Carbon dioxide cylinder state monitoring method and device, electronic equipment and storage medium

Abstract

The present disclosure relates to a carbon dioxide cylinder state monitoring method and device, electronic equipment and storage medium, the device comprises: a monitoring sensing component, the component can detect the filling quantity, the deformation and temperature of the cylinder body, and control the heating of the cylinder body, when the temperature of the cylinder is lower than 0 DEG C, the monitoring sensing component can also start the heating belt to heat the cylinder, and guarantee that the temperature of the cylinder is above 0 DEG C; a control component is configured, the control component collects the data of each monitoring sensing component through a CAN communication interface, and can send the measurement results of the carbon dioxide cylinders to a remote host computer through an RS232 interface; under the action of the built-in program, the control component can complete the judgment of the state of the cylinder according to the D-S evidence theory algorithm on the basis of obtaining the data of the weighing sensor and the deformation sensor, fuse and analyze the data sent by the monitoring sensing component, comprehensively judge the probability of the problem of the cylinder, and when the probability rises, the fault can be reported in advance; the embodiment of the present disclosure can realize remote monitoring of the fire-fighting carbon dioxide cylinder, start protection measures and comprehensively judge the probability of the problem of the cylinder, and can make early warning of the fault.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a monitoring device applied to a fire-fighting automatic gas fire extinguishing system for monitoring the state of a storage type fire extinguishing carbon dioxide cylinder. BACKGROUND

[0002] In the field of automatic fire extinguishing, using carbon dioxide fire extinguishing is a major means, because carbon dioxide is clean, non-polluting, non-toxic, harmless, non-corrosive, and no residue after extinguishing, it is an excellent fire extinguishing agent and has been widely used. However, since the storage of carbon dioxide gas is high pressure storage, the pressure of the cylinder is significantly higher than atmospheric pressure, if the cylinder is not tightly sealed or there is a gas leak, the carbon dioxide gas in the cylinder will leak quickly, resulting in no gas available when the fire extinguishing gas is needed, or the gas storage is not enough, resulting in poor fire extinguishing effect. Therefore, the cylinder of the carbon dioxide fire extinguishing system needs to be checked frequently, and the leakage is found in time for replacement, resulting in high maintenance cost, and if the leakage cannot be found in time, it will have a great impact on the operation of the automatic fire extinguishing system. In addition, due to the high pressure in the bottle, if there is a quality problem in the production process of the cylinder, after the cylinder is stored for a period of time, if the cylinder has a quality problem, the cylinder will expand and deform, at this time the cylinder is very dangerous and may explode at any time, causing harm to life and property safety. Through retrieval, there is no device for monitoring the state of the carbon dioxide cylinder for fire-fighting in the prior art, although the document with publication number CN

[0003] The document with publication number CN 112815228A discloses an intelligent inflation device for SF6 operating equipment, which comprises a vacuum pumping and exhaust module, an intelligent inflation module and a pressure alarm locking module on an inflation pressure-resistant pipeline, the input end of the inflation pressure-resistant pipeline is connected to an SF6 cylinder, and the output end of the inflation pressure-resistant pipeline is connected to an electrical equipment interface. However, this improved structure cannot be applied to the state monitoring of carbon dioxide cylinders, especially cannot be applied to the state monitoring of a large number of storage type fire extinguishing carbon dioxide cylinders stored in a centralized manner. SUMMARY

[0004] The present disclosure proposes a carbon dioxide cylinder state monitoring method and device, electronic equipment and storage medium, which can solve the problem that there is no monitoring device in the prior art that can remotely monitor the state of the cylinder, realize remote inspection, and effectively warn when the cylinder has a problem, and can effectively solve the safety problem in the storage process of the carbon dioxide cylinder.

[0005] The carbon dioxide cylinder state monitoring device according to the present disclosure, basic scheme 1:

[0006] comprises a plurality of monitoring sensor assemblies, control assemblies, and power supply circuits cooperating with the monitoring sensor assemblies and control assemblies, characterized in that:

[0007] The monitoring sensor assembly and the control assembly are interconnected using a CAN bus, each monitoring sensor assembly is connected with at least 3 load sensors, 2 deformation sensors and 1 temperature sensor; the monitoring sensor assembly is built-in with a program, which can realize the functions of timing measurement and communication;

[0008] The control assembly is used for collecting the data of the monitoring sensor assembly, and the monitoring sensor assembly is built-in with a program, which can realize the functions of communication and data display;

[0009] The monitoring sensor assembly is provided with an external interface, wherein a 4-core interface is a communication and low-voltage power supply interface, and a 2-core interface is a high-voltage power interface, which can be connected to high-voltage direct current; the monitoring sensor assembly is provided with at least one internal sensor interface for connecting sensors;

[0010] The control assembly is provided with a communication interface, wherein a 4-core interface is a communication and low-voltage power supply interface for connecting the monitoring sensor assembly, and a 3-core interface is an RS485 interface supporting MODBUS protocol, which supports the host computer to read and set the data in the control device through the RS485 network; the display screen of the control assembly is used for displaying the working state of the monitoring sensor assembly and the measured data.

[0011] Further optimization is made on the basis of the first scheme to obtain the second scheme: the load sensors in the monitoring sensor assembly are constructed in the following mode:

[0012] A circular tray is used, the thickness of the tray is 5-7 mm, and the diameter of the tray is the same as the diameter of the gas cylinder, so that the gas cylinder can be placed on the tray, and three cantilever beam load sensors are installed below the tray, the cantilever beam load sensors are arranged along the edge of the tray at intervals of 120°; a waterproof sealed control box is installed at the center of the bottom of the tray, and the measurement and control circuit of the monitoring sensor assembly is in the control box.

