# What drive train, 3 options



## Ioku (Sep 27, 2007)

I am looking for you opinions as to what would be the best drive system for the performance and abilities I am looking to get in an EV. You can also read my thread, EV Rally Car, here http://www.diyelectriccar.com/forums/showthread.php/ev-rally-car-5172.html to get an idea of what I a trying to do. 
What I want out of my EV listed in order 
1. Acceleration, I would like to get around 0-60 in 4 sec, or less
2. Handling, I want the car to handle as well if not better than the ICE version.
3. Range, I would like to get about 100 mile under normal diving conditions.
4. Top speed, This isn’t that big of a concern but I would like around 100 mph.

And the car I plan on using will be a 95 Subaru Impreza it is a popular Rally car and I already own one, you can also go here, http://www.proev.com/ to see an already converted 95 Impreza.

Option 1, single motor

In this option I would use I single AC motor connected to the Subaru AWD drive train which would include a 6 speed transmission. 
Benefits in my opinion, good acceleration this gear box is already geared for it, having a 6th gear could help with range on the highway and allow a good top speed, handling about the same as ICE, easy of conversion. 
Negatives in my opinion, this would mean more moving parts more things to break.










Option 2, Duel motors 

In this option I would use 2 AC motors, each one powering its own set of wheels, basically the same as the proev rally car. Benefits in my opinion, better AWD handling and better control of what wheels the power is going to, less moving parts less to beak down. 
Negatives in my opinion, possibly less acceleration and lower top speed being locked into one gear, range may also take a hit, more difficult to convert. 










Option 4 Quad motors

I this option I would use 4 AC motors each one connected to its own axle, I would do this instead of wheel hub motors to reduce un sprung weight. Benefits in my opinion, possibly the ultimate in AWD handling and control, It could even allow tank like turning abilities by running the right side motors clock wise and the right side counter clock wise it could literally spin on a dime. 
Negatives in my opinion, again being locked into a single gear could hurt acceleration, top speed and range, much more difficult to convert. 










And on a side note as I use more motors the smaller they would be, so I am not thinking of trying to cram 4 full sized motors in the car.


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## Mastiff (Jan 11, 2008)

I'd say go with the Single Motor attached to the standard transmission this has the advantages of:
1: MUCH simpler to convert the vehicle
2: You can get VERY powerful VERY efficient single AC motors
3: This retains the same 4 wheel drive handling as the original car
4: This can save on weight because more motors also means more controllers, motors + controllers = weight.
5: This will save on energy.
6: You'll have much better control over what kind of torque and RPMs are on your wheels with the Transmission still attached.

I wouldn't worry about parts breaking unless the 95 Subaru Impreza is prone to breaking, which I don't think it is.

Plus any customized system you have to design will have tons of failure points too, but these failure points are custom, thus YOU will have to fix them or build new parts for them.


If you want serious performance out of one motor I'd buy the "Heavy Vehicle Manual Transmission" kit from Electro Automotive:
http://www.electroauto.com/catalog/ackits.shtml#heavy

They are the only ones I know of that sell that Motor and controller.
It's the one I'd use in my dream EV:
http://www.diyelectriccar.com/forums/showthread.php/my-dream-ev-7747.html


This Pickup EV weighs *5,400* pounds and is powered by one of those motors:
http://www.evalbum.com/1430

It still reaches 70mph to give you an idea of the power of this motor/controller system.(it was designed for electric city buses)

Now your 0-60 time will be more dependent on the weight and C rate of the batteries you use, the ProEV Imp used Kokam Lithium Polymer batteries.

If you can use a battery pack of some Lithium Iron Phosphate batteries, they have a MUCH higher stable C rate, meaning if you had 200AH of power in your batteries you can actually draw x2, x3 or 4 times that power, depending on some packs.

You can try contacting http://www.lionev.com/ for a battery pack, I'm not sure of anyone else who sells lithium battery packs for EV's.


Just my $0.02.


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## Coley (Jul 26, 2007)

Your target is, at this time, not too realistic with the batteries we have at our disposal.

More drive axles, motors and such will cut the range and accel.

Unless you have an unlimited budget for the car, you may have to go a little less fast and not so far in distance.

But that is just my opine.....


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## Ioku (Sep 27, 2007)

Thanks for the links and advice Mastiff, I was also thinking that a single motor would be best from what I have read, but wanted to see what others thought of the more wild Ideas. And as for batteries I'm just going to wait before I decide on any because of how fast the technology is changing.


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## Mastiff (Jan 11, 2008)

Ah I remembered Valence (http://www.valence.com/), here's a topic discussing them:
http://www.evdl.org/archive/index.html#nabble-td15120633

Here's a list of EV's built with Valence batteries:
http://www.evalbum.com/battb/VALN

The Solectria Sunrise was built with Valence batteries.
I'm not sure if they're well suited for performance EV's but it seems like they sell a full battery pack and BMS and since other people have made EV's with them you know you can get your hands on them.


