Electro-mechanical double-rotor compound hybrid transmission
A hybrid vehicle transmission including a double-rotor electric machine, two planetary gear sets, an input shaft, and an output shaft, where the input shaft, the output shaft, and a first rotor of the double-rotor electric machine are each coupled to a member of the first planetary gear set, the output shaft and a second rotor of the double-rotor electric machine are each coupled to a member of the second planetary gear set, and a member of the second planetary gear set not coupled to the output shaft or the second rotor is selectively coupled to the first rotor via a first torque transfer device, and selectively coupled to a transmission housing via a second torque transfer device.
1. A hybrid vehicle transmission comprising:
a first planetary gear set having a first sun gear, a first ring gear, a plurality of first planet gears, and a first planetary carrier;
an input shaft coupled to the first ring gear to transfer power between an engine and the first ring gear;
a second planetary gear set having a second sun gear, a second ring gear, a plurality of second planet gears, and a second planetary carrier;
an output shaft coupled to the first and second planetary carriers to transfer power between the first and second planetary carriers and the output shaft; and
a double-rotor electric machine having a stator, a first rotor, and a second rotor;
the second rotor being coupled to the second sun gear;
the first rotor being coupled to the first sun gear and selectively coupled to the second ring gear via a first torque transfer device; and
the second ring gear being selectively coupled to a transmission housing via, a second torque transfer device.
2. The hybrid vehicle transmission of claim 1 , wherein the double-rotor electric machine is disposed between the first and second planetary gear sets.
3. The hybrid vehicle transmission of claim 1 , wherein the double-rotor electric machine is disposed between the engine and the first planetary gear set.
4. The hybrid vehicle transmission of claim 1 , wherein the second rotor is nested within the first rotor.
5. The hybrid vehicle transmission of claim 4 , wherein the first rotor is nested within the stator.
6. The hybrid vehicle transmission of claim 4 , wherein the stator is nested between the first rotor and the second rotor.
7. The hybrid vehicle transmission of claim 1 , wherein the first rotor comprises offset first and second split rotors, and wherein the first split rotor and the stator operate as a first electric machine, and the second split rotor and the second rotor operate as a second electric machine.
8. The hybrid vehicle transmission of claim 7 , wherein the first split rotor is nested within the stator, and the second rotor is nested within the second split rotor.
9. The hybrid vehicle transmission of claim 1 , wherein the stator comprises offset first and second stators, wherein the first rotor is nested within the first stator, and the second rotor is nested within the second stator, and wherein the second torque transfer device is offset in the same direction from both the first and second stators.
10. The hybrid vehicle transmission of claim 1 , wherein at least one of the first and second torque transfer devices comprises a mechanical clutch.
11. The hybrid vehicle transmission of claim 1 , wherein at least one of the first and second torque transfer devices comprises an electro-mechanically actuated clutch.
12. The hybrid vehicle transmission of claim 1 , wherein the engine comprises an internal combustion engine.
13. The hybrid vehicle transmission of claim 1 , wherein the stator and the first rotor operate as a first electric machine, the first rotor and the second rotor operate as a second electric machine, the first and second electric machines are each connected to an energy storage device, and the first and second electric machines are each selectively operable as either an electric motor or as an electric generator.
14. The hybrid vehicle transmission of claim 13 , wherein:
in a first mode of operation,
the first torque transfer device is actuated to decouple the first rotor and the second ring gear,
the second ring gear is prevented from rotating relative to the transmission housing,
whereby power may be transferred:
between the engine and the output shaft via the first ring gear and the first planetary carrier;
between the engine and the energy storage device via the first electric machine;
between the first electric machine and the output shaft via the first sun gear and the first planetary carrier; and
between the second electric machine and the output shaft via the second sun gear and the second planetary carrier; and
in a second mode of operation,
the first torque transfer device is actuated to couple the first rotor and the second ring gear, and
the second ring gear is prevented from rotating relative to the transmission housing,
whereby power may be transferred:
between the engine and the output shaft via the first ring gear and the first planetary carrier;
between the engine and the output shaft via the first ring gear, the first sun gear, the first rotor, the second ring gear, and the second planetary carrier;
between the first electric machine and the output shaft via the first sun gear and the first planetary carrier;
between the first electric machine and the output shaft via the second ring gear and the second planetary carrier; and
between the second electric machine and the output shaft via the second sun gear and the second planetary carrier.
