Increases in automotive charging efficiency?

[jtanguay]

Hi everyone

I've really been pondering the idea of how to use a permanent magnet alternator in a car. I like the idea of not having to excite the magnetic field so that no external input is required to start cranking out juice. No brushes is pretty cool too!

The next thing is that with the extra magnetic flux of the high strength neo's, the alternator pulley could be increased in size to reduce it's rotation speed. Some of you might not think that it is much, but think again. When your motor is spinning at 6k rpm, the alternator is spinning at around 18k rpm!!! With that bulky rotating mass of iron is spinning you better believe it affects the car. With a slower spinning alternator it would really wake up the cars acceleration etc. It has already been proven to be the failure point of VW diesel engines (older 1.9 aaz) that would give out after about 200,000km from the stress of the alternator spinning mass coming to a dead stop because diesel engines fall to idle rpm almost instantly from the high compression.

But now onto the actual charging mechanism. I've thought about using mosfet's but not sure. It would need to be efficient yet robust. It has to handle quite a bit of amps too. SCR's maybe? I've also thought about converting the whole car to run off of three phase power but that would be a regulating nightmare lol. At least the car wouldn't really rust.

Then I thought about even converting the alternator into a bipolar bedini charger. Is that crazy or what? Would a large capacitor and scr dump be enough to supply the cars battery and onboard components? Would the alternator need to be converted to monopole?

I think this would be a great way to harvest some high energy spikes for the plasma spark ignition

[dingo]

nice ! i like all those ideas...ive been circling that whole arena for some time, but never came up with anything concrete...so im all ears !!

[jtanguay]

nice ! i like all those ideas...ive been circling that whole arena for some time, but never came up with anything concrete...so im all ears !!

I was thinking that the current automotive alternator regulator could be used to trigger mosfets to allow the current to flow when voltage drops below 14-15v but then leaves the 3 windings connected when not charging to reduce drag on the core?

Ideally it would be nice to use Tesla's method of extracting DC from AC. If that could be done it would be a truly solid state setup and be virtually fail proof (just the bushings but if we get the alternator to spin slower, then their lifespan will be greatly increased)

Some car manufacturers are going for an alternator/starter combo. I really like that idea. For a non electronic version of a three phase motor switches could be used to alternate the dc current. Of course an electronic circuit would be more efficient, but would be a failure point. It would be nice to eliminate the inefficient starter motor with those really thick gauge wires going to them that always corrode.

[Sun Fusion]

I think your idea will work, but how do i install it in mine. I don't know, can any mechanic help me?

[Michelinho]

Hi jtanguay,

Some car manufacturers are going for an alternator/starter combo. I really like that idea. For a non electronic version of a three phase motor switches could be used to alternate the dc current. Of course an electronic circuit would be more efficient, but would be a failure point. It would be nice to eliminate the inefficient starter motor with those really thick gauge wires going to them that always corrode.

If I remember well, those alternator/starter combos worked very well on papers. But in real life, when a bearing seizes on a regular alternator, the belt slips. An alternator/stater combo unit is gear driven and when a bearing seizes, the gear on the unit breaks or the gear breaks a few teeth on the ring gear or the gear breaks the bellhousing or it destroys the combo unit and if not lucky, many or all of the above.

Technologies have come a long way and components last a long time nowadays, I still prefer a belt on my alternator.

Hope this helps,

Michel

[jtanguay]

Hi jtanguay,



If I remember well, those alternator/starter combos worked very well on papers. But in real life, when a bearing seizes on a regular alternator, the belt slips. An alternator/stater combo unit is gear driven and when a bearing seizes, the gear on the unit breaks or the gear breaks a few teeth on the ring gear or the gear breaks the bellhousing or it destroys the combo unit and if not lucky, many or all of the above.

Technologies have come a long way and components last a long time nowadays, I still prefer a belt on my alternator.

Hope this helps,

Michel

But the whole problem is that the current alternator configuration spins way too fast. We want a high torque low speed alternator/motor setup. The pulley on the alternator would need to be increased to the size of the pulley on the a/c compressor. A different belt would need to be used and hopefully the tensioner could take the rest of the slack.

The stator would need to be re-wound with thinner gauge wire to make this work. Possibly even winding bifilar in parallel to increase the amperage capacity but keeping the rpms required nice and low. Off the shelf components could be had from the existing permanent magnet alternators used for wind and hydro generation. They can make good power even from 130 rpm. Nice and slow. The slower the alternator spins, the less precise the balancing needs to be so you could make your own permanent magnet rotor with neo's.

Now if A/C power could be derived from DC power with coils only, then we'd be in business for a bullet proof design. But so far I think regular switches would be the only mechanical solution. Don't mind electronics, but I see it as a failure point.

The main goal of this idea is increase the efficiency of charging but at the same time increase responsiveness of the engine by reducing the parasitic drag from the accessory belt. Good old V belts were good in that department because they would have some give. Serp belts pretty much hang on no matter what unless the tensioner is going. But ideally the whole ICE should be thrown to the curb for an electric motor... if only I had the $$$

[Neight]

Ok, i could be totally off base here, but I had an idea pop in my head while reading the previous two posts....
what about magnetic cogging for the linkage between the alternator and motor? It would reduce the friction and heat of the system, and if something did break, there would be no actual parts connected, so it possibly wouldn't break everything as in an actual gearing system.
again, I just learned about magnetic cogging the other day, so I may not know enough about it to know why it wouldn't work, but it seems like a great solution for what you guys are talking about!

excellent post btw, some great ideas in here!
thanks
N8

[Michelinho]

Increases in automotive charging efficiency?

