New energy vehicle power battery thermal runaway gas monitoring and identification system and use method

Abstract

The invention discloses a new energy vehicle power battery thermal runaway gas monitoring and identification system and a use method, and the system comprises an MEMS gas sensor module circuit which is composed of a plurality of MEMS gas sensors and is used for detecting a voltage response signal of power battery gas; the thermal modulation module circuit is connected with the MEMS gas sensor module circuit and is used for adjusting the input voltage of a heating layer in the MEMS gas sensor for thermal modulation; the WIFI main control module circuit is respectively connected with the MEMS gas sensor module circuit and the thermal modulation module circuit and is used for converting a voltage response signal detected by the MEMS gas sensor into a digital signal and controlling the thermal modulation module circuit to work; and the intelligent equipment is wirelessly connected with the WIFI main control module circuit and is used for sending an acquisition instruction to the WIFI main control module circuit, receiving voltage response digital signal data and displaying an analysis result after processing the data, so that the problems that the gas monitoring sensor is slow in response, the system is immature and the interaction is inconvenient are solved.

Description

[Technical field]

[0001] The present invention relates to the field of thermal runaway gas monitoring for power batteries, and in particular to a thermal runaway gas monitoring and identification system for power batteries of new energy vehicles and a method for using the same. [Background Technology]

[0002] The improvement of new energy vehicle intelligence and health awareness means that the out-of-control monitoring of new energy vehicle power batteries has gradually become a rigid demand. The out-of-control of lithium-ion power batteries will produce a large amount of toxic and flammable gases, so gas monitoring solutions (CO, VOCs, H2) are an important means to monitor their out-of-control.

[0003] The electronic nose industry is developing rapidly for gas monitoring. In the 1980s, Dodd, Persaud and others from the University of Warwick in the UK invented a technology (electronic nose) that imitates the animal olfactory system. The response time of electronic noses on the market for gas monitoring is generally between a few seconds and a few minutes, and it takes a few minutes to reach a stable state before each monitoring. The electronic nose system often requires more than 10 different gas response sensors to be tested in coordination. The characteristics of gas molecules are extracted by synchronously measuring the constant temperature sensor array using the difference characteristics between multi-sensor materials. Then the signal processing pattern recognition algorithm is used to perform feature analysis and output results. This solution has the problems of a large number of sensors required, large size, high power consumption, difficulty in carrying, and difficulty in integrating into tiny devices or equipment. At the same time, most electronic nose systems currently use metal oxide semiconductor gas sensors, which require higher temperatures for constant temperature testing to obtain data, and the response baseline value is prone to "drift" after long-term operation, resulting in unstable test data. [Summary of the invention]

[0004] The present invention overcomes the shortcomings of the prior art, provides a new energy vehicle power battery thermal runaway gas monitoring and identification system and use method, and solves the problems of slow response of gas monitoring sensors, immature system and inconvenient interaction.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] The thermal runaway gas monitoring and identification system for power batteries of new energy vehicles is characterized by:

[0007] The MEMS gas sensor module circuit is composed of multiple MEMS gas sensors and is used to detect the voltage response signal of the power battery gas;

[0008] A thermal modulation module circuit is connected to the MEMS gas sensor module circuit and is used to adjust the input voltage of the heating layer in the MEMS gas sensor for thermal modulation;

[0009] The WIFI main control module circuit is connected to the MEMS gas sensor module circuit and the thermal modulation module circuit respectively, and is used to convert the voltage response signal detected by the MEMS gas sensor into a digital signal, and control the operation of the thermal modulation module circuit;

[0010] The smart device is wirelessly connected to the WIFI main control module circuit, and is used to send acquisition instructions to the WIFI main control module circuit and receive voltage response digital signal data, and display analysis results after processing the data.

[0011] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized in that: it also includes:

[0012] The key circuit is connected to the WIFI main control module circuit and is used to input reset and burning control instructions;

[0013] An LED indication circuit is connected to the WIFI main control module circuit to indicate whether it is in a data collection state;

[0014] USB connection circuit, connected to external input power source for power or communication connection;

[0015] The power supply circuit is connected to the USB connection circuit and is used to rectify and step down the external input power to supply power to the USB connection circuit, the MEMS gas sensor module circuit, the thermal modulation module circuit, the WIFI main control module circuit, the button circuit, and the LED indication circuit.

[0016] The new energy vehicle power battery thermal runaway gas monitoring and identification system as described above is characterized in that the data processing algorithm in the intelligent device is an attention mechanism algorithm or a neural network algorithm.

[0017] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized in that the WIFI main control module circuit and the smart device are connected through TCP / IP protocol communication.

[0018] The new energy vehicle power battery thermal runaway gas monitoring and identification system as described above is characterized in that the MEMS gas sensor module circuit is composed of two or four MEMS gas sensors.