15. The hybrid vehicle transmission of claim 14 , wherein;
in a third mode of operation,
the first torque transfer device is actuated to decouple the first rotor and the second ring gear,
the second ring gear is prevented from rotating relative to the transmission housing, and
the first rotor and the second rotor are synchronized to rotate at the same rotational speed,
whereby power may be transferred:
between the engine and the output shaft via the first ring gear and the first planetary carrier;
between the engine and the output shaft via the first ring gear, the first sun gear, the first and second rotor, the second sun gear, and the second planetary carrier;
between the first electric machine and the output shaft via the first sun gear and the first planetary carrier; and
between the first electric machine and the output shaft via the second rotor, the second sun gear, and the second planetary carrier; and
in a fourth mode of operation,
the first rotor is prevented from rotating relative to the stator, and
the second ring gear is prevented from rotating relative to the transmission housing,
whereby power may be transferred:
between the engine and the output shaft via the first ring gear and the first planetary carrier; and
between the second electric machine and the output shaft via the second sun gear and the second planetary carrier; and
in a fifth mode of operation,
the first torque transfer device is actuated to couple the first rotor and the second ring gear, and
the first rotor and the second rotor are synchronized to rotate at the same rotational speed,
whereby the rotational speeds of the input shaft and the output shaft are synchronized, and
in a sixth mode of operation,
the first torque transfer device is actuated to couple the first rotor and the second ring gear, and
the second rotor is prevented from rotating relative to the stator,
whereby the rotational speed of the output shaft is greater than the rotational speed of the input shaft, and
in a seventh mode of operation,
the first and second rotors are prevented from rotating relative to the stator,
whereby power may be transferred:
between the engine and the output shaft via the first ring gear and the first planetary carrier.
16. The hybrid vehicle transmission of claim 14 , wherein the first rotor is prevented from rotating relative to the stator by selectively mechanically coupling the first rotor and at least one of the stator and the transmission housing.
17. The hybrid vehicle transmission of claim 14 , wherein the second rotor is prevented from rotating relative to the stator by selectively mechanically coupling the second rotor and at least one of the stator and the transmission housing.
18. The hybrid vehicle transmission of claim 15 , wherein the first rotor and the second rotor are synchronized to rotate at the same rotational speed by selectively mechanically coupling the first rotor and the second rotor.
19. The hybrid vehicle transmission of claim 15 , wherein the first and second rotors are prevented from rotating relative to the stator by:
selectively mechanically coupling the first rotor and at least one of the stator, the second rotor, and the transmission housing; and
selectively mechanically coupling the second rotor and at least one of the stator, the first rotor, and the transmission housing.
20. The hybrid vehicle transmission of claim 15 , wherein in the fourth mode of operation:
the first torque transfer device is actuated to couple the first rotor and the second ring gear, and the second torque transfer device is actuated to couple the second ring gear and the transmission housing;
the first rotor is rotationally locked, and the second torque transfer device is actuated to couple the second ring gear and the transmission housing; or
the first rotor is rotationally locked, and the first torque transfer device is actuated to couple the first rotor and the second ring gear.
21. A hybrid vehicle transmission comprising:
a first planetary gear set having a first sun gear, a first ring gear, and a first planetary carrier;
an input shaft coupled to one of the first sun gear, the first ring gear, and the first planetary carrier;
an output shaft coupled to another one of the first sun gear, the first ring gear, and the first planetary carrier;
a double-rotor electric machine having a stator, a first rotor, and a second rotor,
the first rotor coupled to the one of the first sun gear, the first ring gear, and the first planetary carrier not coupled to the input shaft or the output shaft; and
a second planetary gear set having a second sun gear, a second ring gear, and a second planetary carrier;
one of the second sun gear, the second ring gear, and the second planetary carrier being coupled to the output shaft;
another one of the second sun gear, the second ring gear, and the second planetary carrier being coupled to the second rotor; and
the one of the second sun gear, the second ring gear, and the second planetary carrier not coupled to the output shaft or the second rotor being selectively coupled to the first rotor via a first torque transfer device, and selectively coupled to a transmission housing via a second torque transfer device.
22. The hybrid vehicle transmission of claim 21 , wherein the input shaft is coupled to the first sun gear.
23. The hybrid vehicle transmission of claim 21 , wherein the output shaft is coupled to the first sun gear.