Engine control system

• US 6,986,641 B1
• Filed: 07/07/2003
• Issued: 01/17/2006
• Est. Priority Date: 09/26/2001
• Status: Expired due to Term

• Current Assignee: Triumph Engine Control Systems LLC (Triumph Group, Inc.)
• Original Assignee: Goodrich Pump & Engine Control Systems, Inc. (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Desai, Mihir C., Mattice, Jeffrey S., Stanecki, Tomasz J.
• Primary Examiner(s): Look, Edward K.
• Assistant Examiner(s): Edgar, Richard A.
• Application Number:
  US10/614,364
• Time in Patent Office: 925 Days
• Field of Search: 415/13, 415/16, 416/31, 416/43, 416/44
• US Class Current: 416/44
• CPC Class Codes: B64C 27/001 Vibration damping devices
• CPC Class Codes: B64C 27/14 Direct drive between power plant and rotor hub
• CPC Class Codes: B64D 31/06 actuated automatically
• CPC Class Codes: F02C 9/28 Regulating systems responsive to plant or ambient parameters, e.g. temperature, pressure, rotor speed F02C9/30 - F02C9/38, F02C9/44 take precedence
• CPC Class Codes: F02C 9/56 with power transmission control
• CPC Class Codes: F05D 2220/329 in helicopters
• CPC Class Codes: F05D 2270/02 to control rotational speed (n)
• CPC Class Codes: F05D 2270/052 Torque
• CPC Class Codes: G05B 5/01 electric

Abstract

A power turbine speed control system for a helicopter is disclosed which includes components for generating a power turbine speed signal based upon a demanded rotor speed, a high-order filter for filtering the power turbine speed signal by effectuating a rapid attenuation of main and tail rotor torsional frequencies in the power turbine speed signal without compromising phase at low frequencies, and a governor for providing isochronous power turbine speed and rotor speed control based upon the filtered power turbine speed signal.

Claims

1. A power turbine speed control system for a helicopter comprising:

a) means for generating a power turbine speed signal based upon a demanded speed;

b) means for filtering the power turbine speed signal by effectuating a rapid attenuation of main and tail rotor torsional frequencies in the power turbine speed signal without compromising phase at low frequencies;

c) a governor for providing isochronous power turbine speed and rotor speed control based upon the filtered power turbine speed signal; and

d) damping means for actively damping main and tail rotor torsional frequencies.

2. A power turbine speed control system as recited in claim 1, wherein the damping ineans includes means for estimating a plurality of engine states based upon a single measured engine state.

3. A power turbine speed control system as recited in claim 2, wherein the single measured engine state is power turbine shaft torque.

4. A power turbine speed control system as recited in claim 1, wherein the damping means includes a linear quadratic regulator that provides combustive damping.

5. A power turbine speed control system as recited in claim 1, further comprising means for selectively activating the damping means.

6. A turbine speed control system as recited in claim 1, wherein the damping means is tuned to provide attenuation of resonant frequencies so as not to influence low frequency response of the system.

7. A power turbine speed control system as recited in claim 6, wherein the damping means includes a high pass filter.