Aerospace aviation fuel pump operation state monitoring circuit based on micro-processing monitoring chip

Abstract

The application provides a spaceflight and aviation fuel pump operation state monitoring circuit based on a micro-processing monitoring chip, and relates to the technical field of spaceflight and aviation fuel pumps.The device comprises a micro-processing monitoring circuit, a brushless direct current motor Hall sensor, a power input circuit and a drive control logic circuit; the micro-processing monitoring circuit is connected with the brushless direct current motor Hall sensor, the power input circuit and the drive control logic circuit respectively, and the brushless direct current motor Hall sensor is connected with the drive control logic circuit.The application simplifies the brushless direct current motor operation monitoring hardware circuit of the spaceflight and aviation pure hardware driver fuel pump.

Description

TECHNICAL FIELD

[0001] The present specification relates to the technical field of aerospace fuel pump, and particularly relates to a running state monitoring circuit of aerospace fuel pump based on a micro-processing monitoring chip. BACKGROUND

[0002] In the field of aerospace, the stable operation of the fuel pump and the fuel pump is directly related to the safety and performance of the aircraft. At present, the motor control system of the aerospace low-pressure fuel pump usually adopts hardware IC chip or gate circuit to build logic control, and does not involve software code control. In the field of motor control of aerospace fuel pump, commonly used special hardware logic motor control chips such as MC33035 and UC3625 can realize basic motor driving control, such as providing suitable controller logic and overcurrent protection for the motor to ensure that the motor operates at a certain speed and direction. However, there are obvious shortcomings in the motor running state monitoring. From the real-time point of view, when the motor appears abnormal stop or abnormal change of speed or abnormal input of power supply, these chips cannot capture these signals, which leads to the failure to discover and handle the fault in time, and poses a potential threat to the safe and stable operation of the aerospace equipment. In the monitoring mode, the traditional scheme often relies on software algorithm and additional hardware circuit. The software algorithm not only increases the development cost and time, but also may fail due to software vulnerabilities, compatibility problems or space radiation interference, resulting in monitoring failure. The additional hardware circuit not only increases the system size and weight, which is contrary to the strict requirements of aerospace equipment for lightweight, miniaturization and low cost, but also increases the system cost. SUMMARY

[0003] In view of the above shortcomings in the prior art, the running state monitoring circuit of aerospace fuel pump based on the micro-processing monitoring chip simplifies the brushless direct current motor running monitoring hardware circuit of the aerospace pure hardware driver fuel pump.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows: a running state monitoring circuit of aerospace fuel pump based on a micro-processing monitoring chip, comprising:

[0005] The micro-processing monitoring circuit, the brushless direct current motor Hall sensor, the power input circuit and the driving control logic circuit are connected respectively, and the brushless direct current motor Hall sensor is connected with the driving control logic circuit.

[0006] Further, the micro-processing monitoring circuit comprises:

[0007] The chip U2, the resistor R2, the resistor R4, the resistor R6, the resistor R27, the voltage stabilizing diode V5 and the grounding capacitor C1; wherein the first pin of the chip U2 is connected with one end of the resistor R2, the second pin of the chip U2 is connected with one end of the resistor R27, the output end of the voltage stabilizing diode V5 and the grounding capacitor C1 respectively, the other end of the resistor R27 is connected with the 15V voltage terminal, the third pin of the chip U2 and the input end of the voltage stabilizing diode V5 are grounded, the fourth pin of the chip U2 is connected with the power input circuit, the fifth pin of the chip U2 is connected with the driving control logic circuit, the sixth pin of the chip U2 is connected with one end of the resistor R6, the other end of the resistor R6 is connected with the brushless direct current motor Hall sensor, the seventh pin of the chip U2 is connected with one end of the resistor R4, the other end of the resistor R4 is connected with the driving control logic circuit, and the eighth pin of the chip U2 is connected with the other end of the resistor R2.

