# New series hybrid help?



## terra (Mar 8, 2010)

Any info on voltage, amount of batteries, power consumption, etc. will also be appreciated. I think I've settled on AC motors, also talking to AC propulsion. I'm not sure on how much power I need to reach my performance goals. I understand the whole peak vs. continuous situation, but no firm idea on how much power it will take. Any takers?


----------



## major (Apr 4, 2008)

terra said:


> but no firm idea on how much power it will take. Any takers?


Hey terra,

My first thought...Are you for real?



> The vehicle it's going in weighs 5300lbs and has to meet very specific goals. Being able to cruise at high speed (up to 200 mph) and accelerate from 0-60 in under 5 seconds are paramount.


Second thought...Maybe you are rich!

Anyway, off hand I'd say more than 1000 hp.

What would it cost you to meet your paramount specific goals with an IC engine? An electric system is bound to be more costly, maybe by a factor of 10.

But hey, good luck with your project. Keep us informed as to your progress.

major


----------



## terra (Mar 8, 2010)

major said:


> Hey terra,
> 
> My first thought...Are you for real?
> 
> ...


Most definitely am for real. Have roughly $150,000 to get this done. 
Why would I need 1000hp? ICE can be done with less than half that.
Thanks for the...help?


----------



## major (Apr 4, 2008)

terra said:


> Why would I need 1000hp? ICE can be done with less than half that.


It was just "off hand", but I don't think unrealistic. NASCAR is up into the 750 to 800 hp. And with a lot less than 5300#. I don't think you can beat those guys with an electric for your budget. But give it a go


----------



## terra (Mar 8, 2010)

major said:


> It was just "off hand", but I don't think unrealistic. NASCAR is up into the 750 to 800 hp. And with a lot less than 5300#. I don't think you can beat those guys with an electric for your budget. But give it a go


It's not a track car, no need to compete with nascar. My performance goals can be accomplished with 500hp ICE, but I have no idea as to the electrical equivalent. I won't be throwing this 5300lb beast around Laguna Seca, just freeway and city driving.


----------



## major (Apr 4, 2008)

terra said:


> It's not a track car, no need to compete with nascar. My performance goals can be accomplished with 500hp ICE, but I have no idea as to the electrical equivalent. I won't be throwing this 5300lb beast around Laguna Seca, just freeway and city driving.


200 mph ain't easy, whether you're on the freeway or the track or the salt flats. If you can do it with 500 hp from an ICE, then you'll need 500 hp from an electric motor. Power is power, and 200 mph will take power. I think you'll fall short on power with 500, so prove me wrong  A modified EV1 did 183 mph years ago with maybe about half that power. I think it took 4 or 5 miles to get there, so not what you could call cruising.


----------



## terra (Mar 8, 2010)

major said:


> 200 mph ain't easy, weather you're on the freeway or the track or the salt flats. If you can do it with 500 hp from an ICE, then you'll need 500 hp from an electric motor. Power is power, and 200 mph will take power. I think you'll fall short on power with 500, so prove me wrong  A modified EV1 did 183 mph years ago with maybe about half that power. I think it took 4 or 5 miles to get there, so not what you could call cruising.


I don't want to prove you wrong, I'm not on a personal vendetta haha. Obviously I want to accomplish this without spending millions, so I'm asking for some direction. A Bentley Continental weighs..5500? And has 550hp. Can do 200mph or damn close, and meet my acceleration goals. You're saying I'll need 500hp regardless of the motor, yet the ICE is supposedly measured at peak and electric is continuous? So where does that leave me? I left emails with UQM and AC Propulsion, so I'll see what they have to offer but I'd like to gain a bit of personal knowledge too.


----------



## DavidDymaxion (Dec 1, 2008)

You could talk to these guys: http://www.ssi-racing.com/ , they'll sell you a powerful drive system.

Something to keep in mind is most of the high power electric guys are doing the 1/4 mile. Running at their power levels will melt things going for a multiple mile land speed run.

Also, an aerodynamic vehicle gives you speed for free. Pontiac Firebirds are the fastest stock bodied vehicles that have run on the Salt Flats, one has gone over 300 mph. You might be able to do something better with custom bodywork. Something I think would be too awesome: Make a replica of the GM EV1, the most aerodynamic production car ever.


----------



## terra (Mar 8, 2010)

DavidDymaxion said:


> You could talk to these guys: http://www.ssi-racing.com/ , they'll sell you a powerful drive system.
> 
> Something to keep in mind is most of the high power electric guys are doing the 1/4 mile. Running at their power levels will melt things going for a multiple mile land speed run.
> 
> Also, an aerodynamic vehicle gives you speed for free. Pontiac Firebirds are the fastest stock bodied vehicles that have run on the Salt Flats, one has gone over 300 mph. You might be able to do something better with custom bodywork. Something I think would be too awesome: Make a replica of the GM EV1, the most aerodynamic production car ever.


