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Discussion Starter #1
I am fairly new to this EV thing... I am looking at bringing in some 10KW DC brushless hub motors from Hong Kong for testing purposes... They are rated at 48 to 300 V and 200A to 400A... They are equipped with a brake rotor and rim for 15 inch tires... Of course the price comes down with the total number but I am committed to 20 at $1000 each so if any one would be interested in a couple let me know... They would be FOB from Phoenix... I have dealt with the man I am using for this deal before and he has always been reliable... I am having him track down some more technical data so I will keep you updated... If there is something you want to know then ask me and I can get an answer...
 

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I am fairly new to this EV thing... I am looking at bringing in some 10KW DC brushless hub motors from Hong Kong for testing purposes... They are rated at 48 to 300 V and 200A to 400A... They are equipped with a brake rotor and rim for 15 inch tires... Of course the price comes down with the total number but I am committed to 20 at $1000 each so if any one would be interested in a couple let me know... They would be FOB from Phoenix... I have dealt with the man I am using for this deal before and he has always been reliable... I am having him track down some more technical data so I will keep you updated... If there is something you want to know then ask me and I can get an answer...
The technical data would be good, dimensional data and weight as well as more details on the power rating....is 10kw the continuous rating? what is the peak?
300V & 200A = 60kw peak seems like a lot for a brushless hub motor...
 

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Of course the price comes down with the total number but I am committed to 20 at $1000 each so if any one would be interested in a couple let me know... They would be FOB from Phoenix...
If they work at 48 Volts I might be interested in buying two. How much do they weigh? What kind of controller do you use with them? Feel free to send me an email to my hotmail account at johnatevw.
 

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Discussion Starter #4
yes at 300 V and 200A that is 60 Kw... My man tells me that the motor is 10 Kw constant and can handle 18 to 20 Kw for a short time... I am trying to get better info but with his engrish I am not sure how that is going to work out... As for controllers, I am going to use a home made one...
 

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I am fairly new to this EV thing... I am looking at bringing in some 10KW DC brushless hub motors from Hong Kong for testing purposes... They are rated at 48 to 300 V and 200A to 400A... They are equipped with a brake rotor and rim for 15 inch tires... Of course the price comes down with the total number but I am committed to 20 at $1000 each so if any one would be interested in a couple let me know... They would be FOB from Phoenix... I have dealt with the man I am using for this deal before and he has always been reliable... I am having him track down some more technical data so I will keep you updated... If there is something you want to know then ask me and I can get an answer...
You sound like a potential vendor. Generally a DIY builder would show us the motor and the supplier and ask our opinions, especially when 'new to this EV thing...'. You seem to be in the role of the 'go between'.

This thread may get moved to the vendor's forum.
 

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You sound like a potential vendor. Generally a DIY builder would show us the motor and the supplier and ask our opinions, especially when 'new to this EV thing...'. You seem to be in the role of the 'go between'.

This thread may get moved to the vendor's forum.
This also sounds very close to another vendor (Enertrac) offering of a 10kw cont. 30kw peak hub motor wired into a motorcycle rim...

Well he already mentioned he is committed to buying 20 units for 1000$ each and asked if anyone would want to buy them from him...So i would say this sounds like reselling...unless he has a huge garage! :p
 

