Aircraft bleed air system pressure regulating system and control method thereof

Abstract

The invention belongs to the technical field of aviation aircraft bleed air systems, and discloses an aircraft bleed air system pressure adjusting system and a control method thereof.The system comprises an upper computer, a controller, a torque motor, a pipeline pressure sensor and a shut-off valve butterfly valve, the upper computer is in signal connection with the controller, and the controller is in signal connection with the torque motor; the torque motor is connected with the shut-off valve butterfly valve and controls the angle of the shut-off valve butterfly valve, the shut-off valve butterfly valve is arranged in an air entraining pipeline of the aircraft air entraining system, and the pipeline pressure sensor is arranged in the air entraining pipeline of the aircraft air entraining system; the upper computer sends pressure instruction data to the controller, and the controller controls the torque motor to adjust the angle of the butterfly valve of the pressure adjusting shut-off valve, so that the bleed pressure of the air bleed system of the airplane is within the pressure instruction range. By controlling the angle of the valve clack of the pressure regulation shut-off valve, the pressure regulation structure of the valve is simplified, the weight of a valve product is reduced, the reliability of the valve product is improved, and the service life of the valve product is prolonged.

Description

Technical Field

[0001] This invention belongs to the technical field of aircraft bleed air systems, and relates to a pressure regulation system for an aircraft bleed air system, specifically to a pressure regulation system and control method for an aircraft bleed air system. Background Technology

[0002] The aircraft bleed air system is a crucial functional subsystem of the aircraft's environmental control system. Its function is to cool and depressurize the high-temperature, high-pressure air drawn from the aircraft engine / APU, and then supply the air to downstream user systems at the appropriate temperature and pressure. Bleed air pressure regulation is the core function of the bleed air system. During bleed air pressure regulation, the aircraft adjusts the high-pressure air drawn from the engine to the pressure required by the downstream air-consuming systems through a pressure regulating shut-off valve.

[0003] The pressure regulating shut-off valve, under the control of the control system, regulates the air supply pressure. Traditional bleed air systems primarily achieve target pressure control through the mechanical structure of the pressure regulating shut-off valve itself; this valve is referred to as the "absolute pressure regulating valve." The control system simply controls the valve's opening and closing. After the valve opens, the interaction between the bleed air pressure in the control chamber and the spring force maintains the downstream pressure at the set value. This structure is relatively complex due to the addition of components such as the downstream pressure guiding device, leading to increased product weight and decreased reliability. Furthermore, the same model of absolute pressure regulating valve, after factory calibration, can only output a fixed pressure, failing to meet the varying bleed air pressure output requirements of different engine models and under different bleed air conditions. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides an aircraft bleed air system pressure regulation system and its control method, which can control the pressure regulation shut-off valve of the aircraft bleed air system, thereby stabilizing the downstream pressure at 342 kPaA ± 10 kPaA.

[0005] The technical solution of the present invention is as follows: A pressure regulation system for an aircraft bleed air system includes a host computer, a controller, a torque motor, a pipeline pressure sensor, and a shut-off butterfly valve. The host computer is connected to the controller via a signal, and the controller is connected to the torque motor via a signal. The torque motor is connected to and controls the angle of the shut-off butterfly valve. The shut-off butterfly valve is located inside the bleed air pipeline of the aircraft bleed air system. The pipeline pressure sensor is located inside the bleed air pipeline of the aircraft bleed air system. The host computer sends pressure command data to the controller, and the controller controls the torque motor to adjust the angle of the pressure regulation shut-off butterfly valve, so that the bleed air pressure of the aircraft bleed air system is within the pressure command range.

[0006] Furthermore, a torque motor is connected to and controls the spray valve. The rear end of the spray valve is a pneumatic actuator, which drives the shut-off butterfly valve to move through its internal piston structure.

[0007] Furthermore, a pipeline pressure sensor is installed at the rear end of the shut-off butterfly valve. The pipeline pressure sensor collects pressure signals and sends them to the controller. The controller dynamically adjusts the pressure according to the pressure signal to regulate the angle of the shut-off butterfly valve.

[0008] Furthermore, the controller includes an MCU, an FPGA, a drive circuit, and an AD conversion circuit. The MCU communicates with the host computer and receives pressure command data sent by the host computer. The MCU has a built-in embedded polling software system that calculates the difference between the set target pressure value and the feedback pressure value. At the same time, it combines the closed-loop control coefficients Kp, Ki, and Kd to calculate the current command for the current control cycle and sends it to the FPGA. The FPGA generates a control current command and sends it to the drive circuit. The drive circuit generates a PWM signal to control the torque motor.

