Electric Supercharger
 

Why didn't anyone think of this before now?

Electric Supercharger Boosts Torque 50% and Reduces CO2 by 20% : TreeHugger

As is always the case with my posts, I'm curious what those wiser than me think.

I know it's not Fossil Fuel Free, but I only frequent this part of the forum. Please feel free to re-post this more appropriately if need be.

I love Torque!

Why use electric power to blow more air into the engine when you could use the motor to directly power the car? You're just introducing more efficiency losses into the system. Plus, if you couple it to the drive train you can use it for regenerative braking.

350 Amps draw while accelerating?!!? Wow, that is just about the same amounts of amps that the starter draws on a cooler day.

Good implementation of product and they have some good ideas for other things on thier website.

I bet it's going to be pricey though :(

I guess the most obvious question for me is if this can be cheaply retrofitted to existing cars?

Burning less Fossil Fuel is a step on the path to Fossil Fuel free.
All the better if it's a cheap step.

How does an electric supercharger that forces more air into the engine burn less fuel? :)

TomO -

I looked at the 220 Amps steady-state. I think my alternator is rated at 90 Amps on my 1.9L engine. I think they are hoping to target larger displacement engines :

A solution for truckers?

CarloSW2

I'm gonna play along for a second and assume it does work.

The "CO and fe gains" come from downsizing the engine i.e. put in a 1.0 where a 1.6 used to be, so no, slapping one on your wheels won't help unless you downsize the engine too.

At this point I fail to see how this offers an advantage over a turbo. Yeah, they had their pretty graph, but properly sized turbos work over different rpm ranges.

In the context of vehicle design, given the same power output, it allows a manufacturer to downsize the engine and improve average efficiency.

You just mentioned how it provides an advantage. Unless the turbo is designed to operate a low loads/speeds, and in that context limits power output, adding this, just like adding a conventional supercharger, can greatly improve low speed torque.

I understand that, but he was talking about bolt on things that help FE. At least thats the way I read it.

Erm... so put the right size turbo(s) on it, that pretty much works right? Or supercharge it. Or pick what you want- low end grunt or high end scream. Me, I don't need em both.

low speed torque.

start this whole fiasco with a 3 main boxer all natural aspirated and see how much electric supercharger babble gets buried. they can't even vtec an inline four into mimicking a two valve 50 year old version. How far backwards does engineering go ? anybody?

diesels and long slow burn use a turbo better than any machine on earth using faster fuels than diesel. max rpm 2100.

an engine that torques anyway, finds turbo power <3k. An old subaru engine maxxed at 2800.

This nonsense. I gotta headache. :confused:

Electric Supercharger, anyone?

http://i4.ebayimg.com/02/i/001/4e/4a/5e3a_12.JPG

Didn't this idea get shown the bricks years ago?

I seem to remember that it just takes too much electrical power to create enough airflow at high engine speeds to actually create a supercharger's effect of increasing intake volume by any reasonable amount.

In fact, many of the "electric superchargers" that were tested restricted airflow, keeping the manifold under vacuum even under full "boost" conditions.

350 amps under acceleration? the motor on my electric car has a 350 amp slow blow fuse, sure it peeks higher for a few seconds if I totally floor it... but under normal loads 200 amps or less and this is driving the wheels.

http://www.youtube.com/watch?v=XkQTHhCjyc8

:thumbup:

I actually watched a ricer in a Honda Civic lose to a Neon, then duct tape a 2-stroke leaf blower to his intake through a hole in the firewall, and win against the same Neon.

All I had to say was "Wow."

What people don't account for when considering boost is the fact that ANYTHING over the normal vacuum for your RPM and throttle angle is boost - even though it's not actually pressurizing the intake, it's still boosting the VE of the engine by reducing pumping losses.

The problem with the Electric Supercharger that I posted above is that it simply can't flow enough air to keep an engine happy. Often, you'll find similar things that are actually trolling fans for boats. They can't move 300 CFM of air on good days, and people honestly think they're making a difference in top-end HP. Well, they are, actually... they're REDUCING it.

Christ -

That's what I was thinking. I am giving it the benefit of the doubt for now and just specumalatin'. Maybe I'm giving Treehugger too much credit.

Who is "Controller Power Technologies"? :

Controlled Power Technologies... Background
Ok, it looks like they're carving a niche out of the EU emissions legislation.

Now, who is Visteon? :

Visteon - Wikipedia, the free encyclopedia
Sooooo, at least Visteon is the real deal. But maybe they sold their "rotten fruit" to CPT.

"Switched Reluctance Drives Limited" is for real too :

Switched Reluctance Drives

CarloSW2

I saw theses guys at SEMA one year.
It does in fact move a poop load of air (my estimate was 3x a commercial leaf blower); but thats all I can vouch for.

