Active control system and method for combustion instability of annular combustion chamber

Abstract

The invention relates to an active control system and method for combustion instability of an annular combustion chamber, and belongs to the technical field of combustion gas turbine combustion control. The system comprises a fuel tank, a fuel pump, the annular combustion chamber, a sensor group, a high-frequency data processing unit and a high-frequency valve group; the sensor group is used for measuring pulsating pressure in the annular combustion chamber and transmitting measured data to the high-frequency data processing unit; the high-frequency data processing unit is used for identifying a combustion instability mode according to the pulsating pressure and generating a corresponding control signal according to the combustion instability mode; and the high-frequency valve group comprises a plurality of high-frequency valves and is used for receiving the control signals and actively controlling the combustors. According to the method, flexible regulation and control are carried out aiming at various unstable combustion modes, accurate control is achieved, pressure pulsation and heat release pulsation of the annular combustion chamber can be effectively reduced, combustion instability of the annular combustion chamber of the gas turbine is restrained, the service life of the gas turbine is prolonged, and operation safety of the gas turbine is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas turbine combustion control, and particularly relates to an active control system and method for combustion instability of an annular combustor. Background Technique

[0002] Combustion instability is a common and difficult-to-solve technical problem in advanced aeroengines and annular combustors of gas turbines, which is caused by the coupled feedback of pressure pulsation and flame heat release rate pulsation in the annular combustor. Combustion instability has many negative impacts on the operation of gas turbines and aeroengines, including narrowing the stable operation range of the engine, reducing the combustion efficiency, increasing pollutant emissions, and even possibly causing structural damage to the annular combustor in severe cases, threatening the system safety. Therefore, the effective control of combustion instability has become a key technical problem to be solved urgently in the fields of gas turbines and aeroengines.

[0003] The control methods of combustion instability are mainly divided into passive control and active control. The passive control method suppresses combustion instability by designing an acoustic absorption structure or adjusting the geometric parameters of the annular combustor, but it is difficult to play a role under off-design conditions. The active control method introduces fuel or air pulsation during the combustion process through an actuator, combined with a real-time closed-loop control strategy, which can more effectively suppress combustion instability. However, the active control has extremely high requirements for the dynamic response ability of the actuator, and there are still many challenges in achieving precise control under complex working conditions.

[0004] In aeroengines and gas turbines, the annular combustor mostly adopts an annular structure. As a typical axisymmetric structure, the combustion instability of the annular combustor may exhibit various modes such as longitudinal mode and circumferential mode, as Figure 1 shown. Due to the differences in geometric structure and operating conditions, one or more unstable modes may exist simultaneously in different annular combustors. From an acoustic perspective, the circumferential dimension of the annular combustor is the decisive factor, so the combustion instability usually mainly presents as the circumferential mode. The circumferential mode can be further divided into a standing wave mode and a rotating mode, and its pulsation frequency is usually concentrated in the range of 1000 Hz to 2000 Hz, which poses extremely high requirements for the frequency response and dynamic performance of the actuator. In addition, the instability of the annular combustor is also closely related to the regulation path to reach the stable combustion state, that is, there is a significant hysteresis effect, which further increases the complexity of combustion instability control.

[0005] Existing technical solutions and patents for the active control of combustion instability mainly focus on the single longitudinal mode control of a single head (such as Chinese Patent Application CN113418188A), or only achieve the stability control of an annular combustor based on adjusting the air or fuel supply (such as Chinese Patent Application CN101166935A). These technical solutions have limited control effects on complex annular combustors and their multi-modal combustion instabilities, and it is difficult to meet the actual engineering requirements of gas turbines. Especially in annular combustors, due to the complexity of multi-modal and dynamic operating conditions, existing solutions are difficult to achieve flexible and efficient active control. Summary of the Invention

[0006] The purpose of the present invention is to provide an active control system and method for combustion instability of an annular combustor, so as to solve the problem that the existing active control methods for combustion instability of annular combustors have limited control effects on complex annular combustors and their multi-modal combustion instabilities, and it is difficult to meet the actual engineering requirements of gas turbines.

