Vehicle-mounted hydrogen concentration detection system and control method thereof

Abstract

The application discloses a vehicle-mounted hydrogen concentration detection system which comprises a main control chip, a sensor module, a CAN network communication chip and a power module in communication connection with the main control chip; the sensor module comprises a catalytic combustion type hydrogen concentration sensor and a semiconductor type hydrogen concentration sensor, output signals of the sensor module are collected by the main control chip, an amplification circuit is arranged between the sensor module and the main control chip, the main control chip analyzes corresponding concentrations according to feedback signals of the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor, and the main control chip controls power supply enable of the two groups of sensors respectively; a remote monitoring module at a vehicle end can wake up the power module through the CAN network communication chip so that the hydrogen concentration detection system enters a short-time starting mode; the power module is electrically connected with the main control chip, the sensor module and the CAN network communication chip.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of hydrogen energy, in particular to a vehicle-mounted hydrogen concentration detection system and a control method thereof. BACKGROUND

[0002] Fuel cell vehicles, as an important application direction of hydrogen energy in the transportation field, have developed rapidly in recent years. Hydrogen safety of the whole vehicle is the cornerstone for the development of fuel cell vehicles. Therefore, a vehicle-mounted hydrogen concentration sensor is needed to ensure the hydrogen safety of fuel cell vehicles.

[0003] In order to solve the above technical problems, the patent number 202221290292.3 discloses a vehicle-mounted hydrogen safety monitoring system, which comprises a safety controller, a thermal conductivity hydrogen concentration sensor, a collision sensor, an infrared hydrogen addition module, a pressure sensor, a temperature sensor, a hydrogen cylinder valve and a fuel cell main controller connected with the safety controller; the fuel cell main controller is connected with the safety controller through CAN bus, and the thermal conductivity hydrogen concentration sensor is connected with the safety controller through CAN bus, PWM or electricity.

[0004] The above-mentioned patent scheme adopts a thermal conductivity hydrogen concentration sensor, which has the advantages of low cost, no need for regular maintenance and replacement, and stability and reliability. However, the thermal conductivity hydrogen concentration sensor also has defects such as poor detection accuracy, low sensitivity and large temperature drift in gas detection. When it is applied to hydrogen fuel cell vehicles, the following problems still exist:

[0005] 1) The vehicle-mounted hydrogen concentration sensor in the current industry has a detection blind area, i.e. it cannot detect low-concentration (less than 500 ppm) hydrogen leakage, and cannot achieve early detection, early warning and early intervention for trace hydrogen leakage.

[0006] 2) After the whole vehicle power is turned off, the hydrogen concentration sensor cannot work. Once hydrogen leakage occurs when the whole vehicle is parked, the hydrogen concentration sensor cannot detect and alarm, which has certain safety hazards.

[0007] 3) The service life of the hydrogen concentration sensor cannot be guaranteed. The hydrogen concentration sensor in the current industry is only used as a signal acquisition and transmission device without related protection devices. The hydrogen concentration sensor will fail prematurely in a high-concentration hydrogen environment.

[0008] Therefore, it is necessary to improve the above-mentioned structure to overcome the above-mentioned defects. SUMMARY

[0009] The present application aims to provide a vehicle-mounted hydrogen concentration detection system and a control method thereof, which can meet the high-precision measurement requirements of hydrogen in different concentration ranges, meet the hydrogen concentration monitoring in the whole time domain, meet the long service life, and ensure the hydrogen safety of hydrogen energy vehicles.

[0010] The above technical objective of the present application is achieved by the following technical solutions:

[0011] A vehicle-mounted hydrogen concentration detection system comprises a main control chip, a sensor module, a CAN network communication chip and a power module in communication connection with the main control chip;

[0012] The sensor module comprises a catalytic combustion type hydrogen concentration sensor for high concentration detection and a semiconductor type hydrogen concentration sensor for low concentration detection, and the output signal of the sensor module is collected by the main control chip, and an amplification circuit is arranged between the sensor module and the main control chip, and the main control chip analyzes the corresponding concentration according to the feedback signal of the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor, and controls the power supply enable of the two groups of sensors respectively;

[0013] The CAN network communication chip is used for communication connection with a remote monitoring module, and the remote monitoring module sends a wake-up signal to the concentration detection system through the CAN network communication chip, and the CAN network communication chip in the concentration detection system enables the power module to provide power supply for the main control chip after receiving the wake-up signal, and the main control chip starts to work after being powered on, and controls the sensor module to enter a short-time starting mode;

[0014] The power module is electrically connected with the main control chip, the sensor module and the CAN network communication chip.

