Nissan Diesel Motor Co., Ltd.

Yuji Suzuki

Mitsuhiro Nishina

Hideaki Gouda

In a hybrid-drive electric vehicle, upon request of gear shifting of a transmission (), a clutch () is first disconnected and the transmission () is set to a neutral position. The rotating electric generatoris then operated in a motor mode or a power generating mode so that a rotational speed of an input shaft of the transmission () reaches a region of a synchronizing rotational speed in accordance with a requested gear position. When the rotational speed of the input shaft of the transmission () reaches the region of the synchronizing rotational speed, the gear position of the transmission () is changed over from the neutral position to the requested gear position. Thus the rotation synchronizing time for the gear shifting in the transmission () is reduced, making it possible to perform the gear shifting for a short period of time.

Gear shift control system of hybrid vehicle

A controller () of a hybrid vehicle determines an engine torque at a point on an engine torque high efficiency line at the current engine rotation speed as a target engine torque, and determines the current engine torque from the current engine rotation speed and current accelerator depression amount. Then, when the gear position of a transmission () is neutral, the vehicle is stationary and a storage device () requires charging, the controller () sets the difference between the target engine torque and the current engine torque as a target power generation torque of a motor generator (), sets a transitional time period corresponding to the target power generation torque, and performs control over the transitional time period to raise the power generation torque of the motor generator gradually to the target power generation torque.

Hybrid vehicle and method of controlling the vehicle

A hybrid electric drive system for a vehicle comprises a combustion engine (), a transmission (), a first clutch () disposed between the engine () and the transmission (), a rotating electric machine () which serves as a motor as well as a generator, a second clutch () disposed between the rotating electric machine () and the transmission (), and a storage device (). When the second clutch () is commanded to connect the rotating electric machine () to the transmission (), a control unit () controls the rotating electric machine () so as to decrease the difference between the rotation speeds of the rotating electric machine () and the transmission () (S) and cause the second clutch () to connect the rotating electric machine () to the transmission () only after the difference decreases to a allowable value (SS).

Growing community of inventors

Ageo, Japan

Yuji Suzuki