CN111521232A - On-line oil quantity measuring system and method for oil tank of diesel heavy truck - Google Patents

Abstract

The invention relates to an on-line measuring system and method for the oil quantity of a diesel heavy-duty truck fuel tank. It includes a fuel tank, a liquid level sensor, a signal conversion module, a data processing module, a data transmission module, and a monitoring platform. The liquid level sensor is set at the bottom of the fuel tank, and the liquid level sensor is connected to the signal conversion module, data processing module, data transmission module, and monitoring platform in turn. ; The random memory of the data processing module sets the liquid level data buffer, the data in the data buffer is weighted and filtered, and the liquid level is calculated by using the data in the liquid level data buffer obtained after filtering. The fuel quantity can be monitored in real time, and the fuel quantity information is not easily affected by vehicle bumps, and the fuel quantity information is more accurate.

Description

A system and method for online measurement of fuel quantity in diesel heavy truck fuel tank

technical field

The invention belongs to the technical field of on-line monitoring equipment, and in particular relates to an on-line measuring system and method for the oil quantity of a diesel heavy-duty truck fuel tank.

Background technique

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not necessarily be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art.

Diesel heavy trucks are an important transport capacity in my country's transportation industry, especially in some places with relatively large short-distance transportation such as wharves and ports, and some areas where railway transportation is not developed, diesel heavy trucks are particularly important. The fuel tanks of diesel heavy trucks are generally larger in volume and have more fuel storage capacity. During the driving process or during the suspension process, accidental fuel loss may occur. Once the diesel oil is lost, the loss will be heavy.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide an on-line measuring system and method for the oil quantity of a diesel heavy-duty truck fuel tank.

In order to solve the above technical problems, the technical scheme of the present invention is:

An on-line measurement system for fuel tank of diesel heavy-duty trucks, comprising a heavy-duty truck fuel tank, a liquid level sensor, a signal conversion module, a data processing module, a data transmission module, and a monitoring platform. module, data processing module, data transmission module, monitoring platform;

The random access memory of the data processing module sets the liquid level data buffer, and uses the data in the liquid level data buffer to calculate the liquid level.

The invention provides a measuring system for the fuel quantity of the diesel heavy truck fuel tank, which can monitor the fuel quantity in real time, and the fuel quantity information is not easily affected by the bumping of the vehicle, and the fuel quantity information is more accurate.

As some embodiments of the present invention, the online measurement system includes a display module, a real-time clock module, and an alarm device, and the data processing module is respectively connected with the display module, the real-time clock module, and the alarm device. The display module can be installed in the car, which is convenient to observe the fuel level of the fuel tank.

As some embodiments of the present invention, the liquid level sensor is a hydrostatic submerged liquid level sensor, including two hydrostatic submerged liquid level sensors for redundant processing, and the two static pressure submerged liquid level sensors are respectively connected to the signal conversion module .

As some embodiments of the present invention, the signal conversion module includes a current-to-voltage conversion circuit, a first-order RC filter circuit, a limiter circuit and a 10-bit ADC circuit; a current-to-voltage conversion circuit, a first-order RC filter circuit, a limiter circuit and a 10-bit ADC circuit; Circuits are connected sequentially.

As some embodiments of the present invention, the data processing module is connected to the data transmission module through UART, and the data processing module is connected to the display module through DO-D8.

As some embodiments of the present invention, the data transmission module is a GPRS wireless data transmission mode.

As some embodiments of the present invention, the data processing module includes a central processing unit (MCU) and a memory, the MCU is connected to a memory (EEPROM), and the memory adopts a cascading manner of three EEPROMs.

Using the online measurement method of the above-mentioned online measurement system, the specific steps are:

The liquid level sensor transmits the current signal to the signal conversion module, and the signal conversion module converts the current signal into a voltage signal;

The signal conversion module converts the current signal into a digital signal after filtering and limiting processing, and inputs it into the data processing module;

The real-time clock module transmits the time signal to the data processing module, and the data processing module stores the obtained fuel quantity signal in combination with the time information in the memory;

The data processing module uses the weighted average filtering method to calculate the liquid level, and then calculates the existing oil volume according to the specifications of the fuel tank and the parameter information calibrated by parameters;

The data processing module transmits the oil quantity signal to the display module and the data transmission module respectively, and the data transmission module transmits the signal to the monitoring platform.

As some embodiments of the present invention, the weighted average filtering method in the data processing module is as follows: a liquid level data buffer is set in the RAM, liquid level information is collected at a set frequency, and the newly collected liquid level information only updates the buffered In part, after the update, the average value of the data in the buffer is used to calculate the liquid level. In this way, the latest liquid level data only occupies a part of the average calculation, which increases the robustness and anti-interference of the liquid level value. As long as the depth of the buffer zone is sufficient, the data in the buffer zone can reflect the change of the liquid level in the mailbox within a certain period of time, and then the average value calculation can remove the fluctuation of the liquid level caused by the turbulence. Its buffer depth, sampling frequency, and the proportion of the latest sampling value in calculating the average value can be set through parameters, and if necessary, parameter calibration can be carried out through GPRS.

