A triple-redundancy aircraft brake control system

Abstract

The present invention relates to a triple-redundancy aircraft brake control system, which mainly includes a normal brake system and an emergency brake system. The normal brake system adopts electrical dual redundancy and hydraulic dual redundancy, and the emergency brake system adopts electronic control single redundancy. The normal brake system and the emergency brake system are in a parallel relationship. By default, the normal brake system implements wheel braking. When the normal brake system fails, the emergency brake system ensures wheel braking. The normal brake system is composed of a command sensor, a control module, an integrated control valve, an integrated conversion valve, a speed sensor, a conversion valve, and an energy conversion valve. The emergency brake system adopts an electro-hydraulic control method and is composed of an accumulator, an emergency electro-hydraulic energy component, an emergency brake operation unit, a stop / emergency brake valve, and a hydraulic fuse. The probability of brake failure due to hydraulic energy failure in the present invention is 2.4E-10 / fh. Compared with the dual-redundancy aircraft brake control system, the safety and reliability of the brake system are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft brake system control, and specifically relates to a triple-redundancy brake control system. Background Art

[0002] The aircraft brake control system is an important device for aircraft braking. The reliability and safety of the brake system are directly related to the takeoff and landing safety of the aircraft, which requires the aircraft brake system to have the characteristics of high reliability and high safety.

[0003] Modern aircraft landing gears are multi-wheel systems. At present, the aircraft brake system design generally adopts the architecture of a normal brake system + an emergency brake system. The aircraft brake control system uses dual redundancy. Dual redundancy means that the normal brake system has electrical dual redundancy and hydraulic single redundancy + the emergency brake system has mechanical single redundancy. That is, the normal brake system adopts fly-by-wire control, hydraulic servo actuation, electrical dual redundancy, and hydraulic single redundancy system, and is divided into main brake control and standby brake control. The emergency brake system uses a pure mechanical structure as a backup. The disadvantage of this aircraft brake system is that once a pressure supply failure occurs in the normal brake system, only the emergency brake can be used for aircraft braking, and the probability of the brake system experiencing a Class I event of brake loss is less than 1.0E-9 / fh, and the reliability and safety of aircraft landing are relatively low. Summary of the Invention

[0004] In order to overcome the insufficient safety of using dual redundancy in the aircraft brake system, the present invention proposes a triple-redundancy aircraft brake control system.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0006] A triple-redundancy aircraft brake control system includes a normal brake system and an emergency brake system, and the normal brake system and the emergency brake system are in a parallel relationship; by default, the normal brake system implements wheel braking, and when the normal brake system fails, the emergency brake system ensures wheel braking.

[0007] The normal brake system has electrical dual redundancy and hydraulic dual redundancy, and the emergency brake system has electronic control single redundancy.

[0008] For the above triple-redundancy aircraft brake control system, the normal brake system consists of main brake control and standby brake control; the main brake control and the standby brake control are in a parallel manner. When the main brake control is in a normal situation, the main brake control implements wheel braking; when the main brake control fails, the standby brake control implements wheel braking; both the main brake control and the standby brake control have hydraulic dual redundancy.

[0009] The above-mentioned triple-redundancy aircraft brake control system, both the main brake control and the standby brake control are composed of an instruction sensor, a control module, an integrated control valve, an integrated conversion valve, a speed sensor, a conversion valve, and an energy conversion valve; each component is electrically dual-redundant, the main brake control is redundancy 1, and the standby brake control is redundancy 2;

[0010] There are 4 instruction sensors, 2 control modules, 2 integrated conversion valves, 12 speed sensors, with 1 speed sensor installed on each wheel, 12 conversion valves, with 1 conversion valve installed on each wheel, and 1 energy conversion valve.

[0011] Among the integrated control valves, there are 2 integrated control valves for the main brake control and 2 integrated control valves for the standby brake control.

