An aircraft windshield defogging control protection system and method
By introducing SPDU and electrical system controller into the aircraft windshield heating control system, and utilizing aviation bus and solid-state switch technology, the problems of large size and weight and poor maintainability of traditional systems have been solved. This has enabled comprehensive monitoring of fault signals and simplified human-machine interaction functions, thereby improving the reliability and maintenance efficiency of the system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- AVIC XAC COMMERCIAL AIRCRAFT CO LTD
- Filing Date
- 2023-12-25
- Publication Date
- 2026-06-26
AI Technical Summary
Traditional aircraft windshield heating control systems use independent relay/contactor analog circuits, resulting in large system size and weight, poor maintainability, poor human-machine interaction, and difficulty in achieving comprehensive monitoring and recording of fault signals.
It employs SPDU, electrical system controller and heating control switch, realizes signal transmission through aviation bus, combines solid-state switch technology, integrates AC arc detection, simplifies system architecture, and adopts different heating power modes on the ground and in the air.
It reduces the number of hardware components and system size, improves maintainability and human-computer interaction capabilities, enables comprehensive monitoring and recording of fault signals, and enhances system reliability and fault handling efficiency.
Smart Images
Figure CN117560800B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of aircraft windshield heating, and relates to an aircraft windshield heating control and protection system and method. Background Technology
[0002] Traditionally, each electromechanical system on an aircraft operates independently, requiring a separate windshield heating controller to achieve the windshield heating function. Taking the B737 aircraft as an example, the windshield heating controller component uses relay circuits to achieve heating control functions, including windshield temperature acquisition and monitoring, heating status indication, providing heating power, implementing heating logic within the loop temperature range, and system self-testing. Aircraft have multiple glass components, including the main windshield, side windshields, and ventilation windows. To improve system reliability, multiple heating control components are typically required, which can lead to a large weight and size of the electromechanical system. Using analog circuits makes it difficult to synthesize fault signal logic, requiring manual analysis of collected maintenance data for troubleshooting, especially lacking effective monitoring and judgment methods for arcing faults. The heating circuit uses mechanical relays / contactors for on / off control, which, compared to solid-state power control units, has a shorter lifespan and lower reliability, especially in the vibration environment of an aircraft. It is also prone to contact arcing and rebound, and its size and weight far exceed those of solid-state power control units. The reliability of heating control and protection functions implemented by analog circuits such as relays is limited by the relays, which increases the size and weight of the electromechanical system, makes it difficult to maintain, and usually only allows human-machine interaction by lighting up the corresponding fault alarm lights. The circuits are complex and easily coupled with each other, making it impossible to record the process and synthesize the signals.
[0003] In summary, traditional windshield heating systems require separate windshield heating controllers, and the use of relay / contactor-based analog heating control methods increases the size and weight of the electromechanical system, reduces maintainability, and hinders human-machine interaction. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an aircraft windshield heating control and protection system and method that reduces the number, weight and volume of hardware, simplifies the system architecture, and facilitates the implementation of human-computer interaction functions for prompting and alarming, as well as maintenance information collection and analysis functions.
[0005] To achieve the above objectives, the present invention employs the following technical solution:
[0006] An aircraft windshield heating control and protection system includes an SPDU, an electrical system controller, and a heating control switch;
[0007] The SPDU is electrically connected to the heating element of the aircraft glass and is used to supply power to the heating element. The heating control switch is equipped with a windshield heating switch. Both the SPDU and the heating control switch are interconnected with the electrical system controller via the aviation bus.
[0008] Multiple temperature sensors are installed on the aircraft glass, and the output of the temperature sensors is connected to the electrical system controller.
[0009] Preferably, the aircraft glass is divided into left and right sides, with each side connected to an SPDU and an electrical system controller.
[0010] Preferably, the aircraft glass includes the main windshield, ventilation windows, and side windows.
[0011] Preferably, the electrical system controller is interconnected with the avionics system via an aviation bus signal.
[0012] A heating control and protection method for an aircraft windshield heating control and protection system: When the aircraft is in the air, if the windshield heating switch of the heating control switch is pressed and there is no windshield heating failure state, and the windshield temperature is below 35°C, the electrical system controller sends an on command to the power supply channel of the SPDU to heat the windshield at full power; during the windshield heating process, if the windshield heating switch pops up, the windshield temperature is above 40°C, or a windshield heating failure state is detected, the electrical system controller sends an off command to the power supply channel of the SPDU to cut off the power supply to the heating element.
