Multi Genset DE system

Problem: 25ton vessel needs to do 10+kts up stream in rivers but also navigate canals at 4kts. Going slow with performance and economy is a major part of the problem. In an ideal world the Diesel-Electric Propulsion will be via two high voltage generators powering one a heavy-duty Electric variable speed motor turning a 60x60cm prop in a steerable Motor-propeller pod. Domestic power will be from a power transformer/conditioner and a inverter(s). Slow speed will be achieved with the smaller of the two gensets while high speed will be achieved with both in operation.
What company can provide this solution?

 

The concept is certainly feasible. I doubt you will find all the parts ready to install as a complete package though; you will probably end up buying the motor pod, generators, and controllers from at least three different companies. I would start by getting some estimate of the power needed to push your 25t hull at 4 and 10 knots, either experimentally if the boat's already built or by CFD if it's still on paper. Once you know your power requirements it will be easier to narrow down your equipment choices.

 

Matt
Thanks for the reply.
I have found the drive motor and gen sets from Fischer-Panda.
They are very pricy and they have a hard time with the two different size gen's. on the same grid? Forget transforming the 430 vdc to any useable domestic power other than a small 24vdc alt for the starting battery.

Typically anybodies TDI 100hp or 76kw diesel on a 2:1 trans will do the trick for the high speed. As for as the low speed, 4 knots at tick over. As one navigates a twisty canal it is a constant of Nuetral, reverse and forward at tickover. The turbo gets all gunked up after awhile and motor burns a lot of oil. The transformers, conditioners and controls seem to be the hard part for drive and domestic power. The idea of four gensets to accomplish one task is not what I have in mind.

 

Try Glacierbay.
I am sure they can design a system that suits your needs, unless you know a lot about this stuff and be able to design one yourself.

http://www.glacierbay.com/ossa_powerlite.asp
http://www.ossapowerlite.com/

These threads have a lot of generic information about diesel electric propulsion:

http://boatdesign.net/forums/showthread.php?t=676
http://boatdesign.net/forums/showthread.php?t=9310&page=2&highlight=diesel electric

 

Here's a thought, I'm thinking to have my prop push on a thrust brg so as my drive system/s can be separate.
I'm thinking for most sea or strait forward / reverse work I have the main diesel engine engaged -- probably via a solid simple dogging device -- and for those times when I will be poking around up rivers / canals & the like, I revert to electric drive to give the slow control . How ?
Well shoot holes in anything I say as it's all just ideas at this stage, only I can't see why it couldn't be done.
Ok, so I've come to the rivers tight spot & the diesel is just too fast even at idle. I dog out the engine and dog in - or hit the button - that connects the DC electric drive to the prop shaft.
If my gen set runs off the main engine, I ajust the revs and away I go. [ yeah I think that extended use of this system would glug up the diesel as it's not working enough to be healthy !]
Otherwise my on demand small eficient diesel gen set kicks in and powers the now electric drive -- switch off the main engine . the gen set would charge batterys, heat water, run refrigeration & or house power etc . I'm saying it would work & so not "oil up " or "gunk up", as the typical diesel does when not used efficently. [ look at the exhaust of yachts who run their main engines just to charge the batterys & run the fridge compressor, a blue haze !! , big engine [ in relation to the load ] not working enough - or rather, ineficiently ]

4knts wouldn't require too much power & the advantages of infinately vairiable forward or reverse [ instantly - no crunching of gears!] not to mention quietly, -- for small use your batterys would suffice, say getting on & off a mooring [ as in my case, as a yacht] the fisher panda gen set would be far quieter than your main eh !?.
I think this sounds a lot cheaper than [ maybe that's not an issue ?] what you're proposing and a lot less electronics .
I like the idea of being able to go back to diesel power - just dog in the main - should anything go pop - poof [ "sounds" of electrical death ! - vs, clank clank clunk squeeeelll bang -- diesel death !! ha ha ha ]
My old girl would go without any electics at all -- hand , tow, sail start all ok
[ decompresion levers, just spin her & drop the levers ]
Me thinks you're a bit more up market than that but can't see why it wouldn't work for you .
Oh, you can hook in the Dc engine - now alternator [ when driven]- while your main is engaged to keep the engine efficient [ & run the house power] between the "10 +knts and 4knts" canal work if required .

Some controlable pitch props systems have a PTO off of the gear box, with the engine in neutral & shut down [ I don't know if this is possible ] maybe the electric drive could be conected through the PTO giving you all sorts of combinations with both diesel & electric drive !?. [ Thinks --another electric start --- uuuum, It'd work with my old girl ! ]
Sorry, obviously got too much time on my hands .
Globaldude.

 

Interesting idea, globaldude. You might take a look at diesel-electric submarines, many of which have a mechanism for switching powerplants very similar to what you describe.

 

Woa !!! , that was a fast reply !!.
Yeah it's not rocket sicence but seems to me the more drive systems you have [ can read - trouble or backup ] the better .
I should look at the sub systems for changing drive as my " dogging" seems a bit agricultural ! eh

 

You're turning Canadian
The idea of a dog to engage/disengage isn't actually that bad. Stick-shift cars have one of these for each gear. Many outboards and sterndrives have one in the lower unit. The thrust bearing, of course, is a given or else you will destroy your transmission or motor in seconds.

 

I don't know about Canadian, but " eh !" is typical Kiwi, as is " bloody hot" or bloody angry" etc. I've seen Canadians a bit puzzeled when first encountering that .
When we finaly set off, we want to do the pacific rim & I'm looking forward to seeing Canada as it seems, from talking to others, we have quite a lot in common.
yeah there's not a lot to go wrong with a couple of dogs !.