The charging system on a car is not really consuming too many HPs. True that an alternator uses 5 to 7 HPs at full charging rate but it is hardly ever in that range of output. Someone can get away with a larger drive pulley if he doesn't have a 2000 watts sound system installed.

A module feeding the field of the alternator varying in strength according to driver's inputs could improve slightly fuel consumption (I here suppose that this is not being done already by car makers). Drop the field strength on acceleration and raise it on deceleration. The regenerative charging done in electric propulsion is similar in effect.

Take care,

Michel

[jtanguay]

But if using neo magnets instead it would increase the efficiency. Alternators are made to fail by design. They spin at 3 times the engine rpm, and have those pesky brushes to fail. Thicker wires are used to decrease the likelihood of defects in production, but require high rpm's to get the current flowing from the relatively low field of the electromagnet rotor. If thinner wires were used like on the wind generation PMA's then the alternator could spin slower and really increase its lifespan.

Once you start getting deeper into the possibilities, it's amazing. You'd need a large cap or a bank of them but you could have the engine turn off when at a stop light, and then have the alternator crank out the first 5 hp or so to get the car rolling and start the engine up. Instant 'hybrid'. Regen braking would really be good too with a bank of caps to capture all that big energy rush. It could then be used as a sort of 'turbo boost' for the motor.

The only major problem here is designing the system to charge up the battery (or batteries) without making them explode from all the power flowing in. Maybe hook it up to a cabin air ionizer when the battery is full?

[clueless]

I have two observations/questions

1.) I know that cars have voltage regulators built in the alternators usually; why couldn't you have a clutch on the alternator pulley work like fan clutches does. At a preset temp they freewheel seems to me an alternator could work the same way.
2.) Since most of us are looking for ways to store excess energy (solar/wind) in batteries why not tap into your car's charging system. It could be as simple as a couple extra batteries in the trunk and hooking it up via the adapters in the dash. Seems to me that way as you are driving you are storing free energy ( so to speak) I assume the extra load would decrease gas mileage some.
It is something I plan to try in the future.
-RG

[WeThePeople]

First, you can use brushless alternators that have a stationary energizer coil on a common core with the rotory coil of the rotor to eliminate that argument.

But more importantly, is that having a magnet based alternator's rotor,
is like having an engine with no regulating mechanism like a carburetor.

Full blast, all the time, period.

By the time your done wasting the extra in energy,
in the form of wasted heat from a charge controller,
I fail to see the gain here...

I do agree though.

Brushes should have been abolished long ago,
in favour of brushless induction-excitation designs.

You won't find brushes in any commercial app., bus, trucker alternator.

But regulating the output via the excitation coil IS (already) the most efficient,
the tri-stator coils run cooler, as does the rectification bridge set also.

The only condition I can see an advantage to for a Magna-Stator app.,
is if you have storage that clearly outsizes the continuous output it makes.

Or the most efficient portable charger utilizing a weed-wacker's motor or something.

[jtanguay]

First, you can use brushless alternators that have a stationary energizer coil on a common core with the rotory coil of the rotor to eliminate that argument.

But more importantly, is that having a magnet based alternator's rotor,
is like having an engine with no regulating mechanism like a carburetor.

Full blast, all the time, period.

By the time your done wasting the extra in energy,
in the form of wasted heat from a charge controller,
I fail to see the gain here...

I do agree though.

Brushes should have been abolished long ago,
in favour of brushless induction-excitation designs.

You won't find brushes in any commercial app., bus, trucker alternator.

But regulating the output via the excitation coil IS (already) the most efficient,
the tri-stator coils run cooler, as does the rectification bridge set also.

The only condition I can see an advantage to for a Magna-Stator app.,
is if you have storage that clearly outsizes the continuous output it makes.

Or the most efficient portable charger utilizing a weed-wacker's motor or something.

I still think you're wrong there. If part of the alternators charging power has to go to creating its own magnetic field, then that is a loss. The regulating mechanism will be the toughest thing to build but might be worth it. I'm starting to believe that a toroid transformer will be the best solution. It would reduce the necessary diodes to 4, unless mosfets were used. There will be no drag on the alternator if it is not in charging mode. A set of mosfets could be pulsed to achieve a steady voltage. That is where the electronics come into play.

What would really make this interesting, would be to incorporate the whole unit right into the flywheel. That way there is even less to go wrong. Some machining of the flywheel to accept the magnets, and then bedini style 10 coiler placed around.. but that would require extensive modification to the bellhousing. So us lay folk will have to stick to the more simpler methods.

[HairBear]

This idea is not new... Alternators have been used as magnetic generators for years. There are a plethora if kits available on the net to make such a device.

There aren't any gains in efficiency, thanks to Lenz's law. The more current flow the more drag... It doesn't matter if you generate the magnetism or use magnets, the overall result is still the same.

Permanent Magnet Alternators

http://www.windenergy.nl/website/fil...HowItWorks.pdf

Since a typical automobile produces a good amount of heat, why not ponder the use of thermocouples or some other ingenious way to convert the all the heat that is wasted?