A hybrid drive apparatus with a multi-stage transmission provided in the power transmission path, and a control method therefor

摘要

A hybrid drive apparatus, comprising: a power source (8); a generator (MG1); a power split mechanism (10) branching at least a part of the power from the power source (8) to the generator (MG1) and branching the remaining part to a rotation output shaft (14); and a first transmission mechanism (26) disposed in a power transmission path from the rotation output shaft (14) to the drive wheels (38), the first transmission mechanism (26) capable of operating in accordance with a driver's operation select normal gear stage and at least one low-speed-side gear stage set to a gear ratio larger than that of the normal gear stage; an electric motor (MG2) connected to the power transmission path between the power transmission mechanism (10) and the first transmission mechanism (26) and generating a driving force using electric power; a vehicle speed determination unit (30); and a controller (50) that controls operations of the power source (8), the generator (MG1), and the electric motor (MG2); characterized in that, when in the first gear mechanism (26) the gear stage is selected on the low-speed side, the control unit (50) performs such a control operation that the vehicle speed is set at a low speed.