As some embodiments of the present invention, the calculation method of the oil quantity is as follows: calculating the volume of the oil tank according to the specification of the oil tank, and then combining the liquid level information to obtain the oil quantity information.

Beneficial effects of the present invention:

In the present invention, an on-line measuring device for fuel tank oil quantity is described, which can monitor the fuel quantity data of the fuel tank in real time no matter in the process of driving or in the parking process, and regularly send the data to the monitoring background through GPRS, and the fuel quantity appears In the event of a sudden drop, an alarm signal can also be issued, and the alarm model can control the high-power buzzer to alarm, and upload the data to the background in time.

Compared with the existing oil quantity online collection system, the accuracy of signal collection is improved, and the problem of signal fluctuation during vehicle operation is eliminated.

Description of drawings

The accompanying drawings forming a part of the present invention are used to provide further understanding of the present application, and the exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

1 is a schematic structural diagram of an on-line measurement system according to Embodiment 1 of the present invention;

Fig. 2 is the overall structure diagram of the online measurement system of the embodiment 1 of the present invention;

3 is a schematic diagram of a liquid level sensor provided in a fuel tank according to Embodiment 1 of the present invention;

4 is a power supply circuit diagram of the online measurement system of Embodiment 1 of the present invention;

Fig. 5 is the circuit diagram of the GPRS wireless data transmission module of the online measurement system of Embodiment 1 of the present invention;

Fig. 6 is the circuit diagram of the power supply part of the GPRS wireless data transmission module of the online measurement system of the embodiment 1 of the present invention;

7 is a first-order RC filter circuit and a limiter circuit diagram of the online measurement system according to Embodiment 1 of the present invention;

8 is a 10-bit ADC circuit diagram of the on-line measurement system according to Embodiment 1 of the present invention;

9 is a circuit diagram of a real-time clock module of the online measurement system according to Embodiment 1 of the present invention;

Fig. 10 is the EEPROM storage circuit diagram of the online measurement system of the embodiment 1 of the present invention;

11 is a liquid crystal display module interface circuit of the online measurement system according to Embodiment 1 of the present invention;

Fig. 12 is the GPRS module circuit diagram of the online measurement system of the embodiment 1 of the present invention;

13 is a reset circuit diagram of the online measurement system of Embodiment 1 of the present invention;

Fig. 14 is the MCU circuit diagram of Embodiment 1 of the present invention;

15 is a flow chart of the online measurement method of Embodiment 1 of the present invention;

16 is a flowchart of the data processing module of Embodiment 1 of the present invention;

17 is a signal transmission diagram of the online measurement method of Embodiment 2 of the present invention;

Among them, 1. Fuel tank, 2. Signal conversion module, 3. Data processing module, 4. Alarm device, 5. Real-time clock module, 6. Data transmission module, 7. Display module, 8. Monitoring module, 9. Liquid level sensor , 10, first-order RC filter circuit and limiter circuit, 11, 10-bit ADC circuit, 12, MCU, 13, EEPROM, 14, reset circuit.

Detailed ways

It should be noted that the following detailed description is exemplary and intended to provide further explanation of the invention. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It should be noted that the terminology used herein is for the purpose of describing specific embodiments only, and is not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly dictates otherwise, the singular is intended to include the plural as well, furthermore, it is to be understood that when the terms "comprising" and/or "including" are used in this specification, it indicates that There are features, steps, operations, devices, components and/or combinations thereof. Embodiment 1 is further described below in conjunction with the embodiments of the present invention

As shown in Fig. 1, Fig. 2, Fig. 17, in the online measurement system of fuel tank oil quantity of diesel heavy truck, two liquid level sensors 9 are arranged in the fuel tank 1, and the two liquid level sensors 9 are connected to the signal conversion module 2, data processing module 3, The data transmission module 6, the monitoring platform 8, and the data processing module 3 are respectively connected with the display module 7, the real-time clock module 5, and the alarm device 4;

The random access memory of the data processing module 3 sets a liquid level data buffer, and uses the data in the liquid level data buffer to calculate the liquid level.

The real-time clock module generates date and time, and the data processing module 3 records, stores or displays the oil quantity at a time point in combination with the time information and the oil quantity information.

The liquid level sensor 9 is a static pressure input type liquid level sensor, including two static pressure input type liquid level sensors, and the two static pressure input type liquid level sensors are respectively connected with the signal conversion module 2 .

The signal conversion module 2 adopts a current-voltage conversion circuit, a first-order RC filter circuit and a limiter circuit 10 and a 10-bit ADC circuit 11 , and the first-order RC filter circuit and the limiter circuit 10 are connected with the 10-bit ADC circuit 11 .

The data processing module 3 is connected with the data transmission module 8 through the UART, and the data processing module 3 is connected with the display module 7 through the DO-D8. The display module 7 is a liquid crystal display module.

The data transmission module 8 is a GPRS wireless data transmission module.