Thanks for the link, and I'll keep that in mind. I understand there are several design and technological issues here but I'm trying to work through it. I already have the custom bodywork so that won't be changing. Thanks for the ideas though.


----------



## major (Apr 4, 2008)

terra said:


> You're saying I'll need 500hp regardless of the motor, yet the ICE is supposedly measured at peak and electric is continuous? So where does that leave me?


If you want to cruise at 200 mph then you need to have that power available on a continuous rated basis regardless of the power plant. Obviously you can't carry enough energy to do that continuously, but considering the time it takes you to accelerate to that speed and then cruise, 5 or 10 minutes will seem like continuous to the motor and drive thermal management system. I'd venture to say if you use the required 200 mph power as peak rating for an electric motor; it will fail before you reach 200.


----------



## terra (Mar 8, 2010)

major said:


> If you want to cruise at 200 mph then you need to have that power available on a continuous rated basis regardless of the power plant. Obviously you can't carry enough energy to do that continuously, but considering the time it takes you to accelerate to that speed and then cruise, 5 or 10 minutes will seem like continuous to the motor and drive thermal management system. I'd venture to say if you use the required 200 mph power as peak rating for an electric motor; it will fail before you reach 200.


Thanks. The motors I was considering are..134 hp continuous, 200 peak. 300lbft continuous, 480 peak. 5000rpm. I'm wondering what kind of performance they would offer, and what kind of battery supply I'd need. I can tone down the top speed, but not hugely. Maybe 170mph. I'm open to other motors and methods though.


----------



## Tesseract (Sep 27, 2008)

terra said:


> ...The motors I was considering are..134 hp continuous, 200 peak. 300lbft continuous, 480 peak. 5000rpm. I'm wondering what kind of performance they would offer, and what kind of battery supply I'd need. ...


First off, you should at least determine how much power you will actually need. A good website for estimating that - which I know compares well with real-world data - is:

http://www.apexgarage.com/tech/horsepower_calc.shtml

Secondly, if the manufacturer says their motor can deliver 134hp continuous then that IS the performance to expect in this application. Anything over 5 minutes might as well be continuous from a thermal standpoint. Peak power is typically tolerable for 5 to 30 seconds, btw, and typically requires running at greatly reduced power for several minutes afterwards to cool down.

Thirdly, it may take 400-500hp to travel at 200mph, but you will also need to devote a considerable amount of power to applying downforce. IIRC, Formula 1 cars actually spend more power on downforce than they do on propulsion. Something to consider.

Fourthly, if it takes your vehicle, say, 400hp (300kW) to go 200mph and you have a 30kWh battery pack then you can drive for all of 6 minutes. That's assuming the pack can deliver the needed current, etc... If you want to be able to drive indefinitely at that speed you need a 300kW generator (assuming it and the charger are 100% efficient - which they aren't, of course).

In contrast, gasoline contains approximately 33kWh per gallon - if you want to go fast for a long period of time, it's hard to beat that kind of energy density.


----------



## terra (Mar 8, 2010)

Tesseract said:


> First off, you should at least determine how much power you will actually need. A good website for estimating that - which I know compares well with real-world data - is:
> 
> http://www.apexgarage.com/tech/horsepower_calc.shtml
> 
> ...



Great read, I appreciate it. I looked at that calc, some #'s I got were..
155 mph = 270 hp
170 mph = 353 hp
180 mph = 416 hp
200 mph = 567 hp
I noticed dropping the weight didn't affect needed hp much. What would be your suggestion?


----------



## Tesseract (Sep 27, 2008)

terra said:


> ...
> I noticed dropping the weight didn't affect needed hp much. What would be your suggestion?


No, weight mainly affects rolling resistance and acceleration; above 50mph most of the power is used to punch a hole in the air.

So, given that, reducing the frontal area and the drag coefficient are the two most important things you can do to reduce the power required to go a certain speed.

Ironically, a heavy vehicle might require less power at 200mph than an otherwise identical but lighter vehicle because it won't need as much power diverted into producing downforce.

I design high power electronics for a living, though, not race cars, so I'm not really all that qualified to comment on what it takes to go fast. In general, I solve such problems with brute force


----------



## terra (Mar 8, 2010)

Tesseract said:


> No, weight mainly affects rolling resistance and acceleration; above 50mph most of the power is used to punch a hole in the air.
> 
> So, given that, reducing the frontal area and the drag coefficient are the two most important things you can do to reduce the power required to go a certain speed.
> 
> ...