[0015] A control method of a vehicle-mounted hydrogen concentration detection system comprises the following steps:

[0016] 1) After the main control chip is powered on, the power module and the sensor module are controlled to supply power, and the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor start to work, detect the gas, and output the corresponding voltage value to the main control chip through the sampling circuit;

[0017] 2) The main control chip converts the voltage value sent by the catalytic combustion type hydrogen concentration sensor into a hydrogen concentration signal Y1, and converts the voltage value sent by the semiconductor type hydrogen concentration sensor into a hydrogen concentration signal Y2;

[0018] 3) When the hydrogen concentration signal Y1 is less than 1000ppm, the main control chip uses the hydrogen concentration signal Y2 as a reference value, and outputs the concentration signal after processing;

[0019] 4) When the hydrogen concentration signal Y1 is greater than or equal to 1000ppm, the main control chip adopts the Y1 signal value as a reference value, processes and outputs the concentration signal; the main control chip controls the power module to stop supplying power to the semiconductor hydrogen concentration sensor, and the sensor module enters the catalytic combustion hydrogen concentration sensor detection mode; when the hydrogen concentration signal Y1 is less than 1000ppm, the main control chip controls the power module to supply power to the semiconductor hydrogen concentration sensor, and the semiconductor hydrogen concentration sensor starts to work, and the main control chip adopts the hydrogen concentration signal Y2 as a reference value, processes and outputs the concentration signal.

[0020] Further, the power module includes a constant power unit and an active power unit; when the automobile starts, the active power supplies power to the main control chip, the sensor module and the CAN network communication chip; when the automobile is turned off, the active power is disconnected, and the constant power unit supplies power to the main control chip, the sensor module and the CAN network communication chip, and the main control chip, the sensor module and the CAN network communication chip enter a low-power mode, and the remote monitoring module sends a wake-up signal to the main control chip at a certain time, and the main control chip controls the sensor module to enter a short-time starting mode;

[0021] In the short-time starting mode, if the hydrogen concentration signal detected by the sensor module is not abnormal, the sensor module enters a sleep state after a set time, and waits for the next wake-up signal; if the hydrogen concentration signal detected by the sensor module is abnormal, the main control chip feeds back an abnormal value to the remote monitoring module for alarm processing, and wakes up the instrument control platform to perform sound and light alarm.

[0022] Further, the main control chip is provided with a concentration threshold value and a time threshold value;

[0023] The concentration threshold value is used to record the environmental hydrogen concentration of the sensor module, and the concentration threshold value is divided into three levels, the first level fault trigger condition is that the hydrogen concentration is higher than the first level threshold value 5000ppm or the hydrogen concentration is higher than 800ppm for a long time and lasts for more than 300s, which is used to prompt the vehicle to be repaired and checked; the concentration threshold value of the second level alarm is 10000ppm, which is used to prompt the fuel cell system to shut down and be repaired and checked; the concentration threshold value of the third level alarm is 20000ppm, which is used to prompt the vehicle to shut down immediately and be checked, and the fault is latched until the next stage is restored;

[0024] The time threshold is used for recording the total working time of the sensor module under different concentration thresholds respectively, when the working time of the sensor module under the concentration higher than 800ppm exceeds 300s, a first level failure is reported, when the total working time of the sensor module under the first level concentration threshold is greater than 1h, the failure level is upgraded, when the total working time of the sensor module under the second level concentration threshold is greater than 0.5h, the failure level is upgraded, when the total working time of the sensor module under the third level concentration threshold is greater than a set value, the main control chip controls the power module to stop supplying power to the sensor module, and records the concentration value and the failure level of the sensor module at the power-off moment.