[0009] Furthermore, the pressure signal collected by the pipeline pressure sensor is converted from analog to digital by the AD conversion circuit and then sent to the FPGA. The FPGA generates a control current command based on the difference between the pressure signal collected by the pipeline pressure sensor and the pressure command data sent by the MCU.

[0010] A control method for an aircraft bleed air system pressure regulation system, using the aforementioned aircraft bleed air system pressure regulation system, includes the following steps: Step 1: Set the target control pressure in the host computer; Step 2: Obtain the feedback pressure collected by the pipeline pressure sensor. Step 3: Obtain the control current command for the torque motor based on the difference between the target control pressure and the feedback pressure; Step four: Convert the obtained current command into a drive current signal to drive the torque motor of the pressure regulating shut-off valve, dynamically adjust the angle of the pressure regulating shut-off valve butterfly valve, and realize dynamic closed-loop control of pressure.

[0011] Furthermore, the current command is calculated as follows: E(K) = P1 - P2(K); INT(K) = Ki * Ts * E(K); If INT(K) > 0.2, then INT(K) = 0.2; if INT(K) < -0.2, then INT(K) = -0.2; otherwise, INT(K) = INT(K). C(K)=C(K-1)+Kp*(E(K)-E(K-1))+INT(K)+Kd*(E(K)-2*E(K-1)+E(K-2)) / Ts; If C(K) > 50, then C(K) = 50; if C(K) < 0, then C(K) = 0; otherwise, C(K) = C(K). E(K) represents the pressure difference value of the current control cycle, E(K-1) represents the pressure difference value of the previous control cycle, E(K-2) represents the pressure difference value of the control cycle before that, P2(K) represents the pressure feedback value of the current control cycle, INT(K) represents the integral term calculation value of the current control cycle, C(K) represents the current command output of the current control cycle, C(K-1) represents the current command output of the previous control cycle, and Ts represents the control cycle.

[0012] Furthermore, the CodeWarrior integrated development environment is installed on the host computer, and the compiler and driver corresponding to the MCU that matches the controller are configured. The host computer and the controller are connected through the JTAG interface, and the hardware communication is ensured to be normal. The target pressure value is set to P1 in the main program file of the host computer using C / C++ language. After being compiled by the compiler, the program is downloaded to the MCU that matches the controller through the JTAG interface.

[0013] The beneficial effects of this invention are as follows: 1. This invention simplifies the valve's own pressure regulating structure, reduces the weight of the valve product, and improves the reliability and service life of the valve product by controlling the valve disc angle of the pressure regulating shut-off valve.

[0014] 2. This invention adjusts the output pressure after the valve through program software, which can make the same type of valve output different pressures according to the needs, thus expanding the application scenarios of the valve, avoiding the disadvantage that the same valve can only output a certain fixed pressure, and promoting the serialization of subsequent valve products.

[0015] 3. This invention only requires collecting the valve outlet pressure P, and controlling the valve drive current gain by controlling the pressure magnitude. The control is simple and easy to implement.

[0016] 4. This invention adopts the traditional incremental PID control algorithm, which is widely used, robust, and has low resource consumption. It is very suitable for scenarios with limited computing resources, such as airborne embedded systems and microcontrollers, and the control accuracy can meet the requirements of airborne equipment for bleed air flow control. Attached Figure Description

[0017] Figure 1 This is a block diagram illustrating the control principle of the pressure regulating object of the present invention.

[0018] Figure 2 This is a hardware block diagram of the control system of the present invention.

[0019] Figure 3 This is a block diagram illustrating the control algorithm principle of this invention.

[0020] Figure 4 This is a block diagram illustrating the actual control effect of the present invention.

[0021] Among them, 1 is the control system, 2 is the spray valve, 3 is the pneumatic actuator, and 4 is the simplified butterfly valve. Detailed Implementation

[0022] This section describes embodiments of the present invention, used to explain and illustrate the technical solutions of the present invention. Unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0023] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating directions or positional relationships, are based on the orientation or positional relationships in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or case referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include more than one of those features. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0024] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integrated connections; they can refer to mechanical connections or point connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0025] Example 1: A control method that drives a pressure regulating valve will simplify product structure and reduce product weight. Furthermore, by simply adjusting the downstream pressure setpoint in the control program via software, target pressure regulation can be achieved, avoiding the need for rework and adjustment of the control spring during each pressure calibration. This will facilitate the standardization and serialization of valve products. The application of this control method can effectively reduce the weight of the pressure regulating shut-off valve and improve valve reliability.