[0008] Further, the brushless direct current motor Hall sensor comprises:

[0009] The motor Hall plate P1, the resistor R23, the resistor R24, the resistor R25, the grounding capacitor C18, the grounding capacitor C20 and the grounding capacitor C22; wherein the first pin of the motor Hall plate P1 is connected with the 15V voltage terminal, the second pin of the motor Hall plate P1 is grounded, the third pin of the motor Hall plate P1 is connected with one end of the resistor R23 and the other end of the resistor R6 respectively, the fourth pin of the motor Hall plate P1 is connected with one end of the resistor R24, the fifth pin of the motor Hall plate P1 is connected with one end of the resistor R25, the other end of the resistor R23 and the grounding capacitor C18 are connected with the driving control logic circuit respectively, the other end of the resistor R24 and the grounding capacitor C20 are connected with the driving control logic circuit respectively, and the other end of the resistor R25 and the grounding capacitor C22 are connected with the driving control logic circuit respectively.

[0010] Further, the power input circuit comprises:

[0011] The resistor R1, the resistor R3, the resistor R5, the capacitor C2, the capacitor C3, the capacitor C4, the capacitor C5, the TVS tube V2 and the chip U1; wherein one end of the resistor R1 is connected with the 28V input terminal, the other end of the resistor R1 is connected with one end of the resistor R3, one end of the capacitor C2, the first pin of the chip U1 and one end of the TVS tube V2 respectively, the other end of the resistor R3 is connected with the grounding resistor R5, the grounding capacitor C5 and the fourth pin of the chip U2 respectively, the other end of the TVS tube V2, the other end of the capacitor C2, the third pin of the chip U1, the negative pole of the polarity capacitor C4 and one end of the capacitor C3 are grounded, the second pin of the chip U1, the positive pole of the polarity capacitor C4 and the other end of the capacitor C3 are connected with the 15V voltage terminal.

[0012] Further, the driving control logic circuit comprises:

[0013] The resistance R7, the resistance R8, the resistance R10, the resistance R11, the resistance R12, the resistance R14, the resistance R15, the resistance R16, the resistance R17, the resistance R19, the resistance R21, the resistance R22, the triode V3, the capacitor C6, the capacitor C8, the capacitor C9, the capacitor C10, the capacitor C11, the capacitor C12, the capacitor C13, the capacitor C16, the capacitor C17, the capacitor C19, the capacitor C21 and the chip U3; wherein the first pin of the chip U3 is connected with one end of the resistance R8 and the ground capacitor C6, the other end of the resistance R8 is connected with one end of the resistance R7, the third pin of the triode V3 and the ground resistance R11 respectively, the other end of the resistance R7 is connected with the 5V voltage terminal, the first pin of the triode V3 is connected with the other end of the resistance R4, the second pin of the triode V3 is grounded, the second pin of the chip U3 is connected with the 5V voltage terminal, the ground capacitor C12 and one end of the resistance R14 respectively, the third pin of the chip U3 is connected with the ground capacitor C13, the fourth pin and the fifteenth pin of the chip U3 are grounded, the sixth pin of the chip U3 is connected with the other end of the resistance R14 and the ground resistance R19 respectively, the seventh pin of the chip U3 is connected with one end of the resistance R21 and the ground capacitor C16 respectively, the other end of the resistance R21 is connected with the twentieth pin of the chip U3, the eighth pin of the chip U3 is connected with the other end of the resistance R23 and the ground capacitor C18 respectively, the ninth pin of the chip U3 is connected with the other end of the resistance R24 and the ground capacitor C20 respectively, the tenth pin of the chip U3 is connected with the other end of the resistance R25 and the ground capacitor C22 respectively, the eleventh pin of the chip U3 is connected with the 15V voltage terminal and the ground capacitor C21 respectively, the nineteenth pin of the chip U3 is connected with the ground capacitor C19 and the 15V voltage terminal respectively, the twenty-first pin of the chip U3 is connected with the ground resistance R22 and the ground capacitor C17 respectively, the twenty-second pin of the chip U3 is connected with one end of the resistance R16, the other end of the resistance R16 is connected with the 5V voltage terminal, the twenty-third pin of the chip U3 is connected with the fifth pin of the chip U2, the twenty-fourth pin of the chip U3 is connected with the ground capacitor C10 and one end of the resistance R17 respectively, the other end of the resistance R17 is connected with the 5V voltage terminal, the twenty-fifth pin of the chip U3 and the twenty-sixth pin of the chip U3 are connected with the ground capacitor C11 and one end of the resistance R15 respectively, the other end of the resistance R15 is connected with the 5V voltage terminal, the twenty-seventh pin of the chip U3 is connected with one end of the resistance R10, the other end of the resistance R10 is connected with one end of the capacitor C8, the twenty-eighth pin of the chip U3 is connected with the other end of the capacitor C8 and one end of the resistance R12 respectively, the other end of the resistance R12 and the ground capacitor C9 are connected with the output terminal.

