摘要 |
A power transmission system of a hybrid electric vehicle may include an input shaft to which power from an engine is input, an output shaft, a planetary gear set including a first rotation element being driven by electrical driving force, a second rotation element being externally engaged with the output shaft as an output element, and a third rotation element being driven by rotational power of an engine, a first motor/generator directly connected to the first rotation element of the planetary gear set, a second motor/generator selectively externally engaged with the output shaft, a first transfer gear, a second transfer gear, a variable connecting unit selectively connecting the first transfer gear to the input shaft or the output shaft, and a variable direct coupling unit selectively connecting two rotation elements among the three rotation elements, of the planetary gear set. |