[0013] Improvements are made on the second scheme to obtain the third scheme:

[0014] The deformation sensors in the monitoring sensor assembly are constructed in the following mode:

[0015] The deformation sensor applies a Wheatstone bridge and is equipped with a strain sensor, so that when the gas cylinder body is expanded and deformed, the voltage value output after amplification can be calculated to obtain the deformation of the cylinder body; the strain sensor is pasted on a stainless steel strap, the stainless steel strap is tied on the carbon dioxide cylinder, one end of the strap has a tightening screw, and the length of the strap is adjusted by turning the tightening screw, so as to adjust the stress of the strap.

[0016] Based on Scheme 3, Scheme 4 is further optimized: the monitoring and sensing component also has a power interface for connecting the silicone heating belt; under the control of the built-in program, the monitoring and sensing component can immediately start the silicone heating belt to heat the bottle when the monitoring and sensing component detects that the temperature is below 0℃; the silicone heating belt is an impedance element that generates heat after being energized.

[0017] Under the action of the built-in program, the control component can judge the state of the gas cylinder based on the data obtained from the weighing sensor and the deformation sensor, according to the DS evidence theory algorithm. Based on different measurement results, different composite distribution probabilities are obtained, and the probability of a problem with the gas cylinder is calculated by fusion to determine whether an alarm needs to be triggered.

[0018] The program applied to the control component in Scheme 4 embodies a method for monitoring the status of carbon dioxide cylinders, resulting in Technical Scheme 5. Its unique feature is that the control component, under the action of its built-in program, completes the judgment of the cylinder status according to the DS evidence theory algorithm, including the following steps:

[0019] The first step is to define the problem space;

[0020] Define the diagnostic states as follows: θ1 with leakage but no deformation, θ2 with no leakage but deformation, θ3 with both leakage and deformation, and an empty set Φ. Describe the entire problem space for these four states. The complete state set Ω is:

[0021] {Φ,{θ1},{θ2},{θ3},{θ1,θ2},{θ1,θ3},{θ2,θ3},{θ1,θ2,θ3}}

[0022] The second step is to Defined as a recognition framework, the calculation method within this framework is defined as follows:

[0023] Define the sensor output data certainty and recognition framework for each state based on statistical data. The probability assignment function BPA, denoted by m, is also called evidence. Evidence needs to satisfy the following conditions:

[0024]

[0025] In the formula: A is a subset of Ω, which may be one or all of them; m is the moss function, which is the probability distribution of the occurrence of each element in the complete answer set Ω, and the sum of all probability distributions is 1; BPA represents the confidence in the propositions in Θ and reflects the uncertainty.

[0026] At the same time, the confidence function Bel is defined as:

[0027]

[0028] Bel(A) represents the possibility of the proposition A being true, where B is all the subsets of A;

[0029] Redefine the likelihood function Pl as:

[0030]

[0031] Pl(A) represents the degree of belief in A being non-false, also called the unrefuted function;

[0032] The interval [0, Bel(A)] represents the confidence interval of completely supporting the proposition A, the interval [0, Pl(A)] represents the non-suspicion interval of the proposition A being non-false, and the interval [Bel(A), Pl(A)] represents the uncertainty interval of the uncertain proposition A, where

[0033] For the load cell and the deformation sensor, suppose that m1 and m2 are two different sets of BPA functions on Θ. Let represent the BPA function after the fusion of the two sensors, and define the D-S combination rule as:

[0034]

[0035] In the formula, K represents the conflict coefficient, K = ∑ Ai∩Bj≠Φ m1(A i )m2(B j ); A is the intersection of A i and B j , different combinations in A represent different states, and each state has a calculated value, and the maximum calculated value is taken as the corresponding probability value of the different states of the gas cylinder;

[0036] In the third step, when the steps described in the first step and the second step are specifically calculated, first, according to the historical observation data of multiple sensors, statistical analysis of different characteristics is performed, and the BPA function values of weight measurement and deformation measurement are set respectively, and then the combined probability function of the gas leakage θ1 and the deformation problem θ1 is calculated In the obtained combined probability value, if a combined probability value is obviously greater than other values, it can be considered that the gas cylinder may or will appear leakage or deformation, and an alarm is needed;

[0037] The alarm limit is set according to the following rules: if the weight is not up to standard, the leakage probability number must be greater than 0.6; if the deformation exceeds or does not meet the standard, the deformation probability number must be greater than 0.6.

[0038] Another application direction of the present disclosure is an electronic device, which is characterized by comprising: a processor and a memory for storing processor-executable instructions; wherein the processor is configured to invoke the instructions stored in the memory to execute the method in technical solution 5.

[0039] And a computer-readable storage medium having computer program instructions stored thereon, which is characterized by that the computer program instructions, when executed by a processor, implement the method in technical solution 5.

[0040] The above at least one technical solution adopted by one or more embodiments of the present disclosure can achieve the following beneficial effects:

[0041] The carbon dioxide cylinder monitoring device adopting the above scheme can periodically complete the state reading of all carbon dioxide cylinders, understand the storage state of the carbon dioxide cylinders, and timely discover and replace the problematic cylinders when there is a cylinder leakage or deformation problem, thereby ensuring the stability of the automatic fire extinguishing system gas source supply.

[0042] Since the measurement is periodically performed, the normal state of the cylinder can be monitored by adjusting the measurement interval time, which greatly reduces the cost of manual inspection and ensures that the problem is discovered and handled in a timely manner, thereby providing a gas source guarantee for the stable operation of the automatic fire extinguishing system.

[0043] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, but not limiting the present disclosure.

