Redundancy fire alarm monitoring method and system suitable for airplane

Abstract

The invention belongs to the technical field of fire alarm monitoring, and particularly relates to a redundancy fire alarm monitoring method and system suitable for an airplane, and the method comprises the steps: 1, determining an infrared original signal response wave band, an ultraviolet original signal response wave band, an infrared intensity threshold value, and an ultraviolet intensity threshold value; 2, determining an engine tail flame shielding judgment basis; and step 3, carrying out redundancy fire alarm monitoring and alarming. According to the invention, the problems of false alarm of fire alarm information and failure in fire alarm reporting of the system caused by the existence of related interference light sources and tail flames because most of the fire alarm detection schemes of the existing aircraft are pneumatic thermosensitive line or optical fire alarm detection are solved, and the high reliability of fire alarm monitoring of the aircraft is ensured.

Description

Technical Field

[0001] This invention belongs to the field of fire alarm monitoring technology, specifically relating to a redundant fire alarm monitoring method and system suitable for aircraft. Background Technology

[0002] Fire protection systems are critical systems for aircraft. Generally, fire protection systems consist of two parts: a fire detection subsystem and a fire suppression subsystem. The fire detection subsystem monitors fire alarm signals in flammable areas of the aircraft and displays, issues, and records fire alarm signals in the cockpit. As the highest level of alarm information for an aircraft, the fire detection subsystem must be reliable and secure. Failure to transmit and display fire alarm information correctly, or the occurrence of false alarms, could lead to serious safety incidents.

[0003] Existing aircraft fire detection solutions mostly employ aerodynamic thermal line detection or optical fire detection. Optical fire detection utilizes the spectral characteristics, radiation intensity, and flicker frequency exhibited during flame combustion to detect the presence of a flame, offering advantages such as a wide detection area and fast response time. However, interfering light sources and exhaust plumes can cause false alarms. Furthermore, if the fire detection circuit malfunctions, a fire occurring at that time will result in the system missing the fire alarm, posing a safety hazard. Summary of the Invention

[0004] The purpose of this invention is to address the problem that existing aircraft fire detection schemes mostly rely on aerodynamic thermal lines or optical fire detection, which can lead to false alarms and missed alarms due to interference from light sources and exhaust plumes. Therefore, this application proposes a redundant fire monitoring method and system for aircraft to ensure high reliability of aircraft fire monitoring.

[0005] The technical solution of the present invention: A method for monitoring redundant fire alarms in aircraft includes the following steps: Step 1: Determine the original infrared signal response band, the original ultraviolet signal response band, the infrared intensity threshold, and the ultraviolet intensity threshold; Step 2: Determine the criteria for judging engine exhaust flame shielding; Step 3: Perform redundant fire alarm monitoring and alerting.

[0006] Furthermore, step 1 specifically includes the following steps: Step 1.1 First, analyze the flammable materials in the aircraft engine compartment: The flammable material is ignited and the flame spectrum is read by a spectrometer to form the original spectrum. Step 1.2 Analyze the interference sources: The spectrometer was placed at various interfering light sources, and the spectral characteristics of the interfering sources were analyzed. The original spectra were initially cropped to obtain the original infrared signal response bands (L1, H1) and the original ultraviolet signal response bands (L2, H2). Step 1.3 Based on the infrared original signal response band (L1, H1) and the ultraviolet original signal response band (L2, H2), select an infrared phototube with a response band of (L1, H1) and an ultraviolet phototube with a response band of (L2, H2) to form a fire alarm detector. Step 1.4: Using the flame recognition algorithm, the original voltage signals obtained by the infrared phototube and ultraviolet phototube through the photoelectric effect are processed. The average value of M sampling points is taken as the sampling time, and the filtered and discrete infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4) are obtained.

