Current boat has 110AC air conditioners and some small appliances but the rest of the systems are on 12VDC. Genset ate a jellyfish and has to be replaced, so I'm working out options to upgrade/change the electrical system. Converting the whole boat to 24VDC is probably not doable as that seriously limits the places you can get replacement parts.
I've found a DC Generator with a ~200Amp output @ 28VDC that I need to convert down to 14VDC to charge the house batteries.
How do you do that efficiently at such high amperage? Lots of parts out there, but they are typically 5A or less and running them in parallel is just not a very good idea.
Rest of the boat is on 12V as well, trying to use 24VDC to halve the current from the Genset to the battery bank and power panel.
Wondering aloud if it makes more sense to go with alternator instead of a Generator and convert from AC -> DC closer to the battery bank as that would cut the current flow for the longest part of the wire by 6-10x. The problem with AC is the speed of the engine affects the 60Hz portion of the equation. I've considered adding one alternator per Diesel but can't figure out how to make that work since the RPMs of the engines that run the props are subject to change based upon propulsion needs and getting reliable 60Hz out of that setup seems nearly impossible. And combining the 2 AC alternators when the motor speeds can't be synced seems like inviting disaster.
Any ideas how to solve this kind of problem without just replacing the existing generator with another?
============ Answers to some questions in the coments/answers =======
- Old genset was 6500Watts @ 110VAC
- 200 Amps @ 28VDC to provide about 400 Amps @ 12VDC which is only 4800 Watts but sufficient for the aircon load
- With a fully DC system, I'd be feeding a larger Inverter to run the Aircon from the generated DC or the batteries.