R Martin EVD Moped with HubMonster

fechter said:
6.5v on the lead battery isn't a good sign. Time to recycle.

A 50Ahr lithium battery will probably give about twice the range as a 50Ahr lead acid battery. Less weight combined with less Peukert effect.

Just for reference, here's the dimensions of a Nissan Leaf battery module. These are 2s each, rated for 64Ahr. For 16s, you would need 8 of them. Chevy Volt batteries are fairly easy to find too.

Nissan Leaf Battery Module.jpg

Yes...thanks...been looking at them on ebay.
 
macribs said:
Great find. Should be a nice sprint around town vehicle.

Sprint around town...LOL...I intend to commute 50 miles each way on it and top out at 90+ so that I can use it on the interstate.
 
Ok, let us know how that goes.

For such a long commute I think me personally would prefer ICE motorcycle, or a BEV car. Kudos to you for sticking to your guns.
 
macribs said:
Ok, let us know how that goes.

For such a long commute I think me personally would prefer ICE motorcycle, or a BEV car. Kudos to you for sticking to your guns.

I already drive an ICE car into work every day. I'd rather do the trip all electric if possible.
 
You'll probably need to do ventilated cooling with exterior blades to run that kind of commute carrying the amount of battery you'll need. The approach I use works incredibly well. A cooler motor is a more efficient motor, and you can run higher power, which increases the fun factor.

Too bad the laws where you are aren't the same as here. I love teaching motos a lesson about how much better electrics are. After slaughtering them from the stop lights I explain that my fuel costs for the year are what they pay just in registration and inspection fees, and how maintenance and repairs is just remembering to connect the charger and keep air in the tires, then saving the planet is icing on the cake along with other intangibles like no gears to constantly shift through in traffic and near silent operation.

Aerodynamics are a huge factor at highway speeds, so it will be interesting see how the existing plastic works, but you might need to lower the seat and narrow the width so you're punching a smaller hole through the air. I saw a video the other day of some pretty cool tricked out scooters that might give you some mod ideas. I'll try to find it again and send you a link.
 
John in CR said:
You'll probably need to do ventilated cooling with exterior blades to run that kind of commute carrying the amount of battery you'll need. The approach I use works incredibly well. A cooler motor is a more efficient motor, and you can run higher power, which increases the fun factor.

Too bad the laws where you are aren't the same as here. I love teaching motos a lesson about how much better electrics are. After slaughtering them from the stop lights I explain that my fuel costs for the year are what they pay just in registration and inspection fees, and how maintenance and repairs is just remembering to connect the charger and keep air in the tires, then saving the planet is icing on the cake along with other intangibles like no gears to constantly shift through in traffic and near silent operation.

Aerodynamics are a huge factor at highway speeds, so it will be interesting see how the existing plastic works, but you might need to lower the seat and narrow the width so you're punching a smaller hole through the air. I saw a video the other day of some pretty cool tricked out scooters that might give you some mod ideas. I'll try to find it again and send you a link.

Thanks John! There will be challenges to overcome. I think the entire plastic set will come off just to lose weight and then I can pretty much do whatever I want after that. I'm fine with it being stripped down a lot and there's options that will make the frame look less bare.

What do you think about this motor? It looks like a smaller version to the hub monster. You mentioned a 3kw version. Is this it?

Pantera%20hub%20motor%205.jpg

Pantera%20hub%20motor%204.jpg

Pantera%20hub%20motor%202.jpg

Pantera%20hub%20motor%201.jpg
 
fechter said:
Wow, how wide is that stator? I think you'll have to work at it to overheat that thing.

Good question...50mm or so. THe stators in it are really nicely made. I'm torn about selling off the motor in the moped I got it in.
 
The one on the left is a HubMonster. The latest one open with the high slot count definitely is not, and definitely not a motor for high speed. MidMonsters share the same design as HubMonster (slot/pole counts) and same high quality Japanese motor steel. That combination is what makes them capable of so much high peed than high slot/pole count motors, and it's what gives them so much higher efficiency. MidMonster is about 30% smaller and it's magnet ring is cast in an aluminum sheel.