[0025] In summary, the present application has the following advantages:

[0026] 1. By adopting a sensor module composed of a catalytic combustion type hydrogen concentration sensor and a semiconductor type hydrogen concentration sensor, the catalytic combustion type hydrogen concentration sensor is used for high concentration detection, and the semiconductor type hydrogen concentration sensor is used for low concentration detection, so that the detection blind area problem of the existing vehicle-mounted hydrogen concentration sensor can be solved.

[0027] 2. The CAN network communication chip is provided with communication network wake-up capability, and through matching with the vehicle end power supply and control, low-power sleep and communication network wake-up can be realized, and the hydrogen system safety of the vehicle can be ensured in real time.

[0028] 3. Through linkage with the vehicle control unit, the sensor module is powered and controlled under the premise of ensuring safety, so that premature failure of the sensor due to long-time working in the hydrogen immersion state is avoided, BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 is a schematic diagram of the vehicle-mounted hydrogen concentration detection system.

[0030] Figure 2 is an internal schematic diagram of the vehicle-mounted hydrogen concentration detection system.

[0031] Figure 3 is a module block diagram of the vehicle-mounted hydrogen concentration detection system.

[0032] Figure 4 is a schematic diagram of the control method of the vehicle-mounted hydrogen concentration detection system.

[0033] Figure 5 is a remote wake-up schematic diagram of the vehicle-mounted hydrogen concentration detection system. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, purposes and effects realized by the present application easy to understand, the present application is further described below in combination with the drawings and specific embodiments.

[0035] As Figure 1 , Figure 2 and Figure 3 shown, the application presents a vehicle-mounted hydrogen concentration detection system, characterized in that it comprises a main control chip, a sensor module, a CAN network communication chip and a power module in communication connection with the main control chip;

[0036] The sensor module comprises a catalytic combustion type hydrogen concentration sensor for high concentration detection and a semiconductor type hydrogen concentration sensor for low concentration detection, the signal output signal of the sensor module is collected by the main control chip, an amplifying circuit is arranged between the sensor module and the main control chip, the main control chip analyzes the corresponding concentration according to the feedback signals of the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor, and controls the power supply enable of the two groups of sensors respectively;

[0037] The CAN network communication chip is used for communication connection with a remote monitoring module, the remote monitoring module sends a wake-up signal to the main control chip through the CAN network communication chip, and the main control chip controls the sensor module to enter a short-time starting mode according to the wake-up signal;

[0038] The power module is electrically connected with the main control chip, the sensor module and the CAN network communication chip.

[0039] The catalytic combustion type hydrogen concentration sensor can detect a large range of concentrations while having the advantages of short starting time and fast response, and the mainstream hydrogen concentration sensor in the industry currently adopts the principle of catalytic combustion. However, catalytic combustion is sensitive to environmental temperature, and it is not accurate to test at low concentration. It is difficult to accurately test the hydrogen concentration below 1000 ppm.

[0040] The semiconductor type hydrogen concentration sensor has high sensitivity at low concentration and is suitable for detection in low concentration environment. It adopts a metal oxide film attached to a ceramic base to make an impedance element, and the resistance changes with the gas content. However, the sensitivity will decrease significantly at a higher hydrogen concentration, and such hydrogen-sensitive elements need to be used after a long initial recovery or stabilization time.

[0041] The application adopts a semiconductor and catalytic combustion composite sensor module, and through the control of the main control chip on the two types of sensors, full-range high-precision detection can be realized. The specific implementation method is as follows:

[0042] Referring to Figure 4 , a control method of a vehicle-mounted hydrogen concentration detection system, comprising the following steps:

[0043] 1) the main control chip is powered on, the power module sensor module supplies power, the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor start to work, detect the gas, and output the corresponding voltage value to the main control chip through the sampling circuit;

[0044] 2) the main control chip converts the voltage value sent by the catalytic combustion type hydrogen concentration sensor into a hydrogen concentration signal Y1, and converts the voltage value sent by the semiconductor type hydrogen concentration sensor into a hydrogen concentration signal Y2;

[0045] 3) when the hydrogen concentration signal Y1 is less than 1000ppm, the main control chip uses the hydrogen concentration signal Y2 as a reference value, and outputs the concentration signal after processing;