Interesting, I'll see what I can do drag wise. Brute force...why does that appeal to me so much? haha.


----------



## terra (Mar 8, 2010)

Could the battery power be used under a certain speed, kicking on the engine/generator when battery got low, but having the engine/generator constantly on when above that set speed to provide a more constant flow to the electric motor?


----------



## major (Apr 4, 2008)

Hi terra,

I asked 


major said:


> What would it cost you to meet your paramount specific goals with an IC engine?


You say


terra said:


> A Bentley Continental weighs..5500? And has 550hp. Can do 200mph or damn close, and meet my acceleration goals.


I looked up the price. Give or take on the model choice and options, it runs about $200,000.

I said 


major said:


> An electric system is bound to be more costly, maybe by a factor of 10.


Meaning I think your budget is low. Are there any EVs out there which come close to your goals? But hey, I don't want to discourage you. I'd love to see you do it.

Regards,

major


----------



## major (Apr 4, 2008)

terra said:


> Could the battery power be used under a certain speed, kicking on the engine/generator when battery got low, but having the engine/generator constantly on when above that set speed to provide a more constant flow to the electric motor?


Sure. But that doesn't change the motor requirements in a series hybrid.


----------



## terra (Mar 8, 2010)

major said:


> Hi terra,
> 
> I asked
> 
> ...





major said:


> Sure. But that doesn't change the motor requirements in a series hybrid.



Yes that Bentley costs $200k retail, I'm talking build cost though. I know there aren't any EV's similar to this, but hey..advancements need to happen right?

I know what you mean about the motor requirements, I need a strong one for sure. Will a good diesel motor and generator provide the current needed to run an electric motor, with the batteries helping out on hard acceleration?

Budget...can be worked with. I've got several advantages in the field which should drop the price a bit.


----------



## major (Apr 4, 2008)

terra said:


> I know what you mean about the motor requirements, I need a strong one for sure. Will a good diesel motor and generator provide the current needed to run an electric motor, with the batteries helping out on hard acceleration?


Hi terra,

I was talking about the electric motor. I call the electric motor a motor and the ICE an engine. Sorry about the confusion. 

In the series hybrid, all the wheel power comes from the electric motor. So, regardless where the electric power comes from (batteries or generator or combination) it does not change the power requirements of the electric traction motor.

Sure, you can get the current from a generator. It has to be appropriately sized. And can be powered from any number of engine types. But I'm an electrical guy. In fact I hate engines. Love motors/hate engines. But I have done hybrids before. Both series and parallel. Just not on a vehicle as small as yours 

Great. You want to push the envelope. Hope you got some useful information from us.

Regards,

major


----------



## terra (Mar 8, 2010)

major said:


> Hi terra,
> 
> I was talking about the electric motor. I call the electric motor a motor and the ICE an engine. Sorry about the confusion.
> 
> ...


I think I may have misphrased it. I got what you meant, I just didn't ask my question properly haha. Are there generators capable of powering an electric motor suitable for my application? I'm not familiar with generator sizes and such, so it might be as big as a room for all I know. Would a small diesel engine powering a generator possibly provide the electricity needed to power an electric motor? Or is my scale way off here...

By the way, I appreciate the help.


----------



## major (Apr 4, 2008)

terra said:


> Are there generators capable of powering an electric motor suitable for my application? I'm not familiar with generator sizes and such, so it might be as big as a room for all I know. Would a small diesel engine powering a generator possibly provide the electricity needed to power an electric motor? Or is my scale way off here...


If the motor requires 300 kW to power the vehicle and you get that power from the generator then the engine powering the generator needs to be about 350 kW. Roughly speaking, the generator is about the same size as the motor. How big the engine is? Ask an engine guy 

Now if you want to develop something new, use a turbine and high speed alternator to generate the electrical power. That will reduce the mass of the electrical power plant, but increase the budget.

For sustained high speed travel (200 mph cruising), series hybrid is likely a poor choice due to the extra energy conversions (mechanical to electrical to mechanical) unless you have a trump card, like a small efficient turbo alternator. My opinion anyway.

major


----------



## terra (Mar 8, 2010)

major said:


> If the motor requires 300 kW to power the vehicle and you get that power from the generator then the engine powering the generator needs to be about 350 kW. Roughly speaking, the generator is about the same size as the motor. How big the engine is? Ask an engine guy
> 
> Now if you want to develop something new, use a turbine and high speed alternator to generate the electrical power. That will reduce the mass of the electrical power plant, but increase the budget.
> 
> ...