[0019] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized in that: the MEMS gas sensor module circuit includes a MEMS gas sensor M1, a MEMS gas sensor M2, a MEMS gas sensor M3 and a MEMS gas sensor M4;

[0020] MEMS gas sensor M1 pin 1 is connected to the thermal modulation module circuit, MEMS gas sensor M1 pin 2 is connected to the power supply VDD3V3, MEMS gas sensor M1 pin 7 is grounded, MEMS gas sensor M1 pin 8 is respectively connected to one end of resistor R13 and WIFI main control module circuit, and the other end of resistor R13 is grounded;

[0021] MEMS gas sensor M2 pin 1 is connected to the thermal modulation module circuit, MEMS gas sensor M2 pin 2 is connected to the power supply VDD3V3, MEMS gas sensor M2 pin 7 is grounded, MEMS gas sensor M2 pin 8 is respectively connected to one end of resistor R14 and the WIFI main control module circuit, and the other end of resistor R14 is grounded;

[0022] MEMS gas sensor M3 pin 1 is connected to the thermal modulation module circuit, MEMS gas sensor M3 pin 2 is connected to the power supply VDD3V3, MEMS gas sensor M3 pin 7 is grounded, MEMS gas sensor M3 pin 8 is respectively connected to one end of resistor R15 and the WIFI main control module circuit, and the other end of resistor R15 is grounded;

[0023] The MEMS gas sensor M4 pin 1 is connected to the thermal modulation module circuit, the MEMS gas sensor M4 pin 2 is connected to the power supply VDD3V3, the MEMS gas sensor M4 pin 7 is grounded, the MEMS gas sensor M4 pin 8 is respectively connected to one end of the resistor R16 and the WIFI main control module circuit, and the other end of the resistor R16 is grounded.

[0024] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized in that: the thermal modulation module circuit includes a digital-to-analog conversion chip U4, an operational amplifier U5.1, an operational amplifier U5.2, an operational amplifier U5.3 and an operational amplifier U5.4;

[0025] Pins 1-3 of the digital-to-analog conversion chip U4 are respectively connected to the WIFI main control module circuit, pin 4 of the digital-to-analog conversion chip U4 is respectively connected to the power supply VDD3V3 and one end of the capacitor C6, the other end of the capacitor C6 is grounded, pin 5 of the digital-to-analog conversion chip U4 is grounded, pin 6 of the digital-to-analog conversion chip U4 is respectively connected to one end of the capacitor C7, one end of the resistor R21, one end of the resistor R22, one end of the resistor R23, and one end of the resistor R24, the other end of the capacitor C7 is grounded,

[0026] The other end of the resistor R21 is connected to the pin 3 of the op amp U5.1, the pin 2 of the op amp U5.1 is connected to the pin 1 of the op amp U5.1 through the resistor R20, the pin 4 of the op amp U5.1 is connected to the power supply VIN, the pin 11 of the op amp U5.1 is grounded, and the pin 1 of the op amp U5.1 is connected to the EMS gas sensor M1;

[0027] The other end of the resistor R22 is connected to the pin 5 of the op amp U5.2, the pin 6 of the op amp U5.2 is connected to the pin 7 of the op amp U5.2 through the resistor R19, and the pin 7 of the op amp U5.2 is connected to the EMS gas sensor M2;

[0028] The other end of the resistor R23 is connected to the pin 10 of the op amp U5.3, the pin 9 of the op amp U5.3 is connected to the pin 8 of the op amp U5.3 through the resistor R17, and the pin 8 of the op amp U5.3 is connected to the EMS gas sensor M3;

[0029] The other end of the resistor R24 ​​is connected to the pin 12 of the operational amplifier U5.4, the pin 13 of the operational amplifier U5.4 is connected to the pin 14 of the operational amplifier U5.4 through the resistor R18, and the pin 14 of the operational amplifier U5.4 is connected to the EMS gas sensor M4.

[0030] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized in that: the WIFI main control module circuit includes a WIFI main control chip U2, the WIFI main control chip U2 pin 1 is grounded, the WIFI main control chip U2 pin 2 is respectively connected to the positive end of the electrolytic capacitor C1, one end of the resistor R4, and the power supply VDD3V3, the negative end of the electrolytic capacitor C1 is grounded, the WIFI main control chip U2 pin 3 is connected to the other end of the resistor R4, the WIFI main control chip U2 pin 4 is connected to the EMS gas sensor M1, the WIFI main control chip U2 pin 5 is connected to the EMS gas sensor M2, W Pin 6 of the IFI main control chip U2 is connected to the EMS gas sensor M3, pin 7 of the WIFI main control chip U2 is connected to the EMS gas sensor M4, pin 15 of the WIFI main control chip U2 is grounded, pin 23, pin 30 and pin 37 of the WIFI main control chip U2 are respectively connected to the digital-to-analog conversion chip U4, pin 24 of the WIFI main control chip U2 is connected to the LED indication circuit, pin 25 of the WIFI main control chip U2 is connected to the key circuit, pins 34-35 of the WIFI main control chip U2 are respectively connected to the USB connection circuit, and pins 38-39 of the WIFI main control chip U2 are respectively grounded.

