with a 45° phase offset? I guess no sine modulation but simple square waves?
Amazing, subscribing.
Any info on your AC build? Was that with the kit?
Simple square waves, huge efficiency increase.....

The 1000HP AC project using your kit got to about 10HZ and we extrapolated out the power and the size of the capacitor bank and the weight of the motor needed, and it just wasn't competitive to what we were seeing from the power to weight ratio of BLDC. And I think you will see when this is complete, the power of 2000HP to roughly 200lbs is going to be about 10HP/lb, that is simply hard to touch......

The 1000HP AC project with your kit inside is with Adam Clark, who thinks it could still work for large trucks. We will keep you informed if we go up to the next level.
 

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yah half bridges are fine if accounted for. With enough phases you can think of them as commutator bar replacements :) and you can use a ring topology for series current (x2) or star for "massively" parallel (think lap winding with a brush per commutator bar, it is counter-intuitive to delta-wye as more phases means more parallel paths in star). The latter (star)definitely sounds like a solid approach for thousands of amps in an ac machine (each switch only has to handle 1/8 of the total current).
 

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Does this have any active cooling or just passive? I would be curious to know what the continuous hp rating would be for a motor that size. I would suspect it would be enough to keep a small car cruising down the hwy...

Sent from my STV100-1 using Tapatalk
 

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It would be enough to push a battle tank on the highway. I don't think there is enough metal in a small car to even hold it in place.
I imaging the duty cycle is similar to a series DC on this, depending on the cooling means, if there is any. If it's a closed case with no active cooling (this wouldn't surprise me on a drag motor) then it may not be good for much more than 40hp continuous. Still that would be enough for a larger sized car to hold a steady hwy speed.

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