[0012] The working process of the normal brake system is as follows:

[0013] At the pilot's foot pedal, the instruction sensor is installed. When braking, the instruction sensor installed under the brake pedal senses the driver's braking force, and the instruction sensor outputs an electrical signal proportional to the pedal force to the control module. The control module first turns on the cut-off valve of the integrated control valve to connect the hydraulic oil circuit, and then controls the servo valve in the integrated control valve to output brake pressure to the brake device. The magnitude of the brake pressure is proportional to the driver's operating force. At the same time, the speed sensor also sends the speed signal of the wheel to the control module, and the pressure sensor in the integrated conversion valve sends the brake pressure to the control module. The control module controls the magnitude of the current signal output to the integrated control valve through comparison and calculation, thereby controlling the brake pressure.

[0014] For the above-mentioned triple-redundancy aircraft brake control system, the normal brake system defaults to the main brake control channel for operation. If a fault occurs in the main brake control channel, the control module controls the switch to the standby control, and the main brake control and the standby brake control perform oil circuit conversion through the integrated conversion valve.

[0015] The hydraulic energy of the normal brake system is the main hydraulic system and the standby hydraulic system. The normal pressure supply system is the main hydraulic system, and the standby pressure supply system is the standby hydraulic system. The normal brake system realizes the switching between the main hydraulic system and the standby hydraulic system through the energy conversion valve.

[0016] The default pressure supply system of the normal brake system is the main hydraulic system. When a fault occurs in the main hydraulic system, the control module judges the oil source pressure fault by receiving the oil source pressure signal, issues an oil source pressure warning message, and at the same time the control energy conversion valve switches the hydraulic energy to the standby hydraulic system.

[0017] The above-mentioned triple-redundancy aircraft brake control system. The energy conversion valve receives an electrical control signal from the brake control module, converts the electrical control signal into a hydraulic-mechanical control signal, controls the conversion of hydraulic energy, and realizes the selection and switching of the pressure supply energy for the normal brake system.

[0018] The above-mentioned triple-redundancy aircraft brake control system. The control module includes a main brake control module and a standby brake control module, which are used for main brake anti-skid control and standby brake anti-skid control, and at the same time conduct fault detection and fault warning for the normal brake system; the control module implements brake control according to the brake command.

[0019] The above-mentioned triple-redundancy aircraft brake control system. The integrated control valve includes a cut-off valve, a brake servo valve, and a pressure sensor. There are 3 cut-off valves, 3 brake servo valves, and 3 pressure sensors. One cut-off valve and one brake servo valve form an independent hydraulic circuit; the cut-off valve is used to open and close the hydraulic oil circuit. The integrated control valve outputs a brake current according to the control signal output by the control module, and the pressure sensor of the integrated control valve senses the hydraulic oil circuit pressure between the cut-off valve and the brake servo valve.

[0020] The integrated conversion valve includes a conversion valve, a pressure sensor, and a hydraulic fuse. There are 3 conversion valves, 3 pressure sensors, and 3 hydraulic fuses; one conversion valve, one pressure sensor, and one hydraulic fuse form a separate branch, and the pressure conversion between the oil circuits of the main brake control and the standby brake control is realized through the conversion valve. The hydraulic fuse is installed at the outlet of the conversion valve. When the hydraulic pipeline ruptures and leaks oil, the hydraulic fuse automatically closes the oil circuit to prevent a large amount of hydraulic oil from flowing out and affecting the operation of other parts of the hydraulic system; the pressure sensor of the integrated conversion valve is used to sense the outlet pressure of the integrated conversion valve and convert the pressure value into an electric current signal and send it to the control module for pressure calibration.

[0021] The above-mentioned triple-redundancy aircraft brake control system. The emergency brake system adopts an electro-mechanical control method and consists of an accumulator, an emergency electro-hydraulic energy component, a one-way valve, an emergency brake operating unit, a stop / emergency brake valve, and a hydraulic fuse.

[0022] The emergency brake operating unit collects the driver's brake command and converts the command into an electric signal and outputs it to the stop / emergency brake valve. The stop / emergency brake valve outputs a corresponding emergency pressure or stop pressure according to the command size; a hydraulic fuse is set on the hydraulic pipeline of the emergency brake system to prevent the hydraulic pipeline from being damaged and leaking oil.