[0007] Furthermore, step 2 specifically includes: Step 2.1 Place a spectrometer at a distance X from the engine exhaust flame, with the spectrometer facing the engine exhaust nozzle, and measure and analyze the exhaust flame spectrum. Step 2.2 By analyzing the infrared and ultraviolet intensities in the exhaust flame spectrum, based on the infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4), the number of times the original infrared pulse signal falls within the infrared intensity threshold range (L3, H3) and the number of times the original ultraviolet pulse signal falls within the infrared intensity threshold range (L4, H4) within each Tms are counted, respectively. a and b are the criteria for engine exhaust flame shielding. When the number of original infrared pulse signals is greater than a, the original infrared pulse signal is converted into an infrared signal; when the number of original ultraviolet pulse signals is greater than b, the original ultraviolet pulse signal is converted into an ultraviolet signal. Furthermore, T is 100ms.

[0008] Furthermore, step 3 involves redundant fire alarm monitoring and alerting, specifically including: 3.1 The fire control box uses the flame recognition algorithm module and the engine exhaust flame filtering algorithm module to filter out interference sources in the infrared and ultraviolet raw pulse signals, and obtains the "infrared signal of channel A / B of fire detector X" and the "ultraviolet signal of channel A / B of fire detector X", and sends the above information to the aircraft fire alarm processing unit in real time. 3.2 The fire control box BIT module operates in real time to detect whether the channels between all fire alarm detectors are normal; when the ultraviolet circuits of channels A and B of fire alarm detector X are both detected to be faulty, the fire control box sends the information of "ultraviolet fault of channel A of fire alarm detector X" and "ultraviolet fault of channel B of fire alarm detector X" to the aircraft fire alarm processing unit. 3.3 When a fire occurs, if the "infrared signal of channel A / B of fire detector X" is 1 and the "ultraviolet signal of channel A / B of fire detector X" is 1, the aircraft fire alarm processing unit will determine that the fire alarm conditions are met. 3.4 When the aircraft fire alarm processing unit receives a message from the fire control box indicating that both "fire alarm detector A channel ultraviolet fault" and "fire alarm detector B channel ultraviolet fault" are 1, fire alarm detector X loses its function of collecting and judging ultraviolet fire alarm information and can only judge infrared fire alarms. At this time, when fire alarm detector A or B channel reports an infrared fire alarm, it is determined that "fire alarm detector X single channel fire alarm" is 1. Among all infrared and ultraviolet flame detectors, two or more fire alarm detectors must report a single channel fire alarm at the same time for the aircraft fire alarm processing unit to determine that the fire alarm conditions are met. 3.5 When both the ultraviolet circuits of channels A and B of fire alarm detector X are detected to be faulty, and both the infrared circuits of channels A and B of fire alarm detector X are also detected to be faulty, fire alarm detector X will lose its infrared and ultraviolet fire alarm judgment function, that is, it will be judged that "fire alarm detector X is faulty" as 1. All other fire alarm detectors are working normally, and the system can still work normally at this time. The aircraft loses its fire alarm detection capability only when all fire alarm detectors are faulty. At this time, the aircraft fire alarm processing unit sends out "fire alarm detection failure" as 1 for the aircraft to make a decision.

[0009] A redundant fire alarm monitoring system for aircraft, applied to the method described above, includes several fire detectors arranged in the aircraft engine compartment, a dual-channel fire control box connected to the fire detectors, and an aircraft fire alarm processing unit connected to the dual-channel fire control box; wherein the dual-channel fire control box includes a flame recognition algorithm module for shielding interfering light sources and an engine exhaust flame filtering algorithm module for shielding engine exhaust flames; the aircraft fire alarm processing unit includes a redundant fire alarm monitoring logic module.

[0010] Furthermore, several fire detectors are arranged circumferentially in the flammable area of ​​the aircraft engine compartment.

[0011] Furthermore, the dual-channel fire control box also includes a BIT module, which is used to detect whether the channels between all fire alarm detector circuits are normal.

