12 kw rc motor

i like them lotus 7 kits . freind of a friend bla bla has one very fast

since ive been here though ive thought this would be a good sporty ev , may just do it if i dont go for the army truck
http://www.beckspeedster.com/generalproductinfo/550spyder.html
always wanted to get one and jam a HO honda motor in one


i wonder how many of these one could get in a planetary setup on the fly wheel of a little spyder. be fun as hell with a bonnet full o lipo

liveforphysics said:

I'm putting together some CAD sketches of coupling together 12 of these motors along the belly-pan of a lotus 7 kit to make an EV.

If I can mount the battery similarly low, I could make the lowest center of gravity lotus 7 kit in the world, and perhaps even the best handling lotus 7 in the world. Perhaps 350hp burst, 150hp continous, maybe 1,200-1,500lbs with driver.

Click to expand...

Nice! My thought of putting two into my '01 Triumph Daytona 955 rolling chassis pales in comparison....

Hi Luke,

liveforphysics said:

I'm putting together some CAD sketches of coupling together 12 of these motors along the belly-pan of a lotus 7 kit to make an EV.

Click to expand...

Would this make more sense (similar power and maybe similar price)?:
http://endless-sphere.com/forums/viewtopic.php?f=10&t=17217&start=30#p253473

Liquid cooled, permanent magnet, 8 pole AC motor. Up to 18.000 RPM, efficiency always over 95% (even on peak loads).

The motor is 27 cm in diameter. Length and weight depend on desired power. The weakest one is good for 30kW continuous/80kW peak and weights 42 kg.

The strongest weights 70 kg and has a peak power of 200kW.

The length depends on the power. The 80kW motor is 200 mm long, the 200 kW motor is 300 mm long.

We can also offer a reduction gear that adds 12 kg and reduces the RPM to a more ICE like RPM range.

The reduction gear adds just about 80 mm in length and 12-15 kg weight. The reduction ratio can be adapted to the specific use. We can lover the RPM to a "ICE like" range so you can use a standard differential. We can also make a reduction for a direct connection to the wheel but that setup would require two motors.

Click to expand...

Maybe Mitch, but then I need a $$$ HV controller, and a step-down gear box (and it's noise and complexity).


I'm really likeing the idea of a stack of these motors. I'm still CADoodling the best arangement to tuck in a tranny tunnel.

12 cheapo BLDC E-bike controllers. 1 Set of hall sensors in 1 motor to give the switching signal for all the controllers. Maybe even just do a master-slave setup off the fet drive of a single controller, running to external FET stages for the others that are mechanically locked in the same phase timing.

Maybe just start with 8 motors (96lbs of motors) and see how it goes. I'm pretty sure those things will handle bursts of 30kw pretty easily. That would mean 8 of them could give me 320hp burst, which should be enough for a first try at an EV build. In a car as feather weight as a super7, you can't really use even 200hp for more than 10 seconds at a time or so before the car has reached the limits of it's top speed stability, so the burst rate is more important to me than the continous power.

Jeremy Harris said:

I'm already working on a controller, Luke! I've been doing a lot of work recently on building a small, high current, controller. One thing I discovered, when looking through dozens of FET spec sheets, is that there are some surprises, as a big package isn't necessarily the best. Some may have spotted that getting heat out of the FET junction is the big issue that limits the current a single FET can handle. There's nothing much that can be done about the internal thermal resistance, and this tends to be similar for pretty much any package. The big packages offer the means to get heat out of the package more easily, but this can be done another way, I think.

I've found this FET: Yes, it's a small, surface mount package. BUT, look at the ratings and then think about this as a mounting option:

What if the power rails and the phase connections were solid copper bars, connected to internal finned heatsinks?

What if the FETs were soldered directly to the copper bars, providing not only a good electrical connection, but also a near-zero thermal resistance (no insulators needed)?

What if the controller had a small internal fan to keep the "live" heatsinks cool?

I'm thinking of a 12 FET power "board" using these FETs, driven by a 6 FET controller board. I reckon such a controller would comfortably handle well over 200 amps. In fact, in might well do around 150 amps on just 6 FETs. The downside would be the 75V FET Vds limit, but as the motor is rated at 60V max this shouldn't be too big and issue.

