Yes another alternator post

[some_other_dave]

Originally Posted by Christ

If you want to look into something like this, the best info I can offer is MOTORCYCLE engines. They don't use a permanent magnet, that I'm aware of, but they do have an internal alternator with no belt drive.

My understanding is that a lot of them deliver their full charge, all the time. "Voltage regulation" is done with a big resistor and a shunt to ground.

-soD

[Christ]

They do. Most are not regulated, that I'm aware of. I simply suggested it so that the OP would have an idea of what to do in order to make it work for a standard engine.

Here's why it always charges, and doesn't involve a voltage regulator: It's a Generator. Run the head light all the time, and it eats up the extra voltage, so there is no danger of overvolting your electrical system.

Using a generator in place of an alternator is not an efficient method, I know. That's why I suggested that OP get ideas from looking at the design, not actually implement the use of a motorcycle's generator in his own plan.

[Vwbeamer]

What would be ideal is to have an alternator that disconnects during load,but reconnects while braking. regenerative braking of sorts.

You could increase the rpm the alternator is driven at,so it runs at a high load during braking.

You could simply use a relay hooked to the alternator output to make an electrical connection when the brake is applied.

Maybe add a dash switch to activate the alternator also when coasting down hill.

Just some thoughts.

My experience with motors on dyno's, is that alternators and pulley use very little power when not electrically loaded.

I plan to try this on my 914.

[whitewiz]

I think there is a lot of potential in efficient ECU programming. A/C and Alternator use could be suspended during acceleration and exaggerated during braking. I always wondered why there was no high pressure storage for A/C. I also wonder why there is no standard ECU.

[Christ]

Newer cars with true climate control have very advanced computational systems that control the a/c for you. They were introduced as step toward making sure the driver had less things to play with, not so much toward efficiency.

I like the idea of not providing a field to the alternator unless you're braking, except it doesn't work out quite right for those of us who do alot of driving at night, and especially on the highway. There would have to be a lower limit switch as well, so that if voltage dipped too low, it would kick on in sort of a "save mode" so that deep-cycling the battery didn't occur.

I kind of rather like the idea of using the battery in a pulse and glide sense as well, where you discharge it, then recharge it, instead of just keeping it topped off.

[rmay635703]

A bit off topic but if you really want to get rid of alternator drag but still have your car make electricity to charge the battery a bunch of these might be a good idea

Taihuaxing Thermoelectric Power Module

You would still need to charge your battery by the looks but at least your ignition and possibly lights could be run off the heat of your engine being cooled by the outside air. This would only charge the battery if you have enough modules and a long enough drive time but I think it is a step in the right direction, now if I could figure out a way of making this produce usable power for an EV?

[beatr911]

I like the sheet thermocouple idea. Put it on the side of the engine, radiator, maybe the exhaust to just go alternatorless. Any idea on pricing, availability and durability of these gems?