[0026] A pressure regulation system for an aircraft bleed air system includes a host computer, a controller, a torque motor, a pipeline pressure sensor, and a shut-off butterfly valve. The host computer is connected to the controller via a signal, and the controller is connected to the torque motor via a signal. The torque motor is connected to and controls the angle of the shut-off butterfly valve. The shut-off butterfly valve is located inside the bleed air pipeline of the aircraft bleed air system. The pipeline pressure sensor is located inside the bleed air pipeline of the aircraft bleed air system. The host computer sends pressure command data to the controller, and the controller controls the torque motor to adjust the angle of the pressure regulation shut-off butterfly valve, so that the bleed air pressure of the aircraft bleed air system is within the pressure command range.

[0027] A torque motor connects to and controls the spray valve. The rear end of the spray valve is a pneumatic actuator, which drives the shut-off butterfly valve to move through its internal piston structure.

[0028] The pipeline pressure sensor is located at the rear end of the shut-off butterfly valve. The pipeline pressure sensor collects pressure signals and sends them to the controller. The controller dynamically adjusts the pressure according to the pressure signals to regulate the angle of the shut-off butterfly valve.

[0029] The controller includes an MCU, an FPGA, a drive circuit, and an AD conversion circuit. The MCU communicates with the host computer and receives pressure command data sent by the host computer. The MCU has a built-in embedded polling software system that calculates the difference between the set target pressure value and the feedback pressure value. At the same time, it combines the closed-loop control coefficients Kp, Ki, and Kd to calculate the current command for the current control cycle and sends it to the FPGA. The FPGA generates a control current command and sends it to the drive circuit. The drive circuit generates a PWM signal to control the torque motor.

[0030] The pressure signal collected by the pipeline pressure sensor is converted from analog to digital by the AD conversion circuit and then sent to the FPGA. The FPGA generates a control current command based on the difference between the pressure signal collected by the pipeline pressure sensor and the pressure command data sent by the MCU.

[0031] A control method for an aircraft bleed air system pressure regulation system, using the aforementioned aircraft bleed air system pressure regulation system, includes the following steps: Step 1: Set the target control pressure in the host computer; Step 2: Obtain the feedback pressure collected by the pipeline pressure sensor. Step 3: Obtain the control current command for the torque motor based on the difference between the target control pressure and the feedback pressure; Step four: Convert the obtained current command into a drive current signal to drive the torque motor of the pressure regulating shut-off valve, dynamically adjust the angle of the pressure regulating shut-off valve butterfly valve, and realize dynamic closed-loop control of pressure.

[0032] The current command is calculated as follows: E(K) = P1 - P2(K); INT(K) = Ki * Ts * E(K); If INT(K) > 0.2, then INT(K) = 0.2; if INT(K) < -0.2, then INT(K) = -0.2; otherwise, INT(K) = INT(K). C(K)=C(K-1)+Kp*(E(K)-E(K-1))+INT(K)+Kd*(E(K)-2*E(K-1)+E(K-2)) / Ts; If C(K) > 50, then C(K) = 50; if C(K) < 0, then C(K) = 0; otherwise, C(K) = C(K). E(K) represents the pressure difference value of the current control cycle, E(K-1) represents the pressure difference value of the previous control cycle, E(K-2) represents the pressure difference value of the control cycle before that, P2(K) represents the pressure feedback value of the current control cycle, INT(K) represents the integral term calculation value of the current control cycle, C(K) represents the current command output of the current control cycle, C(K-1) represents the current command output of the previous control cycle, and Ts represents the control cycle.

[0033] Install the CodeWarrior integrated development environment on the host computer, configure the compiler and driver corresponding to the MCU that matches the controller, connect the host computer and the controller through the JTAG interface, and ensure that the hardware communication is normal; set the target pressure value to P1 in the main program file of the host computer using C / C++ language, compile it with the compiler, and then download the program to the MCU that matches the controller through the JTAG interface.

[0034] Example 2: An aircraft bleed air system pressure regulation system includes a host computer, a controller, a torque motor, and a pipeline pressure sensor. After a pressure command is input into the host computer, the host computer sends pressure command data to the controller. The controller controls the torque motor to adjust the angle of the pressure regulating shut-off valve butterfly valve, so that the bleed air pressure of the aircraft bleed air system is within the pressure command range. The pipeline pressure sensor is installed in the bleed air pipeline downstream of the pressure regulating shut-off valve butterfly valve of the aircraft bleed air system. The pipeline pressure sensor collects pressure signals and sends them to the controller. The controller dynamically adjusts the angle of the pressure regulating shut-off valve butterfly valve according to the pressure signals.

