Gene,
Just completed
reading Electric Propulsion For Boats
by Charles Mathys, ISBN1-892216-49-3. He documents his experiments with
developing efficient 1 to 3 HP DC and AC PWM 24 to 48 volt electric motor
marine propulsion systems. He provides circuit diagrams with safety
features, performance results, and estimated costs for the various options.
Surprisingly, it is pretty easy to build a 24 to 48 volt AC 2 or 3 HP system
that can exhibit as much as ~20% more efficiency than a comparable costing PWM
series-wound DC system. He steered clear of DC permanent magnet motors
(PMM) due to high cost and limited availability (he expects that this motor
would have near the same efficiency as the comparable AC system). I
believe this last observation is no longer true as there is a web site now
offering a variety of PMM motors and commercial controllers (which have the
safeguards built in). I would highly recommend this book if you want to
get a good education of options for your electrical power system.
R/J2
Respectfully,
Jay K. Jeffries
Andros Is., Bahamas
It is the mark of an educated mind to be able to
entertain a thought without accepting it.
- Aristotle
From: owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org]
On Behalf Of Mark Roberts - Harbortronics
Sent: Tuesday, February 06, 2007
7:50 PM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST]
Interesting link to a PWM
Well, it's a start. This is a
fairly classic H-bridge driver circuit topology, but the devil is always in the
details! A kit like this will be fairly minimalistic, missing
protection circuits, and presumes you will have the knowledge, ability,
and resources that are required to make it into a bulletproof motor driver. IMHO
the average PSubber is going to have enough on their hands dealing with
mechanical issues, and really ought to just buy the electronics... there really
isn't a lot of cost benefit to making your own stuff anymore. There are lots of
companies that have tried and tested motor controllers...
----- Original Message -----
Sent: Tuesday, February 06, 2007 3:58 PM
Subject: [PSUBS-MAILIST] Interesting link to a PWM
Can we get some feedback
from someone who works with electronics regularly as to whether this will be a
start for a custom made answer to efficiently driving psubs motors?
I found this on an ROV
yahoo group