[0044] Other features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0045] The drawings incorporated into the specification and forming a part thereof, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the technical solutions of the present disclosure.

[0046] Figure 1 is a schematic diagram of the system structure of the present invention.

[0047] Figure 2 , 3 , 4 is a mechanical structure diagram of the sensing and monitoring assembly involved in the present invention.

[0048] Figure 5 is a schematic diagram of the deformation sensor structure involved in the present invention.

[0049] Figure 6 is a schematic diagram of the heating belt structure involved in the present invention.

[0050] Figure 7 is a functional circuit module diagram of the sensing monitoring assembly of the present application.

[0051] Figure 8 is a program flow chart of the sensing monitoring assembly of the present application.

[0052] Figure 9 is a circuit functional module diagram of the control assembly of the present application.

[0053] Figure 10 is a program flow chart of the control assembly of the present application.

[0054] In the figure: 1 - carbon dioxide cylinder, 2 - deformation sensor, 3 - control assembly, 4 - deformation sensor, 5 - temperature sensor, 6 - silica gel heating belt, 7 - sensing monitoring assembly, 8 - 4-core communication cable, 9 - 2-core heating cable, 10 - cylinder limit, 11 - weight sensor, 12 - foot, 13 - waterproof sealed box, 14 - cable fixing clamp, 15 - input and output jack, 16 - weighing sensor fixing bolt, 17 - tightening screw, 18 - strain sensor, 19 - stainless steel cable tie, 20 - spring, 21 - hook, 22 - sensing monitoring assembly circuit. DETAILED DESCRIPTION

[0055] Various exemplary embodiments, features, and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numbers in the drawings represent the same or similar elements or components. Although various aspects of the embodiments are illustrated in the drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

[0056] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the specific embodiments below. Those skilled in the art should understand that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, elements and circuits that are well known to those skilled in the art are not described in detail, in order to highlight the main ideas of the present disclosure.

[0057] As shown in Figure 1 , the carbon dioxide cylinder monitoring device is composed of multiple sensing monitoring assemblies 7 and control assemblies 3, and a communication network 8 connecting them, which can monitor multiple carbon dioxide cylinders 1 at the same time. Each cylinder is placed at the bottom of the sensing monitoring assembly 7, which is equipped with a sensor interface that can connect two deformation sensors 2, three weighing sensors 16 and one temperature sensor 5. These sensors are installed on the surface of the carbon dioxide cylinder. The structural diagram of the sensing monitoring assembly 7 is shown in Figure 2 , 3 and 4, which are structural diagrams from different angles.

[0058] The deformation sensor 2 is a strain sensor, the structure of which is shown in Figure 5As shown, the body of the deformation sensor is a stainless steel strip 19, with a tightening screw at one end of the strip, and a strain sensor 18 mounted on the strip. When installing, the strip is wrapped around the cylinder 1, with one end of the strip passing through the tightening screw 17. By tightening the screw 17, the length of the strip can be reduced, and the strip is gradually shortened and directly tied to the surface of the cylinder. If the strip is further tightened, the strip itself will be stretched, and the strain sensor 18 will also be stretched simultaneously, and the resistance value will increase. At this time, the deformation sensor 2 is in a pre-tightened state. When the cylinder deforms, the resistance value of the strain sensor 18 on the deformation sensor 2 will continue to increase, and by monitoring this increase, the degree of expansion of the cylinder can be monitored.

[0059] The three load sensors 16 are located at the bottom of the sensing and monitoring assembly 7, and are distributed in the tangential direction of the sensing and monitoring assembly 7 at intervals of 120°. The structure of the sensing and monitoring assembly is as shown in Figure 2 As shown, when installing, the cylinder is placed on the sensing and monitoring assembly. Due to the influence of gravity, the cantilever beam of the load sensor will be deformed, and this deformation is converted into a voltage output by the internal circuit. By measuring the voltage, the weight of the cylinder can be obtained. When the cylinder leaks, the carbon dioxide inside the cylinder escapes, and the weight of the entire cylinder becomes lighter. By monitoring the weight, the gas leakage of the cylinder can be monitored. The temperature sensor 5 is directly adsorbed on the surface of the cylinder 1 to measure the temperature of the cylinder. At the lower part of the cylinder 1, there is a soft silicone heating strip 6, the structure of which is as shown in Figure 6 As shown, the two ends of the silicone heating strip 6 are a spring 20 and a hook 21, respectively. When installing, the length of the silicone heating strip is slightly smaller than the circumference of the cylinder, and the spring 20 is used to fix the heating strip to the surface of the cylinder 1. When the temperature of the cylinder is lower than 0℃, the internal circuit of the sensing and monitoring assembly 7 will start the heating function of the silicone heating strip, and the maximum heating power is about 100W. When the temperature of the cylinder is higher than 0℃, the heating is stopped.

[0060] The waterproof sealed box 13 at the bottom of the sensing and monitoring assembly 7 is as shown in Figure 3 Figure 4As shown, the waterproof sealed box 13 contains a sensor monitoring measurement circuit 22 inside, the measurement circuit 22 is connected to three load sensors 11, and there are five external interfaces 15 on the waterproof sealed box, the first interface is a 4-core power supply communication cable 8, which is responsible for powering the sensor monitoring assembly and the sensor, among the 4-core cable, two thicker cores are responsible for power supply, and two thinner cores are CAN bus for communication; The second interface is a series interface of the first interface, also using a 4-core cable, the cable is connected inside the sealed box 13, which is convenient for connecting the next sensor monitoring assembly; The third interface connects a 2-core heating cable 9 for providing power to the heating band 6, the fourth interface is a heating band interface, which directly connects the heating band 6, inside the sensor monitoring assembly, the connection of the heating cable 9 and the heating band 6 is controlled to complete the temperature control, and the power supply of the heating power box and the sensor monitoring assembly is independent of each other. For carbon dioxide cylinders stored in places with high temperature all year round, the heating cable can not be used. For the fifth interface, it is used to connect the temperature sensor 5 and the two deformation sensors 2. Through the first and second interfaces, short cable lines can be used to connect these cylinder sensor detection modules in series to form a communication and power supply network, which can facilitate wiring.