High slot/pole motors are more common because they are cheaper to make for the same torque capacity, because the motor steel doesn't have to extend as far to the center. The tradeoff is more alternating polarity switches per revolution, so more heat from iron losses for the same rpm.

The 6 phase of the Monster family designs has the following benefits:
- More turns on each tooth for the same rpm, so higher inductance for same Kv |(easier on controllers.
- Current split between 2 controllers, so much much cheaper controllers can be used, less than half the cost for the same power.
- Takeoffs are smoother, so they work just fine and near silent with cheap trap controllers.

Hope that info helps settle things a bit.
 
John in CR said:
The one on the left is a HubMonster. The latest one open with the high slot count definitely is not, and definitely not a motor for high speed. MidMonsters share the same design as HubMonster (slot/pole counts) and same high quality Japanese motor steel. That combination is what makes them capable of so much high peed than high slot/pole count motors, and it's what gives them so much higher efficiency. MidMonster is about 30% smaller and it's magnet ring is cast in an aluminum sheel.

High slot/pole motors are more common because they are cheaper to make for the same torque capacity, because the motor steel doesn't have to extend as far to the center. The tradeoff is more alternating polarity switches per revolution, so more heat from iron losses for the same rpm.

The 6 phase of the Monster family designs has the following benefits:
- More turns on each tooth for the same rpm, so higher inductance for same Kv |(easier on controllers.
- Current split between 2 controllers, so much much cheaper controllers can be used, less than half the cost for the same power.
- Takeoffs are smoother, so they work just fine and near silent with cheap trap controllers.

Hope that info helps settle things a bit.

John,
Thanks for all the good info!

It looks like the hubmonster so I thought it was one of the midmonsters since the shell looks so similar. It has really nice stators in it. They are better than any hub I've ever opened up.

If you have 2 motors on the same stator doesn't that effectively halve the number of transitions per motor? Why not take any high tooth count hub and rewind it as 2 motors?

This ought to work on any motor. I have an Alien Power 12090 outrunner. It has 24 stators in it. If I rewound it as 2 12 stator motors, the eRPM would be 1/2 as much per motor. I would have half as many transitions per motor per rotation right? The pole count per motor would be half of the total pole count. It's wound for 50kv right now. Getting an 18kw controller that runs at 100 volts and can keep up with the motor is a limiting factor. At 100 volts it's eRPM is 60,000. Rewinding it as 2 50kv motors would require 2 9kw controllers, but it's eRPM would be 30,000 at 100 volts. Maybe there's not enough iron here to make this work well? Am I getting the implications right?

Halls%20board_zpsirvvvmgo.jpg


Look at the magnets in this motor. Look at how big the stator is. I bet it has 30% more iron per tooth than the QS motor in the bottom picture. The magnets span 3 stator teeth. Doesn't that make this actually a low tooth count hub? I have no idea how it's wound. Typically 3 side by side teeth are the same phase with the center tooth wound backwards of the outer 2 teeth and the magnets are the same size as the teeth. How does that work on a single magnet with the center tooth wound reverse of the outer 2 teeth? I think it doesn't work at all and is immensely wasteful if done. Maybe all 3 teeth are wound the same direction so they can all present the same magnetic pole to the magnet? If that's the case, then this is a 3 phase, low tooth count motor right now. It has 48 stator teeth and 16 magnets. It has to be wound with 3 side by side teeth in the same phase and all wound the same direction.

Pantera%20hub%20motor%202.jpg


It can be done, but why would anyone ever do this in a motor? A single magnet can be made with 3 magnetic domains in it. By why not just make 3 smaller magnets instead and place them side by side like in the below QSmotor? It is more logical that the magnets in this motor are a single magnetic domain. The inner face is a single north pole or a single south pole, not north/south/north on a single magnet face. That, IMHO, would be the only way to make a reverse wound center stator tooth work with a magnet that spans 3 teeth.

