I came into this forem with the thought that high
voltage systems would be the way to go and actualy did
several design looking at several brushless technologies
to try to come up with a more cost effective design.
I felt that you could get more battery life (longer
range) by using higher voltage. After contacting a
number of different Battery manufacturers (Lead acid,
sealed lead acid, lead calcium, NiMh, and Lithium
Polimer) I came to one conclusion. It doesn't matter if
you connect he batteries in series for higher voltage
or parrallel for higher current capacity The
Watts/KG are the same you are going to need just as many
batteries no matter how there connected. It is still true
also that DC brushed motor offer the least costly
technology for electric propulsion. The EV guys who are
spending a lot of money on this research have come to the
same conclusion. Thats why International Rectifier,
GE, ABB,Siemans and many other semi conductor
manufacturers are no either working on or have comeout with LOW
COST high current chips that operate on less than 100
Volts. You can now buy for very little money high
current controls that will develop up to 20 HP for well
under $1000. I am presently testing a Full H bridge
controller that will run on 24-72 Volts and provide 200 amps
on continuous current. this control provides solid
state reversing AND regeneration and cost between $600
and $800<br>That means one can now put a 10 HP Motor
and controller in their boat to replace there 30 Hp
gasoline engine and do it for less than $3000 including
motor. And they can charge there batteries while under
sail. <br> Unfortunatly DC Brushles and AC propulsion
units are still far more costly than that. it's a
matter of economics.