[0031] The above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system is characterized by:

[0032] The key circuit includes a reset key EN and a burning key FLASH, one end of the reset key EN is grounded, the other end of the reset key EN is connected to the collector of the transistor Q1, the base of the transistor Q1 is respectively connected to the emitter of the transistor Q2 and the USB connection circuit through the resistor R9, the emitter of the transistor Q1 is respectively connected to one end of the resistor R10 and the USB connection circuit, the other end of the resistor R10 is connected to the base of the transistor Q2, and the collector of the transistor Q2 is connected to the WIFI main control module circuit; one end of the burning key FLASH is grounded, the other end of the burning key FLASH is respectively connected to the WIFI main control module circuit and one end of the resistor R5, and the other end of the resistor R5 is connected to the power supply VDD3V3;

[0033] The LED indicator circuit includes an indicator light RED and an indicator light BLUE. The negative end of the indicator light RED is grounded, and the positive end of the indicator light RED is connected to the power supply VDD3V3 through a resistor R12; the negative end of the indicator light BLUE is grounded through a resistor R11, and the positive end of the indicator light BLUE is respectively connected to one end of the resistor R6 and the WIFI main control module circuit, and the other end of the resistor R6 is grounded;

[0034] The USB connection circuit includes a Micro-USB interface USB1 and a URAT conversion chip U1, wherein pin 1 of the Micro-USB interface USB1 is connected to pin 8 of the URAT conversion chip U1 and a power supply circuit, pin 2 of the Micro-USB interface USB1 is connected to pin 5 of the URAT conversion chip U1, pin 3 of the Micro-USB interface USB1 is connected to pin 4 of the URAT conversion chip U1, and pins 4-54 and 6-7 of the Micro-USB interface USB1 are grounded respectively; pin 3 of the URAT conversion chip U1 is grounded, pins 6-7 of the URAT conversion chip U1 are connected to a power supply VDD3V3 respectively, pin 9 of the URAT conversion chip U1 is connected to a power supply VDD3V3 through a resistor R1, pins 24 and 28 of the URAT conversion chip U1 are connected to a key circuit respectively, pin 25 of the URAT conversion chip U1 is connected to a WIFI main control module circuit through a resistor R2, and pin 26 of the URAT conversion chip U1 is connected to a WIFI main control module circuit through a resistor R3;

[0035] The power supply circuit includes a voltage regulator U3, pin 1 of the voltage regulator U3 is grounded, pin 2 of the voltage regulator U3 is respectively connected to pin 4 of the voltage regulator U3, one end of capacitor C3, and one end of capacitor C4, the other ends of capacitor C3 and the other ends of capacitor C4 are respectively grounded, pin 3 of the voltage regulator U3 is respectively connected to one end of capacitor C2 and the negative end of the voltage regulator diode D1, the other end of capacitor C2 is grounded, the positive end of the voltage regulator diode D1 is connected to the Micro-USB interface USB1, pin 3 of the voltage regulator U3 outputs power supply VIN, and pin 2 of the voltage regulator U3 outputs power supply VDD3V3.

[0036] A method for using the above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system, characterized in that: it includes:

[0037] S1, the smart device sends a data collection instruction to the WIFI main control module circuit;

[0038] S2, the WIFI main control module circuit continuously writes an increasing digital signal within a certain range to the thermal modulation module circuit, so that the thermal modulation module circuit adjusts the input voltage of the MEMS gas sensor module circuit according to the cyclically increasing digital signal to achieve temperature modulation, and at the same time, the WIFI main control module circuit collects the voltage response signal of the power battery gas detected by the MEMS gas sensor module circuit and converts it into a digital signal;

[0039] S3, the WIFI main control module circuit feeds back the collected voltage response digital data to the smart device;

[0040] S4. The intelligent device processes the voltage response digital data and displays the analysis results.

[0041] The beneficial effects of the present invention are:

[0042] 1. The present invention is provided with a MEMS gas sensor module circuit, which is composed of a plurality of MEMS gas sensors, which greatly reduces the volume of the gas monitoring device and also greatly shortens the time for the gas monitoring device to collect gas characteristic data.

[0043] 2. The present invention is provided with a thermal modulation module circuit. By utilizing thermal modulation technology, the dependence on the gas-sensitive materials of the MEMS gas sensor itself and the differential characteristics between materials can be reduced, so that the gas monitoring device can realize gas detection using a small number of MEMS gas sensors, thereby reducing the size of the device, making it easy to carry and install.