This is a multi-domain magnet. Each section on the film is the opposite pole. you are seeing 4 north and 4 south poles here. Hard drive magnets do this too. The magnet is actually 2 side by side magnets with the poles flipped. I was really surprised by a lot of magnets when I got this magnet film!

multi-domain%20magnet%202.jpg

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This is a 4kw QSmotor I have. This clearly has 1 magnet width per stator tooth. What you said about hi tooth count stators totally applies to this motor.

Motor%20internals%209_zpsyxamkdpa.jpg
 
20 magnets of alternating polarity whizzing by 24 stator teeth is the same frequency regardless how it's wound. Pole count is based on magnets, not the stator. If your Alien motor has 20 magnets, then yes it will work fine wound with 6 sets of phases. If the magnetic pole count is different, then it would have to be modeled first. In HubMonster's case 12 are wound as one 3 phase motor and the other 12 the other 3 phase motor using alternating teeth. The only negative of winding this way (other than the practical problem of dual controllers on one throttle), is that it makes some of the end windings longer. That negative impact on efficiency is negligible, since no other production hubmotor has come close to its 95% peak efficiency.

FWIW, your Alien motor would definitely be easier to drive wound as a 6 phase. I remember one guy years ago with a big DIY motor. He ran it both as a 3 phase and as 18 phase, and he reported it running much more powerfully and smooth when terminate to use 6 tiny cheap RC controllers than it did with a big 3 phase scooter controller.
 
John in CR said:
20 magnets of alternating polarity whizzing by 24 stator teeth is the same frequency regardless how it's wound. Pole count is based on magnets, not the stator. If your Alien motor has 20 magnets, then yes it will work fine wound with 6 sets of phases. If the magnetic pole count is different, then it would have to be modeled first. In HubMonster's case 12 are wound as one 3 phase motor and the other 12 the other 3 phase motor using alternating teeth. The only negative of winding this way (other than the practical problem of dual controllers on one throttle), is that it makes some of the end windings longer. That negative impact on efficiency is negligible, since no other production hubmotor has come close to its 95% peak efficiency.

FWIW, your Alien motor would definitely be easier to drive wound as a 6 phase. I remember one guy years ago with a big DIY motor. He ran it both as a 3 phase and as 18 phase, and he reported it running much more powerfully and smooth when terminate to use 6 tiny cheap RC controllers than it did with a big 3 phase scooter controller.

I know how pole count works. But a dual wound motor is only seeing half of those magnets at any point in time. A single wound motor sees all of them at the same time...well 66% of them technically. The speed of the magnets going by hasn't changed and the total number hasn't, just how many any 3 sets of of windings sees at any point in time. Isn't that the same thing as halving the pole count?

In my smaller hub, the magnets span 3 stator teeth. If 3 teeth are wound as if they are a single tooth, then they aren't electrically 3 teeth anymore. 3 side by side winds all in the same direction is effectively a single tooth.

If you run across any threads on doing dual or tripple winds, please post them here. You've opened my mind up to new possibilities that I have to go explore. I think my 12090 is going to get a rewind. It can take a lot more copper per tooth. I might as well get it running at 22kw or more dual wound.

GAWD...I thought 6 phases was a lot and now you tell me 18 phase!!! That is one crazy motor set up! How did he know the motor ran better at 18 phases? Did he somehow connect together phases to make it into a 3 phase motor? That wouldn't be hard really, but I think many more winding in series would increase the resistance a lot. OR do it in parallel? My brain hurts right now. Geez..18 phases!
 
I just googled for 6 phase, 9 phase, 12 phase and so on motor and found a single video. Maybe google is failing me...don't know, but I was hoping for a just a bit more than this!

In the video the guy shows current draw, voltage and motor RPM and I can't say 3 phase vs 6 phase was a game changer on his turnigy 80-100.

https://www.youtube.com/watch?v=LgRK4_4ElhU
 
The number of phases is no game changer, though I suspect as you add more controller MCUs hunting for the rotor position that the startup under load becomes smoother, maybe even enough so that sensorless operation becomes practical at useful power. In terms of the motor itself there is no difference, because it's the same magnetic forces working at the same radius.
 