[0035] like Figure 1 As shown: When the system performs pressure control, it inputs different current values ​​to the nozzle valve (2) through the control system to adjust the outlet gas pressure of the nozzle. The gas pressure difference is converted into an actuating force to drive the piston to reciprocate through the pneumatic actuator (3). Then, the gas pressure in the pipeline is controlled by the rotation of the butterfly plate of the butterfly valve (4). The matching of the butterfly valve outlet pressure and the target pressure is achieved through the control algorithm.

[0036] The control method adopted by the system includes the following steps: Step 1: Set target control pressure.

[0037] exist Figure 2 The host computer is equipped with the CodeWarrior integrated development environment, and the compiler and driver corresponding to the MCU that is compatible with the controller are configured. The host computer is connected to the controller through the JTAG interface, and the hardware communication is ensured to be normal. The target pressure value is set to P1 using C / C++ language in the main program file. After compilation, the program is downloaded to the MCU that is matched with the controller via the JTAG interface.

[0038] Step 2: Obtain the pressure value collected by the pipeline pressure sensor.

[0039] The pipeline pressure sensor outputs an analog signal of 0.5V to 4.5V. Figure 2 The controller's internal AD conversion circuit converts the signal into a digital signal and inputs it into the controller's internal FPGA. The FPGA then calculates the feedback pressure value and transmits it to the MCU via the data bus between the FPGA and the MCU as the pressure feedback signal P2.

[0040] Step 3: Obtain the control current command based on the difference between the target pressure and the feedback pressure.

[0041] The MCU obtains the difference between the current target pressure and the feedback pressure to get the pressure difference value of the current control cycle. At the same time, it calculates the current command of the current control cycle by combining the closed-loop control coefficients Kp, Ki, and Kd, and transmits it to the FPGA through the data bus. The current command calculation uses an incremental PID control method; the algorithm block diagram is shown below. Figure 3 ; The formula for calculating the current command is as follows: E(K) = P1 - P2(K); INT(K) = Ki * Ts * E(K); If INT(K) > 0.2, then INT(K) = 0.2; if INT(K) < -0.2, then INT(K) = -0.2; otherwise, INT(K) = INT(K). C(K)=C(K-1)+Kp*(E(K)-E(K-1))+INT(K)+Kd*(E(K)-2*E(K-1)+E(K-2)) / Ts; If C(K) > 50, then C(K) = 50; if C(K) < 0, then C(K) = 0; otherwise, C(K) = C(K). E(K) represents the pressure difference value of the current control cycle, E(K-1) represents the pressure difference value of the previous control cycle, E(K-2) represents the pressure difference value of the control cycle before that, P2(K) represents the pressure feedback value of the current control cycle, INT(K) represents the integral term calculation value of the current control cycle, C(K) represents the current command output of the current control cycle, C(K-1) represents the current command output of the previous control cycle, and Ts represents the control cycle.

[0042] Step 4: Convert the obtained current command into a drive current signal to drive the torque motor of the pressure regulating shut-off valve, dynamically adjust the angle of the pressure regulating shut-off valve disc valve, and achieve the purpose of dynamic closed-loop pressure control.

[0043] The FPGA receives the current command sent by the MCU and converts it into a variable duty cycle PWM drive current signal through the drive circuit. This signal drives the torque motor of the pressure regulating shut-off valve, thereby dynamically adjusting the output angle of the pressure regulating shut-off valve butterfly valve to achieve the purpose of dynamic closed-loop pressure control.

[0044] Figure 4 The control effect of the present invention in a laboratory environment is demonstrated.

[0045] Figure 4 The horizontal axis represents time, in seconds; it contains two vertical axes, with output pressure in kPaA; and the pressure regulating shut-off valve controls the current in mA. Figure 4 In the diagram, the blue curve represents the pressure change curve of the pipeline downstream of the pressure regulating shut-off valve, and the red curve represents the current command change curve. Figure 4 The test shown in the figure had a target pressure set at 342 kPaA ± 10 kPaA; from Figure 4 It can be seen that when the bleed air state changes, the control method described in this invention can quickly adjust the downstream pressure to the target pressure range of 342 kPaA ± 10 kPaA, and the adjustment time does not exceed 40 seconds, which can meet the requirements of airborne systems for pressure adjustment time and steady-state accuracy. Furthermore, disturbance factors are incorporated into the adjustment process, such as... Figure 4 As shown, the stability and availability of the control method were tested.