350 Amps huh? So about 5kw under acceleration. 1.45 atmospheres on a 1.2l is nice.
350 amp burst for what? a half minute? It could work if the electronics were all taken care of and you used a big enough battery pack.

The problem with the "electric superchargers" was that they were simply a leaf blower mounted to the intake. If they were driven more like a true turbo/supercharger system tied to the throttle and RPM and the electrical system was upgraded for the large power demand it could work. The main problem is that 5kw is being used to feed more air into the engine. It's on a 12volt system for which that amperage is too high for more than a few brief bursts like the starter. The solution is to use a higher voltage motor or bigger batteries. A 48volt motor with 4- 12volt batteries with 25amp/hour capacity would provide about 10 minutes of boost per charge. You really only need a few minutes at a time but the pulse amperage is really dependent on the battery.

If it means using a 5kw motor to boost the engine's displacement, you know people are going to take the boost over using a 5kw motor to the wheels.

Foolishly, of course, because no one will actually do the math. They'll hear the word "boost" and jump on it. Of course, one could downplay the idea by calling the IMA system "boost" as well, since that's one of it's potential uses - to give a "boost" in acceleration for short "bursts". Kind of like E-Nitrous.

Here is a thought for y'all.

Use the electric supercharger as a means to downsize your engine. The supercharger only needs to provide bursts of power when you really need it. Cut the engine displacement in half.

Now here is the kicker. Normal engines use a throttle plate to restrict the air available to the engine. Vacuum can do a certain amount of useful work. With an electric supercharger you have the potential to use it as a generator when it is not providing boost to the engine.

Throttle restrictions to control engine speed create no energy, while the electric supercharger could provide a means of capturing energy from the same effect as a throttle plate. Control of the throttle would be by the amount of load you applied to the generation phase of the electric supercharger.

Not sure if it would be enough to provide all the electrical needs of the vehicle, but if it was combined with a small Rankine cycle power supply using exhaust heat it should be able to drive every accessory on the vehicle.

I am not an engineer so the technical calculations are beyond my capabilities, but you can't argue the fact that using available vacuum to create electrical energy, compared to normal throttle plate losses, is in fact free energy.

This would beat any other presently available supercharger or turbocharger option. Also consider that electrical power generation would be continuous, any time the engine was running, even when there was little or no manifold vacuum. That's free energy for supercharger application, at least to a certain point.

The supercharger would have to be a positive displacement design, unlike the one shown in this thread.

Regards
Mech

Now here's something to wrap your brain around:
The VX motor in stock form flows 134.45 CFM at 6000RPM.
Even though the Bilge Aerator fans (4") will flow 250CFM (on a good day) and some of the model aircraft "Jet Turbine" Engines will flow 300CFM, that is still an improvement over the CFM of the VX motor.

BTW: the VX motor flows about 50CFM cruising on the highway at 2200RPM.

Since the VX uses a MAP system and doesn't actually know the amount of air coming into the system (it calculates it based on known VE and by what the O2 sees), it might be possible to use a fan like this to eek a little more power for accelerating or leaning out even more during highway cruising (althought the ECU will compensate for the air during cruising eventually).

Mech - I don't think the Fan could produce a fast enough response, honestly, to replace the throttle blade. A fan's blades would be the most restrictive when spinning fast, I think... slowing them down would make them least restrictive, until they're finally stopped, which would be the quintessential "full throttle" of the system. The issue with that scenario would be getting the fan blades moving again... I think you'd want the system to default to throttle closed, wouldn't you?

TomO - You could run the MAP on a reference line that takes a reading from a pre-charged section of the intake system, but you'd have to put the charger behind the throttle body. It wouldn't be altogether difficult to do, though, since you can remove the TB and add a flanged pipe w/ the aerator in between the flanges, then relocate the MAP to just before the aerator, where it would still create a "false" vacuum.

While you may be correct for the figures from a VX engine, and even other engines, the fact still remains that the additional airflow causes more electrical load (10A at 12VDC is 120 Watts) and the whole setup was originally designed (and is still being touted) for more power, not the ability to cruise lean.

This is tempting... I might just have to pick up a bilge fan on the cheap from Fleet Farm and play with it.
I forgot to mention that the system would have to have it's own deep cycle sitting in the trunk so as to not load down the alternator, sorry. I might have a spare YellowTop Optima to play around with and try messing around with some form of this system. Time for the thinking cap!

Anybody have a price on this thing?

I doubt it would give you any more FE improvements than, say, bolting a big honking alternator on your car and doing a mild do-it-yourself hybrid. It's a little more complicated than it sounds, but doable.

