TWO-PLANETARY ELECTRICALLY VARIABLE TRANSMISSIONS WITH MULTIPLE FIXED RATIOS

摘要

The electrically variable transmission family provides low-content, low-cost electrically variable transmission mechanisms including first and second differential gear sets (20, 30), a battery (86), two electric machines (80, 82) serving interchangeably as motors or generators, up to six selectable torque-transfer devices (50, 52, 54, 55, 57, 58) and possibly a dog clutch (392). The selectable torque transmitting devices (50, 52, 54, 55, 57, 58) are engaged to yield an EVT with a continuously variable range of speeds (including reverse) and at least four mechanically fixed forward speed ratios. The torque transmitting devices (50, 52, 54, 55, 57, 58) and the first and second motor/generators (80, 82) 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.