[0007] To achieve the above purpose, the technical solution of the present invention is as follows: The present invention relates to an active control system for combustion instability of an annular combustor, which includes a fuel tank, a fuel pump, and an annular combustor. A number of burners are evenly distributed circumferentially on the annular combustor. The fuel pump is used to transport the fuel in the fuel tank to each burner. It also includes a sensor group, a high-frequency data processing unit, and a high-frequency valve group. The sensor group is used to measure the pulsating pressure and flame heat release rate inside the annular combustor, and transmit the measured data to the high-frequency data processing unit. The high-frequency data processing unit is used to identify the combustion instability mode according to the pulsating pressure and flame heat release rate, and generate corresponding control signals according to the combustion instability mode. The high-frequency valve group includes a plurality of high-frequency valves, which are used to receive the control signals and actively control each burner.

[0008] Preferably, the high-frequency valve group is arranged between the fuel pump and the annular combustor, and each high-frequency valve independently controls the fuel pulse injection of one or more burner heads.

[0009] Preferably, the high-frequency data processing unit identifies the combustion instability mode of the annular combustor according to the feedback value of the pulsating pressure. The combustion instability mode includes a longitudinal mode and a circumferential mode, and the circumferential mode is further divided into a standing wave mode and a rotating mode. The specific method for identifying the combustion instability mode of the annular combustor is: decompose the pulsation of the pulsating pressure along the circumference into two reverse traveling waves. At the circumferential position of the k th flame P k The pulsating pressure can be expressed as: , Among them, is the circumferential average air flow velocity, and are respectively the pressure pulsation amplitudes of the forward traveling wave and the backward traveling wave, R is the average radius of the annular combustor, t is time, is the angular frequency; If the heat release rate pulsation in the circumferential position remains in phase, it is the longitudinal mode; otherwise, it is necessary to determine the heat release rate pulsation amplitudes of the forward traveling wave and the backward traveling wave , and the circumferential average air flow velocity . When and , it is the standing wave mode. When or and , it is the rotating mode.

[0010] Preferably, the high-frequency data processing unit generates corresponding control signals according to the combustion instability mode. Specifically: a) When the combustion instability mode is the longitudinal mode, the high-frequency data processing unit generates the following control signals to the sensor group: The high-frequency valve group adopts a synchronous control method, and the phases and duty cycles of all high-frequency valves are kept consistent, so that the fuel supply of all burners in the circumferential direction maintains the same pulsation amplitude and phase; b) When the combustion instability mode is the standing wave mode, the high-frequency data processing unit generates the following control signals to the sensor group: The high-frequency valve group adopts a standing wave control method, and the phases of the fuel modulation of the burners on the same side of the nodal line are kept consistent, and the phases of the fuel modulation of the burners on both sides of the nodal line differ by 180°. The amplitude of the fuel modulation gradually increases from 0 at the nodal point. As time goes by, the phases of the fuel modulation of each burner change synchronously, so that the pulsation amplitudes of the fuel supply of all burners remain unchanged; c) When the combustion instability mode is the rotating mode, the high-frequency data processing unit generates the following control signals to the sensor group: The high-frequency valve group adopts a rotating control method, and the phases of the fuel modulation of all burners change sequentially in the circumferential direction. The amplitude of the fuel modulation of the burners remains constant. As time goes by, the phases of the fuel modulation of each burner change synchronously, and the amplitude remains unchanged.

[0011] Preferably, the high-frequency valve includes a gas pipeline, a fixed iron core, a moving iron core, a coil, and a valve core; the valve core is directly connected to the moving iron core and extends into the gas pipeline; the fixed iron core is connected to the moving iron core through a spring; the coil is arranged circumferentially around the moving iron core, and the control signal is input into the coil and drives the valve core to open and close through the magnetic effect of the current, including controlling the frequency, phase, and duty cycle of the valve core to open and close.

[0012] Preferably, the sensor group includes a dynamic pressure sensor for measuring pulsating pressure.

[0013] The present invention also relates to an active control method for combustion instability of an annular combustor, which is implemented based on the above-mentioned active control system for combustion instability of an annular combustor, and includes the following steps: S1. The sensor group measures the pulsating pressure and flame heat release rate inside the annular combustor, and transmits the measured data to the high-frequency data processing unit; S2. The high-frequency data processing unit identifies the combustion instability mode according to the pulsating pressure and flame heat release rate, and generates corresponding control signals according to the combustion instability mode; S3. The high-frequency valve group receives the control signals and actively controls each burner.