Any thoughts?

Jeremy

Click to expand...

Hi Jeremy - Your ideas posted here remind me how people with a similar goal often end up going down the same windy road!

I had looked into (and even bought a few) FETs using the same package. Having the source current go through 5 pins instead of one would indeed remove one of the bottlenecks of these devices. However, sometime latter I decided to stick with the TO-220's, as I found that it was too tricky to design a easy to assemble copper-bar based power stage using these surface mount D2paks.

As for soldering FETs to thick copper bars without stressing them too much *and* not pulling your hair out - good luck. I've decided to go solderless, but I still do use the tabs as an electrical drain connection anyways... it works very well, and I would not go back to solder.

This route led me to my last protoype, which I tested (months ago) at 200A per phase continous for a 12FET power stage (3006's @ 50V input, 60%duty). It was actually the 8AWG output wires that went over 100oC that was the limiting factor, specially the one doing PWM which heated up significantly more than the wire on the phase being held low. Needless to say, I was *very* happy about the results of this last design!

Since then though I have had many distractions and have not touched the controller, and was also discouraged a while by a potential small outfit interested in finishing the controller development together, but backing off after much discussion due to financial constraints (and it's the second time I've wasted time/energy negociating and having the other party back down afterwards). I guess my lesson is to do it myself, and just have fun with the technical stuff I really like doing instead of wasting energy on negociating association conditions and the likes. Sorry for this being off-topic BTW, but Jeremy's controller post caught my attention!

Pat

liveforphysics said:

I'm putting together some CAD sketches of coupling together 12 of these motors along the belly-pan of a lotus 7 kit to make an EV.

Click to expand...

Luke I've thought of this a couple f times since I saw the diyev guys using coupled 9" motors. How would this work with an ac system, would each motor need it's own controller?

I LIKE THAT MOTOR ! UP ON THE PICTURE HEY GUYS , ON APRIL 19 WE WILL HAVE ALL NEW MOTORS THAT HAL REDESIGNED : -HALL SENSORED , LIQUID COOLED (USE IT WITH OR WITHOUT IT ) . AND JUST TO TELL YA , HALL ALREADY MADE MOUNTS FOR CONNECTING 2 , 3 ,4 ,5 ... MOTORS TOGETHER AND A FEW MINOR CHANGES

Hi Luke,

Mitch said:

Would this make more sense (similar power and maybe similar price)?

Click to expand...

liveforphysics said:

Maybe Mitch, but then I need a $$$ HV controller, and a step-down gear box (and it's noise and complexity).

Click to expand...

I was wrong about the price.

Much much higher (something like 5x) .

I really like your idea of a Super 7 EV .

markobetti said:

I LIKE THAT MOTOR ! UP ON THE PICTURE HEY GUYS , ON APRIL 19 WE WILL HAVE ALL NEW MOTORS THAT HAL REDESIGNED : -HALL SENSORED , LIQUID COOLED (USE IT WITH OR WITHOUT IT ) . AND JUST TO TELL YA , HALL ALREADY MADE MOUNTS FOR CONNECTING 2 , 3 ,4 ,5 ... MOTORS TOGETHER AND A FEW MINOR CHANGES

Click to expand...

I'm definitely interested in 1 or 2 of these. Let us know how we can go about getting them ordered.

I'm certainly in for 1 if it's possible to convert this motor from DELTA to WYE (if it's wired in DELTA by default). My goal is to use this motor to power a paraglider prop of 48". Around 45kv would be ideal for this. Anyone knows if it's possible to convert any outrunner from delta to wye? And why are outrunners always factory wired into delta? Sorry for all the questions...I'm an e. engineer but pretty new to high powered BLDC's.

Looking forward to see the new motor design! Can't wait to get one

nertog said:

I'm certainly in for 1 if it's possible to convert this motor from DELTA to WYE (if it's wired in DELTA by default). My goal is to use this motor to power a paraglider prop of 48". Around 45kv would be ideal for this. Anyone knows if it's possible to convert any outrunner from delta to wye? And why are outrunners always factory wired into delta? Sorry for all the questions...I'm an e. engineer but pretty new to high powered BLDC's.

