Homemade Generator Question

 

  I'm working on a homemade generator, built from a large marine battery,
1500W AC inverter, and an old truck alternator rigged to a small engine. I
got the rig going the other day and it worked quite well, but the problem is
that the alternator is not regulated. With no load on the inverter, and the
engine revved up, the output soars past the limit of the inverter and causes
a warning light to come on.
  Is there any way to regulate the output of the alternator? Well, I know
it's possible, but can anyone point me to some schematics or something?
  Thanks for any advice.

 

The Arrl handbook has a solidstate regulator project, at least it did years ago.
I used it in a honda civic for years with out any
trouble.

Cheers

 



Well, you could go to either the truck you pulled the alternator out of,
or an auto junkyard, or an auto parts store, and probably get a
compatible regulator rather easily that way. Building one isn't too hard
if you know how, but getting from not knowing how to knowing how is a
journey better taken with your own copy of _The Art_of_Electronics_ in
hand, and ideally with someone else who knows what's what to give you a
hand once in a while, rather than through newsgroup postings. Having a
project in mind can make the learning process easier...

An ideal setup for this might be slightly different than the off the
shelf auto regulator - one that would slow the engine down as well as
reduce the field current (when voltage went up) and speed up as well as
increase field current (when voltage went down).

--
Cats, coffee, chocolate...vices to live by

 



If your intention is to run the inverter and not to charge batteries
directly then an alternator with a built-in voltage would work well.  I'm
using a GM Delco 65 amp alternator (such as what they show here)
http://theepicenter.com/tow02077.html
connected to an 85 Ah deep cycle battery.  This feeds the inverter.  Without
the battery in the circuit the voltage can go well over the maximum for the
inverter but never seems to rise above 14.5 volts with the battery in there.
Since I am only running it to charge batteries most of the time (charger
plugged into the inverter) I am using a 700 watt inverter.  But since I also
have the battery I can attach another 800 watt inverter and run loads up to
at least 1300 watts for a limited time.  I have not tried more than 1300
watts yet but theoretically I should be able to get about 1600 or more out
of it.  The built-in voltage regulator so far seems to do a good job of
keeping the battery topped-off without overcharging it.

 

Doesn't a marine battery charge different than a car battery. and if you use
the battery and inverter without the motor running and than start the motor
to recharge it dumps to much power in to the marine battery. I don't know
for sure, This is what is keeping me from building this unit.

Craig


battery,

problem

Without