[0061] The internal circuit structure of the sensor monitoring assembly 7 to complete its function is shown in Figure 7 The circuit takes MCU as the core, ADC as the measurement tool, CAN interface as the communication means, and NMOS as the heating switch. They complete the measurement, judgment, processing, transmission and control functions in turn under the control of the program. The 6-way sensor output is an analog voltage signal. After amplification, the 6-way signal enters the ADC. The ADC can sample the 6-way signal under the control of the MCU, and the sampling result is stored in the RAM inside the MCU. Through data processing, the final measurement result is obtained. The data processing adopts the average value seeking method, which can reduce the random error of measurement.

[0062] The internal program flow of the sensor monitoring assembly 7 is shown in Figure 8 The program has a function of sending data at a fixed time. When the measurement and transmission command line is executed, the program will set the RTC timer according to the timing parameter, and then enter the low-power state. When the timing time arrives, the RTC alarm will wake up the MCU, and the MCU will start to execute Figure 8The program flowchart shown reads the working parameters from the parameter storage area, initializes each working module, and allocates storage units; starts the ADC for cyclic data acquisition, outputs the average value of the measurement after multiple rounds of data acquisition, and performs calculation and correction on the data; then starts the CAN communication bus to send the collected data, state data, and alarm information to the control component 3 through the CAN bus. In order to ensure the reliability of the data, the data will be sent multiple times until the timeout before receiving a reply from the control component 3.

[0063] The internal program flowchart of the sensing monitoring component 7 is as shown in Figure 8 After sending the data, there is a window period for receiving commands, which is set to a fixed 15s. If more than one command is received within the 15s, the window period is reset to 15s. In this way, the control component can maintain all sensing monitoring components in a low-power state by sending data read commands. If no command is received within the 15s window period, the sensing monitoring component 7 will enter a low-power state until it is awakened by the RTC next time.

[0064] The control component 3 is composed of a housing, an LCD screen, two communication interfaces, and corresponding control circuits. The two communication interfaces are CAN interface and RS485 interface. The control component is the core of the entire network, responsible for collecting and organizing sensing monitoring data, and then displaying it on the LCD screen. At the same time, it can provide data and alarm information to other digital systems. The control component supports two communication modes: CAN for communication with multiple sensing monitoring components, and RS485 interface for communication with other control systems. The LCD screen of the control component supports touch operation, not only displaying data, but also selecting the sensing monitoring component to be controlled on the screen, and writing parameters and commands to the sensing monitoring component.

[0065] The circuit structure of the control component 3 is as shown in Figure 9 The control component 3 is divided into control core MCU, LCD for display, touch screen for input, and two communication interfaces RS485 and CAN. The CAN interface is used to connect multiple sensing monitoring components 7, and the RS485 is used to connect other control systems, acting as a MODBUS protocol slave, and can provide data for other control systems.

[0066] The program flowchart of the control component 3 is as shown in Figure 10As shown, the main program is responsible for the display and sending of data, the interrupt program is responsible for receiving data, the CAN module enters the receiving interrupt program after receiving data, and the interrupt program sets the reply received data flag bit after checking that the data is normal. When the main program detects that the reply data needs to be sent, the information is immediately sent in the main program. Similarly, the RS485 bus uses the UART module of the MCU. After receiving the MODBUS command, the module first checks whether the command is a read command. The system only responds to read commands. If a read command is received, the command length and the CRC are checked. If the check is passed, the command reply data is prepared according to the address and the number of returned data required by the command, and the data is placed in the buffer area, and the sending flag bit is set. If the serial port sending flag bit is checked in the main program during the loop, the data in the serial port buffer area is immediately sent to the serial port module. In this way, the receiving and sending are separated, and the data is returned in time. The processing of the touch input by the control component is checked in each main loop. In the main program, if there is a touch input, the coordinate range is first checked to see whether it is acceptable. Then, the corresponding data record is selected according to the coordinate range, and the CAN ID number of the record is recorded in a temporary variable. When a record is selected, the setting interface for the record is displayed, and then the corresponding function is executed according to the set parameters.

[0067] By giving Figures 1 to 10 The obtained carbon dioxide cylinder state monitoring device comprises a plurality of carbon dioxide cylinder monitoring sensor assemblies, a control assembly, a CAN bus network that can connect the devices, and a power supply circuit cooperating with the device.

[0068] The monitoring sensor assembly and the control assembly are interconnected by the CAN bus. Each monitoring sensor assembly is connected with three weighing sensors, two deformation sensors and one temperature sensor, and has one power interface for connecting a silica gel heating belt. The control assembly is the core of the entire network, responsible for collecting data of each monitoring sensor assembly in the network and judging the state of the cylinder and analyzing the availability of the system.

[0069] Each monitoring sensor assembly has two groups of external interconnection interfaces. One group of 4-core interfaces is a communication and low-voltage power supply interface, and the other group of 2-core interfaces is a high-voltage power interface that can be connected to high-voltage 48V DC. Each monitoring sensor assembly also has one group of internal sensor interfaces, which are connected with a total of six sensors. Each sensor uses 4 cores and is responsible for the power supply and reception of the sensor output signal.