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## david85 (Nov 12, 2007)

I would recomend sticking with the motor that they already used on the proEV race car. The Azure Dynamics motor that electro carries is not very effiecient for an AC motor (none of them are in fact). With the controller at a mere 83% effecient (according to electro's specs) you would be better off with a DC brushed motor. The AC55 motor is also air cooled wich kills some potetnial horse power potential. Azure does carry an AC90 motor, that is in the low 90s for overal efficiency, but its a real pig for size and wight. They do design their motors for HD application, but the power to weight ratio make it more sutable for shuttle busses and other low speed vehicles that don't have to go very fast.

The siemens 5134WS20 AC motor on the other hand is available with a 98% effiency controller (brusa), with the motor itself being a little over 90%. And since its water cooled the continuous rating will be higher.


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## MitchJi (Dec 14, 2007)

Hi,

This Volvo uses 4 motors:
http://www.pmlflightlink.com/news_volvo.html

There was a recent interview on Autoblogreen in which a Volvo Executive said one thing holding them back was the difficulty of controlling 4 motors. So I think you might be better off with a simpler (single motor) system.

Mitch


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## MitchJi (Dec 14, 2007)

david85 said:


> The siemens 5134WS20 AC motor on the other hand is available with a 98% effiency controller (brusa), with the motor itself being a little over 90%. And since its water cooled the continuous rating will be higher.


Hi,

It also costs almost twice as much.

Mitch


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## Mastiff (Jan 11, 2008)

Here's the PDF spec from Azure Dynamics on the AC55:
http://www.azuredynamics.com/pdf/AC55+DMOC445 - June 2007.pdf

Continuous Torque* at Nominal Speed: 140Nm
Nominal Speed: 2000rpm

Peak Torque: 280Nm 

It's peak Torque lasts up until 2000Rpm then drops off the PDF shows.

I figured I should give you some real specs on the motor system since Electro Automotive's table isn't very complex.


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## Ioku (Sep 27, 2007)

The motor I was thinking of using is Siemens 1PV5135WS28 it can be found here http://www.metricmind.com/index1.htm and can do  [email protected] and has a top rpm of 10,000 it is a lot like the one the prove guys used only it looks more powerful.


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## Mastiff (Jan 11, 2008)

Wow, that motor is "Rated" at 650 Volts and maxes out at 900 Volts.

I doubt you could string enough lead-acids together to get that voltage without running into weight issues.

Here's the PDF on the Kokam batteries ProEV used:
http://www.proev.com/Graphics/DwnLoads/KkmData/PL-302_SLPB80460330H_100Ah_Grade.pdf

Those batteries retail at $1.60 per per watt-hour $592 per battery pack.
That's what the website says.


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## Ioku (Sep 27, 2007)

Yeah I don't have any plans of using lead battery's for this car it will be a few years before I will need to start looking for them so I am hoping by then some new cheaper more powerful battery will be available.


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## MitchJi (Dec 14, 2007)

Ioku said:


> The motor I was thinking of using is Siemens 1PV5135WS28 it can do  [email protected] and has a top rpm of 10,000 it is a lot like the one the prove guys used only it looks more powerful.


Hi,

If you get the price for the motor and controller would you please post them in this thread?

Thanks!

Mitch


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## david85 (Nov 12, 2007)

Some one else recently did a toyota pickup conversion with this motor, he stated that with everything needed for the system, it was in the $10 000 range.

Getting high voltage is not a problem if you have the money to have a custom LiPo battery made up. LiPos come in many shapes and sizes and allow for MUCH more flexibility of operation. The high voltage is one reason why the Siemens motor is more efficient.

As for the Wheel motor that was used in the volvo concept.....

We asked PML flightlink about their HiPa drive and long story short, it would have worked out to almost $100 000 for a 4wd turnkey system. I have learned form other sources (which may or may not be reliable) that the motors are a 92% efficient, not bad, but not great either.

In addition, the vehicle gradability was also limited to 14%, not good enough in my opinion.

A really interesting feature of the HiPa drive is that the motors REPLACE the braking system alltogether, so no more hydraulic braks at all, and the motors have a built in parking brake.

At the moment there are nearly a dozen companies world wide that have a working wheel motor concept, but none of them are in reach of mortals like us, I'm afraid....


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## MitchJi (Dec 14, 2007)

david85 said:


> As for the Wheel motor that was used in the volvo concept.....
> 
> We asked PML flightlink about their HiPa drive and long story short, it would have worked out to almost $100 000 for a 4wd turnkey system. I have learned form other sources (which may or may not be reliable) that the motors are a 92% efficient, not bad, but not great either.
> 
> In addition, the vehicle gradability was also limited to 14%, not good enough in my opinion.


