HYBRID DRIVE SYSTEM FOR TRANSFERRING POWER FROM A GAS TURBINE ENGINE OF AN AIRCRAFT

• US 20180266329A1
• Filed: 03/15/2017
• Published: 09/20/2018
• Est. Priority Date: 03/15/2017
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Mackin, Steve
• Granted Patent: US 10,208,675 B2
• Time in Patent Office: Days
• CPC Class Codes: B64D 2013/0618 with arrangements for reducing or managing bleed air, using another air source, e.g. ram air
• CPC Class Codes: B64D 27/026 comprising different types of power plants, e.g. combination of a piston engine and a gas-turbine Hybrid electric aircraft B64D27/33
• CPC Class Codes: B64D 27/10 of gas-turbine type jet aircraft B64D27/16
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: F02C 7/36 Power transmission arrangements between the different shafts of the gas turbine plant, or between the gas-turbine plant and the power user F02C3/107 - F02C3/13 and F02C7/32 take precedence; couplings for transmitting rotation F16D; gearing in general F16H
• CPC Class Codes: F05D 2220/76 an electrical generator
• CPC Class Codes: F05D 2260/40311 of the epicyclical, planetary or differential type
• CPC Class Codes: H02K 16/00 Machines with more than one rotor or stator machines for transmitting mechanical power from a driving shaft to a driven shaft and comprising structurally interrelated motor and generator parts H02K51/00; permanent magnet machines with multiple rotors or stators relatively rotated for vectorially combining the excitation fields or the armature voltages H02K21/029
• CPC Class Codes: H02K 7/116 with gears
• CPC Class Codes: H02K 7/14 Structural association with mechanical loads, e.g. with hand-held machine tools or fans with fan or impeller for cooling the machine H02K9/06
• CPC Class Codes: H02K 7/1823 structurally associated with turbines or similar engines
• CPC Class Codes: Y02T 50/50 On board measures aiming to increase energy efficiency
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A hybrid drive system driven by a gas turbine engine is disclosed. The hybrid drive system includes a planetary gear set, a first motor-generator, and a second motor-generator. The planetary gear set includes a first member, a second member, and a third member. The first member is operatively coupled to the second member and the third member. The first member is operatively coupled to and transmits power from a shaft of the gas turbine engine. The first motor-generator is drivingly coupled to the third member. The second motor-generator includes an output and is drivingly coupled to the second motor-generator by the second member and the third member. The hybrid drive system is configured to transfer the power from the shaft to the output of the second motor-generator.

Claims

1. A hybrid drive system (12) driven by a gas turbine engine (18), the hybrid drive system (12) comprising:

a planetary gear set (36) including a first member (90), a second member (92), and a third member (94), the first member (90) operatively coupled to the second member (92) and the third member (94), and wherein the first member (90) is operatively coupled to and transmits power from a shaft (28) of the gas turbine engine (18);

a first motor-generator (38) drivingly coupled to the third member (94); and

a second motor-generator (40) including an output (42), the first motor-generator (38) drivingly coupled to the second motor-generator (40) by the second member (92) and the third member (94), wherein the hybrid drive system (12) is configured to transfer the power from the shaft (28) to the output (42) of the second motor-generator (40).

2. The hybrid drive system (12) of claim 1, wherein the second motor-generator (40) operates as a generator to transfer additional shaft power to the first motor-generator (38) during a high altitude transition point and a descent of the aircraft (8).

3. The hybrid drive system (12) of claim 1, wherein the first motor-generator (38) operates as a generator to transfer additional shaft power to the second motor-generator (40) during takeoff, climb, or cruise of the aircraft (8).

4. The hybrid drive system (12) of claim 1, comprising a controller (100) in communication with the first motor-generator (38) and the second motor-generator (40), wherein the controller (100) is configured to control a rotational speed and a direction of both the first motor-generator (38) and the second motor-generator (40).

5. The hybrid drive system (12) of claim 1, wherein the first member (90) is a carrier, the second member (92) is a ring gear, and the third member (94) is a sun gear.

