SPEED CONTROL FOR A FIXED PTICH RAM AIR TURBINE

• US 20130253734A1
• Filed: 03/23/2012
• Published: 09/26/2013
• Est. Priority Date: 03/23/2012
• Status: Active Grant

• Current Assignee: Hamilton Sundstrand Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Original Assignee: Hamilton Sundstrand Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Kaap, Dustin L., Riordan, Conor
• Granted Patent: US 8,965,659 B2
• Time in Patent Office: Days
• US Class Current: 701/3
• CPC Class Codes: B64D 41/007 Ram air turbines

Abstract

A system of speed control for a ram air turbine of an aircraft includes a power electronics controller, at least one routing device in communication with the power electronics controller, at least one secondary load in serial communication with the at least one routing device and the power electronics controller, and a ram air turbine (RAT) in communication with the power electronics controller, wherein the power electronics controller is configured to apply the secondary load to the RAT through the at least one routing device in response to a transient speed increase of the RAT.

Claims

1. A system of speed control for a ram air turbine of an aircraft, comprising:

a power electronics controller;

at least one routing device in communication with the power electronics controller;

at least one secondary load in serial communication with the at least one routing device and the power electronics controller; and

a ram air turbine (RAT) in communication with the power electronics controller;

wherein the power electronics controller is configured to apply the secondary load to the RAT through the at least one routing device in response to a transient speed increase of the RAT.

2. The system of claim 1, further comprising:

a second routing device in communication with the power electronics controller; and

an essential aircraft load in serial communication with the second routing device and the power electronics controller;

wherein the power electronics controller is further configured to route power to the essential aircraft load through the second routing device in response to aircraft power failure.

3. The system of claim 2, wherein the power electronics controller is further configured to apply the secondary load to the RAT through the at least one routing device in response to a short duration transient load drop of the essential aircraft load.

4. The system of claim 1, wherein the secondary load is an aircraft wing de-icing load.

5. The system of claim 1, further comprising:

a plurality of additional routing devices in communication with the power electronics controller; and

a plurality of additional loads in serial communication with individual routing devices of the plurality of additional routing devices and the power electronics controller;

wherein the power electronics controller is further configured to apply one or more of the plurality of additional loads to the RAT through one or more of the plurality of additional routing devices in response to a transient speed increase of the RAT.

6. The system of claim 1, further comprising:

a plurality of additional routing devices in communication with the power electronics controller; and

a plurality of power sources in serial communication with individual routing devices of the plurality of additional routing devices and the power electronics controller;

wherein the power electronics controller is further configured to apply one or more of the plurality of power sources to the RAT through one or more of the plurality of additional routing devices in response to a transient speed increase of the RAT.

7. The system of claim 6, wherein the plurality of power sources includes at least one battery or super-capacitor.

8. The system of claim 1, wherein the RAT is an inboard RAT.

9. The system of claim 8, further comprising a RAT door mechanism in communication with the power electronics controller and configured to control an amount of air flow to the inboard RAT.

10. The system of claim 9, wherein the power electronics controller is further configured to adjust the RAT door mechanism responsive to changes in speed of the inboard RAT.

11. A method of speed control of a ram air turbine of an aircraft, comprising:

monitoring speed of the ram air turbine (RAT);

determining if the monitored speed meets or exceeds a speed threshold; and

applying a braking load or a braking torque to the ram air turbine responsive to determining the monitored speed meets or exceeds the speed threshold.

12. The method of claim 11, further comprising:

determining if the monitored speed is within a desired speed range; and

adjusting a RAT door aperture responsive to determining the monitored speed is not within the desired speed range.

13. The method of claim 12, wherein adjusting the RAT door aperture comprises:

directing a RAT door mechanism to vary the RAT door aperture responsive to the monitored speed.

14. The method of claim 13, wherein adjusting the RAT door aperture further comprises:

directing the RAT door mechanism to increase the RAT door aperture responsive to determining the monitored speed is below the desired speed range; and

directing the RAT door mechanism to decrease the RAT door aperture responsive to determining the monitored speed is above the desired speed range.

15. The method of claim 11, wherein monitoring the speed of the RAT comprises:

measuring a frequency of power generated at a generator of the RAT; and

calculating a current speed of the RAT based on the measured frequency.

16. The method of claim 11, wherein applying the braking load comprises:

closing a routing device in serial communication with a load and the RAT.

17. The method of claim 11, wherein applying the braking torque comprises:

closing a routing device in serial communication with a power source and the RAT.