[0012] The beneficial effects of this invention are as follows: Compared with the prior art, it has the following advantages: a) This invention obtains the infrared original signal response bands (L1, H1) and ultraviolet original signal response bands (L2, H2) through experiments. Combined with the flame recognition algorithm, it can shield various interfering light sources and extract the infrared original pulse signal and ultraviolet original pulse signal that meet the requirements. b) The infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4) are obtained through engine exhaust flame tests. Then, the engine exhaust flame is shielded by the engine exhaust flame filtering algorithm, which can convert the optical signal characteristics in nature into infrared and ultraviolet fire alarm signals for monitoring engine compartment fire. c) An architecture consisting of X separate fire detectors and one fire control box is adopted, with the X fire detectors arranged circumferentially in the flammable area of ​​an aircraft cabin. Each fire detector can collect infrared and ultraviolet signals from the flame. The fire control box integrates and converts the raw infrared and ultraviolet signals collected by the fire detectors into infrared and ultraviolet fire alarms, respectively. The fire control box can perform real-time BIT detection between the fire detectors and the fire control box. If the self-detection fails, it outputs an infrared circuit fault or an ultraviolet circuit fault. d) The signal transmission channel between the aircraft fire alarm processing unit and the fire control box is a dual-redundant RS-422 bus communication. The signals sent by a single fire detector to the aircraft fire alarm processing unit through the fire control box include information such as A / B channel infrared fire alarm, A / B channel ultraviolet fire alarm, A / B channel infrared circuit fault, and A / B channel ultraviolet circuit fault. e) The aircraft fire alarm processing unit receives information such as infrared fire alarm, ultraviolet fire alarm, infrared circuit fault, and ultraviolet circuit fault from the fire control box. Through multi-parameter comprehensive voting and fire alarm judgment logic settings, it further enhances the system's ability to prevent false alarms and generates an alarm list for the pilot. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of engine exhaust flame spectrum measurement; Figure 2 This is a diagram of the redundancy fire alarm monitoring system architecture of the present invention; Figure 3 This is a flowchart of the redundant fire alarm monitoring method of the present invention. Detailed Implementation

[0014] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0015] One embodiment of the present invention provides a method for monitoring redundant fire alarms in aircraft, comprising the following steps: Step 1: Determine the original infrared signal response band, the original ultraviolet signal response band, the infrared intensity threshold, and the ultraviolet intensity threshold; including the following steps: Step 1.1 First, analyze the flammable materials in the aircraft engine compartment: The flammable material is ignited and the flame spectrum is read by a spectrometer to form the original spectrum. Step 1.2 Analyze the interference sources: The spectrometer was placed at various interfering light sources, and the spectral characteristics of the interfering sources were analyzed. The original spectra were initially cropped to obtain the original infrared signal response bands (L1, H1) and the original ultraviolet signal response bands (L2, H2). Step 1.3 Based on the infrared original signal response band (L1, H1) and the ultraviolet original signal response band (L2, H2), select an infrared phototube with a response band of (L1, H1) and an ultraviolet phototube with a response band of (L2, H2) to form a fire alarm detector. Step 1.4: Using the flame recognition algorithm, the original voltage signals obtained by the infrared phototube and ultraviolet phototube through the photoelectric effect are processed. The average value of M sampling points is taken as the sampling time, and the filtered and discrete infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4) are obtained.

[0016] Step 2: Determine the criteria for judging engine exhaust flame shielding; specifically including: Step 2.1 Place a spectrometer at a distance X from the engine exhaust flame, with the spectrometer facing the engine exhaust nozzle, and measure and analyze the exhaust flame spectrum. Step 2.2: By analyzing the infrared and ultraviolet intensities in the exhaust flame spectrum, based on the infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4), the number of times the original infrared pulse signal falls within the infrared intensity threshold range (L3, H3) and the number of times the original ultraviolet pulse signal falls within the infrared intensity threshold range (L4, H4) within each Tms are counted, respectively. a and b are the criteria for engine exhaust flame shielding. When the number of original infrared pulse signals is greater than a, the original infrared pulse signal is converted into an infrared signal; when the number of original ultraviolet pulse signals is greater than b, the original ultraviolet pulse signal is converted into an ultraviolet signal. T is 100ms.

