摘要 |
<p>A power transmission system of a hybrid electric vehicle may include an input and output shaft. A first planetary gear set disposed on the input shaft includes a first rotation element connected to a first motor/generator, a second rotation element operated as an output element, and a third rotation element connected to the input shaft. A second planetary gear set includes a fourth rotation element connected to a second motor/generator, a fifth rotation element connected to the second rotation element and the output shaft, and a sixth rotation element connected to the first rotation element. A direct-coupling device connects two rotation elements of the second planetary gear set, and transfer gears connect two rotation elements of the first planetary gear set with the two rotation elements of the second planetary gear set. Friction elements connect a selected rotation element to a transfer gear or to the transmission housing.</p> |