Ok so the generator is usable haha. Turbine and high speed alternator..I've got a friend in turbines, I'll make some calls and explore that idea. Again, thanks for your help, I owe you a beer. I'm going to spend a couple days calling companies and planning something out. I'll be back once I get hard info. If anyone else has suggestions, feel free to post up.
Thanks,
Alex


----------



## One Equals Two (Feb 25, 2010)

Just to throw in a little tidbit of info, I researched large generators for high power 300Kw+ applications, and I am here to tell you that a car engine is the way to go for a generator. Also, energy conversion will net you a loss of nearly 40% (generator to battery to motor). Also, For example, the Volvo 13L generator uses something like 10.4 gallons an hour at 400 Kw if I remember correctly. It also weighs 6 tons. 

And, why would you want to "cruise" at 200? Where are you going to be? I've been near 170 mph and I nearly peed my pants!

Also, it's nearly impossible to cruise at that speed. The car I was in (a Mazda RX8 modded), used 9 gallons of gas in 8 minutes at that 165 mph, or in otherwords....2.44 mpg.


----------



## terra (Mar 8, 2010)

One Equals Two said:


> Just to throw in a little tidbit of info, I researched large generators for high power 300Kw+ applications, and I am here to tell you that a car engine is the way to go for a generator. Also, energy conversion will net you a loss of nearly 40% (generator to battery to motor). Also, For example, the Volvo 13L generator uses something like 10.4 gallons an hour at 400 Kw if I remember correctly. It also weighs 6 tons.
> 
> And, why would you want to "cruise" at 200? Where are you going to be? I've been near 170 mph and I nearly peed my pants!
> 
> Also, it's nearly impossible to cruise at that speed. The car I was in (a Mazda RX8 modded), used 9 gallons of gas in 8 minutes at that 165 mph, or in otherwords....2.44 mpg.



Ya I'm working on a smaller generator concept with a local company. Why would I want to cruise at 200? Why not? I've done 180 without much fuss. I'm not willing to give up the performance of an ICE, so electric will have to step up here and find a solution.

Also, I said cruise at high speed. Up to 200 mph. I don't intend on doing 200 for hours..but high speed definitely.


----------



## DavidDymaxion (Dec 1, 2008)

What about flipping things the other way? Going Insight instead of Prius? Instead of having a fossil fuel motor help the electric motor, have the electric motor help the fossil fuel motor.

For example, start with an ICE that barely hits 200 mph, and then add some lithium batteries and an electric motor to help accelerate faster to that point. You could still run pure electric at low speed.

The closest thing to cruising 200 mph in the U.S.A. is open road racing:

http://www.openroadracing.com/


----------



## terra (Mar 8, 2010)

DavidDymaxion said:


> What about flipping things the other way? Going Insight instead of Prius? Instead of having a fossil fuel motor help the electric motor, have the electric motor help the fossil fuel motor.
> 
> For example, start with an ICE that barely hits 200 mph, and then add some lithium batteries and an electric motor to help accelerate faster to that point. You could still run pure electric at low speed.
> 
> ...



I would never have considered that...I'll definitely look into it. Thanks for the suggestion. And who ever said it's for the USA...


----------



## DIYguy (Sep 18, 2008)

I can't believe you gents are all taking this fellow seriously.... lmao.....


----------



## terra (Mar 8, 2010)

DIYguy said:


> I can't believe you gents are all taking this fellow seriously.... lmao.....


And why's that? Because I don't know everything there is to know about electric vehicles? Or because I don't want to putter around at 20mph? Or simply because I have the funding to get this done but need some input on products?

Don't post useful information.
Thanks.


----------



## DavidDymaxion (Dec 1, 2008)

That's why I mentioned it... 1 day a year of Open Road Racing is a poor substitute for daily autobahn! Where are you planning to go so fast?


terra said:


> I would never have considered that...I'll definitely look into it. Thanks for the suggestion. And who ever said it's for the USA...


----------



## terra (Mar 8, 2010)

DavidDymaxion said:


> That's why I mentioned it... 1 day a year of Open Road Racing is a poor substitute for daily autobahn! Where are you planning to go so fast?


I'm moving my company and most of my customer base to Germany in 3 months. I mostly work in ICE, but I have a client looking to produce a one off car meeting these specs. Unfortunately I have next to 0 experience in EV, so here I am!


----------



## DavidDymaxion (Dec 1, 2008)

Here is a company that makes hybrid kits. The motor splices into the driveshaft, and the controller plugs into the car's harness. It just uses the car's existing signals for pedal position, rpm, etc. to control the motor. I have ridden in one, it seemed to work well and the builder said he had much better gas mileage.

http://www.go-ev.com/EMIS.html


----------