[0017] Step 3: Perform redundant fire alarm monitoring and alerting, specifically including: 3.1 The fire control box uses the flame recognition algorithm module and the engine exhaust flame filtering algorithm module to filter out interference sources in the infrared and ultraviolet raw pulse signals, and obtains the "infrared signal of channel A / B of fire detector X" and the "ultraviolet signal of channel A / B of fire detector X", and sends the above information to the aircraft fire alarm processing unit in real time. 3.2 The fire control box BIT module operates in real time to detect whether the channels between all fire alarm detectors are normal; when the ultraviolet circuits of channels A and B of fire alarm detector X are both detected to be faulty, the fire control box sends the information of "ultraviolet fault of channel A of fire alarm detector X" and "ultraviolet fault of channel B of fire alarm detector X" to the aircraft fire alarm processing unit. 3.3 When a fire occurs, if the "infrared signal of channel A / B of fire detector X" is 1 and the "ultraviolet signal of channel A / B of fire detector X" is 1, the aircraft fire alarm processing unit will determine that the fire alarm conditions are met. 3.4 When the aircraft fire alarm processing unit receives a message from the fire control box indicating that both "fire alarm detector A channel ultraviolet fault" and "fire alarm detector B channel ultraviolet fault" are 1, fire alarm detector X loses its function of collecting and judging ultraviolet fire alarm information and can only judge infrared fire alarms. At this time, when fire alarm detector A or B channel reports an infrared fire alarm, it is determined that "fire alarm detector X single channel fire alarm" is 1. Among all infrared and ultraviolet flame detectors, two or more fire alarm detectors must report a single channel fire alarm at the same time for the aircraft fire alarm processing unit to determine that the fire alarm conditions are met. 3.5 When both the ultraviolet circuits of channels A and B of fire alarm detector X are detected to be faulty, and both the infrared circuits of channels A and B of fire alarm detector X are also detected to be faulty, fire alarm detector X will lose its infrared and ultraviolet fire alarm judgment function, that is, it will be judged that "fire alarm detector X is faulty" as 1. All other fire alarm detectors are working normally, and the system can still work normally at this time. The aircraft loses its fire alarm detection capability only when all fire alarm detectors are faulty. At this time, the aircraft fire alarm processing unit sends out "fire alarm detection failure" as 1 for the aircraft to make a decision.

[0018] The second embodiment of the present invention also provides a method for monitoring redundant fire alarms in aircraft, comprising: Step 1: Determine the original infrared signal response band, the original ultraviolet signal response band, the infrared intensity threshold, and the ultraviolet intensity threshold; Step 1.1 First, analyze the flammable materials in the aircraft engine compartment: ignite the flammable materials and read the flame spectrum using a spectrometer to form the original spectrum; Step 1.2 Analyze the interference sources (including ground sunlight radiation, electric welding, and various light sources). Place the spectrometer at various interference light sources, analyze the spectral characteristics of the interference sources, and perform initial cropping on the original spectrum to obtain the original infrared signal response bands (L1, H1) and the original ultraviolet signal response bands (L2, H2). Step 1.3 Based on the original infrared signal response band (L1, H1) and the original ultraviolet signal response band (L2, H2), select an infrared phototube with a response band of (L1, H1) and an ultraviolet phototube with a response band of (L2, H2). Step 1.4: Using the flame recognition algorithm, the original voltage signals obtained by the infrared phototube and ultraviolet phototube through the photoelectric effect are sampled with Δt (unit: ms) as the sampling time. The average value of M sampling points is taken to obtain the filtered and discrete infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4).

[0019] Step 2: Determine the engine exhaust smoke shielding criterion using an engine exhaust smoke filtering algorithm: Step 2.1 Position a spectrometer at a distance X from the engine exhaust flame, keeping it within a safe range of the exhaust flame. Position the spectrometer sideways towards the engine exhaust nozzle to measure and analyze the exhaust flame spectrum. The installation diagram is shown below. Figure 1 As shown.

