Fault diagnosis method for pneumatic cabin pressure regulator under ultrahigh cabin excess pressure condition

Abstract

The invention relates to the technical field of aircraft environment control, in particular to a fault diagnosis method for a pneumatic cabin pressure regulator under the condition of ultrahigh cabin excess pressure. A control mechanism and an execution mechanism of the pneumatic cabin pressure regulator are in indirect control, a real-time proportion value is obtained by setting proportion threshold values and collecting atmospheric static pressure, cabin pressure and control cavity pressure, and the two threshold values are compared, so that a fault diagnosis conclusion is obtained. By means of the fault diagnosis method, whether the cabin pressure regulator breaks down or not can be rapidly positioned, it is guaranteed that the fault position is accurately removed, the fault analysis and confirmation time is shortened, the troubleshooting efficiency is improved, the situation that the fault cannot be removed for a long time is avoided, and the perfectness ratio of an airplane is increased.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft environment control, and in particular to a fault diagnosis method for a pneumatic cabin pressure regulator under the condition of excessive cabin residual pressure. Background Art

[0002] The current pneumatic cabin pressure regulator is a purely mechanical type. The controller sends out a pneumatic control signal, and the exhaust valve (actuator) adjusts the opening of the exhaust valve after receiving the pneumatic control signal to achieve the purpose of regulating the cabin pressure. Since there is no monitoring, processing and analysis of relevant signals, when the cabin residual pressure of the aircraft is too high, the system does not have the function of online fault diagnosis.

[0003] When the product is working with the aircraft and the cabin residual pressure is too high, in order to eliminate the fault, it is necessary to check all the related systems, products, and pipelines on the aircraft to find the cause of the fault. The process is basically as follows: disassemble and check the connecting pipelines on the aircraft. If there is no abnormality, the product needs to be removed and returned to the manufacturer for inspection. If the cause of the fault has not been found, it is necessary to check other parts of the aircraft again. In short, the entire troubleshooting process is basically an investigation. If the fault status is destroyed during the ground disassembly and replacement process, it is possible that the cause of the fault cannot be found, which in turn affects the troubleshooting. In short, the current on-board troubleshooting cycle is very long, and many times, the fault is difficult to locate, which causes great trouble to the troubleshooting work. Summary of the invention

[0004] Purpose of the Invention

[0005] An online fault diagnosis method is proposed. When an excessive residual pressure fault occurs in the aircraft cabin, the fault diagnosis method can quickly determine whether the cabin pressure regulator is at fault, thereby achieving the purpose of rapid troubleshooting.

[0006] Technical Solution

[0007] A fault diagnosis method for a pneumatic cabin pressure regulator under excessive cabin residual pressure is provided. The control mechanism and the actuator of the pneumatic cabin pressure regulator are indirectly controlled. A proportional threshold is set, atmospheric static pressure, cabin pressure, and control cavity pressure are collected to obtain a real-time proportional value, and the sizes of the two thresholds are compared to obtain a fault diagnosis conclusion.

[0008] Further, the following steps are included:

[0009] Step 1: Set the proportional threshold value M; collect the atmospheric static pressure P in real time h , Cabin pressure P C , the control chamber pressure P of the pneumatic integrated cabin pressure regulator A and sending the collected signal to the fault diagnosis device;

[0010] Step 2: The computer unit performs calculations according to the following formula:

[0011]

[0012] Get the real-time ratio value m;

[0013] Step 3: When the aircraft is in the free ventilation area or the absolute pressure adjustment area, the real-time proportional value m is judged.

[0014] 1) If the real-time proportional value m in the free ventilation zone is greater than the proportional threshold value M, the cause of the excessive residual pressure failure may be a product failure;

[0015] 2) If the real-time ratio value m of the free ventilation area and the absolute pressure adjustment area is greater than the ratio threshold value M, the cause of the excessive residual pressure fault is a product fault;

[0016] 3) If the real-time ratio value m between the free ventilation area and the absolute pressure adjustment area is less than the ratio threshold value M, the cause of the excessive residual pressure fault is not a product fault.

[0017] Furthermore, the ratio threshold M is 10.

[0018] Furthermore, the static atmospheric pressure P h , Cabin pressure P C , the exhaust valve control chamber pressure P of the pneumatic integrated cabin pressure regulator A The real-time acquisition cycle does not exceed 40ms.

