Power cable cooling system in a gas turbine engine

1. A cooling system for a gas turbine engine, the cooling system comprising:

an electric machine;

a first conduit including a cable housing and an inlet;

a plurality of conductive cables extending from a point proximal to the electric machine, the plurality of conductive cables disposed at least partially in the cable housing;

an electric fan disposed in the first conduit between the inlet and the electric machine, the electric fan configured to actively cool the plurality of conductive cables by flowing air through the first conduit, the inlet of the first conduit disposed aft of a fan of the gas turbine engine and on an inner surface of an outer wall of a bypass duct; and

a bypass air flow path of the gas turbine engine, the bypass air flow path in fluid communication with an internal cavity of the first conduit, wherein:

the electric fan is configured to actively cool the plurality of conductive cables after an engine shutdown of the gas turbine engine, and

the cooling system is configured to passively flow air through the inlet to cool the plurality of conductive cables during operation of the gas turbine engine.

2. The cooling system of claim 1 , further comprising a second conduit in fluid communication with the first conduit, the second conduit configured to direct an exhaust cooling flow forward of the electric machine.

3. The cooling system of claim 2 , further comprising a tail cone defining a tail cone cavity, the electric machine disposed in the tail cone.

4. The cooling system of claim 3 , wherein the second conduit extends from the tail cone to a drain mast of the gas turbine engine, the drain mast including a plurality of drainage tubes.

5. The cooling system of claim 1 , further comprising a temperature sensor, wherein the electric fan is configured to at least one of activate or increase a rotational speed in response to a measured temperature from the temperature sensor exceeding a predetermined temperature threshold.

6. The cooling system of claim 1 , further comprising a tail cone ejector assembly, the tail cone ejector assembly configured to entrain an exhaust cooling flow through an outlet of a tail cone.

7. A cable cooling system of a gas turbine engine, the cable cooling system comprising:

a control system;

a first sensor configured to communicate with the control system;

an electric fan configured to communicate with the control system; and

a non-transitory computer readable storage medium in electronic communication with the control system, the non-transitory computer readable storage medium having instructions stored thereon that, in response to execution by the control system cause the control system to perform operations comprising:

detecting, by the control system, a shutdown of the gas turbine engine;

activating, by the control system, the electric fan to actively flow air through a conduit having a plurality of conductive cables disposed therein, the conduit defining an inlet in an inner surface of an outer wall of a bypass duct; and

in response to the activating the electric fan, pulling an airflow from a bypass airflow path through the inlet of the conduit, wherein the inlet is configured to receive passive airflow during operation of the gas turbine engine.

8. The cable cooling system of claim 7 , wherein:

the first sensor comprises a temperature sensor disposed in a cable housing, and

the plurality of conductive cables are housed in the cable housing.

9. The cable cooling system of claim 8 , wherein the operations further comprise activating, by the control system, the electric fan in response to a measured temperature from the temperature sensor exceeding a predetermined threshold.

10. The cable cooling system of claim 8 , further comprising a second sensor, wherein the operations further comprise determining, by the control system, an engine shutdown of the gas turbine engine in response to a measurement from the second sensor.

11. The cable cooling system of claim 10 , wherein the second sensor is a weight-on-wheels sensor.

12. The cable cooling system of claim 7 , wherein the operations further comprise determining, by the control system, an engine shutdown of the gas turbine engine in response to a measurement from the first sensor.

13. The cable cooling system of claim 12 , wherein the first sensor comprises a weight-on-wheels sensor.

14. A method of cooling a plurality of conductive cables in electrical communication with an electric machine in a tail cone of a gas turbine engine, the method comprising:

passively cooling, via a cable cooling system and through a conduit of the cable cooling system, the plurality of conductive cables during operation of the gas turbine engine via a bypass airflow received from an inlet of the conduit, the inlet disposed in an inner surface of an outer wall of a bypass duct; and

actively cooling, via the cable cooling system and by an electric fan disposed in the conduit, the plurality of conductive cables by pulling an airflow from a bypass airflow path through the inlet of the conduit in response to at least one of a temperature in a cable housing exceeding a predetermined threshold, an engine shutdown of the gas turbine engine, or a landing event of an aircraft, the electric fan disposed in the conduit.

15. The method of claim 14 , further comprising exhausting a cooling airflow from the cable cooling system forward of the electric machine.

16. The method of claim 14 , further comprising exhausting a cooling airflow from the cable cooling system through a tail cone ejector assembly.

17. The method of claim 14 , wherein actively cooling the plurality of conductive cables further comprises activating the electric fan in response to the engine shutdown of the gas turbine engine.

18. The method of claim 14 , further comprising detecting, via the cable cooling system, at least one of the engine shutdown of the gas turbine engine or the landing event of the aircraft.