[0013] Preferably, the windshield heating failure states include temperature sensor failure, heating element or circuit failure, heating circuit arc failure, or over-temperature failure.
[0014] Furthermore, temperature sensor failure occurs when the resistance of all temperature sensors exceeds the set range; heating element or circuit failure occurs when the current of any one of the three-phase heating circuits is less than the normal value for 10 seconds during the heating of the windshield, or when any one phase of the heating circuit triggers the overload or short circuit protection of the SPDU; heating circuit arc failure occurs when the SPDU detects an arc failure in the heating element; and over-temperature failure occurs when the temperature sensor temperature is greater than 60°C and heating continues for 3 cycles.
[0015] Furthermore, any temperature sensor malfunction, heating element or circuit malfunction, heating circuit arc malfunction, or over-temperature malfunction is uploaded to the avionics system via the bus and recorded as maintenance information.
[0016] Furthermore, under normal conditions, only one of the multiple temperature sensors is used. When the electrical system controller detects a fault in the temperature sensor in use, it switches to the next normal temperature sensor.
[0017] Preferably, when the aircraft is on the ground, and the windshield heating switch is pressed and there is no windshield heating failure, if the windshield temperature is below 35°C, the electrical system controller sends an on command to the power supply channel of the SPDU for two consecutive task cycles, and then sends an off command to the power supply channel of the SPDU for two consecutive task cycles to heat the windshield at half power. During the windshield heating process, if the windshield heating switch pops up, the windshield temperature is above 40°C, or a windshield heating failure is detected, the electrical system controller sends an off command to the power supply channel of the SPDU to cut off the power supply to the heating element.
[0018] Compared with the prior art, the present invention has the following beneficial effects:
[0019] The electrical system controller of this invention uses an aviation bus to transmit signals with the SPDU and heating control switch, which increases signal throughput, simplifies the system architecture, and facilitates human-machine interaction functions such as prompting and alarm, as well as comprehensive functions for maintenance information collection and analysis. It uses intelligent power distribution technology based on solid-state switches to replace traditional mechanical switches (relays / contactors) to supply power to the heating resistive load, reducing the number, weight, and volume of hardware. It also integrates AC arc detection function in the windshield heating channel, solving problems such as contact arcing, difficulty in detecting heating arcs, and low reliability.
[0020] Furthermore, considering the significant temperature difference between the ground and air environments, half-power heating on the ground and full-power heating in the air are adopted to avoid overheating and control oscillations that may easily occur on the ground due to excessive heating power. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the structural principle of the aircraft windshield heating control and protection system of the present invention.
[0022] Among them: 1-SPDU; 2-Electrical system controller; 3-Heating control switch; 4-Avionics system; 5-Main windshield; 6-Ventilation window; 7-Side windshield. Detailed Implementation
[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0024] It should be noted that the terms “front,” “back,” “left,” “right,” “up,” and “down” used in the following description refer to the directions shown in the attached diagram, while the terms “inside” and “outside” refer to the directions toward or away from the geometric center of a specific component, respectively.
[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.
[0026] like Figure 1 As shown, the aircraft windshield heating control and protection system of the present invention includes SPDU1, electrical system controller2, heating control switch3 and avionics system4.
[0027] In this invention, SPDU1 refers to a solid-state power controller. SPDU1 is electrically connected to the heating element of the aircraft glass and supplies power to the heating element. The heating control switch 3 is equipped with a windshield heating switch. SPDU1, avionics system 4 and heating control switch 3 are all interconnected with electrical system controller 2 via aviation bus.
[0028] Electrical system controller 2 is the aircraft's own electrical system controller 2. Three temperature sensors are installed on the aircraft glass for backup of 1. The output of the temperature sensors is connected to electrical system controller 2.
[0029] The aircraft windows are divided into left and right sides. Either all the windows can be connected to one SPDU1 and one electrical system controller 2, or the left and right windows can be connected to one SPDU1 and one electrical system controller 2 respectively.
[0030] The aircraft glass described in this embodiment includes the main windshield 5, the ventilation window 6, and the side windshields 7.
[0031] SPDU1 power supply channel integrates arc detection function. When an arc fault is detected, SPDU1 cuts off the power supply to the heating channel and reports the arc fault to the electrical system controller 2. The electrical system controller 2 sends a fault light signal to the heating control switch 3 via the aviation bus and sends alarm and maintenance information to the avionics integrated display system.