[0023] The emergency braking system is default pressurized by the main hydraulic system. When the main hydraulic power source fails, it is pressurized by the emergency electro-hydraulic power component. When the emergency electro-hydraulic power fails, it is pressurized by the accumulator. This ensures the pressurization of the hydraulic power source of the braking system under the conditions of normal braking system failure, main hydraulic system failure, and emergency electro-hydraulic power component failure, so as to ensure the implementation of the braking of the aircraft wheels.

[0024] For the above-mentioned triple-redundancy aircraft braking control system, the accumulator is of the oil-gas separation type, which is used to store hydraulic energy and provide a hydraulic source for the emergency braking system.

[0025] The emergency electro-hydraulic power component includes an oil tank and an oil pump, and the output oil pressure is 28 MPa.

[0026] The one-way valve is used to control the one-way flow of the oil in the emergency braking system. One one-way valve is provided in each of the oil inlet pipelines of the main hydraulic system and the emergency electro-hydraulic power component, which prevents the reverse flow of the oil in the emergency braking system.

[0027] The emergency braking control unit collects the emergency braking instructions of the driver, converts the emergency braking instructions into electrical signals, and at the same time outputs an emergency braking current according to the emergency braking instructions to drive the parking / emergency braking valve. The parking / emergency braking valve consists of a hydraulic solenoid valve, a direct-acting servo valve, and a parking braking valve, and is used for the servo control of the braking pressure of the main wheels.

[0028] The hydraulic solenoid valve controls the on / off of the oil inlet passage of the direct-acting servo valve. The direct-acting servo valve receives the control current output by the emergency braking control unit and outputs an emergency braking pressure proportional thereto.

[0029] The parking braking valve is of the electric control type. The parking braking valve receives the parking braking instruction signal and outputs and maintains the parking braking pressure.

[0030] The hydraulic fuse is used to automatically close the oil circuit when a fault occurs in the hydraulic pipeline of the emergency braking system, such as a rupture and oil leakage fault, to prevent a large amount of oil in the emergency braking system from flowing out and affecting the operation of other parts of the hydraulic system.

[0031] The beneficial effects of the present invention are:

[0032] A triple-redundancy aircraft braking control system, where triple-redundancy means double electrical redundancy and double hydraulic redundancy of the normal braking system + single electrical redundancy of the emergency braking system. The energy conversion valve in the normal braking system makes the hydraulic control of the normal braking system double hydraulic redundancy. Through the preliminary safety assessment of the normal braking system, compared with the current normal braking system with single hydraulic redundancy, the probability of the double-redundancy hydraulic system causing the complete failure of the normal braking system due to hydraulic power failure is 5.09E-5 / fh.

[0033] A triple-redundancy aircraft brake control system, where the emergency brake system is electrically controlled with single redundancy, i.e., the fly-by-wire control mode. Through the preliminary safety assessment of the emergency brake system, the probability of complete failure of the emergency brake system due to hydraulic energy failure is 4.72E-6 / fh.

[0034] Considering the probability of complete failure of the brake system due to hydraulic energy failure in the integrated dual-redundancy hydraulic system and the electrically controlled single-redundancy emergency brake system, the probability of brake failure of a triple-redundancy aircraft brake control system due to hydraulic energy failure is 2.4E-10 / fh, which is the probability of a Class I brake loss event. Compared with the current dual-redundancy aircraft brake control system, the safety and reliability of the brake system have been improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will be further described below in conjunction with the drawings and embodiments.

[0036] Figure 1 is the schematic diagram of the present invention;

[0037] Figure 2 is the cross-linking relationship diagram of the normal brake system components;

[0038] Figure 3 is the working schematic diagram of the energy conversion valve;

[0039] Figure 4 is the cross-linking relationship diagram of the emergency brake system components;

[0040] Figure 5 is the working schematic diagram of the stop / emergency brake valve.

[0041] In the figure: thick solid lines represent hydraulic oil circuits, and thin lines represent electrical circuits. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0042] Embodiment

[0043] A triple-redundancy aircraft brake control system adopts electrical dual-redundancy and hydraulic dual-redundancy for the normal brake system + electrically controlled single-redundancy for the emergency brake system.