[0044] 3. The present invention sets an attention mechanism algorithm in the smart device, improves the machine olfactory algorithm, and makes full use of the attention mechanism algorithm to improve the recognition accuracy and robustness of the device, speed up data processing, and the speed of reasoning and recognition. At the same time, the Internet of Things advantages of the WIFI main control module circuit composed of the ESP32WIFI ​​module are brought into play, and mobile and computer software are developed to improve the interactive convenience of the gas monitoring device system. [Drawings]

[0045] Figure 1 This is a schematic diagram of the power battery out-of-control gas monitoring and identification system of the present invention;

[0046] Figure 2 A diagram of a gas monitoring system of the present invention;

[0047] Figure 3 This is a physical picture of the MEMS gas sensor;

[0048] Figure 4 This is a schematic diagram of the circuit board of the monitoring device;

[0049] Figure 5 A schematic diagram of a USB connection circuit of the system of the present invention;

[0050] Figure 6 It is a schematic diagram of a power supply circuit of the system of the present invention;

[0051] Figure 7 It is a schematic diagram of the key circuit of the system of the present invention;

[0052] Figure 8 It is a schematic diagram of the LED indication circuit of the system of the present invention;

[0053] Fig. 9 This is a schematic diagram of the WIFI main control module circuit of the system of the present invention;

[0054] Fig.10 A schematic diagram of a MEMS gas sensor module circuit of the system of the present invention;

[0055] Fig.11 It is a circuit diagram of a thermal modulation module of the system of the present invention;

[0056] Fig.12 This is a software flowchart of the computer-side intelligent device of the present invention;

[0057] Fig.13 It is a schematic diagram of the software interface of the computer-side smart device of the present invention. [Specific implementation method]

[0058] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings.

[0059] It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly. In addition, the descriptions of "preferred", "sub-preferred", etc. in the present invention are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined as "preferred" or "sub-preferred" may explicitly or implicitly include at least one such feature.

[0060] like Figure 1 As shown, the new energy vehicle power battery thermal runaway gas monitoring and identification system includes

[0061] The MEMS gas sensor module circuit 1 is composed of a plurality of MEMS gas sensors and is used to detect the voltage response signal of the power battery gas;

[0062] The thermal modulation module circuit 2 is connected to the MEMS gas sensor module circuit 1 and is used to adjust the input voltage of the heating layer in the MEMS gas sensor for thermal modulation;

[0063] The WIFI main control module circuit 3 is connected to the MEMS gas sensor module circuit 1 and the thermal modulation module circuit 2 respectively, and is used to convert the voltage response signal detected by the MEMS gas sensor into a digital signal, and control the operation of the thermal modulation module circuit 2;

[0064] The smart device 4 is wirelessly connected to the WIFI main control module circuit 3, and is used to send acquisition instructions to the WIFI main control module circuit 3 and receive voltage response digital signal data, and display analysis results after processing the data.

[0065] The key circuit 5 is connected to the WIFI main control module circuit 3 and is used to input reset and burning control instructions;

[0066] LED indication circuit 6, connected to WIFI main control module circuit 3, used to indicate whether it is in data collection state;

[0067] USB connection circuit 7, connected to an external input power source for power or communication;

[0068] The power supply circuit 8 is connected to the USB connection circuit 7, and is used to rectify and step down the external input power to supply power to the USB connection circuit 7, the MEMS gas sensor module circuit 1, the thermal modulation module circuit 2, the WIFI main control module circuit 3, the button circuit 5, and the LED indication circuit 6.

[0069] The present invention is based on the concept of electronic nose technology and has made further improvements. It mainly uses a MEMS gas sensor module circuit 1 composed of four MEMS gas sensors with different response characteristics. Based on the MEMS gas sensor, the thermal modulation technology of the thermal modulation module circuit 2 is used to modulate the voltage to control the temperature of the heating layer of the MEMS gas sensor, thereby realizing a self-heating working mode and getting rid of the high temperature constant temperature environment required by the original electronic nose. Figure 2 As shown, according to the response changes of the MEMS gas sensor with temperature changes during the thermal modulation process, the data collected is transmitted to the client's mobile phone, computer and other smart devices 4 through the WIFI main control module circuit 3, and software is developed on the client to realize real-time data collection, display and storage, and the deep learning attention mechanism algorithm in the smart device 4 is used to process the data, analyze the characteristics, and predict the gas category.