[0032] The electrical system controller 2 identifies heating element faults and circuit faults by judging whether the current value of the heating channel of SPDU1 is within the normal range and whether there is channel overload or short circuit protection during the heating state. After a fault occurs, it controls SPDU1 to cut off the heating power supply, lights up the fault light of the heating control switch 3, and sends alarm and maintenance information to the avionics integrated display system.
[0033] When the windshield heating system malfunctions, the system controller will provide fault alarms and maintenance information to the avionics indication and recording system.
[0034] This invention integrates heating control and protection into the electrical system controller 2 in software form. The electrical system controller 2, SPDU1, heating control switch 3, and avionics system 4 all use an aviation bus for signal transmission, which increases signal throughput, simplifies the system architecture, and facilitates the implementation of human-machine interaction functions for prompting alarms, as well as comprehensive functions for maintenance information collection and analysis. It uses intelligent power distribution technology based on solid-state switches to replace traditional mechanical switches (relays / contactors) to supply power to the heating resistive load, and integrates AC arc detection function in the windshield heating channel to solve problems such as contact arcing, difficulty in detecting heating arcs, and low reliability.
[0035] Heating control modes are typically single-power modes. For high-power heating applications, this is usually sufficient to meet the heating requirements of low-temperature environments at high altitudes. However, on the ground, excessive heating power can easily lead to overheating and control oscillations. To address the significant temperature difference between the ground and air environments, a half-power heating mode is used on the ground, while full-power heating is used in the air. Temperature sensor malfunctions, control failures, heating element malfunctions, loop malfunctions, and over-temperature faults are identified and recorded as maintenance information to enhance the system's maintainability. Logic synthesis of various faults generates alarm messages to prompt the unit for appropriate handling.
[0036] Design the following heating control and protection logic based on electrical system controller 2:
[0037] When the aircraft is on the ground, if the windshield heating switch in the heating control switch 3 is pressed (heating), and there is no windshield heating failure, if the temperature of the left main windshield 5 is below 35°C, the electrical system controller 2 (ESC) sends an on command to the power supply channel of SPDU1 for two consecutive task cycles, and then sends an off command to the power supply channel of SPDU1 for two consecutive task cycles, thereby achieving half-power heating of the windshield on the ground (the task cycle of the windshield heating task is 200ms, and one heating cycle is 800ms); when the aircraft is on the ground, if the windshield heating switch is flipped up (no heating), or the windshield temperature is greater than 40°C, or a windshield heating failure is detected, the ESC sends an off command to the power supply channel of SPDU1, cutting off the power supply to the heating element.
[0038] When the aircraft is in the air, if the windshield heating switch is pressed (heating) and there is no windshield heating failure, and the temperature of the left main windshield 5 is below 35°C, the ESC sends an activation command to the power supply channel of SPDU1 to achieve full-power heating of the windshield in the air. During the windshield heating process in the air, if the windshield heating switch pops up (no heating), or the windshield temperature is above 40°C, or a windshield heating failure is detected, the ESC sends a disconnect command to the power supply channel of SPDU1 to cut off the power supply to the heating element.
[0039] The logic for windshield heating failure is as follows: the resistance values of all three temperature sensors (1 with backup 2) exceed the normal range (temperature sensor failure); or, when the windshield is being heated, the current of any one of the three-phase heating circuits is detected to be less than the lower limit of the normal value or higher than the upper limit of the normal value for 5 seconds (heating element or circuit failure); or, any one phase heating circuit triggers the overload or short circuit protection of SPDU1 (heating element or circuit failure); or, SPDU1 detects an arc fault in the heating element (heating circuit arc fault); or, the temperature sensor temperature is greater than 60°C and heating continues for 3 cycles (over-temperature fault).
[0040] Under normal conditions, only one of the three temperature sensors is used. When the electrical system controller 2 detects a fault in the temperature sensor in use, it automatically switches to the next normal temperature sensor.
[0041] A heating element or circuit malfunction, once triggered, will remain marked until the heating control switch 3 is flipped up (heating is disabled), at which point the malfunction will be cleared. A heating circuit arc malfunction, once triggered, will remain marked until the system controller is powered down, i.e., the aircraft is powered down.