[0044] A triple-redundancy aircraft brake control system includes a normal brake system and an emergency brake system, and the normal brake system and the emergency brake system are in a parallel relationship. By default, the normal brake system implements wheel braking, that is, when the normal brake system has no faults, the normal brake system ensures wheel braking; when the normal brake system fails, the emergency brake system ensures wheel braking. The principle of the triple-redundancy brake control system is as Figure 1 shown.

[0045] The normal braking system consists of a main brake control and a standby brake control. The main brake control and the standby brake control are in a parallel mode. When the main brake control is in a normal situation, the main brake control implements wheel braking; when the main brake control fails, the standby brake control implements wheel braking. Both the main brake control and the standby brake control are hydraulically dual-redundant.

[0046] Both the main brake control and the standby brake control are composed of a command sensor, a control module, an integrated control valve, an integrated switching valve, a speed sensor, a switching valve, and an energy conversion valve. Each component is electrically dual-redundant. The main brake control is redundancy 1, and the standby brake control is redundancy 2.

[0047] There are 4 command sensors, 2 control modules, 2 integrated switching valves, 12 speed sensors (1 speed sensor is set for each wheel), 12 switching valves (1 switching valve is set for each wheel), and 1 energy conversion valve.

[0048] In the integrated control valve, there are 2 integrated control valves for the main brake control and 2 integrated control valves for the standby brake control. The cross-linking relationship between each component is shown in Figure 2 .

[0049] The working process of the normal braking system is as follows:

[0050] At the pilot's foot pedal, a command sensor is installed. When braking, the command sensor installed under the brake pedal senses the driver's braking force. The command sensor outputs an electrical signal proportional to the pedal force to the control module. The control module first turns on the cut-off valve of the integrated control valve to connect the hydraulic oil circuit, and then controls the servo valve in the integrated control valve to output braking pressure to the braking device. The magnitude of the braking pressure is proportional to the driver's operating force. At the same time, the speed sensor also sends the speed signal of the wheel to the control module, and the pressure sensor in the integrated switching valve sends the braking pressure to the control module. The control module controls the magnitude of the current signal output to the integrated control valve through comparison and calculation, thereby controlling the braking pressure.

[0051] The normal braking system defaults to the main brake control channel for operation. If the main brake control channel fails, the control module controls the switch to the standby control. The main brake control and the standby brake control perform oil circuit conversion through the integrated switching valve.

[0052] The hydraulic energy of the normal braking system is the main hydraulic system and the standby hydraulic system. The normal pressure supply system is the main hydraulic system, and the standby pressure supply system is the standby hydraulic system. The normal braking system realizes the switching between the main hydraulic system and the standby hydraulic system through the energy conversion valve.

[0053] The default pressure supply system of the normal braking system is the main hydraulic system. When a fault occurs in the main hydraulic system, the control module judges the oil source pressure fault by receiving the oil source pressure signal, issues an oil source pressure warning message, and at the same time controls the energy conversion valve to switch the hydraulic energy to the standby hydraulic system.

[0054] The working principle of the energy conversion valve is as Figure 3 shown.

[0055] The energy conversion valve receives the electrical control signal from the brake control module, converts the electrical control signal into a hydraulic mechanical control signal, controls the conversion of hydraulic energy, and realizes the selection and switching of the pressure supply energy of the normal braking system.

[0056] The brake command sensor receives the driver's brake pedal force, converts the received brake pedal force into an electrical signal in proportion, and outputs the electrical signal to the brake control module.

[0057] The control module includes a main brake control module and a standby brake control module, which are used for main brake anti-skid control and standby brake anti-skid control, and at the same time detect faults and give fault warnings to the normal braking system. The control module implements brake control according to the brake command.

[0058] The integrated control valve includes a cut-off valve, a brake servo valve, and a pressure sensor. There are 3 cut-off valves, 3 brake servo valves, and 3 pressure sensors. One cut-off valve and one brake servo valve form an independent hydraulic circuit. The cut-off valve is used to open and close the hydraulic oil circuit. The integrated control valve outputs a brake current according to the control signal output by the brake control module. The pressure sensor of the integrated control valve senses the hydraulic oil circuit pressure between the cut-off valve and the brake servo valve.

