A first hybrid-electric tracked armored vehicle developed by the U.S.
Army’s National Automotive Center and BAE Systems (formerly United
Defense) was the hybrid-drive 15-ton M-113 prototype. The vehicle's
battery power was used to provide transient power needs, on
acceleration, steering and climbing. When stationary, the vehicle can
generate about 200 kilowatts of electricity and function as an
auxiliary power unit.
Relative to conventionally powered M113A3 the hybrid
powered vehicle would produce about 500 horsepower in acceleration,
versus only 275 horsepower for the most powerful M113A3. The vehicle
developed the augmented power by supplementing the conventional
engine’s generated power with the energy stored in the battery pack.
The batteries stored the energy produced when the brakes was applied.
of the modern armored vehicles development programs, including the US
Army FCS, British FRES, French
BOA EBRC and Swedish SEP are
based on HED technologies. Most programs are evaluating technology
demonstrators prior to final decision on the type and configuration of
the automotive system. Among these demonstrators are
AHED, developed by General
Dynamics, SEP, produced by BAE
Systems land Systems, and TTS, produced by BAE Systems (formerly UDLP).
AHED, an 8x8 wheeled vehicle has been demonstrated following several
years of field testing, accumulating over 4,200 km of road and
cross-country testing. It is currently undergoing testing in support
of the British MOD FRES evaluation phase. The Swedish SEP program
includes both tracked and wheeled versions. The wheeled version,
vehicle has three axles and uses 6x6 drives. The vehicle uses two
engines driving an electric transmission, powering each wheel by a 100
kW maximum power permanent magnet, in-hub electric motors. The motors
are fitted with a two speed reduction gear. This design offers high
redundancy and survivability when operating in combat conditions.
tracked version of SEP is fitted with special rubber bandtracks
(already used with Bv206 articulated carriers) rather than
conventional steel link tracks. These tracks are lighter, quieter and
have a operational life of about twice that of an equivalent steel
linked track. The new bandtracks have a lower rolling resistance and
are operating more efficiently with the electric transmission systems,
yielding higher fuel efficiency. Another unique design feature is the
underframe mounted suspension. This spaced outer layer gives enhanced
protection against mines. The SEP vehicle can withstand a 7 kilogram
TNT explosion under a track.
Similar techniques are evaluated for the
Transformation Technology Demonstrator (TTD), developed by BAE
Systems. This demonstrator uses hybrid electric drive combines battery
power with a 250hp diesel generator to deliver 450hp instantaneously,
enabling faster acceleration than any existing combat vehicle. When
used in stealth mode, the TTD has a 10-mile range on battery power,
producing silent operation. When stationary, the TTD can stand "silent
watch" for more than 30 hours – both features will be of significant
value for Future Combat Systems (FCS) applications. The TTD is
designed for C-130 transportability and could travel up to 600 miles
without refueling. Its band track provides three to five times the
current track durability, significantly reduces noise and vibration,
improves the ride and requires little or no maintenance. The company
cooperated with General Dynamics in the development of a
hybrid-electric FCS-W (Future Combat Systems— Wheeled) demonstrator
which can travel 5 miles per hour for 30 minutes on level ground using
only stored electric power.
HED automotive technology is used in robotic ground vehicles, an
example was the Spinner 6x6 HED powered Unmanned Ground Combat Vehicle
(UGCV), which demonstrated up to 14 days missions and 450km range
without refueling. The vehicle is powered by a 60Kw turnine, driving
an electrical generator, feeding liquid cooled 30Kw hub UQM motors.
The vehicle uses Lithium Ion SAFT battery to deliver up to 18 Kw/hour
for silent operation.