[0070] Each control component has two communication interfaces, one is a 4-core communication and low-voltage power supply interface, which can connect all monitoring sensor components and use a common power supply with the monitoring sensor components, and the other is a 3-core RS485 interface supporting the MODBUS protocol, which supports the host computer to read and set data in the control device through the RS485 network, so as to control the control device as part of other measurement systems. Each control component uses a 7-inch LCD screen as a display screen, which can directly display the working state of each monitoring sensor component and the measured data.

[0071] The carbon dioxide gas cylinder state monitoring device has three physical quantity measurement functions and a temperature control function of the sensing monitoring component and a control component with CAN and RS485 two communication networks. The sensing monitoring component uses three weight sensors to measure the weight of the gas cylinder, two deformation sensors to measure the deformation of the gas cylinder body, a temperature sensor to measure the temperature of the cylinder body, and a heating control unit to control the temperature of the cylinder body. When the temperature of the cylinder body is too low, the temperature control of the cylinder body is completed, and the temperature of the cylinder body is ensured to be higher than the freezing point. The control component is the core of the device, which is composed of two interfaces (RS485 and CAN interfaces) and a LCD display screen with touch function and corresponding control circuit. The CAN bus is used to collect measurement data and alarm data of no more than 100 sensing monitoring components, and the RS485 interface provides a MODBUS interface, which can provide measurement data and alarm information of the carbon dioxide state monitoring device to other information systems.

[0072] The sensing monitoring system and the control component build a data communication network through the CAN bus. The control component is the control core of the entire network and is the center node. The sensing monitoring component is a measurement terminal and is a peripheral node. The CAN bus is a serial bus, and each sensing monitoring component has two data ports. The two ports are internally connected, which facilitates the connection of multiple sensing monitoring components and the arrangement of the monitoring network. The sensing monitoring component adopts an active uploading mode to collect data of the six sensors at regular intervals, complete data processing, and then send the data to the control component.

[0073] The monitoring sensing component has a built-in program and can realize the following functions:

[0074] Function 1, timing measurement function. The program controls the monitoring sensor assembly to complete the timing measurement, and the measurement values include: (1) measuring the output signals of the three load sensors, converting the signals into digital quantities, and summing the values of the three sensors as the weight of the carbon dioxide cylinder, which will change when there is a leak; (2) measuring the output signals of the two deformation sensors, which use a Wheatstone bridge equipped with strain sensors, and the amplified voltage value output can calculate the deformation of the bottle body when the bottle body expands; (3) measuring the output value of the temperature sensor PT1000, which uses a PT1000 platinum resistance, the resistance value increases with temperature, and the change in resistance value can be converted into a change in voltage through a Wheatstone bridge, and the voltage can be measured to obtain the temperature value. The entire testing process is timed, and the controller in the monitoring sensor assembly will complete the testing of these data according to the set time interval.

[0075] Function 2: Communication function. The program controls the monitoring sensor assembly to complete data communication through the control communication interface, and actively sends the measurement results to the control device after each measurement, including weight, deformation and temperature. At the same time, it receives commands from the control device, including: immediately return a set of measurement data; set the current value as the measurement origin; clear error information; set temperature control target 4.

[0076] Function 3: Temperature control function. By default, when the monitoring sensor assembly detects that the temperature is lower than 0℃, it immediately starts the silicone heating belt to heat the bottle body. The silicone heating belt is a resistance element that generates heat when powered on. In order to ensure the temperature of the cylinder body, the heating control algorithm uses PID algorithm to ensure that the temperature of the cylinder is around 0-1℃ when the external temperature is lower than 0℃. This temperature control target can be set to other temperature points through the network communication function.

[0077] The control assembly has a built-in program that can achieve the following functions:

[0078] Function 1: Communication function. The communication function of the control device is divided into two types: (1) CAN communication interface for communication with the monitoring sensor assembly; (2) RS485 interface for communication with the host computer.

[0079] The CAN interface uses a custom communication protocol, which specifies that the data upload method is a timed upload method, i.e. the monitoring sensor assembly uploads the component status and test data at regular intervals. If the control device does not receive data within a certain time, it indicates that there is a network failure or the monitoring sensor assembly has a disconnection failure. Within 1s after receiving the data, the control device will reply to the monitoring sensor assembly that the data has been received, avoiding repeated data transmission by the monitoring sensor assembly.

[0080] The RS485 interface uses a standard MODBUS RTU protocol, and the working mode of the control device on the RS485 interface is a slave mode, and the control device waits for a MODBUS command from the RS485 interface at any time, and when the command is received, the control device immediately organizes data and returns the data to the MODBUS host.

[0081] Function 2: Data display function, when the data uploaded by the monitoring sensor assembly is received, the control device displays the data on a 7-inch LCD screen, and the display is in the form of a table, each monitoring sensor device data occupies a row of the table, and the displayed data is weight, deformation percentage, temperature, heating state, and working state. The heating state value mainly includes heating power and maximum power, and the working state is mainly the fault code of the measurement sensor assembly, which facilitates monitoring of the running state of the entire system.

[0082] Function 4: Cylinder fault diagnosis function. According to the measurement data uploaded by the sensing and monitoring assembly, the probability of cylinder failure is predicted, and the health status of the cylinder is evaluated. According to the change of data, it is judged whether the cylinder needs to be maintained, and alarm information is given to ensure the reliability and availability of the system.

