
On Tue, Jun 14, 2016 at 03:15:07PM -0400, Alvin Starr via talk wrote:
It is possible. Not saying its so, but if the new cars can handle variable voltage and the old cars are fixed voltage then it could make sense to upgrade the lines in advance of removing all the old cars. Then when all the old cars are gone upgrade the system voltage.
Its not that you would need to put in heaver lines for higher voltage but a close to 50% increase in voltage may make you replace all the insulators that were rated for 600V with ones rates for 750V.
I would expect the motors on the new cars would be based on AC motors which is the predominant motor type in electric automobiles but with something as big as a train the rules for motor choice may be different. With AC motors the control electronics would have to handle the voltage variations but its doable.
Well certainly electric cars and hybrids all use AC motors with DC storage and generate the desired AC. I would be surprised if the new streetcars don't do the same. So given that, it is quite possible that they may in fact be able to handle a range of voltages. Of course since they probably need a bit of onboard battery capacity, that could be a bit more complicated depending on how they choose to deal with the incoming DC power. -- Len Sorensen