[0014] The beneficial effects of the present application are: the present application provides a space aviation fuel pump running state monitoring circuit based on a micro-processing monitoring chip, which monitors the output Hall signal square wave of the brushless DC motor and the input voltage of the power supply, judges the running state of the motor in real time, and ensures the stable and reliable operation of the fuel pump. The pure hardware motor control scheme based on the micro-processing monitoring circuit realizes real-time monitoring of the running state of the brushless DC motor and the power supply voltage, significantly improves the reliability and safety of the aerospace fuel pump. Under the premise of not significantly increasing the cost and volume, the motor control performance is optimized to ensure that the fuel pump and the fuel pump work stably and efficiently in the complex and changeable aerospace environment, and meet the requirements of high reliability, high performance and real-time of the aerospace field. (1) The watchdog function of MAX706 is used to monitor the rotation state of the motor in real time, and the reset mechanism is automatically triggered when the motor is not working, which ensures the continuous and stable operation of the motor, greatly improves the reliability of the system, and reduces the risk of equipment downtime caused by motor failure. (2) The power supply voltage is monitored in real time by MAX706, and when the input power supply is overvoltage or undervoltage, the control of the motor is stopped immediately to protect the hardware circuit from abnormal voltage damage, enhance the safety and stability of the system, and reduce the probability of hardware damage. BRIEF DESCRIPTION OF DRAWINGS

[0015] The present application will be further illustrated in the form of exemplary embodiments, which will be described in detail with reference to the accompanying drawings. These embodiments are not limiting, and in these embodiments, the same numbers represent the same structures, wherein:

[0016] Figure 1 is an exemplary structural diagram of a space aviation fuel pump running state monitoring circuit based on a micro-processing monitoring chip according to some embodiments of the present application;

[0017] Figure 2 is an exemplary schematic diagram of a micro-processing monitoring circuit according to some embodiments of the present application;

[0018] Figure 3 is an exemplary schematic diagram of a brushless DC motor Hall sensor according to some embodiments of the present application;

[0019] Figure 4 is an exemplary schematic diagram of a power supply input circuit according to some embodiments of the present application;

[0020] Figure 5 is an exemplary schematic diagram of a driving control logic circuit according to some embodiments of the present application. DETAILED DESCRIPTION

[0021] The specific embodiments of the present application are described below to facilitate the understanding of the present application for those skilled in the art, but it should be clear that the present application is not limited to the scope of the specific embodiments, and for those skilled in the art, any changes within the spirit and scope of the present application defined and determined by the appended claims are obvious, and all the inventions utilizing the concept of the present application are within the scope of protection.

[0022] Embodiment

[0023] Figure 1 is an exemplary structure diagram of a microprocessor monitoring chip-based aerospace aviation fuel pump running state monitoring circuit according to some embodiments of the present application.

[0024] In some embodiments, a microprocessor monitoring chip-based aerospace aviation fuel pump running state monitoring circuit can include a microprocessor monitoring circuit, a brushless DC motor Hall sensor, a power input circuit and a drive control logic circuit; wherein the microprocessor monitoring circuit is connected with the brushless DC motor Hall sensor, the power input circuit and the drive control logic circuit respectively, and the brushless DC motor Hall sensor is connected with the drive control logic circuit.