[0019] Furthermore, the cabin pressure P C Collected by the cabin pressure sensor.

[0020] Furthermore, the static atmospheric pressure P h The pressure is collected by the pressure sensor of the pneumatic integrated cabin pressure regulator.

[0021] Furthermore, the control chamber pressure P A The pressure is collected by the pressure sensor of the pneumatic integrated cabin pressure regulator.

[0022] The beneficial effects of this application are:

[0023] The fault diagnosis method of the present invention can realize rapid location determination of whether the cabin pressure regulator is faulty, ensure accurate elimination of the fault location, reduce fault analysis confirmation time, improve troubleshooting efficiency, avoid the problem of long-term failure to eliminate the fault, and increase the aircraft availability rate. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the diagnostic method. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the implementation of the present invention clearer, the technical scheme in the embodiment of the present invention will be described in more detail in combination with the embodiment of the present invention. In the example, the same or similar reference numerals throughout represent the same or similar originals or elements with the same or similar functions. The described embodiments are part of the embodiments of the present invention, not all of them. The embodiments described below by reference are exemplary and intended to be used to explain the present invention, and should not be construed as limitations on the present invention. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present invention. The following is a detailed description in combination with the embodiments of the present invention.

[0026] Core invention: Propose a fault diagnosis model by real-time monitoring of system signals A fault diagnosis logic is proposed for the excessive cabin residual pressure failure mode.

[0027] Secondary invention point 1: A sensor (A) is set on the pneumatic pressure regulator to monitor the product control chamber pressure signal P in real time A , and upload it to the fault diagnostics tool.

[0028] Secondary invention point 2: A sensor (B) is set on the pneumatic pressure regulator to monitor the atmospheric static pressure signal P felt by the product in real time h , and upload it to the fault diagnostics tool.

[0029] Secondary invention point 3: Setting up a fault diagnostic device to receive the atmospheric altitude signal h and cabin pressure signal P collected by the aircraft system C , and receiving the above collected product control chamber pressure P A and atmospheric static pressure P h .

[0030] Secondary invention point 4: After the fault diagnostic device receives each signal, it uses a predetermined fault diagnosis model Perform calculations.

[0031] Secondary invention point 5: The result of the operation according to the predetermined fault diagnosis model is compared with the logical threshold.

[0032] Minor invention point 6: In the free ventilation area, when the calculation result is greater than the logical threshold, it may be a product failure.

[0033] Secondary invention point 7: In the free ventilation area and the absolute pressure adjustment area, when the calculation results are greater than the logical threshold, it is judged as a product failure.

[0034] Secondary invention point 8: In the free ventilation area and the absolute pressure adjustment area, when the calculation results are both less than the logical threshold, it is judged that the product is working normally.

[0035] A method for diagnosing a fault of a pneumatic cabin pressure regulator when the cabin residual pressure is too high is provided, wherein the control mechanism and the actuator of the pneumatic cabin pressure regulator are indirectly controlled, and the method comprises the following steps:

[0036] Step 1: Set up sensors A and B on the cabin regulator product to collect the product control chamber pressure P respectively. A and atmospheric static pressure P h

[0037] Step 2: Set up a fault diagnostic device to receive the atmospheric altitude signal h and the cabin pressure signal P collected by the aircraft system. C , and receiving the above collected product control chamber pressure P A and atmospheric static pressure P h .

[0038] Step 3: The fault diagnostic device performs fault diagnosis according to the predetermined fault diagnosis model and fault diagnosis logic.

[0039] Fault diagnosis model The process of obtaining: the internal pneumatic signal P of the product A The cabin pressure regulator is a device that adjusts the pressure in the control chamber P. A The size of the cabin pressure Pc is indirectly adjusted, and the change trends of the two are consistent, and the difference (P C -P A ) is very small, about (1~3) kPa. As the atmospheric altitude rises, the cabin residual pressure gradually increases, and (P C -P A ) is almost unchanged, but in different stages, P A There is a certain regular change in the degree of proximity to Ph or Pc: 1) In the free ventilation area (0-2000) m, the control chamber pressure P A With atmospheric pressure P H Almost equal, that is (P A -P h ) approaches zero, and (P C -P A ) is greater than 1 kPa, so The ratio m approaches 0; 2) The flight altitude increases, and when it approaches 2400m, (P A -P h) begins to increase slowly, and in the absolute pressure regulation zone (2400-7000)m, as the altitude increases, (P A -P h ) continued to increase and subsequently exceeded (P C -P A ) several times; 3) After the flight altitude rises to 7000m until the ceiling, it belongs to the residual pressure adjustment range. Within this range, (P A -P h ) increases sharply with the increase of flight altitude. Therefore, according to (P A -P h ) and (P C -P A ) can be monitored at different heights. The ratio m is used to determine the cause of the cabin pressure failure.

