The electrically variable transmission family 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, up to six selectable
torque-transfer devices, and possibly a dog clutch. The selectable torque
transfer devices are engaged to yield an EVT with a continuously variable
range of speeds (including reverse) and mechanically fixed forward speed
ratios. The torque transfer 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.