[0020] Step 2.2: By analyzing the infrared and ultraviolet intensities in the exhaust plume spectrum, infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4) are set. The number of times the original infrared pulse signal falls within the infrared intensity threshold range (L3, H3) and the number of times the original ultraviolet pulse signal falls within the infrared intensity threshold range (L4, H4) within 100ms are counted, respectively. a and b are the criteria for engine exhaust plume shielding.

[0021] Step 3: Design the architecture of the redundant fire alarm monitoring system Step 3.1 The system architecture is set as X separate fire detectors, 1 dual-redundant fire control box and 1 aircraft fire alarm processing unit; Step 3.2: X fire detectors are arranged facing each other inside the cabin, serving as backups for each other, and acting as fire alarm information collection channels; Step 3.3 The fire control box, as the processing and algorithm center for fire alarm data, adopts a dual-redundant hardware design (corresponding to channels A and B). Its channels A and B are each independently responsible for converting the raw infrared and ultraviolet pulse signals collected by the fire detector into infrared and ultraviolet fire alarm information through flame recognition algorithm and engine exhaust flame filtering algorithm. At the same time, the fire control box performs real-time self-testing with the fire detector circuit and analyzes and processes fault information. Step 3.4: The fault and fire alarm information processed by the fire control box is sent to the aircraft fire alarm processing unit via a dual-redundancy RS-422 bus. The aircraft fire alarm processing unit, as the platform for integrated aircraft-level fire alarm information, comprehensively processes the finished-level alarm and fault information sent by the fire control box. The dual-redundancy fire alarm monitoring architecture design is as follows: Figure 2 As shown.

[0022] Step 4: Redundancy Fire Alarm Monitoring Step 4.1 Taking Fire Detector No. 1 as an example, the fire control box obtains the "Infrared Signal of Channel A / B of Fire Detector No. 1" and "Ultraviolet Signal of Channel A / B of Fire Detector No. 1" by using the tail flame recognition algorithm according to the infrared intensity threshold (L3, H3) and ultraviolet intensity threshold (L4, H4) of the original infrared and ultraviolet pulse signals. Then, the above information is sent to the aircraft fire alarm processing unit in real time through the dual-redundancy RS-422 bus communication. Step 4.2 The fire control box performs real-time BIT to check whether the channels between the X-channel fire detectors are normal. When a fault is detected in both the A and B channels of fire detector No. 1, the fire detector will send the "Fire Detector No. 1 A Channel Ultraviolet Fault" and "Fire Detector No. 1 B Channel Ultraviolet Fault" information to the aircraft fire alarm processing unit through the dual-redundancy RS-422 bus communication. Step 4.3 Taking Fire Detector No. 1 as an example, when a fire occurs, the "Infrared Signal of Channel A / B of Fire Detector No. 1" is 1 and the "Ultraviolet Signal of Channel A / B of Fire Detector No. 1" is 1, and the aircraft fire alarm processing unit determines that the fire alarm conditions are met.

[0023] Step 4.4 When the aircraft fire alarm processing unit receives a "Channel A Ultraviolet Fault of Fire Detector 1" and a "Channel B Ultraviolet Fault of Fire Detector 1" message from the fire control box, Fire Detector 1 loses its function of collecting and judging ultraviolet fire alarm information and can only judge infrared fire alarms. At this time, when Fire Detector 1 reports an infrared fire alarm via Channel A or Channel B, it is determined that "Fire Detector 1 Single Channel Fire Alarm" is 1. Among the infrared and ultraviolet flame detectors 1 to X, two or more fire detectors must simultaneously report a single channel fire alarm for the aircraft fire alarm processing unit to further comprehensively judge whether the fire alarm conditions are met. Step 4.5 When both the ultraviolet circuits of channels A and B of fire detector No. 1 and the infrared circuits of channels A and B of fire detector No. 1 are detected to be faulty, fire detector No. 1 loses its infrared and ultraviolet fire alarm judgment function, and is judged as "fire detector No. 1 faulty" as 1. Since fire detectors No. 2 to No. X are all working normally, the fire alarm detection subsystem can still work normally at this time. The aircraft loses its fire alarm detection capability only when all fire detectors No. 1 to No. X are faulty. At this time, the aircraft fire alarm processing unit sends out "fire alarm detection failure" as 1 for the aircraft to make a decision. The redundancy fire alarm monitoring logic is shown in Table 1.

