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US Army Unveils Hybrid-Electric Propulsion System
Gary writes to mention that the U.S. Army recently unveiled a new hybrid-electric propulsion system for use in a new line of manned ground vehicles (MGVs). The new line will have eight different variants, all using the same chassis. The unique feature of the new MGVs is that the traditional engine has been decoupled from the drive train and is used only to recharge the battery and power other systems within the vehicle.
-b.
M1 Abrams tanks have a turbine engine that is hooked directly into a generator which powers a 1500 hp (1119 kW) electric motor
Let me set this straight.
Unless the Army has completely refitted it's tanks, the above is only partly true. It does have a turbine engine and does produce 1500hp, but it's not an electric motor. Has a plain old drive train that goes into the rear sprockets. There are no massive batteries to store the charge (IIRC it has 8 12v batteries).
What makes these things so darn quiet (for a tank, you hear the treads clanking before the engine when it's moving) is that the exhaust is directed up at about a 45 degree angle so the majority of the sound doesn't echo off anything. Of course, that gives it a massive thermal signature, but at the time of it's design, soviet block tanks were not using thermal sites.
This is speaking from experience, I spent 4 years as an M1A1 tank crew member (19k) and prepped the engine(power pack)for removal more than once. There is no greater rush than firing the 120mm main gun at a target 2100m away and/or moving 68 tons of combat steel over any terrain.
Hope this helps, I don't see any "green tanks" in the future and they get horrible gas mileage - a full tank of 504.4 gallons gives you about 200 miles over flat terrain @ 35mph.
Good judgment comes from experience, and a lot of that comes from bad judgment.
The use of all-electric drive can provide some interesting opportunities for advanced systems such as traction control. By placing multiple, smaller drive motors at each wheel, power can be directed optimally for terrain conditions. No complex mechanical equipment is needed as the algorithms can be implemented completely in software.
The other advantage can be the ability to optimize the IC engine for changes in the fuel available without screwing around with the entire drivetrain. Heck, they can make the IC portion modular and, if the economics of fuel sources change, just pop in the appropriate engine.
Have gnu, will travel.
This refers to the UD effort that predates FCS by many years:
l
/ humvee.html
http://www.angelfire.com/art/enchanter/hybrid.htm
Ralph Zumbro, Author of "Tank Sergeant", writes about the Hybrid drive M113 that United Defence have built:-
"Phil, The one I was in, and it may be the only one, is state of the art. They steer it with a Bradley gunner's control and it will run for an hour at 30mph on two batteries which are in boxes sized approximately 18"x36"x48". Then a standard issue genset cuts in. The motors are rated at 250 hp each and are oil cooled. It is weird to see a 3 inch diameter drive shaft coming out of a motor the size of a 5 gallon can.
The rubber tracks are soundless, and they've got 2500 miles on them with very little wear showing. That adds up to a VERY quiet vehicle for recon work. Put electric motors, rubber tracks and a two man turret with a 30mm gatling weapon on a standard 113 hull and you've got a recon Tankita.
I mentioned to the people at United Defense that not needing air for the engine made the vehicle capable of running around UNDER water and was told that that had been thought of. That means that you could add enough armor to stop larger weapons, as long as you don't compromise the mobility."
More links:
http://www.defensetech.org/archives/002338.html
Hybrid M113
http://www.youtube.com/watch?v=RbWbkOkTydk
Hybrid HMMWV
http://www.evworld.com/archives/conferences/evs14
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