John in CR said:
The number of phases is no game changer, though I suspect as you add more controller MCUs hunting for the rotor position that the startup under load becomes smoother, maybe even enough so that sensorless operation becomes practical at useful power. In terms of the motor itself there is no difference, because it's the same magnetic forces working at the same radius.

The video was under no load. It's not a real test. I wonder what loaded is like? THat's the real test.
 
John in CR said:
FWIW, your Alien motor would definitely be easier to drive wound as a 6 phase. I remember one guy years ago with a big DIY motor. He ran it both as a 3 phase and as 18 phase, and he reported it running much more powerfully and smooth when terminate to use 6 tiny cheap RC controllers than it did with a big 3 phase scooter controller.

And here I have been dreaming of lightweight RC style 6 phase motor, to double up on the RC ESC. I can't even dream big enough. Now an 18 phase custom motor powered by 6 ESC surely would put less strain on each ESC. But this got to stop somewhere? I mean efficiencies can't keep getting better the more 3 phase motors stuffed into one casing? Because then a 36 phase motor with 12 ESC's would be even smoother and each controller would work even less hard.

I remember reading that the famous Joby motors could be had in 6 phase, or any other custom winding. Now I've only seen one bike here on ES using joby motor, and even without custom winding that little devil outrun 250 cc dirtbikes on an oval dirt track, and 450 cc on a tighter enduro style track. Would the added costs of a custom winding for what is a high priced motor in first place, be rewarded? I mean what really sets the limit in the end? The motor or the controller?

Astro got the popular 3xxx series motors. The 3220 claimed to do 12-14 kw peak for a second or two. Probably not much more power to collect there from the motor? Maybe a custom 2 x3 phase could give the ESC more longevity and less strain, and help with less heat on the wires etc. Astro even got that crazy long 4xxx motor, probably capable of close to 30 kw or even a little more for brief second or three. But afaik there ain't no esc available to handle such a motor. Well at least not within the financial reach for hobby DIY'ers. Then they have a secret motor 3230 that is just too powerful for esc's like Hv 160. Maybe such a motor could do with a custom winding. That secret motor is not even listed, but will be made upon request I was told. But they couldn't recommend any ESC to use with it. And they won't do custom winding job either.

Puh long intro. What I am getting at is that for hi spinning motors like RC motors and the like there are limits both in motor power and how much power the esc's can put out. Some motors are so well build that they could probably be surprisingly stable at high power. But we don't got esc's to explore past the already crazy power outputs people like Matt and others already done. To see the maximum limits for such motors 6 phase would be great, why don't motor manufacturers make small batches 6 phase motors to have e-bikers test the crap out of their limits?

There are a handful of motors that could be good candidates for 6 phase, but I don't see it happen as the manufacturer will not make em. So the alternatives are bulky hubs, heavier and larger mid motors made for motorcycles or the only sane option to use multi motor setup for power more then 12-14 kw peak. Think we will ever see a ready to purchase 6 phase single motor setup using dual esc and pushing 20 kw + in a small form factor package RC motor, neematic diy style?
 
On the subject of alien motors...John has opened a can of worms for me that can't be re-canned...not until I go nuts.

I found a 12090 with damaged windings. It's brand new except for the damaged wires. No broken magnets and 100% mechanically sound. I'm going to see about grabbing it and then triple wind it. 9 phases with maximum fill on each tooth should be VERY interesting! From AP it's supposedly an 18kw motor at 3 phases. What will it do on 9 phases? Can I run 3 18 fet controllers and each is delivering 8 or 9kw? The magnets are something like N40's. After a triple wind, I think N50's are needed. No point in wasting torque on weak magnets! With all that investment, ceramic bearings are viable.

Introducing the worlds most expensive 12090 outrunner...a mere $1100 to build, but it can deliver 52kw burst and 45kw continuous. LOL...we will see! THat's doable with 3 24 fet controllers.

