# multiple smaller AC systems combined for higher performance... possible?



## efan (Aug 27, 2009)

hey there,
not too many AC drives available for the diy community huh? gotta scramble...First I gotta say that I am not one of the most experienced members around here, but I am sure others will give their opinion and expertise....that said, I do not think any welding will be needed if you were to go with four ac50 system. you can have two motors side by side with a belt drive...but to reduce the complexity you can go with 2 MES-DEA systems instead..(http://shop.electro-vehicles.eu/shop/shop.asp) for about $17000 you can get two TIM 600 inverters and two of their *Mes-Dea 200-250W* (although there will be importing and shipping costs), check the above link and good luck!


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## Techie (Sep 19, 2009)

That is a start, my project is still in planning/saving the $$$ up...
I heard that EVNetics may be cooking something up with 3ph AC at some point, I wonder if there's any progress with that since SolJR is out now...


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## efan (Aug 27, 2009)

I have not heard of any updates, but even if they were to start offering an AC controller...what makes you think that it will be anymore affordable?


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## Techie (Sep 19, 2009)

I don't expect that they'd be more affordable, maybe on par with the others, but based on how the Solitons look, I'd expect the quality to be pretty good.

Digging in Curtis' site some more, they say that it's not possible to use 2 controllers with 2 motors linked in that way So I guess it's 2x 100kw systems that'll have to do. provided they can communicated to do the differential thing.


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## Nick Smith (Oct 26, 2007)

Techie said:


> Digging in Curtis' site some more, they say that it's not possible to use 2 controllers with 2 motors linked in that way So I guess it's 2x 100kw systems that'll have to do. provided they can communicated to do the differential thing.


Actually, Curtis specifically allows for this in the 1138 at least where they state "Built-in dual drive software allows easy setup of typical dual-drive vehicles, without VCL". It looks like you would need a steering angle sensor to do this and I really don't know how easy this would be overall. 

Most of the options for dual drive that I have come across either drive face-to-face to a common crown wheel on the differential, or drive in parallel through a "commoning" gearbox. This might be the best option if you will have "long" double motor setups. The BYD bus does have individual wheel motors and I suppose you could "common" 2 motors per side for each wheel.

Perhaps a better solution overall might be a Siemens 150kW motor from Metric mind and a Rinehart Motion Systems 150kW controller that should be in prototype build right now and available before the end of the year.


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## Techie (Sep 19, 2009)

I wonder what the $$$ of that is gonna be. I'd simply go with DC, however I have some hilly terrain to deal with and regen will be nice to have for that. It'd really be cool if I could convert the clutch peddle into a regen peddle, to use along side of the regular breaks. could save some wear.


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## Nick Smith (Oct 26, 2007)

Cost might be about the same as 4 ac50's but without the added problems of joining shafts etc, but yes, expensive! Would not quite be the same overall power either but as someone else mentioned, a pair of BRUSA motors or a pair of AZD ac90's would do the job too and run to about 200 kW. 

A couple of 9" motors with solitons could get you to 300! KW but would be pretty mean to your traction pack unless you go for a high voltage pack. The solitons can run from up to 340v pack (reportedly) so overall current draw could be kept down but still would be looking for the 1000A.

If you want regen though....


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## Bowser330 (Jun 15, 2008)

Techie said:


> is it possible to combine say 2 ac50 motors with shafts welded together?
> my idea is to put 4 ac50 motors (each with its own Curtis 1238-7501 controller) 2 for each rear wheel in a direct drive system using only gear boxes separate for each wheel (no diff) on my car. That would make 200Kw available for $18000ish... or are there 2 100 kw systems around for less? (of course they'd have to communicate to work as differential, Curtis claims on their site that they can do this with their controllers).


Check this system out techie...

http://currentevtech.com/Drive-Syst...lers/80KW-BLDC-Motor-and-Controller-p167.html

80kw peak for 6K$ (i was told it might be able to reach 100kw burst, email them for confirmation)

Only 12K$ for two systems and peak 160-200kw...

instead of doing gear reductions for each rear wheel, you could probably more easily do an AWD setup and get an independent suspension for each axel with a defined gear ratio based on the peak speed you want to be able to reach, if you keep that peak speed low, you will gain on power in the low-end and your acceleration would be really good, e.g. Tesla Roadster.

However Nick Smith makes a really good point, if you are looking for power...then AC will cost A LOT more than a DC system..
Warp11HV + Netgain Control Warpdrive 360V 1400A = 3500+4400 = 7900$ for 378kw peak (500hp) & flat torque cruve of 400+ftlbs from 0-rpm


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## Techie (Sep 19, 2009)

I'll check it out. The problem with AWD in my build is that the car is RWD only... I'll need to find a way to get to the front wheels with drive. I have been looking for a way. It's a '62 Comet (Mercury) btw.


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## majorpayne (Mar 27, 2011)

Check out the White Zombie over at Plasma Boy Racing: http://www.plasmaboyracing.com/whitezombie.php

They run a custom siamese 9" Netgain motor with a Zilla 2K. so basically two motors in one, I'm not sure how they pulled it off or any specs but I do know that its got a top speed of 129 mph! Shoot them an email and i'm sure that be glad to give more info.

You'd have to ditch your AC plan but this could be significantly easier and cheaper than 4 AC50's.


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## Bowser330 (Jun 15, 2008)

Techie said:


> I'll check it out. The problem with AWD in my build is that the car is RWD only... I'll need to find a way to get to the front wheels with drive. I have been looking for a way. It's a '62 Comet (Mercury) btw.


well you can swap in a front drive axle from a 4x4/awd vehicle from the junk yard into your car...It actually could work out quite well with only 2 AC motors.

The one in front could be direct-drive geared to your max speed, the other can be mounted to the transmission that is routed to you RWD existing axel and you can shift it to keep the gearing optimal...best of both...


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