[0024] (0 is invalid, 1 is valid, X represents a fault)

[0025] A third embodiment of the present invention provides a redundant fire alarm monitoring system suitable for aircraft, applied to the method described herein. The system includes several fire detectors arranged in the aircraft engine compartment, a dual-channel fire control box connected to the fire detectors, and an aircraft fire alarm processing unit connected to the dual-channel fire control box. The dual-channel fire control box includes a flame recognition algorithm module for shielding interfering light sources and an engine exhaust flame filtering algorithm module for shielding engine exhaust flames. The aircraft fire alarm processing unit includes a redundant fire alarm monitoring logic module. The dual-channel fire control box also includes a BIT module for detecting whether the channels between all fire detector loops are normal.

[0026] Several fire detectors are arranged circumferentially in the flammable area of ​​the aircraft engine compartment.

[0027] This invention utilizes flame recognition algorithms and engine exhaust flame filtering algorithms to shield various interference signals and identify genuine red and ultraviolet flame information. The architecture employs a redundant fire detector, a dual-redundant fire control box, and a dual-redundant signal transmission scheme between the fire control box and the aircraft fire alarm processing unit. Finally, through a redundant fire alarm monitoring method applicable to a specific aircraft type, and by integrating multi-parameter voting and fire alarm judgment logic settings, the system's false alarm prevention capability is further enhanced. This significantly improves system reliability and reduces the likelihood of missed fire alarms, while maintaining a wide optical fire alarm detection area and fast response time.

[0028] The above description is merely a specific embodiment of the present invention, providing a detailed description of the invention. Parts not covered herein are conventional techniques. However, the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for monitoring redundant fire alarms in aircraft, characterized in that, Includes the following steps: Step 1: Determine the original infrared signal response band, the original ultraviolet signal response band, the infrared intensity threshold, and the ultraviolet intensity threshold; Step 2: Determine the criteria for judging engine exhaust flame shielding; Step 3: Perform redundant fire alarm monitoring and alerting.

2. The method according to claim 1, characterized in that, Step 1 specifically includes the following steps: Step 1.1 First, analyze the flammable materials in the aircraft engine compartment: The flammable material is ignited and the flame spectrum is read by a spectrometer to form the original spectrum. Step 1.2 Analyze the interference sources: The spectrometer was placed at various interfering light sources, and the spectral characteristics of the interfering sources were analyzed. The original spectra were initially cropped to obtain the original infrared signal response bands (L1, H1) and the original ultraviolet signal response bands (L2, H2). Step 1.3 Based on the infrared original signal response band (L1, H1) and the ultraviolet original signal response band (L2, H2), select an infrared phototube with a response band of (L1, H1) and an ultraviolet phototube with a response band of (L2, H2) to form a fire alarm detector. Step 1.4: Using the flame recognition algorithm, the original voltage signals obtained by the infrared phototube and ultraviolet phototube through the photoelectric effect are processed. The average value of M sampling points is taken as the sampling time, and the filtered and discrete infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4) are obtained.