There has to be a limit where complexity and multiples of duplicate systems outweighs the benefits of having them. A 12090 could be wound with 8 sets of windings since it has 24 stator teeth, but would it be significantly better than 3 sets of windings? Would it be 3% or 5% better? Would the only advantage be the many smaller controllers? When do the inherent losses in the controllers add up to more than the gains in the motor?

A 3220 at 12kw? That seems very unlikely and enormously inefficient. Yeah sure you can dump the current into it, but did the motor pull any harder? I seriously doubt much beyond 7kw matters and is just heat.
 
The more I think about it, the more I think it was a 24 phase motor with 24 coils, ie essentially 1 tooth per phase.

There's no efficiency gain by going 6 phase. I outlined the advantages above. The Monster family of hubmotors have high efficiency due to thin high quality laminations, great copper fill with thick copper all the way to the outside of the motor, and a low slot and pole count. The 6 phase arrangement may pick up some efficiency through reduced torque ripple, but that's just speculation on my part based on the fact that they're more quiet than common hubbies when using trapezoid wave controllers.
 
Random thought... if you took one of those hub motors that bolted to the rim, and instead bolted a chainring on it... would it be a good choice for a gokart motor?
I mean you could gear it up or down a bit to match the wheel size... although 1:1 is probably about right since you want good acceleration but not extreme speed...
 
John in CR said:
The more I think about it, the more I think it was a 24 phase motor with 24 coils, ie essentially 1 tooth per phase.

There's no efficiency gain by going 6 phase. I outlined the advantages above. The Monster family of hubmotors have high efficiency due to thin high quality laminations, great copper fill with thick copper all the way to the outside of the motor, and a low slot and pole count. The 6 phase arrangement may pick up some efficiency through reduced torque ripple, but that's just speculation on my part based on the fact that they're more quiet than common hubbies when using trapezoid wave controllers.

I'd say the lams in an alien motor are of similar quality as the hubmonster. I can't be dead sure of that, but they look pretty much the same thickness. Rewinding would add a good bit of copper per tooth. These things are not overly full. So while it's getting rewound to maximize the copper, wind it for 3 phases at the same time. Obviously the 12090 won't have a low tooth count.

Halls%20board_zpsirvvvmgo.jpg
 
MrDude_1 said:
Random thought... if you took one of those hub motors that bolted to the rim, and instead bolted a chainring on it... would it be a good choice for a gokart motor?
I mean you could gear it up or down a bit to match the wheel size... although 1:1 is probably about right since you want good acceleration but not extreme speed...

The chain ring would be quite large if you bolted it to the flange that holds the rim. You would do better to bolt a sprocket to the brake rotor bolt holes. Otherwise the sprocket on the motor would be really large. you would need to gear it down significantly to get the motor RPM to match the wheel RPM's you want. I guess probably 2 stages of down gearing would do it, but why bother.
 
ElectricGod said:
After a triple wind, I think N50's are needed. No point in wasting torque on weak magnets! With all that investment, ceramic bearings are viable.

Stronger magnets will increase the kV (slower motor). The main thing is N50 magnets are generally not rated for high temperature.
The suffix letter tells you the temp rating. H rated (120C) or SH (150C) might be better for a high power motor. I think N45 is about the most you can get in a H rated.
 
fechter said:
ElectricGod said:
After a triple wind, I think N50's are needed. No point in wasting torque on weak magnets! With all that investment, ceramic bearings are viable.

Stronger magnets will increase the kV (slower motor). The main thing is N50 magnets are generally not rated for high temperature.
The suffix letter tells you the temp rating. H rated (120C) or SH (150C) might be better for a high power motor. I think N45 is about the most you can get in a H rated.

Thanks for that. I've wondered about the N or H before and thought it was a typo.
 
FWIW, you wouldn't drive from the bolt flange for the rim. Just use the disc brake mount for the sprocket. That's how I'll use one for the off road moto I want. Of course there's a 2wd one planned too, but that will be with them in-wheel of course. I need to get EG's help on controller for that one though...maybe we can work a trade.
 
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