Open Source Electric Supercharger

[Luckrider]

An Arduino might be overkill, but I'll be damned if I couldn't replicate the software functions provided by the ECU using one of those damn things.

[AN]

@neutron256 ... got some good info on the Seadoo supercharger ....
the drive ratio is 1:5 ... max engine rpm = 7750 i.e. max supercharger rpm is 39k rpm. Now at that rpm it is giving enough air to make 185hp (crank or wheel/propeller I am not sure).

http://members.iinet.net.au/~pauldaw...-SC_SF-low.pdf

Its 1.5L engine. Do you think at about 30k rpm you will be able to flow enough air to make any hp over stock ?

Anyhow ... once thing is very likey ... if the motor spins it to 35k rpm , we should have 5psi of boost

[neutron256]

Originally Posted by AN

@neutron256 ... got some good info on the Seadoo supercharger ....
the drive ratio is 1:5 ... max engine rpm = 7750 i.e. max supercharger rpm is 39k rpm. Now at that rpm it is giving enough air to make 185hp (crank or wheel/propeller I am not sure).

http://members.iinet.net.au/~pauldaw...-SC_SF-low.pdf

Its 1.5L engine. Do you think at about 30k rpm you will be able to flow enough air to make any hp over stock ?

Anyhow ... once thing is very likey ... if the motor spins it to 35k rpm , we should have 5psi of boost

Thanks that's great info. There are two versons of this supercharger the data you have is for the 17 tooth 185hp. The one I have is the 16 tooth from the bigger 1.8L 215hp engine, but I think the specs on the supercharger itself aren't that different.

I have no dubt that with the right brushless motor this will make some decent power, it's just a question of how much.

[AN]

Originally Posted by neutron256

Thanks that's great info. There are two versons of this supercharger the data you have is for the 17 tooth 185hp. The one I have is the 16 tooth from the bigger 1.8L 215hp engine, but I think the specs on the supercharger itself aren't that different.

I have no dubt that with the right brushless motor this will make some decent power, it's just a question of how much.

Yeah, I hope so too ... specially if that 185 number is at the prop and not the crank ... I would guess the charger eats up atleast 15 to 20hp.

Also, I see that the 215hp version comes with an intercooler ... I would love to find out that we need an intercooler .. and then not use it by de-tuning it a bit ..

I have my eyes on a couple of these blowers on ebay ... will pull the trigger as soon as you get some good results ... Thanks for testing it for the rest of us.

[neutron256]

Originally Posted by AN

Yeah, I hope so too ... specially if that 185 number is at the prop and not the crank ... I would guess the charger eats up atleast 15 to 20hp.

Also, I see that the 215hp version comes with an intercooler ... I would love to find out that we need an intercooler .. and then not use it by de-tuning it a bit ..

I have my eyes on a couple of these blowers on ebay ... will pull the trigger as soon as you get some good results ... Thanks for testing it for the rest of us.

Superchargers run at about 75% efficiency due to the mechanical losses it takes to actually power it. With the electric supercharger we're taking that loss over time while charging the dump pack, not continuously.

When it's on it's intended engine if it's making an additional 30hp output. It's actually making 40hp at a loss of 10 hp. The quick number which I'm sure is far from accurate would be that we could generate 4hp for every 1hp our motor can put in.

The KDE motor I'm looking at can do 3.72hp (3050 watts -9% efficiency loss) continuously. If we use the 1:4 calculation we'd be getting about 15hp. It raises to more like 26hp if you use the peak power rating of 5500 watts.

Of course the math isn't even close to that simple I'm sure, but it might give us some ballpark numbers.

Edit: An additional 15hp doesn't seem that impressive but when combined with my other mods it will probably get me the sort of power I'm looking for.

[Tenthousanddays]

Originally Posted by neutron256

Yep, my math comes out the same. If you figure a peak charge of 28V it's only 250 Amps. But that's still a ton of current.

A 36V (42V Peak) it drops to 166 amps which is a lot more reasonable.

Originally Posted by AN

Same here ... on both counts ... actually IT (BI) vs Infrastructure though

Anyhow ... the information I am looking for is ... that their language indicates that they have / will have multiple versions of each model ( direct drive / gear drive ) motor-compressor combos. I would want to know what combinations of Peak V, Peak I and Total Power will they offer. And what boost + CFMs will each of these generate.