[0046] The above description is merely illustrative of the technical solutions of this invention. Those skilled in the art can modify or make equivalent substitutions to the technical solutions of this invention. All modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A pressure regulation system for an aircraft bleed air system, characterized in that, The system includes a host computer, a controller, a torque motor, a pipeline pressure sensor, and a shut-off butterfly valve. The host computer is connected to the controller via a signal, and the controller is connected to the torque motor via a signal. The torque motor is connected to and controls the angle of the shut-off butterfly valve. The shut-off butterfly valve is located inside the bleed air duct of the aircraft bleed air system. The pipeline pressure sensor is also located inside the bleed air duct of the aircraft bleed air system. The host computer sends pressure command data to the controller, and the controller controls the torque motor to adjust the angle of the pressure regulating shut-off butterfly valve, so that the bleed air pressure of the aircraft bleed air system is within the pressure command range.

2. The pressure regulation system for an aircraft bleed air system according to claim 1, characterized in that, A torque motor connects to and controls the spray valve. The rear end of the spray valve is a pneumatic actuator, which drives the shut-off butterfly valve to move through its internal piston structure.

3. The pressure regulation system for an aircraft bleed air system according to claim 1, characterized in that, The pipeline pressure sensor is located at the rear end of the shut-off butterfly valve. The pipeline pressure sensor collects pressure signals and sends them to the controller. The controller dynamically adjusts the pressure according to the pressure signals to regulate the angle of the shut-off butterfly valve.

4. The pressure regulation system for an aircraft bleed air system according to claim 1, characterized in that, The controller includes an MCU, an FPGA, a drive circuit, and an AD conversion circuit. The MCU communicates with the host computer and receives pressure command data sent by the host computer. The MCU has a built-in embedded polling software system that calculates the difference between the set target pressure value and the feedback pressure value. At the same time, it combines the closed-loop control coefficients Kp, Ki, and Kd to calculate the current command for the current control cycle and sends it to the FPGA. The FPGA generates a control current command and sends it to the drive circuit. The drive circuit generates a PWM signal to control the torque motor.

5. The pressure regulation system for an aircraft bleed air system according to claim 4, characterized in that, The pressure signal collected by the pipeline pressure sensor is converted from analog to digital by the AD conversion circuit and then sent to the FPGA. The FPGA generates a control current command based on the difference between the pressure signal collected by the pipeline pressure sensor and the pressure command data sent by the MCU.

6. A control method for an aircraft bleed air system pressure regulation system, using the aircraft bleed air system pressure regulation system as described in claim 1, characterized in that, Includes the following steps: Step 1: Set the target control pressure in the host computer; Step 2: Obtain the feedback pressure collected by the pipeline pressure sensor. Step 3: Obtain the control current command for the torque motor based on the difference between the target control pressure and the feedback pressure; Step four: Convert the obtained current command into a drive current signal to drive the torque motor of the pressure regulating shut-off valve, dynamically adjust the angle of the pressure regulating shut-off valve butterfly valve, and realize dynamic closed-loop control of pressure.

7. The control method for an aircraft bleed air system pressure regulation system according to claim 6, characterized in that, The current command is calculated as follows: E(K) = P1 - P2(K); INT(K) = Ki * Ts * E(K); If INT(K) > 0.2, then INT(K) = 0.2; if INT(K) < -0.2, then INT(K) = -0.2; otherwise, INT(K) = INT(K). C(K)=C(K-1)+Kp*(E(K)-E(K-1))+INT(K)+Kd*(E(K)-2*E(K-1)+E(K-2)) / Ts; If C(K) > 50, then C(K) = 50; if C(K) < 0, then C(K) = 0; otherwise, C(K) = C(K). E(K) represents the pressure difference value of the current control cycle, E(K-1) represents the pressure difference value of the previous control cycle, E(K-2) represents the pressure difference value of the control cycle before that, P2(K) represents the pressure feedback value of the current control cycle, INT(K) represents the integral term calculation value of the current control cycle, C(K) represents the current command output of the current control cycle, C(K-1) represents the current command output of the previous control cycle, and Ts represents the control cycle.

8. The control method for an aircraft bleed air system pressure regulation system according to claim 6, characterized in that, Install the CodeWarrior integrated development environment on the host computer, configure the compiler and driver corresponding to the MCU that matches the controller, connect the host computer and the controller through the JTAG interface, and ensure that the hardware communication is normal; set the target pressure value to P1 in the main program file of the host computer using C / C++ language, compile it with the compiler, and then download the program to the MCU that matches the controller through the JTAG interface.

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