[0070] like Figure 3As shown in the figure, MEMS gas sensors are made based on micro-electromechanical system technology, and have the advantages of small size (length and width are only 5mm), low power consumption, can be heated to high temperature with extremely low power consumption to provide a temperature environment for gas-sensitive materials (only 2V is needed to heat to 300 degrees Celsius), and high integration. This type of MEMS gas sensor is easy to integrate and easy to array design because of its high sensitivity, small size, low power consumption and low cost. Figure 4 As shown, by designing a PCB circuit board, the MEMS gas sensor module circuit 1 composed of multiple MEMS gas sensors, the WIFI main control module circuit 3 and other circuits composed of related electronic devices can be integrated into a small circuit board with a width of 42 mm and a height of 55 mm, and the small circuit board integrates the MEMS gas sensor thermal modulation control function and the WIFI and client data interaction function, which effectively solves the problem of large size and high power consumption of the electronic nose.

[0071] In thermal modulation technology, the role of a single MEMS gas sensor can be developed to the greatest extent by utilizing the thermodynamic properties of the sensing material itself, thereby reducing the use of MEMS gas sensors. In this case, only 2 or 4 MEMS gas sensors are needed. At the same time, MEMS gas sensors have high sensitivity and fast response. Compared with metal oxide semiconductor gas sensors, they can complete a thermal modulation faster, often completing a temperature modulation of 100°C-300°C within 1 second. Combined with the fast reasoning of the attention mechanism algorithm, the prediction of a gas category can be completed within a few milliseconds. Compared with the electronic nose, the entire power battery thermal runaway gas monitoring and identification system only takes about 1 second for a complete detection, which greatly reduces the detection time and is very suitable for the thermal runaway gas monitoring needs of power batteries in new energy vehicles.

[0072] In this case, the circuit structure of each module on the monitoring device circuit board is as follows: Figure 5-11 shown.

[0073] like Figure 5 As shown, the USB connection circuit 7 uses the Micro-USB interface USB1 to connect to an external 5V power supply, and at the same time connects the serial port communication between the WIFI main control module circuit 3 and the computer terminal or other smart device 4 through the Micro-USB interface USB1 to the URAT conversion chip U1 of CP2102.

[0074] like Figure 6 As shown, since general diode rectification is prone to tailing, the SS14 Schottky diode D1 is used for rectification in the power supply circuit 8, and the NCP1117 low-dropout linear regulator U3 is selected to reduce the input rectified 5V voltage to a 3.3V DC output to power other module circuits.

[0075] like Figure 7As shown, the reset button EN and the burning button FLASH in the key circuit 5 respectively control the reset and burning operations. The key circuit 5 is designed as an automatic download and burning circuit, which uses the capacitor discharge delay to delay the EN signal level, realizes the low level of port GPIO0, and enters the download mode on the rising edge of EN.

[0076] like Figure 8-9 As shown, the WIFI main control chip U2 of ESP32-WROOM-32E is selected in the WIFI main control module circuit 3, and the LED indication circuit 6 indicates the power supply and whether data collection is in progress through the indicator light RED and the indicator light BLUE.

[0077] like Fig. 9 As shown, the WIFI main control chip U2 in the WIFI main control module circuit 3 is connected to the MEMS gas sensor M1, MEMS gas sensor M2, MEMS gas sensor M3, and MEMS gas sensor M4 in the MEMS gas sensor module circuit 1 through SENSOR_VP, SENSOR_VN, GPIO34, and GPIO35 terminals, respectively, to collect and obtain the voltage response signal of the MEMS gas sensor to the detected gas, and convert it into a digital signal for processing and analysis.

[0078] like Figure 10-11 As shown, the thermal modulation of the four MEMS gas sensors in the MEMS gas sensor module circuit 1 is realized by continuously controlling the output of the digital signal of the IO port through the WIFI main control module circuit 3. A single-channel, 12-bit AD5621 digital-to-analog conversion chip U4 is selected to convert the digital signal input from the GPIO23 terminal of the WIFI main control chip U2 of the WIFI main control module circuit 3 into a voltage signal, and a four-channel thermal modulation module circuit composed of four OPA4313IPWR op amps U5.1-U5.4 is used as a voltage follower to isolate the WIFI main control module circuit 3 (signal source) and the MEMS gas sensor (load) in the MEMS gas sensor module circuit 1, reduce the impact of the load on the signal source, and ensure the accuracy and stability of the modulation voltage output by the WIFI main control module circuit 3. At the same time, in order to solve the problem that the MEMS gas sensor responds differently to the same gas in different environments and enhance the environmental robustness of this case, the four MEMS gas sensors are combined in pairs, and the thermal modulation response data of the MEMS gas sensor for a specific gas is obtained by subtraction and normalization.