[0014] Preferably, the specific method for the high-frequency data processing unit in S2 to identify the combustion instability mode according to the pulsating pressure is: decompose the pulsation of the pulsating pressure in the circumferential direction into two reverse traveling waves, and the pulsating pressure of the th flame at the circumferential position of the annular combustor k can be expressed as: P k where, , where is the circumferential average gas flow velocity, and are the pressure pulsation amplitudes of the forward traveling wave and the backward traveling wave respectively, R is the average radius of the annular combustor, t is the time, is the angular frequency; If the pulsation of the flame heat release rate at the circumferential position remains in phase, it is the longitudinal mode; otherwise, it is necessary to determine the heat release rate pulsation amplitudes , and the circumferential average gas flow velocity . When and , it is the standing wave mode, and when or and , it is the rotating mode.

[0015] Preferably, the high-frequency data processing unit in S2 generates corresponding control signals according to the combustion instability mode, specifically: a) When the combustion instability mode is the longitudinal mode, the high-frequency data processing unit generates the following control signals to the sensor group: the high-frequency valve group adopts a synchronous control method, and the phases and duty cycles of all high-frequency valves are kept consistent, so that the fuel supply of all burners in the circumferential direction maintains the same pulsation amplitude and phase; b) When the combustion unstable mode is the standing wave mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts the standing wave control mode, the phase of the fuel modulation of the burners on the same side of the node line is kept consistent, the phase of the fuel modulation of the burners on both sides of the node line is 180° different, and the amplitude of the fuel modulation gradually increases from 0 at the node. As time goes by, the phase of the fuel modulation of each burner changes synchronously, so that the pulsation amplitude of the fuel supply of all burners remains unchanged; c) When the unstable combustion mode is a rotational mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts a rotational control method, the phases of the fuel modulation of all burners change in sequence along the circumferential direction, and the amplitude of the fuel modulation of the burner remains constant. As time goes by, the phases of the fuel modulation of each burner change synchronously, and the amplitude remains unchanged.

[0016] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects: The present invention relates to an annular combustion chamber combustion instability active control, which includes a sensor group, a high-frequency data processing unit and a high-frequency valve group. The sensor group measures the pulsating pressure and flame heat release rate inside the annular combustion chamber, and transmits the measured data to the high-frequency data processing unit. The high-frequency data processing unit identifies the combustion instability mode according to the pulsating pressure and the flame heat release rate, and generates a corresponding control signal according to the combustion instability mode. The high-frequency valve group includes a plurality of high-frequency valves, each of which receives a corresponding control signal and actively controls the corresponding burner. The present invention realizes the modulation of the fuel pulse frequency, phase and amplitude by flexibly adjusting the frequency, phase and duty cycle of the high-frequency valve group, supports a variety of advanced control algorithms through the high-frequency data acquisition and processing unit, can control the high-frequency valve group in linkage, flexibly adjusts the various combustion instability modes of the annular combustion chamber, realizes the precise control of the various combustion instability modes of the annular combustion chamber of the gas turbine, and can effectively reduce the pressure pulsation and heat release pulsation of the annular combustion chamber through the active closed-loop control strategy, suppresses the combustion instability of the annular combustion chamber of the gas turbine, and improves the service life and operation safety of the gas turbine. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a typical combustion instability mode diagram of the annular combustion chamber of the present invention; Figure 2 The control principle diagram of the annular combustion chamber system of the present invention; Figure 3 It is a schematic diagram of the high frequency valve of the present invention; Figure 4 is a control block diagram of the present invention; Figure 5 It is a synchronous control schematic diagram of the present invention; Figure 6Schematic diagram of standing wave control for the present invention; Figure 7 Schematic diagram of rotation control for the present invention.

[0018] Wherein, 1 - fuel tank, 2 - fuel pump, 3 - annular combustion chamber, 31 - burner, 4 - sensor group, 5 - high-frequency data processing unit, 6 - high-frequency valve group, 61 - gas pipeline, 62 - fixed iron core, 63 - moving iron core, 64 - coil, 65 - valve core, 66 - spring. Detailed implementation manners

[0019] To further understand the content of the present invention, the present invention will be described in detail in combination with embodiments. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0020] Embodiment: Refer to the attached Figure 2 As shown, the present invention relates to an active control system for combustion instability of an annular combustion chamber, which includes a fuel tank 1, a fuel pump 2, an annular combustion chamber 3, a sensor group 4, a high-frequency data processing unit 5, and a high-frequency valve group 6.