Finest regards,

troy

It would require a positive displacement supercharger that used no reciprocating parts and had super lightweight components.

A fan won't do the job. It might work with a rotary vane pump. Variable displacement would work even better. On the same shaft add the steam engine driven by exhaust gas residual heat.

Both of those energy sources are from the same energy that is normally wasted in a conventional setup. BMW was working on a steam powered accessory drive system that used exhaust heat. They claimed a 15% mileage improvement.

67% (EPA figures) heat energy losses in a typical passenger car would provide a lot of power for the initial acceleration to reduce the dramatic amount of fuel lost in those circumstances.

Additional electrical loads could be compensated for by increasing the alternator charging load on any DFCO event, which would save friction brakes.

I doubt any forced induction will make much of a difference in mileage, unless you had a smaller displacement engine. Ford is going that route with their eco-boost engines, if I understand their developments correctly.

Take the average pickup truck, SUV sized vehicle and use a 2.5 liter diesel engine. Maybe even 2 liter. Get it to produce 200 HP and good torque when you really need it, but also give you great higher load BSFC cruise capability at highway speeds.

I think that is the way they will get those full sized vehicles up to the 30-35 MPG range.

Just thinking out loud.

regards
Mech

I gotcha. That may have to do with the test mule they're using. The 2.0T is mostly about high end power, so there are trade-offs in terms of the compressor's efficiency map. Having something that can help spool up the turbo quicker may help the engine operate (marginally) more efficiently, or maybe they're just BS'ing, since I didn't see anything about the test methodology.

That's just the problem, at least from the POV of design, there is no right size turbo, or turbo(s), or even twin-charged setup. Each setup has trade-offs, be it greater max power output and poor low end power output/efficiency, decent efficiency over most of the operating range, but lower power levels, or decent power/efficiency but greater weight/complexity. All this does is possibly provide another tool for forced induction in between what's currently offered AFAIK.

Using a blower to throttle an engine is an interesting concept...

Just like a TC/SC, but electric! ;)

Nobody has throttled an engine with a tc/sc have they?

I wonder if there is enough energy in the intake airstream to be worth harvesting.

It's only .00005 watts, Frank.
 

Apparently, one of my posts didn't post...

The way to throttle an engine with a fan would be to run it at a high speed for low throttle, and run it at zero speed for max throttle... the problem with this, is that it wouldn't be anything close to instant throttle response, and the amount of energy scavenged would directly affect the VE of the engine - according to the laws of conservation of energy, when you extract energy from a mass, the mass would then have that much less energy to give.

Since you're extracting energy from air flow, any energy extracted would cause that flow to slow down, negatively impacting the engine's intake charge.


Per this site:

We can substitute the intake fan for a wind turbine here, and substitute the influx of air for wind.

We can determine the power that can be extracted from the intake air by using the following formula:
P = 0.5 x rho x A x Cp x V3 x Ng x Nb

We'll replace the variables with nominal figures, assuming we're at sea level, and the fan has a 4" diameter, using the Betz limit, which is considered universally unreachable, as our coefficient of performance Cp, assuming our generator is 80% efficient (Ng), and assuming there is no gear or drive losses (Nb):

P = 0.5 x 1.225 kg/m3 x .008 m2 x .59 x V3 x .8 x 1

The only plug left to make is the actual volume of air in M/S.

50 CFM works out to 0.0235973722 m/s3, which replaces V3 in the equation:

P = 0.5 x 1.225 kg/m3 x .008 m2 x .59 x 0.024 m/s3 x .8 x 1

So, given the best know circumstances, the power generation capability would be: 0.0000555072watts at idle speed using 50 CFM of airflow.

Yep - Five one-hundred-thousandths of one watt, under nearly perfect circumstances.

And that's extracting an enormous amount of the energy from the airflow, so much so that the engine couldn't idle any more, with perhaps the most efficient equipment currently known to exist.

Anyone care to check my math? I think I messed up somewhere.

I'd say you messed up. It would be based on the engine's displacement for one thing so there is no one answer.

I was using the figure given by TomO for intake flow of the VX engine (1.5 liters) at idle, 50CFM.

I think there's something wrong with my conversion math, though. I had to convert CFM to M/S^3, and convert 12.56 IN^2 to M^2.

I still think by just using a properly sized turbo you will get the same gains or better.(living proof is my engine)

Turbo technology has vastly improved in the last five years.

Just a correction: the 50CFM seen in the VX motor is at 2200rpm, not idle. At idle (550 RPM) it's 12.32CFM.

Later, I'll restate the equation with a larger engine.
 

Woops, thanks!

Anyone care to check my math?

I did a similar calculation for someone claiming that they made a difference with a squirrel cage fan in a fog light hole in another thread, it came to less than 100 Watts produced at highway speed...

