Method for controlling a combustion apparatus and control device

Patent metadata

Field	Value
Publication number	US-11525417-B2
Application number	US-201816638408-A
Country	US
Kind code	B2
Filing date	Aug 21, 2018
Priority date	Sep 1, 2017
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A method for controlling a combustion apparatus having a combustion state in which a parameter related to the combustion state reflects a chaotic behavior is provided. The method includes the steps of measuring the parameter and determining a time series of the parameter, shifting the time series by a variable time delay for determining a time-shifted signal, and forming a difference between the time-shifted signal and the time series for determining a time dependent first signal, so that a norm of the difference is lowest. A time dependent second signal is determined, wherein determining the time dependent second signal includes at least one of using a frequency of a desired oscillating combustion state, and shifting the time series by a set time delay. The first signal and the second signal are combined to determine a control signal. The control signal is used to influence the combustion apparatus.

First claim

The invention claimed is:

1. A method for controlling a combustion apparatus comprising a combustion state in which a parameter (p) related to the combustion state reflects a chaotic behavior, the method comprising:
measuring the parameter (p) and determining a time series (S 0 , p 1 ) of the parameter (p);
shifting the time series (S 0 ) by a variable time delay (τ var ) for determining a time-shifted signal (S τ ), and forming a difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) for determining a time dependent first signal (S 1 ), so that a norm of the difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) is lowest;
determining a time dependent second signal (S 2 ) different to the first signal (S 1 ), wherein determining the time dependent second signal (S 2 ) comprises at least one of using a frequency (f OL ) of a desired periodic combustion state of the combustion apparatus, and shifting the time series (S 0 ) by a set time delay (τ set );
combining the first signal (S 1 ) and the second signal (S 2 ) for determining a control signal (S, p 2 ); and
using the control signal (S, p 2 ) to influence the combustion apparatus.

2. The method of claim 1 , wherein combining the first signal (S 1 ) and the second signal (S 2 ) comprises at least one of determining a function (F) of the first signal (S 1 ) and the second signal (S 2 ), determining a sum of the first signal (S 1 ) and the second signal (S 2 ), and determining a weighted sum of the first signal (S 1 ) and the second signal (S 2 ).

3. The method of claim 1 , wherein the norm corresponds to a sum of absolute amplitude values of the difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ), and/or wherein the norm corresponds to a root mean square value of the amplitude values of the difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ).

4. The method of claim 1 , wherein the parameter is a pressure in the apparatus, a temperature in the apparatus, a density in the apparatus, a radiation power of the combustion or a parameter related to at least one of the pressure, the temperature, the density and the radiation power.

5. The method of claim 1 , further comprising analyzing the time series (S 0 ) to determine a characteristic of a current state of the combustion, changing an input parameter ({a}) of the function (F) and/or changing the set time delay (τ set ).

6. The method of claim 1 , wherein determining the time series (S 0 ) comprises high-pass filtering the measured parameter (p 1 ), and/or wherein determining the time dependent first signal (S 1 ) comprises varying the variable time delay (τ var ).

7. The method of claim 1 , wherein using the control signal (S, p 2 ) comprises at least one of:
saturating the control signal (S) to form a saturated control signal;
feeding the control signal (S) or the saturated control signal to an actuator coupled with the combustion apparatus;
modulating a fuel-oxidant ratio of the combustion apparatus;
modulating a flow rate of the combustion apparatus;
converting the control signal (S) or the saturated control signal into an acoustic signal; and
applying the acoustic signal to the combustion apparatus.

8. The method of claim 1 , wherein the method is performed in a cyclic manner and/or continuously.

9. A control device, comprising:
a sensor for measuring a parameter (p) related to a combustion state of a combustion apparatus;
a controller connected with the sensor and configured to:
receive measured values (p 1 ) of the parameter (p) from the sensor and to determine a time series (S 0 ) of the measured values of the parameter (p);
shift the time series (S 0 ) by a variable time delay ( 96 var ) for determining a time-shifted signal (S τ ), and form a difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) for determining a time dependent first signal (S 1 ), so that a norm of the difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) is lowest;
determine a time dependent second signal (S 2 ) different to the first signal (S 1 ), wherein the second signal (S 2 ) is determined based on a frequency (f OL ) of a desired periodic state of the combustion apparatus and/or wherein determining the second signal (S 2 ) comprises shifting the time series (S 0 ) by a set time delay (τ set ); and
output a function (F) of the first signal (S 1 ) and the second signal (S 2 ) as a primary control signal (S); and

an actuator connected with the controller and configured to convert the primary control signal (S) into a secondary control signal (p 2 ) suitable to influence the combustion apparatus.

10. The device of claim 9 , wherein the sensor is a pressure sensor, a temperature sensor or a light sensor.

11. The device of claim 9 , wherein the actuator is an acoustic actuator, an electromagnetically driven membrane, a valve or a pump.

12. The device of claim 9 , wherein the control device comprises an observer unit configured to determine at least one of:
a characteristic of a current state of the combustion apparatus using the time series (S 0 ) or the measured values (p 1 ) of the parameter (p);
using the characteristic for changing an input parameter ({a}) of the function (F); and
using the characteristic for changing the set time delay (τ set ).

13. The device of claim 9 , wherein control device is configured to:
measure the parameter (p) and determining a time series (S 0 , p 1 ) of the parameter (p);
shift the time series (S 0 ) by a variable time delay (τ var ) for determining a time-shifted signal (S τ ), and forming a difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) for determining a time dependent first signal (S 1 ), so that a norm of the difference (S τ - S 0 ) between the time-shifted signal (S τ ) and the time series (S 0 ) is lowest;
determine a time dependent second signal (S 2 ) different to the first signal (S 1 ), wherein determining the time dependent second signal (S 2 ) comprises at least one of using a frequency (f OL ) of a desired periodic combustion state of the combustion apparatus, and shifting the time series (S 0 ) by a set time delay (τ set );
combine the first signal (S 1 and the second signal (S 2 ) for determining a control signal (S, p 2 ); and
use the control signal S, p 2 ) to influence the combustion apparatus.

14. A controlled system comprising a chamber and the control device claim 9 coupled with the chamber.

15. The system of claim 14 , wherein the chamber is a combustion chamber, and/or wherein the controlled system is formed by or includes at least one of a jet engine, a rocket engine, a gas turbine engine, a furnace, a boiler, or an afterburner.

Assignees

• Univ Berlin Tech

Inventors

• Paschereit Christian Oliver
• Saurabh Aditya
• Kabiraj Lipika

Classifications

• F23N5/203 Primary

  using electronic means · CPC title

• F23N5/242

  using electronic means · CPC title

• F23N2225/08

  temperature · CPC title

• F23N5/02

  using devices responsive to thermal changes or to thermal expansion of a medium · CPC title

• F02D41/1402 Primary

  Adaptive control · CPC title