[0083] The monitoring sensor assembly realizes its function 1 by the following steps:

[0084] First, the MCU controller located in the monitoring sensor assembly completes initialization, which includes: ① PWM timer, RTC, ADC, CAN interface initialization; ② allocate relevant storage units: data storage body (weight, deformation and temperature measurement storage space); error flag, heating flag; ③ load system set values: node number, weight measurement origin value, deformation measurement origin value, data upload interval time; establish corresponding internal variables;

[0085] Then, the MUC starts to measure the values of the 6 sensors by the ADC, and the data acquisition and processing mode is as follows:

[0086] The measurement mode of the 6-channel collected data adopts a cyclic measurement mode, that is, starting from the first weight sensor, the second weight sensor, the third weight sensor, the first deformation, the second deformation, and finally the temperature value are completed in turn. The acquisition component is an external ADC chip, and the chip and the MCU use serial SPI communication mode, and only after the MCU takes away the data, the next data can be collected.

[0087] The data processing mode adopts multiple measurements, and the average value is taken as the measurement result. That is, the data is collected for at least 8 times, the collected value of each channel is accumulated in a variable each time, and after 8 times of collection, the accumulated variable is divided by 8 as the measurement result. Six data gets six digital quantities, and the digital quantity is multiplied by different proportional coefficients according to different contents represented, and a correction quantity is added, so that the final measurement result is obtained. The result is stored in the data storage body and can be used by other program modules.

[0088] The monitoring sensor assembly realizes its function 2 by the following steps:

[0089] Firstly, it is provided that the communication part of the monitoring sensor assembly has two time segments, namely a sending period and a waiting period, and the whole sending process is constantly switched between the sending period and the waiting period. After the MCU controller in the monitoring sensor assembly completes the measurement, the data is stored in the data storage body, and the data sending state information is set. When the data sending period comes, the MCU sends the data out through the CAN bus mailbox.

[0090] During the data sending process, the MCU reads the node ID value, the data sending retry number N, the state value and the alarm information from the system setting value, detects the size of the data to be sent, and prepares the data frame. The appropriate sending mailbox is selected, the data is put into the CAN mailbox, and after 1s of waiting state, it is checked whether the control device receives the ACK information. If no ACK is received, the data is sent again after 1s of waiting, and N is reduced by 1. The process is repeated until the retry number N is zero.

[0091] After the sending is completed, the communication program enters the waiting period, stops sending data, and until the waiting time period ends, the data is sent again. If the reading data command sent by the control assembly is received during the waiting process, the waiting period is ended in advance, the data sending period is entered, and the data sending is started.

[0092] The monitoring sensor assembly realizes its function 3 by the following steps:

[0093] Firstly, in the normal monitoring state, the MCU reads the temperature value in the data storage body, checks whether the temperature value is lower than 0℃, if not, waits for a period of time to read the temperature again, if lower than 0℃, starts the heating mode, sets the working state to heating state, and starts the PWM output timer.

[0094] Then, the current temperature value and the difference of 0℃ are read and sent into the PID controller, the PID controller calculates the PID control value according to the value of the control parameter, the control value is sent into the comparison register of the timer, the duty cycle of the PWM is changed, the change of the duty cycle leads to the change of the heating power of the heating component, the change of the heating power leads to the change of the temperature, the temperature is collected again, the control value is calculated again, and the closed loop control of the temperature is completed.

[0095] Finally, with the rising of the external temperature, the energy required for keeping the temperature of the gas cylinder between 0℃ and 1℃ is reduced, the duty cycle of the PWM is continuously reduced, and when the temperature is higher than 1℃, the temperature control function is stopped, and the heating state is converted into the normal monitoring state.

[0096] The control component realizes its function 1 by the following steps:

[0097] Firstly, when the system is initialized, the following work is completed: ①the initialization of the CAN communication component and the RS485 communication component is completed, including the initialization of the baud rate and the data length parameter; ②the system parameters are read, including the control component CAN ID, the MODBUS ID, the initialization of the data receiving buffer area, the initialization of the data storage area, and the establishment of the internal variables required for work; ③the initialization of the data display LCD is completed;

[0098] Then, the control component starts three threads, which respectively process the CAN communication task, the RS485 communication task and the LCD display task.

[0099] After the CAN communication is started, it is in the ready state and waits for the data uploaded by the monitoring sensor component all the time, once the data arrives, the number of the monitoring sensor component can be identified according to the CAN ID of the data frame, and then the data is stored in the data storage area corresponding to the ID.

[0100] After the RS485 task is started, it is also in the ready state and waits for the MODBUS command of the RS485 port all the time, when the command arrives, the access to the data storage area is completed according to the type of the command word and the operation address.

[0101] The control component realizes its function 2 in the LCD display task:

[0102] The LCD display task mainly handles two things, one is to draw the table on the LCD screen, and the other is to handle the touch screen event of the LCD. When drawing the table on the LCD, the number of data records in the data storage area needs to be queried, and the number of data to be displayed is calculated according to the size of the screen display range. If it exceeds the display range, the position and parameters of the split screen display also need to be calculated. After drawing the table, the data is displayed on the corresponding position of the table. One row of the table represents the measurement value of one gas cylinder, from left to right: ID number, weight, deformation, temperature, heating state and working state, and alarm parameters. The bottom color of this column of the table is blue, which is the normal state. If the bottom color of this column of the table is red and flashes, it means that there is an alarm, prompting the user to check the state of the corresponding gas cylinder.

[0103] The LCD uses a touch screen as an input interface. When a certain point of the LCD is pressed, two coordinates x and y are output, representing the coordinates of the pressed position. This coordinate, combined with the display information, can determine which information is selected. The ID value of the selected information is read out and stored in a temporary variable, thereby associating with a certain sensing and measuring component. Further, the setting interface of the sensing and measuring component is popped up. Through this interface, the gas cylinder can be set to use the current value as the reference origin of measurement, the data upload interval and the target heating temperature.