[0021] A plurality of burners 31 are circumferentially and uniformly distributed on the annular combustion chamber 3. The fuel tank 1 is used to store fuel, and the fuel can be but is not limited to natural gas, hydrogen, ammonia, methanol, diesel, aviation kerosene, etc. The high-frequency valve group 6 is arranged between the fuel pump 2 and the annular combustion chamber 3, and includes a plurality of high-frequency valves. The plurality of high-frequency valves are uniformly or non-uniformly distributed, and each high-frequency valve independently controls the fuel pulse injection at the head of one or more burners 31. One end of the fuel pump 2 is connected to the fuel tank 1 through a fuel pipeline, and the other end is connected to the fuel input ends of the high-frequency valves through a fuel pipeline. The output ends of the high-frequency valves are respectively connected to the burners 31 they control. The fuel pump 2 is used to transport the fuel in the fuel tank 1 to each burner 31. The sensor group 4 is arranged in the annular combustion chamber 3, and the output end of the sensor group 4 is communicatively connected to the input end of the high-frequency data processing unit 5. The sensor group 4 includes a dynamic pressure sensor for measuring pulsating pressure. The sensor group 4 may also include a photomultiplier tube or a high-speed camera for measuring the flame heat release rate, a thermometer and a pressure gauge for measuring the internal temperature and pressure of the annular combustion chamber, etc. The sensor group 4 transmits the measured data to the high-frequency data processing unit 5. The output end of the high-frequency data processing unit 5 is communicatively connected to each high-frequency valve in the high-frequency valve group 6, and is used to identify the combustion instability mode according to the feedback value of the pulsating pressure and generate a corresponding control signal according to the combustion instability mode. The plurality of high-frequency valves are used to receive the control signal and actively control the burners 31 they control.

[0022] Refer to the attached Figure 3As shown in the figure, the high-frequency valve includes a gas pipeline 61, a fixed iron core 62, a moving iron core 63, a coil 64, and a valve core 65; the valve core 65 is directly connected to the moving iron core 63 and extends into the gas pipeline 61; the fixed iron core 62 is connected to the moving iron core 63 through a spring 66; the coil 64 is arranged circumferentially around the moving iron core 63, and a control signal is input into the coil 64 and drives the valve core 65 to open and close through the magnetic effect of the current, including controlling the frequency, phase, and duty cycle of the opening and closing of the valve core 65.

[0023] Refer to the appendix Figure 4 As shown in the figure, the active control method for combustion instability of an annular combustor based on the above control system includes the following steps: S1. The sensor group 4 measures data such as the pulsating pressure, flame heat release rate, pressure, and temperature inside the annular combustor 3, and transmits the measured data to the high-frequency data processing unit 5; S2. The high-frequency data processing unit 5 calculates the deviation amount based on the feedback value of the pulsating pressure and a given signal, and then identifies the combustion instability mode. The combustion instability mode includes a longitudinal mode and a circumferential mode. The circumferential mode is further divided into a standing wave mode and a rotating mode. The specific method for identifying the combustion instability mode of the annular combustor 3 is as follows: decompose the pulsation of the pulsating pressure along the circumference into two reverse traveling waves. The pulsating pressure of the th flame at the circumferential position k of the annular combustor P k can be expressed as: , where is the circumferential average gas flow velocity, and are the pressure pulsation amplitudes of the forward traveling wave and the backward traveling wave respectively, R is the average radius of the annular combustor, t is time, is the angular frequency, e is the natural logarithm, i is the imaginary part of the complex number, which belongs to common mathematical knowledge; If the pulsation of the flame heat release rate remains in phase at the circumferential position, it is the longitudinal mode; otherwise, it is necessary to determine the heat release rate pulsation amplitudes , and the circumferential average gas flow velocity . When and , it is the standing wave mode. When or and , it is the rotating mode.