Tonight, I'll redo the formula with 100% VE at 6k RPM. We'll see the max theoretical figure that the 1.5 L engine could produce.

Or, I could do the same calculation for a 12 liter engine at 100% VE, if that would suit anyone's thoughts better.

Either way, the number is ridiculously low, and the engine still wouldn't be able to run properly with that much energy being extracted from the intake stream.

Remember, the Betz limit is there for a reason... the theoretical max extraction of energy from wind is 59%, because at 60%, equilibrium is reached (according to Betz, anyway.) If this weren't true, a brick wall would be 100% efficient at harnessing the wind's energy, since it would not allow any of the wind to pass.

With a fan, it's rotational speed is inversely proportional to the amount of air allowed to pass. The fan would provide more resistance to air passage at higher speeds, and less resistance at lower speeds, to the extent that (unlike I said earlier) full throttle would not be a stopped fan blade, but instead, a blade that spun only enough to allow an unrestricted passage for fluid (air).

Without actually doing the calculations, I can theorize that the fan in the intake would reach equilibrium, in a power generation sense, at almost all times. There wouldn't be enough energy to extract at high fan speeds, due to low intake volume, and the fan wouldn't extract enough of the available energy at low fan speeds, due to the low generator armature speed.

Half the displacement (4 cycle inducts only half the displacement per revolution), minus the manifold vacuum percentage of atmospheric pressure, times the RPM.

.5DXvac/ATPXRPM=volume of air flow.

750 CC (per revolution inducted) at 550 RPM at 22 inches of manifold vacuum which leaves 8 inches available (assumption). That is assuming atmospheric pressure is 28 inches, slightly low but easy to calculate.

Manifold vacuum at 22 inches would leave 8 inches of available atmospheric pressure for induction or about 25%, of the volume if it was unrestricted.

46 cubic inches---X---550 RPM---X25% of atmospheric pressure volume of air.

That works out to 6325 cubic inches of air at idle or 3.66 cubic feet of air.

Christ, I am not engineer by any stretch of the imagination, but if the power is so low then conversely it would take very little power to boost the engine to 1 atmosphere pressure. I think the quote was over 200 Amps for the power necessary to provide boost. It would seem to me that you should be able to get much more than .0005 out of the same system.

Basically the basis of my thought was the fact that most engines operate at a certain average of manifold vacuum.

I was not talking about an propeller of any type. I was talking about a positive displacement pump that would have to rotate if any air passed through it.

It could not be reciprocating and would by design only restrict the air available to the engine in the same way a throttle plate does.

That is a loss that already exists.

Exhaust heat already exists.

Both do represent energy losses, but in the same way that aero drag on your vehicle represents an existing energy loss.

Please do not consider this as any rebuttal to any of you who are interested in this thread and have taken there precious time to post a response.

My line of thinking (which could certainly be miles off, merely conceptual) is if you could extract the energy lost due to throttle plate restrictions which are always there, then you could use that recaptured energy to provide boost when necessary. As long as the boost was very limited it would be an energy neutral condition.

Now it is certain that you could never extract the same energy you would need to apply to reverse the situation and provide boost to the engine, but that expenditure would only be a very small amount of the total running time of the same engine.

A decent analogy would be the way we tested tire-wheel combinations on the car when we had a vibration problem that did not respond to balancing.

We took one of the small angle grinders, backed the brake pads off the front rotors and used the angle grinder to spin the wheel up to a high speed. The angle grinder produced very little power. You could hold the disc and pull the trigger and it would not spin over.
However that same low power source would spin a wheel-tire assembly up to close to 100 MPH. That's enough energy to rip your arm off if you grabbed that rotating tire.

My calculation looks a lot lower that Tom's. I would assume he figured the air going into the engine would be at atmospheric pressure, when the volume represented only 25% of what it would be if the throttle was wide open.

Not sure of anything, just thinking out loud, no need to slam me as a moron.

We do know how much power it takes to boost the sir into the engine. I would think you could extract about a third of that energy with a proper setup.

I'll show a picture of my small demo prototype on a variable displacement, positive displacement pump, that is what I would use in this theoretical application if you like.

Its the basis of my pending patent.

What I really like about the electric supercharger is that it does not add to the engines loads unless it is being used. Even then it is using battery energy, which could be recovered when you were in DFCO or at other times when it would not be a direct cost of operation all the time.

regards
Mech

In all this discussion one thing has not been addressed. The electricity to run the supercharger has to be generated by the alternator.
With the less than 100% efficiency of both the alternator and the supercharger motor you end up with a net loss of energy.

In my scenario, I would have the fan be on it's own circuit running off a deep cycle battery stowed in the trunk.