[0040] Fault diagnosis logic: When the aircraft is in the free ventilation area or the absolute pressure adjustment area, the real-time proportional value m is judged: 1) If the real-time proportional value m in the free ventilation area is greater than the proportional threshold value M, the cause of the excessive residual pressure fault may be a product fault; 2) If the real-time proportional value m in the free ventilation area and the absolute pressure adjustment area is greater than the proportional threshold value M, the cause of the excessive residual pressure fault is a product fault; 3) If the real-time proportional value m in the free ventilation area and the absolute pressure adjustment area is less than the proportional threshold value M, the cause of the excessive residual pressure fault is not a product fault.

[0041] The ratio threshold M is 10.

[0042] It is understood by those skilled in the art that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as the general understanding of ordinary technicians in the field to which the present invention belongs. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and unless defined as here, will not be interpreted with idealized or overly formal meanings. The specific implementation methods described above further describe the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Within the spirit and principle of the present invention, any technician familiar with the profession may use the above disclosed technical content to change or modify it into an equivalent embodiment of equivalent changes for application in other fields, but any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the technical solution content of the present invention, any modification, equivalent replacement, improvement, etc., made according to the technical essence of the present invention, should be included in the protection scope of the present invention.

Claims

1. A method for diagnosing a fault of a pneumatic cabin pressure regulator under the condition of excessive cabin residual pressure, characterized in that: The control mechanism and the actuator of the pneumatic cabin pressure regulator are indirectly controlled. By setting a proportional threshold, collecting atmospheric static pressure, cabin pressure, and control cavity pressure to obtain a real-time proportional value, and comparing the sizes of the two thresholds, a fault diagnosis conclusion is obtained.

2. The diagnostic method according to claim 1, characterized in that The steps include: Step 1: Set the proportional threshold value M; collect the atmospheric static pressure P in real time h , Cabin pressure P C , the control chamber pressure P of the pneumatic integrated cabin pressure regulator A and sends the collected signals to the fault diagnosis device.

3. The diagnostic method according to claim 2, characterized in that Step 2: The computer unit performs calculations according to the following formula: Get the real-time ratio value m.

4. The diagnostic method according to claim 3, characterized in that Step 3: When the aircraft is in the free ventilation area or the absolute pressure adjustment area, the real-time proportional value m is judged. 1) If the real-time proportional value m in the free ventilation zone is greater than the proportional threshold value M, the cause of the excessive residual pressure failure may be a product failure; 2) If the real-time ratio value m of the free ventilation area and the absolute pressure adjustment area is greater than the ratio threshold value M, the cause of the excessive residual pressure fault is a product fault; 3) If the real-time ratio value m between the free ventilation area and the absolute pressure adjustment area is less than the ratio threshold value M, the cause of the excessive residual pressure fault is not a product fault.

5. The diagnostic method according to claim 4, characterized in that The ratio threshold M is 10.

6. The diagnostic method according to claim 5, characterized in that Atmospheric static pressure P h , Cabin pressure P C , the exhaust valve control chamber pressure P of the pneumatic integrated cabin pressure regulator A The real-time acquisition cycle does not exceed 40ms.

7. The diagnostic method according to claim 6, characterized in that Cabin pressure P C Collected by the cabin pressure sensor.

8. The diagnostic method according to claim 7, characterized in that Atmospheric static pressure P h The pressure is collected by the pressure sensor of the pneumatic integrated cabin pressure regulator.

9. The diagnostic method according to claim 8, characterized in that Control chamber pressure P A The pressure is collected by the pressure sensor of the pneumatic integrated cabin pressure regulator.

Images