[0024] After the high-frequency data processing unit 5 identifies the combustion instability mode, it generates corresponding control signals according to the combustion instability mode. The control signals include the opening and closing frequencies, phases, and duty cycles of each high-frequency valve. The specific method is as follows: a) When the combustion instability mode is the longitudinal mode, the high-frequency data processing unit 5 generates the following control signals for the sensor group 4: The high-frequency valve group 6 adopts a synchronous control method, and the phases and duty cycles of all high-frequency valves are kept consistent, so that the fuel supplies of all burners 31 in the circumferential direction maintain the same pulsation amplitude and phase, as Figure 5 shown; b) When the combustion instability mode is the standing wave mode, the high-frequency data processing unit 5 generates the following control signals for the sensor group 4: The high-frequency valve group 6 adopts a standing wave control method. The phases of the fuel modulation of the burners 31 on the same side of the nodal line (the line connecting the points where the amplitude is always zero in the standing wave) are kept consistent, and the phases of the fuel modulation of the burners 31 on both sides of the nodal line differ by 180°. The amplitude of the fuel modulation gradually increases from 0 at the node. As time goes by, the phases of the fuel modulation of each burner 31 change synchronously, so that the pulsation amplitudes of the fuel supplies of all burners 31 remain unchanged, as Figure 6 shown; c) When the combustion instability mode is the rotating mode, the high-frequency data processing unit 5 generates the following control signals for the sensor group 4: The high-frequency valve group 6 adopts a rotating control method. The phases of the fuel modulation of all burners 31 change sequentially in the circumferential direction, and the amplitudes of the fuel modulation of the burners 31 remain constant. As time goes by, the phases of the fuel modulation of each burner 31 change synchronously and the amplitudes remain unchanged, as Figure 7 shown.

[0025] S3. The high-frequency valve group 6 receives the control signals and actively controls each burner 31.

[0026] The above has described the present invention in detail in combination with the embodiments, but the content described is only the preferred embodiments of the present invention and cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. An active control system for combustion instability in an annular combustion chamber, comprising a fuel tank, a fuel pump and an annular combustion chamber, wherein the annular combustion chamber has a plurality of burners evenly distributed around the circumference, and the fuel pump is used to transport the fuel in the fuel tank to each burner, characterized in that: It also includes a sensor group, a high-frequency data processing unit and a high-frequency valve group; the sensor group is used to measure the pulsating pressure and flame heat release rate inside the annular combustion chamber, and transmit the measured data to the high-frequency data processing unit; the high-frequency data processing unit is used to identify the combustion instability mode according to the pulsating pressure and flame heat release rate, and generate corresponding control signals according to the combustion instability mode; the high-frequency valve group includes multiple high-frequency valves, which are used to receive control signals and actively control each burner.

2. The active control system for combustion instability in annular combustion chamber according to claim 1, characterized in that: The high-frequency valve group is arranged between the fuel pump and the annular combustion chamber, and each high-frequency valve independently controls the fuel pulse injection of one or more burner heads.

3. The active control system for combustion instability in annular combustion chamber according to claim 2, characterized in that: The high-frequency data processing unit identifies the combustion instability mode of the annular combustion chamber according to the feedback value of the pulsating pressure. The combustion instability mode includes a longitudinal mode and a circumferential mode. The circumferential mode is further divided into a standing wave mode and a rotating mode. The specific method for identifying the combustion instability mode of the annular combustion chamber is as follows: the pulsation of the pulsating pressure along the circumferential direction is decomposed into two traveling waves in opposite directions. The annular combustion chamber is located at a circumferential position. The k The pulsating pressure of a flame P k It can be expressed as: ， in, is the circumferential average air velocity, and are the pressure pulsation amplitudes of the forward and reverse waves, R is the average radius of the annular combustion chamber, t For time, is the angular frequency; If the pulsation of the heat release rate at the circumferential position remains in phase, it is a longitudinal mode; otherwise, the amplitude of the heat release rate pulsation of the forward and reverse waves needs to be determined. , and the circumferential average air velocity ,when and When is the standing wave mode, or and It is the rotation mode.

