HYBRID-ELECTRIC PROPULSION SYSTEM FOR AN AIRCRAFT

• US 20190002115A1
• Filed: 05/17/2017
• Published: 01/03/2019
• Est. Priority Date: 05/17/2017
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Miller, Brandon Wayne, Gansler, Michael Thomas, Adibhatla, Sridhar, Bergsten, Daniel E., Wagner, Nicholas Adam, Gutz, David Allen
• Granted Patent: US 10,633,104 B2
• Time in Patent Office: Days
• 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 27/16 of jet type
• CPC Class Codes: B64D 27/24 using steam or spring force jet aircraft B64D27/16
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: B64D 35/08 characterised by the transmission being driven by a plurality of power plants
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A method of operating a hybrid-electric propulsion system for an aircraft includes determining a flight phase parameter for the aircraft is equal to a first value, and operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value. The method also includes determining the flight phase parameter for the aircraft is equal to a second value different from the first value, and operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value.

Claims

1. A method of operating a hybrid-electric propulsion system for an aircraft, the method comprising:

determining a flight phase parameter for the aircraft is equal to a first value;

operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value, wherein operating the hybrid-electric propulsion system in the electric charge mode comprises driving the electric machine with a combustion engine to generate electrical power, driving a prime propulsor with the combustion engine to generate thrust, and charging an energy storage unit with at least a portion of the electrical power generated;

determining the flight phase parameter for the aircraft is equal to a second value different from the first value; and

operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value, wherein operating the hybrid-electric propulsion system in the electric discharge mode comprising providing electrical power from the energy storage unit to at least one of an electric propulsor assembly to drive the electric propulsor assembly or to the electric machine to drive one or more components of the combustion engine.

2. The method of claim 1, wherein operating the hybrid-electric propulsion system in the electric discharge mode comprises providing electrical power from the energy storage unit to an electric motor of the electric propulsor assembly, the electric motor drivingly connected to a propulsor of the electric propulsor assembly.

3. The method of claim 1, wherein the first value corresponds to the aircraft being in a takeoff flight phase, and wherein the second value corresponds to the aircraft being in a top of climb flight phase.

4. The method of claim 1, wherein the first value corresponds to the aircraft being in a first cruise flight phase, and wherein the second value corresponds to the aircraft being in a second cruise flight phase.

5. The method of claim 1, wherein the first value corresponds to a cruise flight phase, and wherein the second value corresponds to a descent flight phase.

6. The method of claim 1, further comprising:

determining the flight phase parameter for the aircraft is equal to a third value;

operating the hybrid-electric propulsion system in the electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the third value;

determining the flight phase parameter for the aircraft is equal to a fourth value; and

operating the hybrid-electric propulsion system in the electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the fourth value.

7. The method of claim 6, wherein the first value corresponds to the aircraft being in a takeoff flight phase, wherein the second value corresponds to the aircraft being in a top of climb flight phase, wherein the third value corresponds to the aircraft being in a cruise flight phase, and wherein the fourth value corresponds to the aircraft being in a descent flight phase.

8. The method of claim 1, further comprising:

modifying operation of the combustion engine in response to determining the flight phase parameter for the aircraft is equal to the second value.

9. The method of claim 8, wherein modifying operation of the combustion engine comprises operating the combustion engine in an idle or sub-idle mode.

10. The method of claim 9, wherein the combustion engine is a first combustion engine, wherein the prime propulsor is a first prime propulsor, wherein the electric machine is a first electric machine, and wherein modifying operation of the first combustion engine further comprises operating a second combustion engine of the hybrid-electric propulsion system in a high power mode to mechanically drive a second prime propulsor and further to drive a second electric machine to generate electrical power.

11. The method of claim 1, wherein determining the flight phase parameter for the aircraft is equal to the first value comprises determining the value of the flight phase parameter based on a performance map for the aircraft.

12. The method of claim 1, wherein determining the flight phase parameter for the aircraft is equal to the first value comprises:

determining one or more operational parameters of the aircraft; and

determining a value of the flight phase parameter based at least in part on the determined operational parameter of the aircraft.

13. The method of claim 12, wherein the one or more operational parameters of the aircraft includes one or more of an altitude of the aircraft, a change in altitude of the aircraft, an air speed of the aircraft, a change in airspeed of the aircraft, or a duration of a current flight of the aircraft.

14. The method of claim 1, wherein the energy storage unit comprises one or more batteries.

15. The method of claim 1, wherein the aircraft is a helicopter, wherein the combustion engine is a turboshaft engine, and wherein the prime propulsor is a main rotor assembly.

16. The method of claim 15, wherein operating the hybrid-electric propulsion system in the electric discharge mode comprising providing electrical power from the energy storage unit to the electric machine to increase an effective power output of an output shaft of the turboshaft engine.

17. The method of claim 15, wherein the first value corresponds to the aircraft being in a descent flight phase, wherein the second value corresponds to the aircraft being in an ascent flight phase.

18. The method of claim 15, wherein the turboshaft engine comprises an output shaft and a low pressure shaft mechanically coupled to the output shaft, and wherein operating the hybrid-electric propulsion system in the electric charge mode comprises driving the electric machine with the turboshaft engine to generate electrical power to reduce a rotational speed of the output shaft, the low pressure shaft, or both.

19. A hybrid-electric propulsion system for an aircraft comprising:

an electric machine;

a prime propulsor;

a combustion engine mechanically coupled to the prime propulsor for driving the prime propulsor and further coupled to the electric machine;

an electrical energy storage unit electrically connectable to the electric machine;

an electric propulsor assembly electrically connectable to the electrical energy storage unit, the electric machine, or both; and

a controller comprising memory and one or more processors, the memory storing instructions that when executed by the one or more processors cause the hybrid-electric propulsion system to perform functions, the functions including;

determining a flight phase parameter for the aircraft is equal to a first value;

operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value, wherein operating the hybrid-electric propulsion system in the electric charge mode comprises driving the electric machine with the combustion engine to generate electrical power, driving the prime propulsor with the combustion engine to generate thrust, and charging the energy storage unit with at least a portion of the electrical power generated;

determining the flight phase parameter for the aircraft is equal to a second value different from the first value; and

operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value, wherein operating the hybrid-electric propulsion system in the electric discharge mode comprising providing electrical power from the energy storage unit to the electric propulsor assembly to drive the electric propulsor assembly.

20. A hybrid-electric propulsion system for an aircraft comprising:

an electric machine;

a main rotor assembly;

a turbomachine mechanically coupled to the main rotor assembly for driving the main rotor assembly and further coupled to the electric machine;

an electrical energy storage unit electrically connectable to the electric machine; and

a controller comprising memory and one or more processors, the memory storing instructions that when executed by the one or more processors cause the hybrid-electric propulsion system to perform functions, the functions including;

determining a flight phase parameter for the aircraft is equal to a first value;

operating the hybrid-electric propulsion system in an electric charge mode in response to determining the flight phase parameter for the aircraft is equal to the first value, wherein operating the hybrid-electric propulsion system in the electric charge mode comprises driving the electric machine with the turbomachine to generate electrical power, driving the main rotor assembly with the turbomachine to generate thrust, and charging the energy storage unit with at least a portion of the electrical power generated;

determining the flight phase parameter for the aircraft is equal to a second value different from the first value; and

operating the hybrid-electric propulsion system in an electric discharge mode in response to determining the flight phase parameter for the aircraft is equal to the second value, wherein operating the hybrid-electric propulsion system in the electric discharge mode comprising providing electrical power from the energy storage unit to the electric machine to drive one or more components of the turbomachine.