[0025] In some embodiments, as shown in Figure 2 , the microprocessor monitoring circuit includes a chip U2, a resistor R2, a resistor R4, a resistor R6, a resistor R27, a voltage stabilizing diode V5 and a grounding capacitor C1; wherein the first pin of the chip U2 is connected with one end of the resistor R2, the second pin of the chip U2 is connected with one end of the resistor R27, the output end of the voltage stabilizing diode V5 and the grounding capacitor C1 respectively, the other end of the resistor R27 is connected with a 15V voltage terminal, the third pin of the chip U2 and the input end of the voltage stabilizing diode V5 are grounded, the fourth pin of the chip U2 is connected with the power input circuit, the fifth pin of the chip U2 is connected with the drive control logic circuit, the sixth pin of the chip U2 is connected with one end of the resistor R6, the other end of the resistor R6 is connected with the brushless DC motor Hall sensor, the seventh pin of the chip U2 is connected with one end of the resistor R4, the other end of the resistor R4 is connected with the drive control logic circuit, and the eighth pin of the chip U2 is connected with the other end of the resistor R2.

[0026] In some embodiments, 28V can get 15V power supply through LDO.

[0027] In some embodiments, the chip U2 can be a MAX706 chip. MAX706 is a COMS microprocessor microprocessor monitoring circuit with reset output, watchdog function and power supply monitoring function. If the watchdog monitoring input signal does not switch the level within 1.6s, the watchdog will output a low-level reset signal to make the system return to normal, preventing abnormal system operation.

[0028] In some embodiments, the MAX706 chip WDI pin is connected with the HA of the brushless DC motor Hall sensor, and when the HA has no signal input, the REST outputs high level, sets the motor speed to 0, and restarts the motor controller logic. The MAX706 chip PFI pin is connected with the power supply voltage input circuit, which monitors the power supply voltage. When the power input is greater than 42.67V, the R3 and R5 voltage division is greater than 1.25V, and the MAX706T outputs PFO high level, which disables the PWM output of the professional motor control chip; when the power input is less than 15V, the V5 voltage stabilizing tube outputs less than 4.65V, which sets the motor speed to 0 and protects the hardware circuit.

[0029] In some embodiments, as shown in Figure 3 The brushless DC motor Hall sensor includes a motor Hall plate P1, a resistor R23, a resistor R24, a resistor R25, a ground capacitor C18, a ground capacitor C20, and a ground capacitor C22. The first pin of the motor Hall plate P1 is connected with a 15V voltage terminal, the second pin of the motor Hall plate P1 is grounded, the third pin of the motor Hall plate P1 is connected with one end of the resistor R23 and the other end of the resistor R6, the fourth pin of the motor Hall plate P1 is connected with one end of the resistor R24, the fifth pin of the motor Hall plate P1 is connected with one end of the resistor R25, the other end of the resistor R23 and the ground capacitor C18 are connected with the drive control logic circuit, the other end of the resistor R24 and the ground capacitor C20 are connected with the drive control logic circuit, and the other end of the resistor R25 and the ground capacitor C22 are connected with the drive control logic circuit.

[0030] In some embodiments, the brushless DC permanent magnet motor adopts Hall signal feedback control, and the 3 Hall sensors output square wave signals during the rotation of the motor. The expression of the motor speed can be:

[0031] ;

[0032] Wherein, N represents the number of motor pole pairs, RPM represents the motor speed, and f represents the Hall signal frequency.

[0033] The RPM motor speed is proportional to the f Hall signal frequency. Monitoring the Hall frequency can know the running condition of the motor. The MCU (single-chip microcomputer) usually monitors the frequency size by software program to judge whether the motor rotates, but the aerospace aviation fuel pump is a pure hardware logic and cannot use the MCU and the corresponding software calculation method for judgment. The general technical route for detecting the motor speed by hardware is to convert the motor Hall frequency signal into a corresponding voltage value, compare the obtained voltage value with the set threshold voltage, and judge whether the motor rotates. The circuit components are complex and have low reliability.