Hi,

I did not suggest that he use either in wheel motors or in wheel motors from PML Flight Link. Just the opposite, I mentioned the Volvo Concept and suggested that if Volvo is having difficulty getting four motors to work together it might be a good idea to choose a single motor.

Mitch


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## spolkyc (May 15, 2008)

This question has many involved parts to think about. Another major part I have not seen anyone mention is weight distribution. There is a reason most cars put the engine up front. This gets kinda involved, but there is lots of dynamics of mass (engine and body) moving around and being driven by specific wheels and directed by other wheels.

But in general for dirt, mud, ice put it in the front. On asphalt mid engine is good. There are some good basic books on race car dynamics you may to look them over for some ideas.


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## FreedomVoltage (Jun 28, 2009)

well actually you are looking for something more along the lines of Plasma boy raceing, they use a custom built 8" Siamese motor with a zilla controller, and a battery pack from A123 systems, courtesy of the A123 racing team killa cycle the electric drag bike. here is the specs
__________________________________________________________
Base Vehicle: 1972 Datsun 1200 coupe Motor: 'Siamese 8' Dual armature series-wound. What used to be two separate 8 inch electric motors, is now one custom built motor that's 25 lbs. lighter, 7 inches shorter, and more powerful. Thanks to 'Hi Torque Electric' and 'Dutchman Motorsports'. Drivetrain: Direct drive (no transmission, clutch, or flywheel). Electric reverse. Custom aluminum driveline by 'Inland Empire Drivelines', 'Dutchman Motorsports' heavy duty 'Street Strip' rear setup with Dutchman 31 spline racing axles, Aluminum 'Strange' Ford nine inch differential with Detroit Locker, lead acid version uses 'Richmond Gear' ring and pinion @ 4:11 ratio, lithium ion version uses 'Strange' ring and pinion @ 3:70 ratio, custom made traction bars. Thanks to Dutchman Motorsports and Inland Empire Drivelines for their support. Controller: 2000 amp Zilla by 'Cafe Electric' with programmable series/parallel motor section switcher; ...launches at full torque (772 ft. lbs.) with motor sections configured in series mode, switched over at higher speeds to parallel for maximum horsepower. Thanks to Cafe Electric for their support.  Batteries: (lead acid version) 60 'Enersys' brand 16 ah' Genesis' deep cycle 14+ lb. AGM batteries for a total pack weight of 844 lbs....Thanks to Enersys, Aerobatteries, and Hawker for their support. (lithium ion version) 880 lithium iron nanophosfate cells for a total pack weight of just 175 lbs...Thanks to A123 Systems and the Killacycle racing team for their support.  System Voltage: 360 Volts (lead acid version) 374 Volts (lithium ion version) Charger: Manzanita Micro PFC 75, Rudman Regulators. At PIR (Portland International Raceway) where the Zombie usually does its thing, we get to plug into the 240V mains and charge air polution-free as the juice comes from Oregon's mighty Columbia River and its massive hydroelectric system. Away from home at other drag tracks where clean AC line power may not be available, a gasoline fueled 18 hp 2 cylinder Subaru generator makes 10 KW to feed the PFC75 and keep White Zombie's pack charged up. Thanks to Manzanita Micro for their support.  Heater: none (*The tires get pretty hot and smoke a lot!*) DC/DC Converter: Vicor based custom unit able to operate with input voltages up to 450V and able to output 14+V @ 40 amps. A 16 ahr 'Hawker Genesis' 12 volt AGM serves as a battery backup for the 12V system. Instrumentation: a) EVision battery computer. Thanks to Metric Mind for their support. 
b) 1000 amp E-meter Top Speed: unknown Range: At least a quarter mile! Seating Capacity: Driver and one passenger...rubber underpants required! Curb Weight: (lead acid version w/6 point roll bar installed)~2652 pounds. (lithium ion version)~1858 pounds. Tires: Rear....BF Goodrich DOT approved, 215/60/14 'G Force T/A Drag Radials' on Ford 5 bolt, 14 X 6 five spoke Eagle polished alloys  
Front...Nitto DOT approved, 175/50/13 'Exit GS' on Nissan 4 bolt, 13 X 5.5 five spoke Eagle polished alloys Additional Features: Electric line lock, 4/0 wiring, 3000 amp Kilovac Bubba main contactor, 240+ horsepower w/ 772 ft. lbs. torque (equivalent to ~350 hp gas) 
Custom metal fab work by Marko Mongillo. Thanks to Northwest handling Systems for the use of their forklift service truck as our trackside base support vehicle. 
 
