Dual-motor power system and dual-motor hybrid power system for vehicle

A dual-motor hybrid power system for a vehicle, the dual-motor hybrid power system comprising:

• a first motor including a first driving shaft;
• a second motor including a second driving shaft disposed to be coaxial with the first driving shaft;
• an engine disposed to be coupled with the second driving shaft via a clutch;
• an intermediate shaft disposed to be parallel with the first driving shaft and the second driving shaft;
• a first gear set disposed between the first driving shaft and the intermediate shaft and having a first speed-reducing ratio, wherein the first gear set couples the first driving shaft with the intermediate shaft;
• a second gear set having a second speed-reducing ratio;
• a differential driven by the intermediate shaft;
• and
• a synchronizer disposed around the second driving shaft between the first motor and the second motor,
• wherein the synchronizer is configured to be switched between a neutral position, a first-speed-ratio position, and a second-speed-ratio position,
• wherein in the neutral position, the second driving shaft is decoupled from the first gear set and the second gear set,
• wherein in the first-speed-ratio position, the synchronizer couples the second driving shaft with the intermediate shaft via the first gear set, and
• wherein, in the second-speed-ratio position, the synchronizer couples the second driving shaft with the intermediate shaft via the second gear set,
• wherein the first motor is configured as a main motor to continually provide driving power to the vehicle as the vehicle is driven, and
• wherein the second motor is configured as an assistant motor to provide additional driving power to the vehicle as the vehicle is driven.

A transmission for use in a dual-motor power system, the transmission comprising:

• a first driving shaft configured to be turned by a first motor;
• a second driving shaft configured to be turned by a second motor and disposed to be coaxial with the first driving shaft;
• an intermediate shaft disposed to be parallel with the first driving shaft and the second driving shaft;
• a first gear set disposed between the first driving shaft and the intermediate shaft and having a first speed-reducing ratio, wherein the first gear set couples the first driving shaft with the intermediate shaft;
• a second gear set having a second speed-reducing ratio;
• a differential driven by the intermediate shaft;
• and
• a synchronizer disposed around the second driving shaft between the first motor and the second motor,
• wherein the synchronizer is configured to be switched between a neutral position, a first-speed-ratio position, and a second-speed-ratio position,
• wherein in the neutral position, the second driving shaft is decoupled from the first gear set and the second gear set,
• wherein in the first-speed-ratio position, the synchronizer couples the second driving shaft with the intermediate shaft via the first gear set,
• wherein, in the second-speed-ratio position, the synchronizer couples the second driving shaft with the intermediate shaft via the second gear set,
• wherein the first motor is configured as a main motor to continually provide driving power to the vehicle as the vehicle is driven, and
• wherein the second motor is configured as an assistant motor to provide additional driving power to the vehicle as the vehicle is driven.