Also, I am not sure I would want to run 9psi in an on/off fashion. It works for Phantom because the total boost is more like 4~4.5 psi. Once scenario where I would be OK with on/off boost will be where the wheel is big and heavy and builds boost gradually.

Anyhow, anxiously waiting for more details to come out and seeing actual specs. Critical piece then would be to set-up power delivery / recharge for this monster.

Originally Posted by Tenthousanddays

Yeah that seems like a hell of a lot, but that could be for peak power (redline) only if you wished? This is where PWM/Speed controller would come in handy (along with your whole Unichip setup).

Is that the right calculation anyway?

So I was thinking about this some more, because I'd really like to get more towards 7 or so PSI, which would be the defining factor in building a system myself rather than using the Phantom... In order to achieve 7kw of power on that motor, you need around 300amps. If you use a big enough battery... say two or three of these Odyssey PC925's, you should have plenty of amperage to power the motor at full blast for a couple minutes?

http://www.atbatt.com/odyssey-pc925t...ry.asp#related

Its 27Ah, with a 900A Hot crank surge... So even if you run the motor at full blast for 1/16th of an hour (3.75 min), you should be able to push out way over 300A (432A). Realistically speaking you probably wont be able to sustain 432A for 3.75 minutes - but pushing the motor at full blast for a minute or two doesn't seem out of the question...

Is this feasible?

[neutron256]

Originally Posted by Tenthousanddays

So I was thinking about this some more, because I'd really like to get more towards 7 or so PSI, which would be the defining factor in building a system myself rather than using the Phantom... In order to achieve 7kw of power on that motor, you need around 300amps. If you use a big enough battery... say two or three of these Odyssey PC925's, you should have plenty of amperage to power the motor at full blast for a couple minutes?

http://www.atbatt.com/odyssey-pc925t...ry.asp#related

Its 27Ah, with a 900A Hot crank surge... So even if you run the motor at full blast for 1/16th of an hour (3.75 min), you should be able to push out way over 300A (432A). Realistically speaking you probably wont be able to sustain 432A for 3.75 minutes - but pushing the motor at full blast for a minute or two doesn't seem out of the question...

Is this feasible?

My personal opinion is if you want to get that kind of power out of a system like this they you're going to need to go with a higher voltage system. Double the voltage, cut the current in half assuming the same total watts. The biggest problem with that will be charging I think. Charging 48V from a 12V alternator is no small task.

[AN]

Originally Posted by Tenthousanddays

So I was thinking about this some more, because I'd really like to get more towards 7 or so PSI, which would be the defining factor in building a system myself rather than using the Phantom... In order to achieve 7kw of power on that motor, you need around 300amps. If you use a big enough battery... say two or three of these Odyssey PC925's, you should have plenty of amperage to power the motor at full blast for a couple minutes?

http://www.atbatt.com/odyssey-pc925t...ry.asp#related

Its 27Ah, with a 900A Hot crank surge... So even if you run the motor at full blast for 1/16th of an hour (3.75 min), you should be able to push out way over 300A (432A). Realistically speaking you probably wont be able to sustain 432A for 3.75 minutes - but pushing the motor at full blast for a minute or two doesn't seem out of the question...

Is this feasible?

Math seems right but I still doubt the Odyssey can supply that kind of amperage. Specially if we are going to pay that kind of $$ for the batteries, might as well get Li-Iron-Phosphate. Those can give a lot higher current than AGM, long life , way more compact, can discharge 80% w/o damage, will hold higher voltage even when discharged over 50%, a lot less internal resistance ... seems like they are custom made for this setup ..

http://shoraipower.com/battery-specifications

The gains demonstrated by the Phantom setup are more than enough for me to pull the gun on ESC. But once I see the that there are so many apparent and glowing places where enhancements could have been made, I feel like a much better job can be done with a little effort. I would be happy to get similar psi numbers to Phantom .. may be a little more up-to ... 3~4 psi ... but it will be tough.