[0059] The integrated conversion valve includes a conversion valve, a pressure sensor, and a hydraulic fuse. There are 3 conversion valves, 3 pressure sensors, and 3 hydraulic fuses. One conversion valve, one pressure sensor, and one hydraulic fuse form a separate branch, and the pressure conversion between the oil circuits of the main brake control and the standby brake control is realized through the conversion valve. The hydraulic fuse is installed at the outlet of the conversion valve. When the hydraulic pipeline ruptures and leaks oil, the hydraulic fuse automatically closes the oil circuit to prevent a large amount of hydraulic oil from flowing out and affecting the operation of other parts of the hydraulic system; the pressure sensor of the integrated conversion valve is used to sense the outlet pressure of the integrated conversion valve and convert the pressure value into an electric current signal and send it to the brake control module for pressure calibration.

[0060] The wheel speed sensor is used to sense the wheel speed. The wheel speed sensor collects the wheel speed signal and feeds it back to the brake control module, and the brake control module performs anti-skid control on the wheel brakes.

[0061] The transfer valve is installed on the aircraft wheel braking device and is used for the hydraulic oil circuit conversion between the normal braking system and the emergency braking system. When both the main braking control and the standby braking control of the normal braking system fail, the emergency braking system enters the braking working state to apply brakes to the wheels.

[0062] The emergency braking system adopts an electro-hydraulic control method and consists of an accumulator, an emergency electro-hydraulic energy component, a check valve, an emergency brake control unit, a parking / emergency brake valve, and a hydraulic fuse. The cross-linking relationships between the components are as Figure 4 shown.

[0063] The working process of the emergency braking system is as follows:

[0064] By default, the emergency braking system is pressurized by the main hydraulic system. When the main hydraulic energy fails, it is pressurized by the emergency electro-hydraulic energy component; when the emergency electro-hydraulic energy fails, it is pressurized by the accumulator. This ensures the supply of hydraulic energy for the braking system under the conditions of normal braking system failure, main hydraulic system failure, and emergency electro-hydraulic energy component failure, so as to ensure the implementation of aircraft wheel braking.

[0065] The emergency brake control unit collects the pilot's brake command and converts it into an electrical signal for output to the parking / emergency brake valve. The parking / emergency brake valve outputs the corresponding emergency pressure or parking pressure according to the command size. A hydraulic fuse is set on the hydraulic pipeline of the emergency braking system to prevent oil leakage due to hydraulic pipeline breakage.

[0066] The accumulator is of the oil-gas separation type and is used to store hydraulic energy and provide a hydraulic source for the emergency braking system.

[0067] The emergency electro-hydraulic energy component includes an oil tank and an oil pump, and the output oil pressure is 28 MPa.

[0068] The check valve is used to control the one-way flow of the oil in the emergency braking system. A check valve is set on each of the inlet pipelines of the main hydraulic system and the emergency electro-hydraulic energy component to prevent the reverse flow of the oil in the emergency braking system.

[0069] The emergency brake control unit collects the pilot's emergency brake command, converts the emergency brake command into an electrical signal, and at the same time outputs an emergency brake current according to the emergency brake command to drive the parking / emergency brake valve.

[0070] The parking / emergency brake valve consists of a hydraulic solenoid valve, a direct-acting servo valve, and a parking brake valve, and is used for the servo control of the main wheel braking pressure. The working principle of the parking / emergency brake valve is as Figure 5 shown.

[0071] The hydraulic solenoid valve controls the on / off of the oil inlet circuit of the direct-acting servo valve. The direct-acting servo valve receives the control current output by the emergency brake control unit and outputs an emergency brake pressure proportional to it.

[0072] The shutdown brake valve is electrically controlled. The shutdown brake valve receives the shutdown brake command signal and outputs and maintains the shutdown brake pressure.