[0034] In some embodiments, as shown in Figure 4As shown, the power input circuit includes: resistance R1, resistance R3, resistance R5, capacitor C2, capacitor C3, capacitor C4, capacitor C5, TVS tube V2 and chip U1; wherein one end of the resistance R1 is connected with the 28V input end, the other end of the resistance R1 is connected with one end of the resistance R3, one end of the capacitor C2, the first pin of the chip U1 and one end of the TVS tube V2 respectively, the other end of the resistance R3 is connected with the ground resistance R5, the ground capacitor C5 and the fourth pin of the chip U2 respectively, the other end of the TVS tube V2, the other end of the resistance C2, the third pin of the chip U1, the negative pole of the polarity capacitor C4 and one end of the capacitor C3 are grounded, the second pin of the chip U1, the positive pole of the polarity capacitor C4 and the other end of the capacitor C3 are connected with the 15V voltage end.

[0035] In some embodiments, the operating voltage range of the MAX706 chip is 1-5.5V, and the working current is about 1mA. The chip 2-pin VCC voltage monitoring threshold is 4.65V; the chip 4-pin PFI voltage monitoring is 1.25V. The voltage is used to monitor the power supply of the product.

[0036] In some embodiments, the overvoltage monitoring protection strategy is that the chip 4-pin PFI voltage monitors the bus overvoltage. The input bus voltage monitoring mode is: VPFI=V÷(R3+R5)×R5, according to the PFI voltage comparison threshold VPFI=1.25V in MAX706, the resistance R3 is 169KΩ, and the resistance R5 is 5.1KΩ, when Vinput input voltage is greater than 42.67V, the chip pin 5PFO outputs.

[0037] In some embodiments, the under-voltage monitoring protection strategy is that the chip 2-pin Vcc voltage monitors the 15V under-voltage signal. The secondary power supply 15V is obtained by converting CW7815, according to the conversion characteristics of CW7815, when Vinput input voltage is lower than 15V, the output voltage is equal to the output voltage size. Therefore, the 15Vout voltage monitoring bus low voltage condition can be monitored.

[0038] By connecting R27 as a voltage stabilizing tube V5 current limiting, V5 provides energy for MAX706 power supply after voltage stabilization. V5 selects 5.1V voltage stabilizing tube (4.8-5.4V) which stabilizes at the lowest temperature in the full temperature range of about 4.8V> monitoring threshold 4.65V. Normal will not misoperation.

[0039] When Vinput≈15Vout<15V, after R27 and R28 are divided, V5 voltage is lower than 4.8, V5 presents high resistance state with uA level of leakage current.

[0040] In some embodiments, the voltage expression of the voltage stabilizing diode V5 is: V5=15Vout÷(R27+R28)×R28, the voltage comparison threshold V5=4.65V, the resistance R27 is 2KΩ, and the resistance R28 is 1.1KΩ. When the 15Vout input voltage is less than 13V, the WDO of the pin 8 of the chip 8 acts.

[0041] The conventional hardware circuit needs at least a frequency-to-voltage circuit, a voltage reference chip and a comparison circuit to be adopted to be completed. The adoption of a chip MAX706 realizes the monitoring of the motor rotating speed and the overvoltage and undervoltage monitoring of the bus, and the design is ingenious.

