On Saturday, 19 May 2018 20:51:51 UTC+1, Johnny B Good wrote:
On Sat, 19 May 2018 09:58:43 -0700, tabbypurr wrote:
On Friday, 18 May 2018 22:45:49 UTC+1, Johnny B Good wrote:

The rectifier volt drops for even the lower 200 volt alternator case
will now only represent a mere 1% loss (the 230/240 inverter genset's
400vdc alternator output reduces this to a 0.5% loss). The inverter
losses are unlikely to exceed 2 or 3 % making such a genset a whole lot
more efficient than even a simple basic single phase 230/120vac 50/60
Hz alternator driven directly at 3000/3600 rpm let alone a
franken-genset comprised of car alternator and 12v to 120/230v inverter
box.

This, BTW, was a heads up for any of the more ambitious DIY
enthusiasts
monitoring this thread who might happen to be contemplating homebrewing
their own inverter genset 'on the cheap'. :-)

of course that isn't true if you let the alternator produce more than
12v

If you're prepared to run the alternator fast enough and replace/modify
the regulator, you could probably get away with letting it output 28 or
maybe even 42 volts (assuming you limit the excitation voltage source to
14v to prevent burning out the field coil). The PIV rating of the
rectifier pack is probably 200v or more which should leave some margin
for voltage spikes.

However, you might do better to start with a 28v truck alternator and
double up to 56 volts to feed a 48v inverter module (perhaps one

sure but making something on the cheap makes oh look, I have an alternator sat in the garage, let's use it.


body. Somehow or other, it just seems so much easier to simply[1] spend
99 quid on a Lidl Parkside PGI 1200 B2 inverter genset and have done with
it. :-)

today yes. Gennies used to cost far more. Your £99 job won't last long though.



Indeed, the amount of 'interesting bargains' in electronic tech and
genset rarities seem to have become vanishingly rarified over the past
few years in both Aldi and Lidl stores. There was a time when I used to
look forward to browsing the non-food sections whilst SWIMBI did the
weekly shop but not for the past two or three years now. :-(

ditto, I seldom bother now.


NT