[0073] The hydraulic fuse is used to automatically close the oil circuit when a failure occurs in the hydraulic pipeline of the emergency braking system, such as a rupture and oil leakage failure, to prevent a large amount of oil in the emergency braking system from being lost and affecting the operation of other parts of the hydraulic system.

Claims

1. A triple-redundancy aircraft brake control system, characterized in that, it includes a normal brake system and an emergency brake system, and the normal brake system and the emergency brake system are in a parallel relationship; by default, the normal brake system implements wheel braking, and when the normal brake system fails, the emergency brake system ensures wheel braking; the normal brake system is electrically dual-redundant and hydraulically dual-redundant, and the emergency brake system is electrically controlled single-redundant; the normal brake system consists of a main brake control and a standby brake control; both the main brake control and the standby brake control are hydraulically dual-redundant; both the main brake control and the standby brake control are composed of a command sensor, a control module, an integrated control valve, an integrated conversion valve, a speed sensor, a conversion valve, and an energy conversion valve; each component is electrically dual-redundant; the emergency brake system adopts an electro-mechanical control method and consists of an accumulator, an emergency electro-hydraulic energy component, a one-way valve, an emergency brake operation unit, a shutdown / emergency brake valve, and a hydraulic fuse.

2. The triple-redundancy aircraft brake control system according to claim 1, characterized in that, the main brake control and the standby brake control are in a parallel manner. When the main brake control is in a normal situation, the main brake control implements wheel braking; when the main brake control fails, the standby brake control implements wheel braking.

3. The triple-redundancy aircraft brake control system according to claim 2, characterized in that, the main brake control is redundancy 1, and the standby brake control is redundancy 2; there are 4 command sensors, 2 control modules, 2 integrated conversion valves, 12 speed sensors, with 1 speed sensor set for each wheel, 12 conversion valves, with 1 conversion valve set for each wheel, and 1 energy conversion valve; among the integrated control valves, there are 2 integrated control valves for the main brake control and 2 integrated control valves for the standby brake control; The working process of the normal brake system is as follows: At the pilot's foot pedal, the command sensor is installed. When braking, the command sensor installed under the brake pedal senses the driver's braking force, and the command sensor outputs an electrical signal proportional to the pedal force to the control module. The control module first turns on the cut-off valve of the integrated control valve to connect the hydraulic oil circuit, and then controls the servo valve in the integrated control valve to output braking pressure to the braking device. The magnitude of the braking pressure is proportional to the driver's operating force. At the same time, the speed sensor also sends the speed signal of the wheel to the control module, and the pressure sensor in the integrated conversion valve sends the braking pressure to the control module. The control module controls the magnitude of the current signal output to the integrated control valve through comparison and calculation, thereby controlling the braking pressure.

4. The triple-redundancy aircraft brake control system according to claim 3, characterized in that, the normal brake system defaults to the main brake control channel for operation. If the main brake control channel fails, the control module controls the switch to the standby control, and the main brake control and the standby brake control perform oil circuit conversion through the integrated conversion valve; The normal braking system uses the main hydraulic system and the standby hydraulic system as the hydraulic energy sources. The normal pressure supply system is the main hydraulic system, and the standby pressure supply system is the standby hydraulic system. The normal braking system realizes the switching between the main hydraulic system and the standby hydraulic system through the energy conversion valve. The default pressure supply system of the normal braking system is the main hydraulic system. When a fault occurs in the main hydraulic system, the control module judges the oil source pressure fault by receiving the oil source pressure signal, issues an oil source pressure alarm message, and at the same time, the energy conversion valve switches the hydraulic energy to the standby hydraulic system.

5. The triple-redundancy aircraft braking control system according to claim 3, characterized in that, The energy conversion valve receives an electrical control signal from the control module, converts the electrical control signal into a hydraulic-mechanical control signal, controls the conversion of hydraulic energy, and realizes the selection and switching of the pressure supply energy of the normal braking system.

6. The triple-redundancy aircraft braking control system according to claim 3, characterized in that, The control module includes a main braking control module and a standby braking control module, which are used for main braking anti-skid control and standby braking anti-skid control, and at the same time detect faults and issue fault alarms for the normal braking system; the control module implements braking control according to the braking command.

