ELECTRIC DRIVELINE SYSTEM AND ELECTRIC DRIVELINE SYSTEM OPERATING METHOD
Methods and systems for an electric driveline are provided. In one example, the electric driveline system includes a transmission with a planetary gearset, with a first gearset component rotationally coupled to a first electric machine and a second electric machine, and a first output interface and a second output interface rotationally coupled to a first axle and a second axle, respectively, and a second gearset component in the planetary gearset. The driveline system further includes a first friction clutch configured to selectively brake a third gearset component and a second friction clutch configured to selectively couple the first gearset component to an output shaft.
1 . An electric driveline system, comprising:
a planetary gearset with a gear that directly meshes with two gears that are rotationally coupled to a first electric machine and a second electric machine, respectively;
an output shaft including a first output interface and a second output interface and rotationally coupled to the planetary gearset; and
a first clutch configured to selectively rotationally couple the gear to the output shaft.
2 . The electric driveline system of claim 1 , wherein the gear is rotationally coupled to a sun gear in the planetary gearset.
3 . The electric driveline system of claim 1 , further comprising a second clutch configured to selectively ground a ring gear in the planetary gearset.
4 . The electric driveline system of claim 3 , wherein the second clutch is a friction clutch.
5 . The electric driveline system of claim 3 , further comprising a synchronizer selectively rotationally coupled to the ring gear and the second clutch.
6 . The electric driveline system of claim 1 , wherein the first clutch is a friction clutch.
7 . The electric driveline system of claim 1 , wherein the electric driveline system is included in an all-electric vehicle.
8 . The electric driveline system of claim 1 , wherein the planetary gearset is a simple planetary gearset.
9 . The electric driveline system of claim 1 , further comprising a third electric machine mechanically driving a lubricant pump.
10 . A method for operation of an electric driveline system, comprising:
directly transferring rotational energy from two gears which are rotationally coupled to a first electric machine and a second electric machine, respectively, to a gear which is included in a planetary gearset; and
shifting into a first gear configuration via engagement of a first clutch to rotationally couple the gear and an output shaft;
wherein the output shaft includes a first output interface and a second output interface and is rotationally coupled to the planetary gearset.
11 . The method of claim 10 , wherein shifting into the first gear configuration includes disengaging a second clutch.
12 . The method of claim 11 , wherein the second clutch is configured to brake a ring gear in the planetary gearset when engaged.
13 . The method of claim 11 , wherein the first clutch and the second clutch are friction clutches.
14 . The method of claim 11 , further comprising shifting into a second gear configuration via disengagement of the first clutch and engagement of the second clutch.
15 . An electric driveline system, comprising:
a planetary gearset with a gear that is rotationally coupled to a first electric machine and a second electric machine;
an output shaft including a first output interface and a second output interface which are rotationally coupled to a first axle and a second axle, respectively;
a first friction clutch configured to brake a ring gear in the planetary gearset; and
a second friction clutch configured to rotationally couple the gear and the output shaft.
16 . The electric driveline system of claim 15 , further comprising a synchronizer selectively rotationally coupled to the ring gear and the second friction clutch.
17 . The electric driveline system of claim 15 , further comprising a mechanical power take-off (PTO) coupled to the output shaft of the first electric machine or the second electric machine.
18 . The electric driveline system of claim 17 , further comprising a PTO clutch coupled to the output shaft of the first electric machine or the second electric machine.
19 . The electric driveline system of claim 15 , wherein a carrier in the planetary gearset is directly coupled to the output shaft.
20 . The electric driveline system of claim 19 , wherein the planetary gearset is a simple planetary gearset.