[0046] 4) when the hydrogen concentration signal Y1 is greater than or equal to 1000ppm, the main control chip uses the Y1 signal value as a reference value, and outputs the concentration signal after processing; the main control chip controls the power module to stop supplying power to the semiconductor type hydrogen concentration sensor, and the sensor module enters a catalytic combustion type hydrogen concentration sensor detection mode; when the hydrogen concentration signal Y1 is less than 1000ppm, the main control chip controls the power module to supply power to the semiconductor type hydrogen concentration sensor, the semiconductor type hydrogen concentration sensor starts to work, and the main control chip uses the hydrogen concentration signal Y2 as a reference value, and outputs the concentration signal after processing.

[0047] Referring to Figure 5 , in order to ensure that the hydrogen concentration sensor can monitor the vehicle during the whole vehicle power-off period, the scheme further provides a CAN network communication chip, the CAN network communication chip uses TJA1145 and has a communication network wake-up capability, through matching with the whole vehicle power supply and control, low-power sleep and communication network wake-up can be realized, and the hydrogen system safety of the vehicle can be ensured in real time, and the specific implementation method is as follows:

[0048] The power module in the embodiment includes a constant power unit and an activation power unit; when the automobile starts, the activation power supplies power to the main control chip, the sensor module and the CAN network communication chip; when the automobile is turned off, the activation power is disconnected, the constant power unit supplies power to the main control chip, the sensor module and the CAN network communication chip, the main control chip, the sensor module and the CAN network communication chip enter a low-power mode, and the remote monitoring module sends a wake-up signal to the main control chip at a time, and the main control chip controls the sensor module to enter a short-time starting mode;

[0049] In the short-time starting mode, if the hydrogen concentration signal detected by the sensor module is not abnormal, the sensor module enters a sleep state after a set time length ends, and waits for the next wake-up signal; if the hydrogen concentration signal detected by the sensor module is abnormal, the main control chip feeds back an abnormal value to the remote monitoring module for alarm processing, and wakes up the instrument central control platform to perform sound and light alarm.

[0050] In addition, in order to realize long service life of the sensor, the power supply of the sensor module is controlled under the premise of ensuring safety through linkage with the vehicle control unit, so as to avoid premature failure of the sensor due to long-time work in the hydrogen immersion state, and the specific implementation method is as follows:

[0051] The concentration threshold is used to record the environmental hydrogen concentration of the sensor module, and the concentration threshold is divided into three levels, the first level concentration threshold is 5000ppm, which is used to prompt the vehicle to overhaul and troubleshoot; the concentration threshold of the second alarm is 10000ppm, which is used to prompt the fuel cell system to shut down and overhaul and troubleshoot; the concentration threshold of the third alarm is 20000ppm, which is used to prompt the vehicle to shut down immediately and troubleshoot, and the fault is latched until the next stage is restored.

[0052] The time threshold is used to record the total working time of the sensor module under different concentration thresholds, respectively, when the total working time of the sensor module under the first concentration threshold is greater than 1h, the fault level is upgraded; when the total working time of the sensor module under the second concentration threshold is greater than 0.5h, the fault level is upgraded; when the total working time of the sensor module under the third concentration threshold is greater than the set value, the main control chip controls the power module to stop supplying power to the sensor module, and records the concentration value and fault level of the sensor module at the power-off moment.

[0053] In this paper, the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer", "vertical", "horizontal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of expressing the technical solution clearly and conveniently, therefore cannot be understood as a limitation on the present application.

[0054] In this paper, the terms "including", "containing" or any other variant thereof are intended to cover non-exclusive inclusion, in addition to including the listed elements, other elements not explicitly listed can also be included.