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Discussion Starter #7
Sorry for not getting back to you all before, I do have work to do and was not in the US... Well as for reselling or from Enterac (who ever that is)... Neither is correct... My background is I used to design and build automatic assembly machines for wire processing equipment from concept to when I went and installed/trained the operators... You probably have some stuff in your house with electric wires and cords made on a machine I built... I am thinking of building my own EV from the ground up when I call it quits soon, so I am looking at getting the motors made (the idea of taking a shelf motor and modifying/adapting it makes no sense to me)... I did build a 3 speed automatic transmission to attach to a motor (kinda cool with a pushbutton override control)... I thought I would buy 20 to cover the setup cost... I thought it would be a good idea since this is not a motorcycle rim and that someone here would like a good deal... I thought that maybe someone here would be interested in them and was looking for ideas from the forum as to what voltages and speeds etc that would be helpful... If you want to call me a reseller, then so be it, but I have not decides what company to have build them (probably one of the companies I did business with in China or in Korea)... That is why I put a $1000 figure on them (that will not cover the cost of the setup with the import and shipping costs), but if not I figure I will just hold on to them (and yes I have a big garage with CNC mills, welders and lathes in it, a 100 foot by 60 foot pole barn if you need to know)... Same for the battery packs, either going to use one or 2 (not sure if I should go 96 or up to 300 volt)... I will probably build my own with LiPO4's and the BMS/Charger also and probably the regen drive to control 2 to 4 motors... I will probably build a onboard multi output generator to allow unlimited drive time using a LP or gas powered motor with fuel injection and to get good mileage I will probably have to build a single board computer system to control the engine and then control the rest of the cars functions (AC, power steering, vacumn pump, etc)... Might even put in a cute LCD display with a DVD so you can watch videos and wireless internet capable... So I guess I will just keep reading and figure it out on my own...
 

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Discussion Starter #9
Thanks for the thread, I should have stopped there on my way thru (just left Kuwait last week and was in Egypt about 3 months back)... I personally am not thinking that a gearmotor is the way to go.. I lost about 3 to 5% on my auto trans in power loss and my thinking is a direct drive brushless hub type (fixed stator) motor is a better deal... I have seen my share of broken connectors from overtorque in my lifetime... And built a few different motor drive systems and destroyed them... There is a servo motor manufacturer out of Boston that sent me all their new stuff to test (if I could not break it then it could not be broken)... So a 1200 RPM custom motor is probably the best... I am thinking that 10 to 15 KW continuous and then torque to maybe 30 to 50 KW for up to 1 minute should be enough... I am leaning at 144 V input but have not decided yet on the motor voltage (somewhere between 100V and 300V is what I am thinking), have not decided if AC or DC is the better way, depends on what my electronics guy says for the motor controller... Higher voltages always are better since the wires get smaller, but then you do have people that worry about the votages (maybe I could try one of the 225 KV transformers here on one LOL)... Also leaves the regen question and how to handle the extra power serge (I do not want to blow off the return power, but buffer it all back to the battery)... I have a friend that is high up at General Atomics (they build up to 1 megawatt wheel motor systems for 150 Ton dump trucks, etc)... So I might have an in on some of General Atomics high end self healing capacitors...
 

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Hi ScottBear,

If you are not intending to be a seller then I can move your thread back to motors. That is on the assumption that you are seeking advice and sharing knowledge and your findings as you develop an idea of the type of motor you want to use.

However, if you do decide to acquire a lot of motors and wish to sell some then you can post new threads in the classified or vendors section.
:)
 

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Discussion Starter #11
I just came here to see if I could get some input on voltages/amperages before getting some motors made... I picked 10 KW because that is a good number. The cost to do this will be paid by me... I guess this site is all about jumping on ideas... I will figure it out myself... Thanks
 

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We are interested in your intentions with regards to your EV and your motors, ScottBear, so I hope you are not taking this in a negative way. My apologies if you have.

I will move you back to the motors forum where, I hope you will find the responses to your queries.
 

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I just came here to see if I could get some input on voltages/amperages before getting some motors made... I picked 10 KW because that is a good number. The cost to do this will be paid by me... I guess this site is all about jumping on ideas... I will figure it out myself... Thanks
Hey ScottBear,

jumping on ideas
You mean Hub motor or wheel motor? Just about every month or so some new guy comes on here and either wants to know where he can get a wheel motor, or is going to make his own wheel motor, or is going to do something with wheel motors. This has been happening here for the past 3 years and in the industry for the past century. Nobody here jumped on your idea. We've heard the talk before.

Hello Mr. ScottBear,

Perhaps you can contact the gentleman who started this thread. http://www.diyelectriccar.com/forums/showthread.php?t=20591&highlight=wheelmotor

Good luck with your EV,

major
Did you take time to read that thread? I was politely trying to tell you that you are making a mistake to invest time and effort and money into wheel motors.