[0079] In this case, a method for using the above-mentioned new energy vehicle power battery thermal runaway gas monitoring and identification system includes:

[0080] S1, the smart device 4 sends a data collection instruction to the WIFI main control module circuit 3;

[0081] S2, the WIFI main control module circuit 3 continuously writes an increasing digital signal within a certain range to the thermal modulation module circuit 2, so that the thermal modulation module circuit 2 adjusts the input voltage of the MEMS gas sensor module circuit 1 according to the cyclically increasing digital signal to achieve temperature modulation. At the same time, the WIFI main control module circuit 3 collects the voltage response signal of the power battery gas detected by the MEMS gas sensor module circuit 1 and converts it into a digital signal;

[0082] S3, the WIFI main control module circuit 3 feeds back the collected voltage response digital data to the smart device 4;

[0083] S4. The intelligent device 4 processes the voltage response digital data and displays the analysis results.

[0084] Among them, the WIFI communication part in the loading program of the WIFI main control chip U2 regards the whole system as a Client / Server model, the circuit board as a server, and smart devices such as mobile phones and computers as clients. The circuit board needs to send the data collected by the onboard MEMS gas sensor to the client through WIFI. The TCP / IP protocol is selected, and the communication is in the form of client request server response. Specifically, the client sends a request to the specified IP address, such as a start collection request, a start continuous collection request, a stop continuous collection request, etc. The server makes a corresponding action after receiving the corresponding request, and sends a data packet in the form of HTML through the HTTP port as a request response back to the client, so that the client can access the requested data.

[0085] At the same time, the main program of the thermal modulation control part of the onboard program is set as a loop. When the detection receives the start acquisition request sent by the client, the WIFI main control chip U2 starts to continuously write increasing digital signals within a certain range to the digital-to-analog conversion chip U4 through the GPIO23 terminal. For example, in the range of [4194,9834], the digital signal increases by 32 with each cycle, corresponding to the 12-bit AD5621 digital-to-analog conversion chip U4's 1.28V (4194 / 4 / 4095*5) to 3V (9834 / 4 / 4095*5) voltage. The temperature modulation function is achieved by adjusting the input voltage of the heating layer of the MEMS gas sensor.

[0086] In this case, the software interface of smart devices such as PCs is implemented based on Qt and developed using PyQt. The functions that need to be implemented in the entire software interface mainly include data collection, data display, and data processing, reasoning and prediction results. Figure 12-13 As shown, the three functions are implemented by five classes.

[0087] In this case, the interfaces of smart devices such as mobile phones are developed based on WeChat mini-programs, which are mainly used to conveniently collect data and save it locally for subsequent data processing.

[0088] In this case, the design of the data processing algorithm in the smart device is that since the gas thermal modulation response data has time series correlation, which means that there is a temporal dependency between data points, the attention mechanism algorithm is chosen as the core framework for building the algorithm model. The attention mechanism algorithm can capture the complex relationship between different time points in the data, and by dynamically assigning weights, the model can pay more attention to the time points that have a greater impact on the prediction results. This mechanism is particularly suitable for processing time series data because it can identify and emphasize key features in the data, thereby improving the model's prediction accuracy and generalization ability. In the analysis of gas thermal modulation response data, the attention mechanism algorithm can identify which time points have a more significant impact on the final result, thereby optimizing the model's decision-making process.

[0089] On the other hand, the data processing algorithms in smart devices can also be neural network algorithms such as CNN, RNN, Mamba, etc. Among them, the CNN neural network algorithm can well extract the characteristics of the data and accurately predict the results through its convolution characteristics. At the same time, the convolution calculation has stronger computational parallelism and higher training efficiency than the attention mechanism algorithm.

[0090] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or directly or indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. The thermal runaway gas monitoring and identification system for power batteries of new energy vehicles is characterized by: It comprises a MEMS gas sensor module circuit (1), which is composed of a plurality of MEMS gas sensors and is used to detect a voltage response signal of a power battery gas; A thermal modulation module circuit (2) is connected to the MEMS gas sensor module circuit (1) and is used to adjust the input voltage of the heating layer in the MEMS gas sensor for thermal modulation; The WIFI main control module circuit (3) is connected to the MEMS gas sensor module circuit (1) and the thermal modulation module circuit (2) respectively, and is used to convert the voltage response signal detected by the MEMS gas sensor into a digital signal, and to control the operation of the thermal modulation module circuit (2); The smart device (4) is wirelessly connected to the WIFI main control module circuit (3), and is used to send a collection instruction to the WIFI main control module circuit (3) and receive voltage response digital signal data, and display analysis results after processing the data.

2. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 1 is characterized in that: Also includes A key circuit (5) is connected to the WIFI main control module circuit (3) and is used to input reset and burning control instructions; An LED indication circuit (6) is connected to the WIFI main control module circuit (3) and is used to indicate whether it is in a data collection state; A USB connection circuit (7) connected to an external input power source for power or communication; The power supply circuit (8) is connected to the USB connection circuit (7) and is used to rectify and reduce the voltage of the external input power supply and then supply power to the USB connection circuit (7), the MEMS gas sensor module circuit (1), the thermal modulation module circuit (2), the WIFI main control module circuit (3), the key circuit (5), and the LED indication circuit (6).

3. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 1 is characterized in that: The data processing algorithm in the intelligent device (4) is an attention mechanism algorithm or a neural network algorithm.

4. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 1 is characterized in that: The WIFI main control module circuit (3) and the smart device (4) are connected via TCP / IP protocol communication.

5. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 1 is characterized in that: The MEMS gas sensor module circuit (1) is composed of two or four MEMS gas sensors.

6. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 1 is characterized in that: The MEMS gas sensor module circuit (1) comprises a MEMS gas sensor M1, a MEMS gas sensor M2, a MEMS gas sensor M3 and a MEMS gas sensor M4; The pin 1 of the MEMS gas sensor M1 is connected to the thermal modulation module circuit (2), the pin 2 of the MEMS gas sensor M1 is connected to the power supply VDD3V3, the pin 7 of the MEMS gas sensor M1 is grounded, the pin 8 of the MEMS gas sensor M1 is respectively connected to one end of the resistor R13 and the WIFI main control module circuit (3), and the other end of the resistor R13 is grounded; The pin 1 of the MEMS gas sensor M2 is connected to the thermal modulation module circuit (2), the pin 2 of the MEMS gas sensor M2 is connected to the power supply VDD3V3, the pin 7 of the MEMS gas sensor M2 is grounded, the pin 8 of the MEMS gas sensor M2 is respectively connected to one end of the resistor R14 and the WIFI main control module circuit (3), and the other end of the resistor R14 is grounded; The MEMS gas sensor M3 pin 1 is connected to the thermal modulation module circuit (2), the MEMS gas sensor M3 pin 2 is connected to the power supply VDD3V3, the MEMS gas sensor M3 pin 7 is grounded, the MEMS gas sensor M3 pin 8 is respectively connected to one end of the resistor R15 and the WIFI main control module circuit (3), and the other end of the resistor R15 is grounded; The MEMS gas sensor M4 pin 1 is connected to the thermal modulation module circuit (2), the MEMS gas sensor M4 pin 2 is connected to the power supply VDD3V3, the MEMS gas sensor M4 pin 7 is grounded, the MEMS gas sensor M4 pin 8 is respectively connected to one end of the resistor R16 and the WIFI main control module circuit (3), and the other end of the resistor R16 is grounded.

7. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 6 is characterized in that: The thermal modulation module circuit (2) includes a digital-to-analog conversion chip U4, an operational amplifier U5.1, an operational amplifier U5.2, an operational amplifier U5.3 and an operational amplifier U5.4; Pins 1-3 of the digital-to-analog conversion chip U4 are respectively connected to the WIFI main control module circuit (3); pin 4 of the digital-to-analog conversion chip U4 is respectively connected to the power supply VDD3V3 and one end of the capacitor C6; the other end of the capacitor C6 is grounded; pin 5 of the digital-to-analog conversion chip U4 is grounded; pin 6 of the digital-to-analog conversion chip U4 is respectively connected to one end of the capacitor C7, one end of the resistor R21, one end of the resistor R22, one end of the resistor R23, and one end of the resistor R24; the other end of the capacitor C7 is grounded; The other end of the resistor R21 is connected to the pin 3 of the op amp U5.1, the pin 2 of the op amp U5.1 is connected to the pin 1 of the op amp U5.1 through the resistor R20, the pin 4 of the op amp U5.1 is connected to the power supply VIN, the pin 11 of the op amp U5.1 is grounded, and the pin 1 of the op amp U5.1 is connected to the EMS gas sensor M1; The other end of the resistor R22 is connected to the pin 5 of the op amp U5.2, the pin 6 of the op amp U5.2 is connected to the pin 7 of the op amp U5.2 through the resistor R19, and the pin 7 of the op amp U5.2 is connected to the EMS gas sensor M2; The other end of the resistor R23 is connected to the pin 10 of the op amp U5.3, the pin 9 of the op amp U5.3 is connected to the pin 8 of the op amp U5.3 through the resistor R17, and the pin 8 of the op amp U5.3 is connected to the EMS gas sensor M3; The other end of the resistor R24 ​​is connected to the pin 12 of the operational amplifier U5.4, the pin 13 of the operational amplifier U5.4 is connected to the pin 14 of the operational amplifier U5.4 through the resistor R18, and the pin 14 of the operational amplifier U5.4 is connected to the EMS gas sensor M4.

8. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 7 is characterized in that: The WIFI main control module circuit (3) includes a WIFI main control chip U2, wherein a pin 1 of the WIFI main control chip U2 is grounded, a pin 2 of the WIFI main control chip U2 is respectively connected to the positive end of an electrolytic capacitor C1, one end of a resistor R4, and a power supply VDD3V3, a negative end of the electrolytic capacitor C1 is grounded, a pin 3 of the WIFI main control chip U2 is connected to the other end of the resistor R4, a pin 4 of the WIFI main control chip U2 is connected to an EMS gas sensor M1, a pin 5 of the WIFI main control chip U2 is connected to an EMS gas sensor M2, and a pin 6 of the WIFI main control chip U2 is connected to an EMS gas sensor The WIFI main control chip U2 pin 24 is connected to the LED indication circuit (6), the WIFI main control chip U2 pin 25 is connected to the key circuit (5), the WIFI main control chip U2 pin 34-35 are respectively connected to the USB connection circuit (7), and the WIFI main control chip U2 pin 38-39 are respectively grounded.

9. The new energy vehicle power battery thermal runaway gas monitoring and identification system according to claim 2 is characterized in that: The key circuit (5) comprises a reset key EN and a burning key FLASH, one end of the reset key EN is grounded, the other end of the reset key EN is connected to the collector of the transistor Q1, the base of the transistor Q1 is connected to the emitter of the transistor Q2 and the USB connection circuit (7) through the resistor R9, the emitter of the transistor Q1 is connected to one end of the resistor R10 and the USB connection circuit (7), the other end of the resistor R10 is connected to the base of the transistor Q2, and the collector of the transistor Q2 is connected to the WIFI main control module circuit (3); one end of the burning key FLASH is grounded, the other end of the burning key FLASH is connected to the WIFI main control module circuit (3) and one end of the resistor R5, and the other end of the resistor R5 is connected to the power supply VDD3V3; The LED indicator circuit (6) comprises an indicator light RED and an indicator light BLUE, wherein the negative terminal of the indicator light RED is grounded, and the positive terminal of the indicator light RED is connected to the power supply VDD3V3 via a resistor R12; the negative terminal of the indicator light BLUE is grounded via a resistor R11, and the positive terminal of the indicator light BLUE is respectively connected to one end of a resistor R6 and a WIFI main control module circuit (3), and the other end of the resistor R6 is grounded; The USB connection circuit (7) includes a Micro-USB interface USB1 and a URAT conversion chip U1, wherein pin 1 of the Micro-USB interface USB1 is connected to pin 8 of the URAT conversion chip U1 and a power supply circuit (8), pin 2 of the Micro-USB interface USB1 is connected to pin 5 of the URAT conversion chip U1, pin 3 of the Micro-USB interface USB1 is connected to pin 4 of the URAT conversion chip U1, and pins 4-54 and pins 6-7 of the Micro-USB interface USB1 are respectively grounded; pin 3 of the URAT conversion chip U1 is grounded, pins 6-7 of the URAT conversion chip U1 are respectively connected to a power supply VDD3V3, pin 9 of the URAT conversion chip U1 is connected to the power supply VDD3V3 via a resistor R1, pins 24 and 28 of the URAT conversion chip U1 are respectively connected to a key circuit (5), pin 25 of the URAT conversion chip U1 is connected to a WIFI main control module circuit (3) via a resistor R2, and pin 26 of the URAT conversion chip U1 is connected to a WIFI main control module circuit (3) via a resistor R3; The power supply circuit (8) includes a voltage stabilizer U3, wherein pin 1 of the voltage stabilizer U3 is grounded, pin 2 of the voltage stabilizer U3 is respectively connected to pin 4 of the voltage stabilizer U3, one end of a capacitor C3, and one end of a capacitor C4, the other end of the capacitor C3 and the other end of the capacitor C4 are respectively grounded, pin 3 of the voltage stabilizer U3 is respectively connected to one end of a capacitor C2 and a negative end of a voltage zener diode D1, the other end of the capacitor C2 is grounded, the positive end of the voltage zener diode D1 is connected to a Micro-USB interface USB1, pin 3 of the voltage stabilizer U3 outputs a power supply VIN, and pin 2 of the voltage stabilizer U3 outputs a power supply VDD3V3.

10. A method for using the thermal runaway gas monitoring and identification system for power batteries of new energy vehicles according to any one of items 1 to 9, characterized in that: Included S1, the smart device (4) sends a data collection instruction to the WIFI main control module circuit (3); S2, the WIFI main control module circuit (3) continuously writes an increasing digital signal within a certain range to the thermal modulation module circuit (2), so that the thermal modulation module circuit (2) adjusts the input voltage of the MEMS gas sensor module circuit (1) according to the cyclically increasing digital signal to achieve temperature modulation, and at the same time, the WIFI main control module circuit (3) collects the voltage response signal of the power battery gas detected by the MEMS gas sensor module circuit (1) and converts it into a digital signal; S3, the WIFI main control module circuit (3) feeds back the collected voltage response digital data to the smart device (4); S4. The intelligent device (4) processes the voltage response digital data and displays the analysis results.

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