[0042] In some embodiments, as Figure 5As shown, the drive control logic circuit includes: resistors R7, R8, R10, R11, R12, R14, R15, R16, R17, R19, R21, R22, a triode V3, capacitors C6, C8, C9, C10, C11, C12, C13, C16, C17, C19, C21 and a chip U3; wherein the first pin of the chip U3 is connected with one end of the resistor R8 and the ground capacitor C6, the other end of the resistor R8 is connected with one end of the resistor R7, the third pin of the triode V3 and the ground resistor R11 respectively, the other end of the resistor R7 is connected with the 5V voltage terminal, the first pin of the triode V3 is connected with the other end of the resistor R4, the second pin of the triode V3 is grounded, the second pin of the chip U3 is connected with the 5V voltage terminal, the ground capacitor C12 and one end of the resistor R14 respectively, the third pin of the chip U3 is connected with the ground capacitor C13, the fourth pin and the fifteenth pin of the chip U3 are grounded, the sixth pin of the chip U3 is connected with the other end of the resistor R14 and the ground resistor R19 respectively, the seventh pin of the chip U3 is connected with one end of the resistor R21 and the ground capacitor C16 respectively, the other end of the resistor R21 is connected with the twentieth pin of the chip U3, the eighth pin of the chip U3 is connected with the other end of the resistor R23 and the ground capacitor C18 respectively, the ninth pin of the chip U3 is connected with the other end of the resistor R24 and the ground capacitor C20 respectively, the tenth pin of the chip U3 is connected with the other end of the resistor R25 and the ground capacitor C22 respectively, the eleventh pin of the chip U3 is connected with the 15V voltage terminal and the ground capacitor C21 respectively, the nineteenth pin of the chip U3 is connected with the ground capacitor C19 and the 15V voltage terminal respectively, the twenty-first pin of the chip U3 is connected with the ground resistor R22 and the ground capacitor C17 respectively, the twenty-second pin of the chip U3 is connected with one end of the resistor R16, the other end of the resistor R16 is connected with the 5V voltage terminal, the twenty-third pin of the chip U3 is connected with the fifth pin of the chip U2, the twenty-fourth pin of the chip U3 is connected with the ground capacitor C10 and one end of the resistor R17 respectively, the other end of the resistor R17 is connected with the 5V voltage terminal, the twenty-fifth pin of the chip U3 and the twenty-sixth pin of the chip U3 are connected with the ground capacitor C11 and one end of the resistor R15 respectively, the other end of the resistor R15 is connected with the 5V voltage terminal, the twenty-seventh pin of the chip U3 is connected with one end of the resistor R10, the other end of the resistor R10 is connected with one end of the capacitor C8, the twenty-eighth pin of the chip U3 is connected with the other end of the capacitor C8 and one end of the resistor R12 respectively, the other end of the resistor R12 and the ground capacitor C9 are connected with the output terminal.

[0043] In some embodiments, the second pin of the chip U3 can output 5V voltage by itself.

[0044] Working principle: connect the VCC pin of MAX706 chip to the positive pole of stable power supply, and connect the GND pin to the negative pole of power supply to provide working power supply for the chip; connect the output pin of brushless DC motor Hall sensor to the watchdog function monitoring pin of MAX706 respectively to ensure that the signal can be accurately transmitted to MAX706 for monitoring; connect the voltage monitoring pin of MAX706 to the power input circuit through a suitable voltage dividing resistor circuit to accurately collect the power voltage signal; connect the reset signal output pin of MAX706 to the reset end of motor control circuit, and connect the control signal output pin to the enable end of motor control circuit to realize the control of motor.

[0045] According to the normal rotating speed of brushless DC motor and the Hall signal characteristics, a suitable watchdog time is set in MAX706. For example, if the minimum jump period of Hall signal is 1.6S when the motor rotates normally, it can ensure that the motor stop can be detected in time and misjudgment can be avoided. According to the normal working voltage range of aerospace equipment power supply, a reasonable undervoltage threshold is set in MAX706. For example, the normal working voltage of the equipment is 28V±2V, and the undervoltage threshold can be set to 13V. When the power voltage is detected to be lower than 13V, the motor stops working immediately.

[0046] The watchdog function WDI pin of MAX706 is connected with the output end of brushless DC motor Hall sensor. The Hall sensor can convert the mechanical rotation of the motor into an electrical signal. When the motor rotates normally, the output Hall signal of the motor will present periodic jump. MAX706 continuously monitors the signal, and a specific watchdog time is set inside. When the jump of Hall signal is detected within the set watchdog time, it can be judged that the motor is in rotating state; if no jump is detected within the time period, it is judged that the motor is in stop state. Once it is judged that the motor does not rotate, MAX706 will automatically send a reset signal to the motor control circuit to try to restart the motor speed control and make it return to normal work to maintain the continuous operation of the motor.