[0104] The gas cylinder state diagnosis method of the control component to realize its function 3 is completed based on the data of the weight sensor and the deformation sensor according to the following D-S evidence theory algorithm:

[0105] (1) Set the diagnosis state to include θ1 has leakage and no deformation, θ2 has no leakage and has deformation, θ3 has both leakage and deformation, and empty set Φ, and write the complete state set Ω of the four states

[0106] {Φ,{θ1},{θ2},{θ3},{θ1,θ2},{θ1,θ3},{θ2,θ3},{θ1,θ2,θ3}}

[0107] (2) Define as the recognition framework, and the calculation method is defined under this framework as follows:

[0108] Define the probability distribution function BPA of the recognition framework Θ based on the statistical data to determine the degree of sensor output data under each state, which is represented by m, also known as evidence. The evidence needs to meet the following conditions:

[0109]

[0110] ​Where: A is a subset of Ω, possibly one or all, m is the moss function, is the probability distribution of the occurrence of each element in the complete answer set Ω, and all probability distributions sum to 1, BPA represents the belief degree of the proposition in Θ and embodies uncertainty;

[0111] At the same time, define the belief function Bel as:

[0112]

[0113] Bel(A) represents the possibility of the proposition A being true, where B is all subsets of A;

[0114] Define the likelihood function Pl as:

[0115]

[0116] Pl(A) represents the belief degree of A being non-false, also known as the non-refutable function;

[0117] The interval [0, Bel(A)] represents the confidence interval of fully supporting the proposition A, the interval [0, Pl(A)] represents the non-suspicion interval of the proposition A being non-false, and the interval [Bel(A), Pl(A)] represents the uncertainty interval of the uncertain proposition A, where

[0118] For the load cell and the deformation sensor, assume that m1 and m2 are two different sets of BPA functions. Let represent the BPA function after fusion of the two sensors, and define the D-S synthesis rule as:

[0119]

[0120] Where: K represents the conflict coefficient, A is the intersection of A i and B j , different combinations in A represent different states, and each state has a calculated value, and the maximum calculated value is taken as the corresponding probability value of the different states of the gas cylinder;

[0121] (3) When using the above method to calculate specifically, first, according to the historical observation data of multiple sensors, statistical analysis of different characteristics is carried out, and the BPA function values of weight measurement and deformation measurement are set respectively, then the conflict coefficient is calculated, and the synthesis probability function on the problem space is calculated As long as the combined probability value of them is significantly greater than other values, it can be considered that the gas cylinder may or will leak or deform, and an alarm is needed. The specific calculation example is as follows:

[0122] Assume that the normal weight of the gas cylinder is 150 kg after being filled with gas, and through multiple measurements and statistics, the probability of leakage is greater than 0.9 when the measured weight is less than 145 kg. Assume that the deformation sensor measurement range is 0-20%, and after the gas cylinder is filled with gas, the deformation sensor deformation is adjusted to 1% by adjusting the deformation sensor tension bolt. Through multiple measurements and statistics, when the deformation sensor output is greater than 1.3%, the probability of deformation is greater than 0.7, and when the deformation sensor output is less than 0.7%, the probability of leakage is 0.1. Therefore, the following rules are set:

[0123] (1) If the weight is not up to standard, the leakage probability number is 0.9, or the deformation probability number is 0.1;

[0124] (2) If the deformation is out of standard or not up to standard, the deformation probability number is 0.7, or the leakage probability number is 0.1;

[0125] Due to the existence of measurement error, the measurement result also has uncertainty. If the actual weight is 144 kg and the deformation is 0.9% at a later time, and the reliability of the measurement sensor is 0.9 and 0.6, respectively, then the probability distribution functions BPA of the two sensors can be constructed as follows:

[0126] m1(A) = {Φ, {θ1}, {θ2}, {θ3}, {θ1, θ2}, {θ1, θ3}, {θ2, θ3}, {θ1, θ2, θ3}}

[0127] = {0, 0.81, 0.09, 0, 0, 0, 0.1}

[0128] Define the BPA of the deformation measurement as:

[0129] m2(A) = {Φ, {θ1}, {θ2}, {θ3}, {θ1, θ2}, {θ1, θ3}, {θ2, θ3}, {θ1, θ2, θ3}}

[0130] = {0, 0.63, 0.04, 0, 0, 0, 0.33}

[0131] Calculate the conflict coefficient

[0132]

[0133] Here, if K = 0 is calculated, it means that the evidence is in conflict and the analysis fails.

[0134] According to the DS combination rule, we have:

[0135]

[0136]

[0137] In this calculation, based on the relationships between the set members of Ω, we can also obtain:

[0138]

[0139] We can also calculate the trust function and likelihood function to further analyze the credibility of the conclusions. The calculation results of the trust function and likelihood function are as follows:

[0140] Bel({θ1})=0.895, Pl({θ1})=0.961

[0141] Bel({θ2})=0.039, Pl({θ2})=0.105

[0142] It is obvious that The value is significantly larger than the other values, and If the value falls within the support range, it indicates a leak in the gas cylinder, but no deformation, requiring a leak alarm. Similarly, different measurement results can yield different composite probability distributions. These can be used to calculate the probability of a gas cylinder malfunction and determine whether an alarm should be triggered.