Up to you,

major
 

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I guess this site is all about jumping on ideas.
There are a lot of people on this site, and on the Internet in general, who like to jump on people's ideas. For some reason, the idea of hub motors in cars (as opposed to bicycles or scooters) seems to get some people hot under the collar.

Hub motors are not quite as bad as global warming for getting people going. But close.

Don't let it worry you. There are all kinds of people who look at this site. Some of us are interested in what you are planning. Please stay and share with us what you are doing.

As for me, I think hub motors -- one in each of the car's wheels -- may turn out to be the best design for the future of cars. But as Major says, people have thought that for as long as there have been cars. In fact, Ferdinand Porsche built a car with hub motors back in 1903.

I have been looking for some good hub motors for a couple of years. BluWav, now part of Magna, builds hub motors. But they do not sell to the public. That's why I am interested if you do get some motors built for yourself, and can help offer them to others. I am particularly interested in 48 Volt motors.

The admin here has to be careful about vendors posing as regular posters. Again, don't take anything negative from that. Stay and share.
 

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Discussion Starter #15
Daanii,

The idea of using a standard motor to move a car does not make sense to me... I have made a career out of thinking outside the box... And using a lot of motors to do a lot of things they were not designed to do... But in the end I found that building what I needed was the best way... I built machines and made my own air cylinders because the ones on the market would not stand up to the (what they called abuse) normal speeds they wanted...

To do what I want to do with a 'shelf style' motor would require a substantial amount of speed from the motor and couplers, transmissions, clutches, etc (ie. power loss)... Most shelf motors are built to not run over 2000 RPM and the ones like Warp that are, cost to much for what you get... So I am going to look into what I think would allow me the best deal for power loss and cost... Same thing I am finding with battery systems... Now as for 48V vs higher voltages... With a higher voltage you get away with smaller wires(cost), less heat/transmission loss(power)... While dealing with motors under 7.5 HP this is not a big deal, once you get to 15HP and up it does... Remember volts times amps equals watts (power)... And wire size determines amps, so to send out 30 KW at 48 volts takes 625 amps and need a 1000 gage wire to do it cleanly (and you still lose about .2% to the wire)... Now ramp that up to 300 volts (like the big boys do) and then you are down to a 2 gauge wire with the same .2% loss, much better deal... That is why I built my servo motors to run at 400V and 15 amps... Much smaller motor for the power... and if you make the motor so you can bolt an off the shelf rim and tire to it, then I think you can see why the big boys are heading that way...

 

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That all makes sense. Many of the carmakers seem to be doing as you say, and moving to higher voltages.

But I'm taking a different approach. I'm putting a motor at each wheel. (For now, the motors are connected to the chassis, so they are sprung weight, with a half shaft going to the wheel.) Each motor will be 48 Volts, with a 300 Amp controller. That's a maximum of about 15 kilowatts per motor, or about 60 kilowatts for the car.

Two main reasons for that design.

First, safety. Although not perfectly safe, 48 Volts is rarely lethal. Anything above 50 volts is much more dangerous. In fact, in the European Union, any electrical system in a car above 50 volts must be treated as a lethal system, with onerous safeguards.

Second, fewer battery cells are required. Generally you have to hook up battery cells in parallel to get voltage. For 300 Volts you need 6 times as many cells as for 48 Volts.

So our designs differ. I'm not sure which design is better than the other -- high voltage or low voltage. Maybe time will tell us.
 

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But I'm taking a different approach. I'm putting a motor at each wheel. (For now, the motors are connected to the chassis, so they are sprung weight, with a half shaft going to the wheel.)
This is what I would prefer to purchase, motors that are ready to slap a CV/halfshaft into. Preferably with a single-gear reduction built in.

In my book wheel motors are a bad idea to jump into.. the liability of making it DOT safe/approved, the variety of lug patterns and offsets to all the vehicles, brake clearance and heat issues, potholes, mud, unsprung weight.. the list is huge. Then consider how finicky people are with wheel looks.. and when was the last time you watched some kid at wallmart replace a tire. The only advantage I can see is the elimination of the halfshafts. That's not much, a part with virtually no power loss and only needs new boots+grease every 150k miles. Slightly more loss in CV's but easy to minimize in a situation where you have electric control of all 4 wheels.