[0047] The voltage monitoring pin PFI of MAX706 is connected to the power input circuit for overvoltage detection, and the power VCC collects the secondary power voltage through a voltage stabilizing diode for undervoltage detection. The power input of aerospace equipment is easily affected by various factors, such as changes in aircraft attitude, power system fluctuations, etc., resulting in voltage fluctuations. MAX706 integrates a voltage comparator circuit inside, which will immediately output a control signal to the motor control circuit to control the motor to stop working when the detected power voltage is lower than the pre-set undervoltage threshold. This measure effectively avoids the hardware circuit from bearing too high or too low voltage due to abnormal power supply, thereby protecting the hardware safety of the whole system and preventing faults and damage caused by power supply problems.

[0048] In some embodiments of the present specification, a microprocessor-based monitoring chip is provided for monitoring the operating state of an aerospace fuel pump. By monitoring the output Hall signal square wave of the brushless DC motor and the input voltage of the power supply, the operating state of the motor can be determined in real time, ensuring the stable and reliable operation of the fuel pump. The pure hardware motor control scheme based on the microprocessor monitoring circuit realizes real-time monitoring of the operating state of the brushless DC motor and the power supply voltage, significantly improving the reliability and safety of the aerospace fuel pump. Without significantly increasing the cost and size, the motor control performance is optimized to ensure the stable and efficient operation of the fuel pump in the complex and variable aerospace environment, meeting the requirements of high reliability, high performance and real-time in the aerospace field. (1) The watchdog function of MAX706 is used to monitor the rotation state of the motor in real time. When the motor is not working, the reset mechanism is automatically triggered to ensure the continuous and stable operation of the motor, significantly improving the reliability of the system and reducing the risk of equipment downtime caused by motor failure. (2) MAX706 monitors the power supply voltage in real time. When the input power supply is under-voltage, the control of the motor is immediately stopped to protect the hardware circuit from abnormal voltage damage, enhance the safety and stability of the system, and reduce the probability of hardware damage.

Claims

1. A monitoring circuit for the operating status of an aerospace fuel pump based on a microprocessor monitoring chip, characterized in that, include: The system comprises a microprocessor monitoring circuit, a brushless DC motor Hall sensor, a power input circuit, and a drive control logic circuit. The microprocessor monitoring circuit monitors the motor operation and power status. The brushless DC motor Hall sensor provides feedback on the motor rotor position. The drive control logic circuit outputs a corresponding full-bridge control signal to rotate the motor based on the input brushless DC motor Hall signal. The power input circuit converts the input 28VDC to 15VDC to provide power for other currents. The microprocessor monitoring circuit is connected to the brushless DC motor Hall sensor, the power input circuit, and the drive control logic circuit. The brushless DC motor Hall sensor is connected to the drive control logic circuit. The microprocessor monitoring circuit includes: The circuit consists of chip U2, resistors R2, R4, R6, R27, Zener diode V5, and grounding capacitor C1. Specifically, the first pin of chip U2 is connected to one end of resistor R2; the second pin of chip U2 is connected to one end of resistor R27, the output terminal of Zener diode V5, and grounding capacitor C1; the other end of resistor R27 is connected to the 15V voltage terminal; the third pin of chip U2 is grounded to the input terminal of Zener diode V5; the fourth pin of chip U2 is connected to the power input circuit; the fifth pin of chip U2 is connected to the drive control logic circuit; the sixth pin of chip U2 is connected to one end of resistor R6, and the other end of resistor R6 is connected to the brushless DC motor Hall sensor; the seventh pin of chip U2 is connected to one end of resistor R4, and the other end of resistor R4 is connected to the drive control logic circuit; and the eighth pin of chip U2 is connected to the other end of resistor R2. Among them, chip U2 is the MAX706T chip.