3. The method according to claim 2, characterized in that, Step 2 specifically includes: Step 2.1 Place a spectrometer at a distance X from the engine exhaust flame, with the spectrometer facing the engine exhaust nozzle, and measure and analyze the exhaust flame spectrum. Step 2.2 By analyzing the infrared and ultraviolet intensities in the exhaust flame spectrum, based on the infrared intensity thresholds (L3, H3) and ultraviolet intensity thresholds (L4, H4), the number of times the original infrared pulse signal falls within the infrared intensity threshold range (L3, H3) and the number of times the original ultraviolet pulse signal falls within the infrared intensity threshold range (L4, H4) within each Tms are counted, respectively. a and b are the criteria for engine exhaust flame shielding. When the number of original infrared pulse signals is greater than a, the original infrared pulse signal is converted into an infrared signal; when the number of original ultraviolet pulse signals is greater than b, the original ultraviolet pulse signal is converted into an ultraviolet signal.

4. The method according to claim 3, characterized in that, T is 100ms.

5. The method according to claim 4, characterized in that, Step 3 involves redundant fire alarm monitoring and alerting, specifically including: 3.1 The fire control box uses the flame recognition algorithm module and the engine exhaust flame filtering algorithm module to filter out interference sources in the infrared and ultraviolet raw pulse signals, and obtains the "infrared signal of channel A / B of fire detector X" and the "ultraviolet signal of channel A / B of fire detector X", and sends the above information to the aircraft fire alarm processing unit in real time. 3.2 The fire control box BIT module operates in real time to detect whether the channels between all fire alarm detectors are normal; when the ultraviolet circuits of channels A and B of fire alarm detector X are both detected to be faulty, the fire control box sends the information "ultraviolet fault of channel A of fire alarm detector X" and "ultraviolet fault of channel B of fire alarm detector X" to the aircraft fire alarm processing unit. 3.3 When a fire occurs, if the "infrared signal of channel A / B of fire detector X" is 1 and the "ultraviolet signal of channel A / B of fire detector X" is 1, the aircraft fire alarm processing unit will determine that the fire alarm conditions are met. 3.4 When the aircraft fire alarm processing unit receives a message from the fire control box indicating that both "Fire alarm detector A channel UV fault" and "Fire alarm detector B channel UV fault" are 1, fire alarm detector X loses its ability to collect and judge UV fire alarm information and can only judge infrared fire alarms. At this time, when fire alarm detector A or B channel reports an infrared fire alarm, it is determined that "Fire alarm detector X single channel fire alarm" is 1. Among all infrared and ultraviolet flame detectors, two or more fire alarm detectors must report a single channel fire alarm simultaneously for the aircraft fire alarm processing unit to determine that the fire alarm conditions are met. 3.5 When both the ultraviolet circuits of channels A and B of fire alarm detector X are detected to be faulty, and both the infrared circuits of channels A and B of fire alarm detector X are also detected to be faulty, fire alarm detector X will lose its infrared and ultraviolet fire alarm judgment function, that is, it will be judged that "fire alarm detector X is faulty" as 1. All other fire alarm detectors are working normally, and the system can still work normally at this time. The aircraft loses its fire alarm detection capability only when all fire alarm detectors are faulty. At this time, the aircraft fire alarm processing unit sends out "fire alarm detection failure" as 1 for the aircraft to make a decision.

6. A redundant fire alarm monitoring system for aircraft, applied to the method of claim 5, characterized in that, The system includes several fire detectors arranged in the aircraft engine compartment, a dual-channel fire control box connected to the fire detectors, and an aircraft fire alarm processing unit connected to the dual-channel fire control box. The dual-channel fire control box includes a flame recognition algorithm module for shielding interfering light sources and an engine exhaust flame filtering algorithm module for shielding engine exhaust flames. The aircraft fire alarm processing unit includes a redundant fire alarm monitoring logic module.

7. The redundancy fire alarm monitoring system for aircraft according to claim 6, characterized in that, Several fire detectors are arranged circumferentially in the flammable area of ​​the aircraft engine compartment.

8. The redundancy fire alarm monitoring system for aircraft according to claim 6, characterized in that, The dual-channel fire control box also includes a BIT module, which is used to detect whether the channels between all fire alarm detector circuits are normal.

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