7. The triple-redundancy aircraft braking control system according to claim 3, characterized in that, The integrated control valve includes a cut-off valve, a brake servo valve, and a pressure sensor. There are 3 cut-off valves, 3 brake servo valves, and 3 pressure sensors. One cut-off valve and one brake servo valve form an independent hydraulic path; the cut-off valve is used to open and close the hydraulic oil circuit. The integrated control valve outputs a braking current according to the control signal output by the control module. The pressure sensor of the integrated control valve senses the hydraulic oil circuit pressure between the cut-off valve and the brake servo valve. The integrated conversion valve includes a conversion valve, a pressure sensor, and a hydraulic fuse. There are 3 conversion valves, 3 pressure sensors, and 3 hydraulic fuses; one conversion valve, one pressure sensor, and one hydraulic fuse form a separate branch, and the pressure conversion between the oil circuits of the main braking control and the standby braking control is realized through the conversion valve; the hydraulic fuse is installed at the outlet of the conversion valve. When the hydraulic pipeline ruptures and leaks oil, the hydraulic fuse automatically closes the oil circuit to prevent a large amount of hydraulic oil from flowing out and affecting the operation of other parts of the hydraulic system; the pressure sensor of the integrated conversion valve is used to sense the outlet pressure of the integrated conversion valve and convert the pressure value into an electrical signal and send it to the control module for pressure calibration.

8. The triple-redundancy aircraft braking control system according to claim 1, characterized in that, The emergency braking operation unit collects the driver's braking command and converts the command into an electrical signal and outputs it to the shutdown / emergency braking valve. The shutdown / emergency braking valve outputs the corresponding emergency pressure or shutdown pressure according to the command size; a hydraulic fuse is set on the hydraulic pipeline of the emergency braking system to prevent the hydraulic pipeline from being damaged and leaking oil. The emergency braking system is default pressurized by the main hydraulic system. When the main hydraulic energy fails, it is pressurized by the emergency electro-hydraulic energy component; when the emergency electro-hydraulic energy fails, it is pressurized by the accumulator. Thus, it ensures the pressurization of the hydraulic energy of the braking system under the conditions of normal braking system failure, main hydraulic system failure, and emergency electro-hydraulic energy component failure to guarantee the implementation of the braking of the aircraft wheels. A check valve is provided in each of the oil inlet pipelines of the main hydraulic system and the emergency electro-hydraulic energy component to control the one-way flow of the oil in the emergency braking system.

9. The triple-redundancy aircraft braking control system according to claim 8, characterized in that the accumulator is of the oil-gas separation type, used to store hydraulic energy and provide a hydraulic source for the emergency braking system; the emergency electro-hydraulic energy component includes an oil tank and an oil pump, and the output oil pressure is 28 MPa; the check valve is used to control the one-way flow of the oil in the emergency braking system. A check valve is provided in each of the oil inlet pipelines of the main hydraulic system and the emergency electro-hydraulic energy component to prevent the reverse flow of the oil in the emergency braking system; the emergency braking control unit collects the emergency braking command of the driver, converts the emergency braking command into an electrical signal, and at the same time outputs an emergency braking current according to the emergency braking command to drive the stop / emergency braking valve; the stop / emergency braking valve consists of a hydraulic solenoid valve, a direct-acting servo valve, and a stop braking valve, and is used for the servo control of the braking pressure of the main wheels; the hydraulic solenoid valve controls the on / off of the oil inlet circuit of the direct-acting servo valve. The direct-acting servo valve receives the control current output by the emergency braking control unit and outputs an emergency braking pressure proportional thereto; the stop braking valve is of an electric control mode. The stop braking valve receives the stop braking command signal and outputs and maintains the stop braking pressure; the hydraulic fuse is used to automatically close the oil circuit when a fault occurs in the hydraulic pipeline of the emergency braking system, such as a rupture and oil leakage fault, to prevent a large amount of oil in the emergency braking system from flowing out and affecting the operation of other parts of the hydraulic system.

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