[AN]

Originally Posted by neutron256

My personal opinion is if you want to get that kind of power out of a system like this they you're going to need to go with a higher voltage system. Double the voltage, cut the current in half assuming the same total watts. The biggest problem with that will be charging I think. Charging 48V from a 12V alternator is no small task.

@neutron256, since you already have the 3 bank MinnKota charger, dont you think 36V setup should be easy. It just a matter of adding once more compact battery right ? The crank battery will be left wired as OEM ... no ?

[Tenthousanddays]

Originally Posted by AN

Math seems right but I still doubt the Odyssey can supply that kind of amperage. Specially if we are going to pay that kind of $$ for the batteries, might as well get Li-Iron-Phosphate. Those can give a lot higher current than AGM, long life , way more compact, can discharge 80% w/o damage, will hold higher voltage even when discharged over 50%, a lot less internal resistance ... seems like they are custom made for this setup ..

http://shoraipower.com/battery-specifications

The gains demonstrated by the Phantom setup are more than enough for me to pull the gun on ESC. But once I see the that there are so many apparent and glowing places where enhancements could have been made, I feel like a much better job can be done with a little effort. I would be happy to get similar psi numbers to Phantom .. may be a little more up-to ... 3~4 psi ... but it will be tough.

Whew... $330 for that 36Ah battery. 36Ah is pretty impressive though. And holy crap! It only weighs 5 pounds?! If it takes $660 bucks to successfully power a 7kW motor for 3 minutes - I think it's worth it. Especially with the size and weight. Its also only 6.5x6.1x3.4"... good find!

[AN]

Originally Posted by Tenthousanddays

Whew... $330 for that 36Ah battery. 36Ah is pretty impressive though. And holy crap! It only weighs 5 pounds?! If it takes $660 bucks to successfully power a 7kW motor for 3 minutes - I think it's worth it. Especially with the size and weight. Its also only 6.5x6.1x3.4"... good find!

We do not have to get 36Ah batteries ... we can go smaller with Li-Fe-Sulfate .. since they are deep cycle ... Also , we can have a 36V pack. Their 21Ah battery is around $170.
http://www.bigbadpowersports.com/sho...vbN6cR7yjw_wcB

Its very compact @ 5.51 X 5.83 X 3.23 inches and 2lbs. We can have 4 of them together in a 6 X 5.5 X 13 inch . This is only 5 inches high. MinnKota Charger can be stacked on top. Now that is a compact power storage and delivery system.

[neutron256]

Originally Posted by AN

@neutron256, since you already have the 3 bank MinnKota charger, dont you think 36V setup should be easy. It just a matter of adding once more compact battery right ? The crank battery will be left wired as OEM ... no ?

I am setup so I can test 36V but right now I'm favoring 24V just because I want to keep size/complexity to a minimum. I'll probably at least bench test 36V and see what kind of difference there is.

[Tenthousanddays]

Originally Posted by AN

We do not have to get 36Ah batteries ... we can go smaller with Li-Fe-Sulfate .. since they are deep cycle ... Also , we can have a 36V pack. Their 21Ah battery is around $170.
http://www.bigbadpowersports.com/sho...vbN6cR7yjw_wcB

Its very compact @ 5.51 X 5.83 X 3.23 inches and 2lbs. We can have 4 of them together in a 6 X 5.5 X 13 inch . This is only 5 inches high. MinnKota Charger can be stacked on top. Now that is a compact power storage and delivery system.

Thats a good plan. If we can send 36v to the eCycle motor, then 7kW of power would need less than 200A of current. Those batteries are only $175 each on Amazon. I like the idea of stacking the charger on top of the batteries too.

I wish I had 1500 lying around to get my hands on one of these eCycle ESC's so I could start testing it out...

[AN]

Okay .. found a more compact 3 bank charger ....

http://www.chargingchargers.com/char...l-pro/px3.html

Current is 12A/12A/12A .. Pretty much the same features as the MinnKota ... thie one is water proof , only 4 lbs and dimension are 4 X 6 x 5.5 inches.
The MinnKota looks a lot better but at 14.5 inches long will be hard to fit that under the hood.


Edit: nevermind the 3 bank is discontinued , 2 bank is is till available.