[0055] The basic principles, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A hydrogen concentration detection system for a vehicle, characterized by comprising: The sensor module includes a catalytic combustion type hydrogen concentration sensor for high concentration detection and a semiconductor type hydrogen concentration sensor for low concentration detection, the signal output of the sensor module is connected to the AD sampling pin of the main control chip after being amplified by an amplification circuit, the main control chip analyzes the corresponding concentration according to the feedback signals of the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor, and controls the power supply enable of the two groups of sensors respectively; The CAN network communication chip is used for communication connection with a remote monitoring module, the remote monitoring module sends a wake-up signal to the concentration detection system through the CAN network communication chip, the CAN network communication chip in the concentration detection system enables the power module to provide power supply for the main control chip after receiving the wake-up signal, the main control chip starts to work, and controls the sensor module to enter a short-time starting mode; The power module is electrically connected with the main control chip, the sensor module and the CAN network communication chip. The method comprises the following steps:

2. A control method of an in-vehicle hydrogen concentration detection system characterized by comprising: 1) After the main control chip is powered on, the power module and the sensor module are controlled to supply power, and the catalytic combustion type hydrogen concentration sensor and the semiconductor type hydrogen concentration sensor start to work, detect the gas, and output corresponding voltage values to the main control chip through a sampling circuit; 2) The main control chip converts the voltage value sent by the catalytic combustion type hydrogen concentration sensor into a hydrogen concentration signal Y1, and converts the voltage value sent by the semiconductor type hydrogen concentration sensor into a hydrogen concentration signal Y2; 4) When the hydrogen concentration signal Y1 is greater than or equal to 1000ppm, the main control chip takes the Y1 signal value as a reference value, processes and then outputs a concentration signal to the outside; the main control chip controls the power module to stop supplying power to the semiconductor type hydrogen concentration sensor, and the sensor module enters a catalytic combustion type hydrogen concentration sensor detection mode; when the hydrogen concentration signal Y1 is less than 1000ppm, the main control chip controls the power module to supply power to the semiconductor type hydrogen concentration sensor, the semiconductor type hydrogen concentration sensor starts to work, and the main control chip takes the hydrogen concentration signal Y2 as a reference value, processes and then outputs a concentration signal to the outside. The power module includes a constant power unit and an activation power unit; when the automobile starts, the activation power supplies power to the main control chip, the sensor module and the CAN network communication chip; when the automobile is turned off, the activation power is disconnected, the constant power unit supplies power to the main control chip, the sensor module and the CAN network communication chip, the main control chip, the sensor module and the CAN network communication chip enter a low-power mode, and the remote monitoring module sends a wake-up signal to the main control chip at a fixed time, and the main control chip controls the sensor module to enter a short-time starting mode; ​ 3. The control method of the in-vehicle hydrogen concentration detection system according to claim 2, characterized by ​ In the short-time starting mode, if the hydrogen concentration signal detected by the sensor module is normal, the sensor module enters the sleep state after the set time length ends, and waits for the next wake-up signal; if the hydrogen concentration signal detected by the sensor module is abnormal, the main control chip feeds back an abnormal value to the remote monitoring module for alarm processing, and wakes up the instrument control platform to perform sound and light alarm.

4. The control method of the in-vehicle hydrogen concentration detection system according to claim 2, characterized by The main control chip is internally provided with a concentration threshold value and a time threshold value; The concentration threshold value is used to record the environmental hydrogen concentration of the sensor module, and the concentration threshold value is divided into three levels, the first level fault trigger condition is that the hydrogen concentration is higher than the first level threshold value 5000ppm or the hydrogen concentration is higher than 800ppm for a long time and lasts for more than 300s, which is used to prompt the whole vehicle to be overhauled; the concentration threshold value of the second level alarm is 10000ppm, which is used to prompt the fuel cell system to shut down for overhauling; the concentration threshold value of the third level alarm is 20000ppm, which is used to prompt the whole vehicle to shut down immediately for troubleshooting, and the fault is latched until the next stage is restored; The time threshold value is used to record the total working time of the sensor module under different concentration threshold values, respectively, when the working time of the sensor module under the concentration higher than 800ppm is more than 300s, the first level fault is reported, and when the total working time of the sensor module under the first level concentration threshold value is greater than 1h, the fault level is upgraded; When the total working time of the sensor module under the second level concentration threshold value is greater than 0.5h, the fault level is upgraded; When the total working time of the sensor module under the third level concentration threshold value is greater than the set value, the main control chip controls the power module to stop supplying power to the sensor module, and records the concentration value and the fault level of the sensor module at the power-off moment.

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