Looking forward to see the new motor design! Can't wait to get one

Click to expand...

Delta doesn't require connecting any wires, just bundle the 6 ends of the 3 wires together in the correct pairs, shrink wrap them together in a bundle, and call it a day.
Every RC delta motor can be turned into a wye motor. However, some wye motor's don't make proper delta-motors.

markobetti/hall: is this motor wired in delta or wye configuration?

I finally get out of the dungeon...
So, the motor design is finished. We are waiting for the prototypes. They should be here by the end of the month..
I made some modifications on the original motor. The dimensions will be the same but the shaft exits on other end.
splined exit shaft make it more expencive so it will probably have just a slot.
Also there will be hall sensors and KTY 83-122 thermistor build in.
The water cooling system is also included.
Some cooling data. minimum channel diameter is 28,3mm^2
minimum liquid contact area is >16000mm^2
motor is delta but it is no problem to leave all wires outside.
5 support bearings system with some Japan bearings. (We specialy asked for the best bearings they can find, also we asked for bearings manufactures certificate)
Don't know exit wire dia jet.

We have here two sayings that accurately display how I am feeling right now.
1. "Sitting on the nails..."
2. "too have worms in my B..t "

And the most important our goal is to have price under 300$

here are some dimensions.

http://www.greyb.org/collossus/dimenzije.pdf

That looks great.

Could the output shaft be longer, to allow a bearing on the end, beyond the hub/collar?

It is easier to cut off excess, than to add more shaft.

Just wondering...

why do you need more shaft , cant you se the extra part for shaft that hal made . That motor s going to be a rocket Hal i didnt visualise it like that. I now can see the original cover changed, now it looks evil enough to beat plletenberg 30 and just maybe with that cooling get to the power of 37 !! okay its bigger , but who cares it looks better

markobetti said:

why do you need more shaft , cant you se the extra part for shaft that hal made .

Click to expand...

The magenta part looks like a sprocket flange.

I'm suggesting enough shaft to support the shaft on both sides of the sprocket.

Great work guys, this is one of the most exciting things on ES at the moment, especially when you consider the possibility of joining multiple motors together. I'd love more info on how that'll be done Hal. Can't wait to see what creations this spawns!

I think the shaft can be longer, but AFAIK there is no need, it is 20 mm dia. It is made out of 1" steel rod. so It is no problem to make new one. the reason for big thread (M10) inside shaft is also that you can make aditional part of the shaft so you can conenct two motora with shafts to have single sprocket or you can make support bearing os you can connect to back of another motor with adaprer.
The magenta part is connection part for two motots. from one side it firs shaft and form another it fits rotor. Actualy it fits some bike sprockets but not all. You have to make motor support only. But I am drawing now interconecting part with additional support bearing( not because we need it, yet because i want to make part that connects barrels with shaft and also uses as support...

Marko, Hal,

Nice work.

Do you have the other motor parameters, such as winding resistance and max speed?
I think you said Kv=75, is that still correct?

Nick

Put me down for two of the sensored version please......

Tiberius said:

Marko, Hal,

Nice work.

Do you have the other motor parameters, such as winding resistance and max speed?
I think you said Kv=75, is that still correct?

Nick

Click to expand...

kv : 75 is correct , as we are aware

All data I will put by the end of the month. I hope so.
There will be only one version and you can use them at least on 6 different ways. sensorless, sensored, watercooled, naturalcooled, To know how hot it is or to not know. And of coure all combination of this...

That is fanatastic, great work Markobetti and HAL9000!

How is the water cooling done? Is there a tube in the valley of each slot below the windings?
Do the tubes terminate in a header/manifold? or is it one continuous tube?

Thanks for this effort, it's turning into a great motor!

Water cooling will be awesome!

These motors are getting better and better. Good work guys 8)

I'm thinking of getting 9. 8 for me, 1 for KiM.

-Luke