6. The hybrid drive system (12) of claim 1, wherein the hybrid drive system (12) is configured to transfer the power from the shaft (28) into substantially constant power and substantially constant speed at the output (42) of the second motor-generator (40) when the gas turbine engine (18) operates at a flight idle during a high altitude transition point and during descent of the aircraft (8).

7. The hybrid drive system (12) of claim 1, wherein the shaft (28) is either a low pressure shaft or an intermediate shaft and the gas turbine engine (18) includes a three-spool configuration.

8. An aircraft (8), comprising:

a gas turbine engine (18) including a shaft (28);

a power takeoff shaft (62) that extracts power from the shaft (28) of the gas turbine engine (18);

a device (50) configured to produce substantially constant power and substantially constant rotational speed when the aircraft (8) operates at a high altitude transition point and during descent of the aircraft (8); and

a hybrid drive system (12), comprising;

a planetary gear set (36) including a carrier (90), a ring gear (92), and a sun gear (94), the carrier (90) operatively coupled to the ring gear (92) and the sun gear (94), and wherein the carrier (90) is operatively coupled to the shaft (28) of the gas turbine engine (18);

a first motor-generator (38) drivingly coupled to the sun gear (94); and

a second motor-generator (40) including an output (42) operatively coupled to the device (50), the first motor-generator (38) drivingly coupled to the second motor-generator (40) by the ring gear (92) and the sun gear (94), wherein the hybrid drive system (12) is configured to transfer the power from the shaft (28) into the substantially constant power and the substantially constant speed at the output (42) of the second motor-generator (40) when the gas turbine engine (18) operates at a flight idle during the high altitude transition point and the descent of the aircraft (8).

9. The aircraft (8) of claim 8, wherein the second motor-generator (40) operates as a generator to transfer additional shaft power to the first motor-generator (38) during the high altitude transition point and the descent of the aircraft (8).

10. The aircraft (8) of claim 8, wherein the first motor-generator (38) operates as a generator to transfer additional shaft power to the second motor-generator (40) during takeoff, climb, or cruise of the aircraft (8).

11. The aircraft (8) of claim 8, comprising a controller (100) in communication with the first motor-generator (38) and the second motor-generator (40), wherein the controller (100) is configured to control a rotational speed and a direction of both the first motor-generator (38) and the second motor-generator (40).

12. The aircraft (8) of claim 8, comprising a gear box (66) that drivingly couples the low pressure shaft (28) to the power takeoff shaft (62).

13. The aircraft (8) of claim 8, wherein the gas turbine engine (18) includes a two-spool configuration and the shaft (28) is a low pressure shaft.

14. The aircraft (8) of claim 8, wherein the gas turbine engine (18) includes a three-spool configuration and the shaft (28) is either a low pressure shaft or an intermediate shaft.

15. The aircraft (8) of claim 8, wherein the device (50) is a cabin air compressor (CAC) (250) having an impeller (256).

16. The aircraft (8) of claim 8, wherein the (CAC) (250) includes either variable inlet guide vanes (270) located upstream of the impeller (256) or a variable diffuser (280) located downstream of the impeller (256).

17. The aircraft (8) of claim 8, wherein the device (50) is either a constant frequency generator or a variable frequency generator.

18. A method for powering a device (50) by a gas turbine engine (18) during a high altitude transition point and during descent of an aircraft (8), the method comprising:

extracting power from a shaft (28) of the gas turbine engine (18) by a power takeoff shaft (62), wherein the power takeoff shaft (62) is drivingly coupled to a carrier (90) of a planetary gear set (36);

driving a first motor-generator by a sun gear (94) of the planetary gear set (36), wherein the carrier (90) is operatively coupled to the sun gear (94);

coupling the first motor-generator (38) to a second motor-generator (40) by a ring gear (92) and the sun gear (94); and

transferring substantially constant power and substantially constant speed from an output (42) of the second motor-generator (40) to a device (50) when the gas turbine engine (18) operates at a flight idle during the high altitude transition point and the descent of the aircraft (8).

19. The method of claim 18, comprising operating the second motor-generator (40) as a generator to transfer additional shaft power to the first motor-generator (38) during the high altitude transition point and the descent of the aircraft (8).

20. The method of claim 18, comprising operating the first motor-generator (38) as a generator to transfer additional shaft power to the second motor-generator (40).