[0042] When the windshield heating fails, the signal is transmitted via the bus to the heating control switch 3 to illuminate the fault alarm light, and via the bus to the avionics system 4 to trigger the CAS voice display of the alarm and record maintenance information.
[0043] Temperature sensor malfunction, heating element or circuit malfunction, heating circuit arc malfunction, and over-temperature malfunction will all be uploaded to the avionics system 4 via the bus and recorded as maintenance information.
[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0045] It should be understood that the above description is for illustrative purposes and not for limitation. Many embodiments and applications beyond the provided examples will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of this teaching should not be determined by reference to the above description, but rather by reference to the foregoing claims and the full scope of their equivalents. For purposes of completeness, all articles and references, including patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein in the foregoing claims is not intended as a waiver of that subject matter, nor should it be construed as an indication that the applicant has not considered that subject matter as part of the disclosed inventive subject matter.
Claims
1. A method for controlling and protecting the heating of an aircraft windshield, characterized in that, The method is based on an aircraft windshield heating control and protection system, which includes an SPDU (1), an electrical system controller (2), and a heating control switch (3). SPDU (1) is electrically connected to the heating element of the aircraft glass and is used to supply power to the heating element. The heating control switch (3) is equipped with a windshield heating switch. SPDU (1) and heating control switch (3) are interconnected with the electrical system controller (2) via the aviation bus. Multiple temperature sensors are installed on the aircraft glass, and the output of the temperature sensors is connected to the electrical system controller (2). When the aircraft is in the air, when the windshield heating switch of the heating control switch (3) is pressed and there is no windshield heating failure state, if the windshield temperature is below 35°C, the electrical system controller (2) sends an on command to the power supply channel of the SPDU (1) to heat the windshield at full power; during the windshield heating process, when the windshield heating switch pops up or the windshield temperature is greater than 40°C or a windshield heating failure state is detected, the electrical system controller (2) sends an off command to the power supply channel of the SPDU (1) to cut off the power supply to the heating element.
2. The aircraft windshield heating control and protection method according to claim 1, characterized in that, The aircraft glass is divided into left and right sides, and each side is connected to an SPDU (1) and an electrical system controller (2).
3. The aircraft windshield heating control and protection method according to claim 1, characterized in that, Aircraft glass includes the main windshield (5), ventilation windows (6) and side windows (7).
4. The aircraft windshield heating control and protection method according to claim 1, characterized in that, The electrical system controller (2) is interconnected with the avionics system (4) via aviation bus signals.
5. The aircraft windshield heating control and protection method according to claim 1, characterized in that, Windshield heating failure states include temperature sensor failure, heating element or circuit failure, heating circuit arc failure, or over-temperature failure.
6. The aircraft windshield heating control and protection method according to claim 5, characterized in that, Temperature sensor failure is when the resistance of all temperature sensors exceeds the set range; heating element or circuit failure is when the current of any one of the three-phase heating circuits is less than the lower limit of the normal value or higher than the upper limit of the normal value for 5 seconds when the windshield is heated, or when any one phase heating circuit triggers the overload or short circuit protection of SPDU (1); heating circuit arc failure is when SPDU (1) detects an arc failure of the heating element; over-temperature failure is when the temperature of the temperature sensor is greater than 60°C and the heating continues for 3 cycles.
7. The aircraft windshield heating control and protection method according to claim 5, characterized in that, Any temperature sensor failure, heating element or circuit failure, heating circuit arc failure, or over-temperature failure is uploaded to the avionics system via the aviation bus (4) and recorded in the maintenance information and generates crew warning information.
8. The aircraft windshield heating control and protection method according to claim 5, characterized in that, Under normal conditions, only one of the multiple temperature sensors is used. When the electrical system controller (2) detects a fault in the temperature sensor in use, it switches to the next normal temperature sensor.
9. The aircraft windshield heating control and protection method according to claim 1, characterized in that, When the aircraft is on the ground, if the windshield heating switch is pressed and there is no windshield heating failure, and the windshield temperature is below 35°C, the electrical system controller (2) sends an on command to the power supply channel of the SPDU (1) for two consecutive task cycles, and then sends an off command to the power supply channel of the SPDU (1) for two consecutive task cycles to heat the windshield at half power. During the windshield heating process, if the windshield heating switch pops up, the windshield temperature is greater than 40°C, or a windshield heating failure is detected, the electrical system controller (2) sends an off command to the power supply channel of the SPDU (1) to cut off the power supply to the heating element.