The electrically variable transmission family of the present invention
provides low-content, low-cost electrically variable transmission
mechanisms including first, second and third differential gear sets, a
battery, two electric machines serving interchangeably as motors or
generators and four selectable torque-transfer devices. The selectable
torque transmitting devices are engaged to yield an EVT with a
continuously variable range of speeds (including reverse) and four
mechanically fixed forward speed ratios. The torque transmitting devices
and the first and second motor/generators are operable to provide five
operating modes in the electrically variable transmission, including
battery reverse mode, EVT reverse mode, reverse and forward launch modes,
continuously variable transmission range mode, and fixed ratio mode.