An electro-mechanical powertrain includes a pair of motor/generator units
that are interconnected with a transmission output shaft through planetary
gear mechanisms. One of the motor/generator units continuously supplies
power to a power takeoff unit, which operates accessory devices and
supplies power to a transmission output shaft. The second motor/generator
unit continuously transmits power to a transmission output shaft except
during a ratio interchange. A selectively engageable clutch is operable to
connect the first motor/generator unit with the transmission output shaft
during the ratio interchange when the second motor/generator unit is
disconnected therefrom. Both of the motor/generator units are supplied
with power by a fuel cell prime mover through an electronic control unit.
