Method to control electric starter generator for gas turbine engines

Patent metadata

Field	Value
Publication number	US-9803553-B2
Application number	US-201514691925-A
Country	US
Kind code	B2
Filing date	Apr 21, 2015
Priority date	Apr 25, 2014
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

A gas turbine engine starting system including an electric start generator (ESG) free of temperature sensors and configured to provide torque to a gas turbine engine. A fuel metering module is configured to provide a quantity of fuel to the gas turbine engine, and an electronic control system (ECS). The ESG includes a plurality of subcomponents. The ECS is configured to predict a future temperature of the ESG, predict that at an ongoing start or an uninitiated start will be unsuccessful, and provide the prediction that at an ongoing start or an uninitiated start will be unsuccessful to an operator. The prediction of the future temperature of the ESG is based on a plurality of historical ESG thermal trending information and an input ambient temperature. The prediction that at an ongoing start or an uninitiated start will be unsuccessful is based on the future temperature of the ESG.

First claim

What is claimed is:

1. A gas turbine engine starting system comprising:
an electric start generator (ESG) free of temperature sensors and configured to provide torque to a gas turbine engine, wherein the ESG comprises a plurality of subcomponents;
a fuel metering module configured to provide a quantity of fuel to the gas turbine engine; and
an electronic control system (ECS) that:
determines a future temperature of the ESG based on a plurality of historical ESG thermal trending information and an input ambient temperature;
determines whether at least one of an ongoing start and an uninitiated start will be unsuccessful, wherein the determination of whether at least one of the ongoing start and the uninitiated start will be unsuccessful is based on the future temperature of the ESG; and
indicates the determination of whether at least one of the ongoing start and the uninitiated start will be unsuccessful to an operator.

2. The gas turbine engine starting system of claim 1 , wherein the ECS further:
causes the fuel metering module to provide the quantity of fuel to the gas turbine engine; and
aborts the ongoing start based on the future temperature of the ESG.

3. The gas turbine engine starting system of claim 1 , wherein the determination of whether at least one of the ongoing start and the uninitiated start will be unsuccessful is further based on a comparison of the future temperature and a first thermal limit of the ESG.

4. The gas turbine engine starting system of claim 1 , wherein the ECS comprises:
a full authority digital engine control (FADEC) unit that:
identifies a proposed ESG amperage change condition, wherein the proposed ESG amperage change condition proposes at least one of an ESG stator amperage be driven at a first different stator amperage and an ESG field amperage be driven at second different field amperage;
determines an ESG temperature based on the proposed ESG amperage change condition, wherein ESG temperature is a predicted temperature of the ESG if driven by the proposed ESG amperage change condition; and
determines whether the ESG temperature exceeds a thermal limit of the ESG.

5. The gas turbine engine starting system of claim 4 , further comprising an ESG control unit that controls the ESG, wherein the ECS further:
determines an ESG torque command based on the proposed ESG amperage change condition; and
sends the ESG torque command to the ESG control unit if the predicted ESG temperature fails to exceed the thermal limit.

6. The gas turbine engine starting system of claim 1 , wherein the determination of whether the future temperature of the ESG is further based on a sensed gas turbine engine oil temperature.

7. The gas turbine engine starting system of claim 6 , wherein the ECS further determines a plurality of ESG subcomponent temperatures based on a plurality of ESG subcomponent heat capacity values.

8. The gas turbine engine starting system of claim 1 , wherein the ECS further:
determines a present temperature of at least one of the ESG and the plurality of subcomponents, wherein the present temperature is based on at least one of a sensed amperage, an sensed speed, a sensed coolant temperature, and a sensed ambient air temperature; and
aborts the ongoing start if the present temperature exceeds a thermal limit.

9. A gas turbine engine starting system comprising:
a systems controller that:
receives a plurality of sensor inputs, wherein the plurality of sensor inputs comprises a sensed engine speed and a sensed ambient air temperature;
determines a future temperature of at least one subcomponent of an electrical start generator (ESG), wherein the prediction of the future temperature is based on the plurality of sensor inputs and a plurality of ESG historical thermal information; and
stores the future temperature on a non-transitory storage medium.

10. The gas turbine engine starting system of claim 9 , further comprising an ESG free of temperature sensors and that outputs a quantity of torque to a gas turbine engine, wherein the ESG comprises the plurality of ESG subcomponents.

11. The gas turbine engine starting system of claim 10 , wherein the plurality of sensor inputs further comprises a sensed engine temperature and a sensed engine coolant temperature, and wherein the determination of the future temperature of each subcomponent of the plurality of ESG subcomponents is further based on the sensed engine temperature and the sensed engine coolant temperature.

12. The gas turbine engine starting system of claim 11 , wherein the systems controller further determines whether a sensed engine system temperature exceeds an engine thermal limit.

13. The gas turbine engine starting system of claim 11 , wherein the systems controller further:
determines a quantity of fuel a fuel metering module will provide to a gas turbine engine;
causes the fuel metering module to provide the quantity of fuel to the gas turbine engine;
determines an quantity of ESG torque the ESG will provide to the gas turbine engine; and
causes the ESG to provide the quantity of ESG torque to the gas turbine engine.

14. The gas turbine engine starting system of claim 11 , wherein the systems controller further:
determines whether an active starting operation will cause the ESG to exceed an ESG thermal limit and cause the gas turbine engine to exceed an engine thermal limit, and
wherein the determination whether the active starting operation will cause the ESG to exceed the ESG thermal limit is based on the future temperature of each subcomponent of the plurality of ESG subcomponents.

15. The gas turbine engine starting system of claim 11 , wherein the systems controller further aborts an ongoing ESG operation based on the future temperature of each subcomponent of the plurality of ESG subcomponents.

16. The gas turbine engine starting system of claim 10 , wherein the systems controller further:
determines a present temperature of at least one subcomponent of the ESG based on at least one of a sensed amperage, a sensed speed, a sensed coolant temperature, and a sensed ambient air temperature;
compares at least one of the present temperature and the future temperature to a thermal limit; and
based on the comparison, identifies at least one of a lifespan of the ESG and an abort condition of an ongoing start condition.

17. The gas turbine engine starting system of claim 9 , wherein the systems controller further:
models a present temperature of the least one subcomponent of the ESG during a start operation;
identifies at least one trend in a plurality of recorded modeled temperatures of the at least one subcomponent of the ESG, wherein the plurality of modeled temperature includes the present temperature; and
determines a health property of the ESG based on the at least one trend.

18. A method of starting a gas turbine engine comprising:
receiving a plurality of sensor information, wherein the plurality sensor information includes sensed engine speed, sensed ambient temperature, and sensed oil temperature;
modifying a first starting condition for an electric starting generator (ESG) based on the plurality of sensor information and a plurality of historical ESG thermal information, wherein the plurality of historical ESG thermal information includes a plurality of historical temperature data of a respective plurality of ESG subcomponents; and
sending the first starting condition to an ESG controller that controls the ESG.

19. The method of claim 18 , further comprising:
determining a first temp

Assignees

• Rolls Royce Nam Tech Inc
• Rolls Royce Corp

Inventors

• Smith Alan W
• Blackwelder Mark J

Classifications

• F05D2260/821

  Parameter estimation or prediction · CPC title

• F05D2230/72

  Maintenance · CPC title

• F01D21/12

  responsive to temperature · CPC title

• F05D2220/32

  in gas turbines · CPC title

• F02K3/06

  with front fan · CPC title