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US 12,428,997 B2Granted
Multi-mode starter control for gas turbine engines
AssigneeRtx Corporation
InventorsAndre M. Ajami, Donny Davis
Life of this patent
Estimating the term…
Abstract
A starter assembly for a gas turbine engine may include, among other things, at least one electric motor coupled to a respective spool. A controller may be operable to modulate the at least one electric motor in a plurality of control modes. The control modes may include a torque control mode, an acceleration control mode and/or a speed control mode. A method for starting a gas turbine engine is also disclosed.
Claims17
A starter assembly for a gas turbine engine comprising:
- at least one electric motor coupled to a respective spool;
- and
- a controller programmed to modulate the at least one electric motor in a plurality of control modes, the control modes comprising:
- a torque control mode in which the controller is operable to set a torque output of the at least one electric motor to oppose an increase in speed of the respective spool;
- and
- an acceleration control mode in which the controller is operable to cause the at least one electric motor to substantially maintain acceleration of the respective spool at a preselected acceleration rate such that the respective spool substantially achieves a target speed threshold within a preselected duration;
- wherein the controller is programmed to cause the at least one electric motor to operate in the torque control mode subsequent to occurrence of an engine light-off condition until at least one predetermined criterion is met.
4 more elements
A gas turbine engine assembly comprising:
- at least one spool including a turbine coupled to a compressor or a propulsor;
- a combustor;
- and
- a starter assembly including at least one electric motor operable to drive the respective spool during an engine startup condition and including a controller programmed to modulate the at least one electric motor in a plurality of control modes, the control modes comprising:
- an acceleration control mode in which the at least one electric motor substantially maintains acceleration of the respective spool at a preselected acceleration rate until a first predetermined criterion is met;
- a speed control mode in which the at least one electric motor substantially maintains a speed of the respective spool at a preselected holding speed;
- and
- a torque control mode in which the at least one electric motor opposes a change in speed of the respective spool until a second predetermined criterion is met, wherein the second predetermined criterion includes a minimum temperature threshold of the combustor associated with an engine idle condition.
5 more elements
A method for starting a gas turbine engine, the gas turbine engine comprising:
- a starter assembly comprising:
- at least one electric motor coupled to a respective spool of the gas turbine engine;
- and
- a controller programmed to modulate the at least one electric motor in a plurality of control modes, the control modes comprising:
- a torque control mode in which the controller is operable to set a torque output of the at least one electric motor to oppose an increase in speed of the respective spool;
- and
- an acceleration control mode in which the controller is operable to cause the at least one electric motor to substantially maintain acceleration of the respective spool at a preselected acceleration rate such that the respective spool substantially achieves a target speed threshold within a preselected duration;
- wherein the controller is programmed to cause the at least one electric motor to operate in the torque control mode subsequent to occurrence of an engine light-off condition until at least one predetermined criterion is met;
- the method comprising:
- operating the starter assembly in the acceleration control mode, including driving the respective spool with a respective electric motor of the at least one electric motor such that rotation of the respective spool reaches and then is substantially maintained at the preselected acceleration rate to substantially achieve the target speed threshold within the preselected duration;
- and
- operating the starter assembly in the torque control mode, subsequent to occurrence of the engine light-off condition, in which the respective electric motor opposes a change in rotational speed of the respective spool until a preselected engine operating threshold is met.
9 more elements
Dependencies are inferred from the claim text.