(the following was written in 2006...check out how close the predicted performance came to the below highlighted actual results from the 2007 racing season!) 

 An all new battery pack is being readied for the 2007 racing season based on 60, 16 ahr Hawker Genesis batteries. This 360V pack will be 40% more powerful than the previous 360V pack, and will be capable of making 450 hp! The new pack will be 75 lbs. heavier, but the battery compartments will be far lighter, and other weight reducing mods should keep the car's curb weight close to the same. We expect ETs of 11.8 @ 110 mph, but with continued work, it's possible to see mid 11s for '07!
*Best lead acid powered ET 11.882 @ 109.58 mph!* 
*World's 2nd Quickest & Fastest* 
*'Street Legal Electric Door Slammer'* 
*(in the standing start NHRA timed 1/4 mile, per NEDRA)* 
*0-60 in ~ 3.5 seconds! *
*Best lithium ion powered ET 11.466 @ 114.08 mph!* 
*World's 2nd Quickest & Fastest* 
*'Street Legal Electric Door Slammer'* 
*(in the standing start NHRA timed 1/4 mile, per NEDRA)* 
*1.58 sec. 60 ft. time, 0-60 in ~ 2.9 seconds, 1/8 mile ET 7.2 @ 94.5 mph!*


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## jzamorah33 (Sep 13, 2009)

Regarding your choices: the first choice is your best. Normally you will find that the majority of people do not even use first gear to get the vehicle going due to the high torque output. Second gear is used for start. Also you will find that Azure Dynamics provides very good motors along with the controllers specifically for them.
Siemens also manufactures very good reliable traction motors which are liquid cooled and thus prolonging its service life.
Dual and quad motoring is yet in its infancy when it come to 0-60 in 4 or less.
I am actually seeking a vehicle that I can convert and experiment with, like a VW bug or T1 bus.
Best of luck and keep us posted with the progress.


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## jzamorah33 (Sep 13, 2009)

Regarding your choices: the first choice is your best. Normally you will find that the majority of people do not even use first gear to get the vehicle going due to the high torque output. Second gear is used for start. Also you will find that Azure Dynamics provides very good motors along with the controllers specifically for them.
Siemens also manufactures very good reliable traction motors which are liquid cooled and thus prolonging its service life.
Dual and quad motoring is yet in its infancy when it come to 0-60 in 4 or less.
I am actually seeking a vehicle that I can convert and experiment with, like a VW bug or T1 bus.
Best of luck and keep us posted with the progress.[/quote]


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## metricmind (Jun 19, 2009)

All Siemens motors are liquid cooled; thus far lighter than equal rated power air cooled ones (Azure). My company sold two Siemens systems (Simovert-6SV-1 inverters and 1PV5134 motors) to ProEv and I'm well familiar with this vehicle, we have some performance data.

About batteries - LiPo ones in fact will have more gravimetric (and probably volumetric too) power density than about any type of LiFePO4 batteries. Except for A123 (which are VERY powerful but have lousy energy density so are actually not too good as traction pack unless you're drag racing and don't care about range), you will always gain using higher terminal voltage battery. LiPo has 3.6V/cell nom, any LiFePO4 has 3.2V/cell, 8% difference.
So one the same weight of LiPo ones you'd go roughly 8% farther than on LiFePO4 (everything else being equal of course).

I would use 2 systems As ProEv using only if base car is 4x4 to start with
(which all Subarus are). It is not much more difficult than one motor and you loose weight of unnecessary transmission which you have to keep if you use single motor (even if you will use one fixed gear out of 6). Single gear is sufficient for "normal" driving in this case. See simulation for my conversion: http://www.metricmind.com/audi/main.htm With Single motor you might need to switch to lower gear if you tow or climb steep hill. If you gear too short to avoid this, you may not reach 100 mph top speed.

Do not use 4 motors one per wheel (hub motors or fixed with shafts). Synchronizing for stability and traction control is not trivial, let alone you need 4 inverters (expense). Efficiency of one larger motor is always higher than 4 smaller ones (or 2 medium ones for that matter), but we're talking about few percent difference for good motors. There are OEM systems that meant for drop-in installation in 4x4 arrangement (motor + single gear reduction and differential as one unit), but it's expensive for a hobby project. I can get my hands on BRUSA one (http://www.metricmind.com/products/brusa-asm-6-17-12/) but so far no takers.

If you want simplest conversion and decent performance, don't try to be too fancy, use one powerful enough system and you will be happy. This is quickest way to actually complete the project; trust me - I've done it both ways (more work is done on Audi than documented on the web site, but for various reasons it's not finished, one being complexity and totally foreign (to Audi) drive train components. Modifying axles and fabricating support brackets for entire new drive train(s) is not a hobby affair.

Hope this helps, good luck with your project,

Victor


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