Virtually all of the advantages of the layout still remain.. individual wheel control, no transmission weight/loss, etc...
 

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Discussion Starter #18
well what I was thinking is something like motor that allows you to bolt a standard car rim to it with a standard off the shelf the rotor mounted to the motor also... That way you have the look similar to most cars on the road today... Since all you need to make is a mount for the shaft and a way to attach the caliper it seems easier to me then making all the half shaft stuff, belts, chains, couplers, etc... And one thing I learned a long time ago with any machine is... The less moving parts the better...

As for the jarring from the road... Well if the bearings are done right and can carry the load then that is not a problem... I am thinking of using 2 inch tapered roller bearings (much like a standard car uses only bigger)... With epoxied magnets encased in the spinning hub (this takes a little machining to make a 2 pc hub to encase them)... I am also thinking of using rare earth magnets like I do in the high speed feed motors on the wire machines I built...

That leaves the windings... And if the windings are properly done, then that is also not a problem... You should see the abuse a vibration conveyor motor gets... It will run about 6000 hours a year with a 200 lb off center weight at 1750 RPM while bouncing violently up and down...

A direct drive motor also would run at a much lower speed... This means you can use a 215/70R15 tire and rim (about $700 for a nice set of 4) and only have to go about 900 RPM to get to 70 MPH (at 1750 RPM it would go 135 MPH)... This will also keep down on the high speed motor whine most home built vehicles have... By building the motor to go as fast as 1750 RPM this allows you to go down to a smaller rim/tire package (as low as 12 inch) and still get over 100 MPH while getting a lower the amp draw from the lower torque requirements...

I am still trying to get the working voltage for this project worked out... I am trying to weigh the cost of building a battery with a BMS/Charger system... These LIFEPO4 batteries are a pain to monitor and charge... SO I might go to multiple banks or maybe do a blended battery setup (NIMH cells from a Prius to act as a buffer) to allow continuous drive... See I can not build something that will only get me 20 to 60 miles down the road as today I had to go 255 miles round trip for a job...
 

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ah, yeah that seems not as bad. But you are limiting the max diameter available, key in low rpm high torque motors. would you have an integrated gear reduction? I know, more moving parts.. but really do you think you could start off with 600 ft-lbs directly without at least a 2:1? Something that size is good for a lot more than 1krpm.
 

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Discussion Starter #20
Well, with a proper controller you can get 100%+ torque at 1 RPM... Gears cost about 15% of your power to run... That also holds true for belt drives... I found this out when I built a machine that used a stepper system and according to the math (you know that the math does not lie LOL), that a 1800+ oz-in motor would work... But I decided to use a 900 oz-in motor to save money and a 2.5 to 1 drive... Well the math said it was ok... My lesson learned when I had to redesign 90% of the machine and cabinet to put in a much larger 1900 oz-in motor and then pay to fly the machine to Atlanta to make the ship date... So I will stick to direct drive...

By moving the magnets out farther to the outside of the rim you will lose less torque to the diameter for the wheel (I am leaning for a motor case of 10")... This means I have 10KW of power at a 5" radius and that is a lot of torque...

As for speed this is a simple equation that tells the motor mfg how many turns and poles to make the motor (here is that equation RPM = (120* Frequency) / # of Poles)... The wire size will determine the amount of amperage that you can send to the windings and the hertz will decide the speed... And yes I am leaning towards a 6 pole three phase AC motor (gets me 1200 RPM at 60 Hz) over a DC motor... Have not decided on a running voltage yet...

AC drives give much better low speed than a PWM drive for smoother running at lower speeds, plus I could go higher than 60Hz if I wanted... I think most people believe DC is safer or easier than AC... Only difference is in what it does to the muscles when if you come in contact with it... Either way once you pass about 48 volts you don't want to touch either...
 
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