Hybrid-electric propulsion system equipped with a coupler for switching between modes of operation

Patent metadata

Field	Value
Publication number	US-12510020-B2
Application number	US-202318351745-A
Country	US
Kind code	B2
Filing date	Jul 13, 2023
Priority date	Jul 19, 2022
Publication date	Dec 30, 2025
Grant date	Dec 30, 2025

Abstract

A propulsion assembly includes a first torque source coupled with a first shaft and a second torque source coupled with a second shaft. A coupler selectively couples the first and second torque sources. When the first and second torque sources are coupled via the coupler, in response to a command to decouple the first torque source, an unloading operation is performed to decrease the torque output provided by the first torque source to a threshold, and when reached, the first shaft is decoupled from the coupler. When the first torque source is coupled with the coupler but the second torque source is not, in response to a command to couple the second torque source, a speed matching operation is performed to increase the speed of the second shaft to match a speed of the first shaft, and when the speeds are matched, the second shaft is coupled to the coupler.

First claim

We claim:

1 . A method, comprising:
providing, by an electric machine, a motor torque output on a coupler mechanically coupled with a propulsor shaft to drive a propulsor; performing, in response to a power turbine couple command, a speed matching operation, wherein performing the speed matching operation comprises increasing a rotational speed of a power turbine shaft mechanically coupled with a power turbine until the rotational speed of the power turbine shaft matches or is within a predetermined range of a rotational speed of an electric machine shaft that mechanically couples the electric machine to the coupler, wherein the coupler includes a transmission shaft that at least partially mechanically couples the electric machine shaft and the power turbine shaft with the propulsor shaft; and when the rotational speed of the power turbine shaft matches or is within the predetermined range of the rotational speed of the electric machine shaft, mechanically coupling the power turbine to the coupler so that the power turbine drives the propulsor, wherein mechanically coupling the power turbine to the coupler comprises modulating one or more actuators to move a coupler turbine shaft that is connected to the transmission shaft so that torque transmitting features of the coupler turbine shaft engage torque transmitting features of the power turbine shaft.

2 . The method of claim 1 , wherein after the power turbine is mechanically coupled to the coupler, a torque output provided by the power turbine on the coupler is held constant for a predetermined time.

3 . The method of claim 1 , wherein after the power turbine is mechanically coupled to the coupler, the method further comprises:
decreasing the motor torque output provided by the electric machine on the coupler to decrease mechanical power transmission from the electric machine to the propulsor; and increasing a torque output provided by the power turbine on the coupler to increase mechanical power transmission from the power turbine to the propulsor.

4 . The method of claim 3 , wherein the motor torque output provided by the electric machine on the coupler is decreased linearly.

5 . The method of claim 3 , wherein the torque output provided by the power turbine on the coupler is increased linearly.

6 . The method of claim 3 , wherein the motor torque output provided by the electric machine on the coupler is decreased linearly and the torque output provided by the power turbine on the coupler is increased linearly.

7 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased and a torque output provided by the power turbine on the coupler is increased so that a net torque provided by the electric machine and the power turbine on the coupler is maintained within a predetermined margin of a commanded torque.

8 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased and a torque output provided by the power turbine on the coupler is increased so that a net torque provided by the electric machine and the power turbine on the coupler is maintained at a constant torque over a turbine loading period.

9 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased at a rate and a torque output provided by the power turbine on the coupler is increased at the rate.

10 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased so that the electric machine switches from a motoring mode to a generating mode to generate electrical power.

11 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased so that the electric machine provides a generator torque output on the coupler.

12 . The method of claim 1 , wherein the motor torque output provided by the electric machine on the coupler is decreased so that the electric machine ceases providing the motor torque output on the coupler, and when the electric machine ceases providing the motor torque output on the coupler, the method further comprises:
mechanically decoupling the electric machine from the coupler.

13 . The method of claim 12 , wherein mechanically decoupling the electric machine from the coupler comprises modulating one of the one or more actuators to move a coupler electric machine shaft of the coupler so that torque transmitting features of the coupler electric machine shaft disengage from torque transmitting features of the electric machine shaft.

14 . The method of claim 1 , further comprising:
monitoring whether the rotational speed of the power turbine shaft matches or is within the predetermined range of the rotational speed of the electric machine shaft based at least in part on one or more inputs received from a resolver associated with the electric machine shaft and one or more inputs received from a resolver associated with the power turbine shaft.

15 . A controller, comprising:
one or more memory devices; one or more processors configured to:
cause an electric machine to provide a motor torque output on a coupler mechanically coupled with a propulsor shaft to drive a propulsor;
in response to a power turbine couple command, cause a speed matching operation to be performed, wherein performing the speed matching operation comprises increasing a rotational speed of a power turbine shaft mechanically coupled with a power turbine until the rotational speed of the power turbine shaft matches or is within a predetermined range of a rotational speed of an electric machine shaft that mechanically couples the electric machine to the coupler, wherein the coupler includes a transmission shaft that at least partially mechanically couples the electric machine shaft and the power turbine shaft with the propulsor shaft; and
when the rotational speed of the power turbine shaft matches or is within the predetermined range of the rotational speed of the electric machine shaft, cause the power turbine to become mechanically coupled with the coupler so that the power turbine drives the propulsor, wherein causing the power turbine to become mechanically coupled with the coupler comprises modulating one or more actuators to move a coupler turbine shaft that is connected to the transmission shaft so that torque transmitting features of the coupler turbine shaft engage torque transmitting features of the power turbine shaft.

16 . A propulsion assembly, comprising:
a gas turbine engine that includes a power spool having a power turbine and a power turbine shaft mechanically coupled with the power turbine; a propulsor assembly that includes a propulsor shaft mechanically coupled with a propulsor; an electric machine; a coupler; and the controller of claim 15 .

17 . A non-transitory computer readable medium comprising computer-executable instructions, which, when executed by one or more processors of a computing system of an aircraft, cause the one or more processors to:
cause an electric machine to provide a motor torque output on a coupler mechanically coupled with a propulsor shaft to drive a propulsor; in response to a power turbine couple command, cause a speed matching operation to be performed, wherein performing the speed matching operation comprises increasing a rotational speed of a power turbine shaft mechanically coupled with a power turbine until the rotational speed of the power turbine shaft matches or is within a predetermined range of a rota

Assignees

• Gen Electric

Inventors

• Zatorski Darek Tomasz
• Murrow Kurt David
• Gemin Paul Robert
• Cioffi Philip M
• Yagielski John Russell

Classifications

• F02K5/00 Primary

  Plants including an engine, other than a gas turbine, driving a compressor or a ducted fan · CPC title

• F02C3/107

  with two or more rotors connected by power transmission · CPC title

• B64D31/00

  Power plant control systems; Arrangement of power plant control systems in aircraft · CPC title

• B64D27/02 Primary

  Aircraft characterised by the type or position of power plants · CPC title

• B64D27/31

  within, or attached to, wings · CPC title