4. The active control system for combustion instability in annular combustion chamber according to claim 3, characterized in that: The high-frequency data processing unit generates corresponding control signals according to the unstable combustion mode, specifically: a) when the unstable combustion mode is a longitudinal mode, the high-frequency data processing unit generates the following control signals to the sensor group: the high-frequency valve group adopts a synchronous control mode, and the phases and duty cycles of all high-frequency valves are kept consistent, so that the fuel supply of all burners in the circumferential direction maintains a consistent pulsation amplitude and phase; b) When the combustion unstable mode is the standing wave mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts the standing wave control mode, the phase of the fuel modulation of the burners on the same side of the node line is kept consistent, the phase of the fuel modulation of the burners on both sides of the node line is 180° different, and the amplitude of the fuel modulation gradually increases from 0 at the node. As time goes by, the phase of the fuel modulation of each burner changes synchronously, so that the pulsation amplitude of the fuel supply of all burners remains unchanged; c) When the unstable combustion mode is a rotational mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts a rotational control method, the phases of the fuel modulation of all burners change in sequence along the circumferential direction, and the amplitude of the fuel modulation of the burner remains constant. As time goes by, the phases of the fuel modulation of each burner change synchronously, and the amplitude remains unchanged.

5. The active control system for combustion instability in annular combustion chamber according to claim 2, characterized in that: The high-frequency valve includes a gas pipeline, a fixed iron core, a moving iron core, a coil, and a valve core; the valve core is directly connected to the moving iron core and extends into the gas pipeline; the fixed iron core is connected to the moving iron core through a spring; the coil is arranged in the circumference of the moving iron core, and a control signal is input into the coil and the valve core is driven to open and close through the magnetic effect of the current, including the frequency, phase and duty cycle of controlling the opening and closing of the valve core.

6. The active control system for combustion instability in an annular combustion chamber according to claim 1, characterized in that: The sensor group includes a dynamic pressure sensor for measuring pulsating pressure.

7. A method for actively controlling combustion instability in an annular combustion chamber, which is implemented based on the active control system for combustion instability in an annular combustion chamber according to claim 1, characterized in that: It includes the following steps: S1. The sensor group measures the pulsating pressure and flame heat release rate inside the annular combustion chamber and transmits the measured data to the high-frequency data processing unit; S2. The high-frequency data processing unit identifies the combustion instability mode according to the pulsating pressure and the flame heat release rate, and generates a corresponding control signal according to the combustion instability mode; S3. The high-frequency valve group receives the control signal and actively controls each burner.

8. The method for active control of combustion instability in an annular combustion chamber according to claim 7, characterized in that: The specific method of the S2 high-frequency data processing unit to identify the combustion instability mode according to the pulsating pressure is: decomposing the pulsating pressure along the circumferential direction into two traveling waves in opposite directions, and the annular combustion chamber is located at the circumferential position. The k The pulsating pressure of a flame P k It can be expressed as: ， in, is the circumferential average air velocity, and are the pressure pulsation amplitudes of the forward and reverse waves, R is the average radius of the annular combustion chamber, t For time, is the angular frequency; If the pulsation of the heat release rate at the circumferential position remains in phase, it is a longitudinal mode; otherwise, the amplitude of the heat release rate pulsation of the forward and reverse waves needs to be determined. , and the circumferential average air velocity ,when and When is the standing wave mode, or and It is the rotation mode.

9. The method for actively controlling combustion instability in an annular combustion chamber according to claim 7, characterized in that: The S2 high-frequency data processing unit generates corresponding control signals according to the combustion unstable mode, specifically: a) when the combustion unstable mode is a longitudinal mode, the high-frequency data processing unit generates the following control signals to the sensor group: the high-frequency valve group adopts a synchronous control mode, and the phases and duty cycles of all high-frequency valves are kept consistent, so that the fuel supply of all burners in the circumferential direction maintains a consistent pulsation amplitude and phase; b) When the combustion unstable mode is the standing wave mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts the standing wave control mode, the phase of the fuel modulation of the burners on the same side of the node line is kept consistent, the phase of the fuel modulation of the burners on both sides of the node line is 180° different, and the amplitude of the fuel modulation gradually increases from 0 at the node. As time goes by, the phase of the fuel modulation of each burner changes synchronously, so that the pulsation amplitude of the fuel supply of all burners remains unchanged; c) When the unstable combustion mode is a rotational mode, the high-frequency data processing unit generates the following control signal to the sensor group: the high-frequency valve group adopts a rotational control method, the phases of the fuel modulation of all burners change in sequence along the circumferential direction, and the amplitude of the fuel modulation of the burner remains constant. As time goes by, the phases of the fuel modulation of each burner change synchronously, and the amplitude remains unchanged.

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