Claims

1. A carbon dioxide cylinder status monitoring device, comprising a plurality of monitoring and sensing components, a control component, and a power supply circuit that cooperates with the monitoring and sensing components and the control component; The monitoring and sensing components are interconnected with the control components via a CAN bus. Each monitoring and sensing component is connected to at least three load cells, two deformation sensors, and one temperature sensor. The monitoring and sensing components have built-in programs that enable timed measurement and communication functions. The control component is used to collect data from the monitoring and sensing component, and the monitoring and sensing component has a built-in program that enables communication and data display functions; The monitoring and sensing component is provided with an external interconnection interface, of which the 4-pin interface is a communication and low-voltage power supply interface, and the 2-pin interface is a high-voltage power interface that can be connected to high-voltage DC power; the monitoring and sensing component is provided with at least one set of internal sensor interfaces for connecting sensors. The control component is equipped with a communication interface, wherein the 4-pin interface is a communication and low-voltage power supply interface for connecting the monitoring and sensing component, and the 3-pin interface is an RS485 interface that supports the MODBUS protocol, allowing the host computer to read and set data in the control device via the RS485 network; the display screen of the control component is used to display the working status of the monitoring and sensing component and the measured data. The weighing sensor in the monitoring and sensing component is constructed according to the following pattern: A circular tray with a thickness of 5-7mm and a diameter the same as that of the gas cylinder is used to allow the gas cylinder to be placed on the tray. Three cantilever beam load cells are installed under the tray, arranged along the edge of the tray at 120° intervals. A waterproof and sealed control box is installed at the center of the bottom of the tray, which contains the measurement and control circuit of the monitoring and sensing components. The deformation sensor in the monitoring and sensing assembly is constructed according to the following pattern: The deformation sensor uses a Wheatstone bridge and is equipped with a strain sensor to calculate the deformation of the cylinder body when the cylinder body expands and deforms. The strain sensor is attached to a stainless steel cable tie, which is tied to the carbon dioxide cylinder. One end of the cable tie has a tightening screw. The length of the cable tie can be adjusted by turning the tightening screw, thereby adjusting the force on the cable tie. Its features are: The monitoring and sensing component also has a power interface for connecting the silicone heating band; under the control of the built-in program, the monitoring and sensing component can immediately activate the silicone heating band to heat the bottle when it detects that the temperature is below 0°C; the silicone heating band is an impedance element that generates heat when energized. Under the action of the built-in program, the control component can judge the state of the gas cylinder based on the data obtained from the weighing sensor and the deformation sensor, according to the DS evidence theory algorithm. Based on different measurement results, different composite distribution probabilities are obtained, and the probability of a problem with the gas cylinder is calculated by fusion to determine whether an alarm needs to be triggered. The control component, under the action of its built-in program, determines the state of the gas cylinder according to the DS evidence theory algorithm, including the following steps: The first step is to define the problem space; Given the diagnostic states: θ1 with leakage but no deformation, θ2 with no leakage but deformation, θ3 with both leakage and deformation, and an empty set Φ, write out the complete state set Ω of the entire problem space Θ for these four states: {Φ,{θ1},{θ2},{θ3},{θ1,θ2},{θ1,θ3},{θ2,θ3},{θ1,θ2,θ3}} The second step is to define Θ(θ1,θ2,θ3,Φ) as the recognition frame, and the calculation method under this frame is defined as follows: Define a probability allocation function BPA, denoted by m, for the sensor output data certainty and the recognition frame Θ under each state, based on statistical data. This function is also called evidence and must satisfy the following conditions: In the formula: A is a subset of Ω, which is one or all of them; m is the moss function, which is the probability distribution of the occurrence of each element in the complete answer set Ω, and the sum of all probability distributions is 1; BPA represents the confidence in the propositions in Θ and reflects the uncertainty. Meanwhile, the confidence function Bel is defined as follows: Bel(A) represents the probability that proposition A is true, where B is all subsets of A; The likelihood function Pl is redefined as: Pl(A) represents the degree of confidence that A is not false, also known as the irrefutable function; The range [0, Bel(A)] represents the confidence interval for fully supporting proposition A, [0, Pl(A)] represents the interval of no doubt that proposition A is not false, and [Bel(A), Pl(A)] is the uncertainty interval for uncertain proposition A. , For load cells and deformation sensors, assuming m1 and m2 are two different sets of BPA functions on Θ, using... The BPA function represents the result of fusing two sensors, and the DS synthesis rule is defined as follows: In the formula: K represents the conflict coefficient, A is A i and B j The intersection of A and B, different combinations in A represent different states, and each state has a calculated value. The largest calculated value is taken as the corresponding probability value of the gas cylinder under different states. The third step, when performing specific calculations using the steps described in the first and second steps, involves first conducting statistical analysis of different characteristics based on historical observation data from multiple sensors, setting the BPA function values ​​for weight measurement and deformation measurement respectively, then calculating the conflict coefficient, and subsequently calculating the combined probability function of gas leakage θ1 and deformation problem θ1. If the combined probability value of a certain state is significantly higher than the others among the obtained combined probability values, it can be considered that the gas cylinder may be or is about to be in this state, and an alarm should be triggered. The alarm threshold can be set according to the following rules: if the weight does not meet the standard, the probability of leakage is... It must be greater than 0.6; if the deformation exceeds or fails to meet the standard, the deformation probability number will definitely be greater than 0.

6. Greater than 0.

6.

2. A method for monitoring the status of a carbon dioxide cylinder, using the device described in claim 1, characterized in that: The control component, under the action of the built-in program, completes the judgment of the gas cylinder status according to the DS evidence theory algorithm.

3. An electronic device, characterized in that, include: processor; Memory used to store processor-executable instructions; The processor is configured to invoke instructions stored in the memory to execute the method of claim 2.

4. A computer-readable storage medium having computer program instructions stored thereon, characterized in that, When the computer program instructions are executed by the processor, they implement the method described in claim 2.

Images