2. The aerospace fuel pump operation status monitoring circuit based on a microprocessor monitoring chip according to claim 1, characterized in that, The brushless DC motor Hall sensor includes: The system includes a motor Hall effect sensor P1, resistors R23, R24, and R25, and grounding capacitors C18, C20, and C22. The first pin of the Hall effect sensor P1 is connected to a 15V voltage terminal, the second pin is grounded, the third pin is connected to one end of resistor R23 and the other end of resistor R6, the fourth pin is connected to one end of resistor R24, the fifth pin is connected to one end of resistor R25, the other end of resistor R23 and grounding capacitor C18 are both connected to the drive control logic circuit, the other end of resistor R24 ​​and grounding capacitor C20 are both connected to the drive control logic circuit, and the other end of resistor R25 and grounding capacitor C22 are both connected to the drive control logic circuit.

3. The aerospace fuel pump operation status monitoring circuit based on a microprocessor monitoring chip according to claim 1, characterized in that, The power input circuit includes: The circuit consists of resistors R1, R3, and R5; capacitors C2, C3, C4, and C5; a TVS diode V2; and a chip U1. One end of resistor R1 is connected to the 28V input terminal. The other end of resistor R1 is connected to one end of resistor R3, one end of capacitor C2, the first pin of chip U1, and one end of TVS diode V2. The other end of resistor R3 is connected to grounding resistor R5, grounding capacitor C5, and the fourth pin of chip U2. The other end of TVS diode V2, the other end of resistor C2, the third pin of chip U1, the negative terminal of polarized capacitor C4, and one end of capacitor C3 are grounded. The second pin of chip U1, the positive terminal of polarized capacitor C4, and the other end of capacitor C3 are all connected to the 15V voltage terminal. Chip U1 is a CW7815 chip.

4. The aerospace fuel pump operation status monitoring circuit based on a microprocessor monitoring chip according to claim 2, characterized in that, The drive control logic circuit includes: The circuit consists of resistors R7, R8, R10, R11, R12, R14, R15, R16, R17, R19, R21, and R22; transistor V3; capacitors C6, C8, C9, C10, C11, C12, C13, C16, C17, C19, and C21; and chip U3. The first pin of chip U3 is connected to one end of resistor R8 and the grounding capacitor C6. The other end of resistor R8 is connected to one end of resistor R7, the third pin of transistor V3, and the grounding resistor R11. The other end of resistor R7 is connected to a 5V power supply. With the voltage terminals connected, the first pin of transistor V3 is connected to the other end of resistor R4, and the second pin of transistor V3 is grounded. The second pin of chip U3 is connected to the 5V voltage terminal, grounding capacitor C12, and one end of resistor R14. The third pin of chip U3 is connected to grounding capacitor C13. The fourth and fifteenth pins of chip U3 are grounded. The sixth pin of chip U3 is connected to the other end of resistor R14 and grounding resistor R19. The seventh pin of chip U3 is connected to one end of resistor R21 and grounding capacitor C16. The other end of resistor R21 is connected to the twentieth pin of chip U3. The eighth pin of chip U3 is connected to the other end of resistor R23 and grounding capacitor C16. With C18 connected, pin 9 of chip U3 is connected to the other end of resistor R24 ​​and grounding capacitor C20. Pin 10 of chip U3 is connected to the other end of resistor R25 and grounding capacitor C22. Pin 11 of chip U3 is connected to the 15V voltage terminal and grounding capacitor C21. Pin 19 of chip U3 is connected to grounding capacitor C19 and the 15V voltage terminal. Pin 21 of chip U3 is connected to grounding resistor R22 and grounding capacitor C17. Pin 22 of chip U3 is connected to one end of resistor R16, and the other end of resistor R16 is connected to the 5V voltage terminal. Pin 23 of chip U3 is connected to pin 5 of chip U2. Pin 24 of chip U3 is connected to one end of ground capacitor C10 and resistor R17, with the other end of resistor R17 connected to the 5V voltage terminal. Pins 25 and 26 of chip U3 are connected to one end of ground capacitor C11 and resistor R15, with the other end of resistor R15 connected to the 5V voltage terminal. Pin 27 of chip U3 is connected to one end of resistor R10, with the other end of resistor R10 connected to one end of capacitor C8. Pin 28 of chip U3 is connected to the other end of capacitor C8 and one end of resistor R12, with the other end of resistor R12 and ground capacitor C9 both connected to the output terminal. Chip U3 is a UC3625 chip.

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