The data processing module 3 includes a central processing unit (MCU) 12 and a memory EEPROM 13 , and the MCU 12 is connected to the EEPROM 13 . The MCU 12 is connected to the reset circuit 14 .

Example 2

As shown in Figure 15, Figure 16, Figure 17, the process of the online oil measurement method is:

The liquid level sensor 9 transmits the current signal to the signal conversion module 2, and the signal conversion module 2 converts the current signal into a voltage signal;

The signal conversion module 2 converts the voltage signal into a digital signal and inputs it into the data processing module 3;

The real-time clock module 5 transmits the signal to the data processing module 3, and the data processing module 3 stores the obtained oil quantity signal in the memory 13;

The data processing module 3 uses the weighted average filtering method to calculate the liquid level, and then calculates the existing oil amount according to the specifications of the oil tank and the oil amount information displayed by the display module;

The data processing module transmits the oil quantity signal to the display module 7 and the data transmission module 6 respectively, and the data transmission module 6 transmits the signal to the monitoring platform 8 .

The fuel tank liquid level sensor adopts the redundant design method of two liquid level sensors. The liquid level sensor 9 outputs a 4-20mA current signal, and the signal is input to the signal conversion and filter circuit of the diesel vehicle fuel tank oil quantity online measurement system, and the current is converted through the conversion circuit. The signal is converted into a voltage signal, which is then input into the 10-bit ADC 11 through the first-order RC filter circuit and the limiter circuit 10; the ADC converts the input analog voltage signal into a digital signal and inputs it into the MCU 12; the MCU 12 receives the received The digital signal is converted by software, calculated as the liquid level and oil quantity signal of the diesel vehicle fuel tank, and then combined with the time point of the calendar clock, stored in the EEPROM 13, and displayed to the display module 7, after reaching a certain time interval (for example, 5 minutes) The fuel quantity information is sent to the GPRS wireless data transmission module through the UART port; the GPRS wireless data transmission module sends the fuel quantity information of the diesel vehicle to the monitoring background (PC) through the mobile network, and the PC monitors the historical data of the fuel tank fuel quantity of the diesel vehicle and other information; in addition, the monitoring background can also use software plug-ins to calibrate the online measurement device of diesel fuel tank fuel quantity through GPRS wireless data transmission module, such as diesel fuel tank full fuel quantity, diesel vehicle number, etc.; the reset circuit can Make sure the MCU is working properly, and the power supply part can make sure the whole unit works properly.

As shown in Figure 16, a liquid level data buffer is opened in the RAM to collect liquid level information at a set frequency. The latest collected liquid level information only updates a part of the buffer. After the update, the data in the buffer is used to calculate the average value. liquid level. The time interval for collecting liquid level data may be 0.5s.

Because the diesel vehicle has vehicle bumps in the form process, the output signal of the liquid level sensor in the fuel tank is also output with fluctuations, and the fluctuation frequency is uncertain. If the sampled liquid level data is directly used to calculate the fuel volume in the fuel tank, it will cause the Quantitative data fluctuates violently;

Up-to-date level data only takes up part of the average calculation, increasing the robustness and immunity of the level values. As long as the depth of the buffer zone is sufficient, the data in the buffer zone can reflect the change of the liquid level in the mailbox within a certain period of time, and then the average value calculation can remove the fluctuation of the liquid level caused by the turbulence. Its buffer depth, sampling frequency, and the proportion of the latest sampling value in calculating the average value can be set through parameters, and if necessary, parameter calibration can be carried out through GPRS.

As shown in Figure 3, the calculation method of fuel tank oil quantity:

The volume and shape of the fuel tank of a certain type of diesel vehicle are also fixed, generally cuboid or special-shaped. If the length, width and height of the tank are given (these data can be calibrated by GPRS) or the special-shaped body is divided into several regular geometries, the volume of the fuel tank geometry can be calculated, and the fuel tank can be filled with oil. Combined with the liquid level information output by the liquid level sensor, the current amount of oil in the tank can be calculated.

The following is an example of a circuit in an online measurement system:

The power supply circuit is shown in Figure 4:

The power supply of the diesel vehicle fuel tank oil quantity online measuring device adopts the vehicle-mounted 24V lead-acid battery, and the power supply voltage is 18V-28V. After the vehicle-mounted 24V lead-acid battery is connected to the online measurement device, after passing through the short-circuit protection self-recovery fuse and anti-reverse diode, it is input to the common mode suppressor L2, and then through the 220uF and 0.1uF filter capacitors, converted to 24V, and input to the lower-level circuit. The 24V after anti-short circuit, anti-reverse connection, common mode filtering, and capacitor filtering is input to the MCU after being divided by the resistor, and the MCU detects the power supply voltage.

The 24V power supply is converted into VCC DC voltage with a capacity of 0.5A and an output voltage of 5V through the switching power supply circuit, which provides power for each part of the circuit of the measuring device.

The GPRS circuit is shown in Figure 5: Because the GPRS module is powered by +3.3V, it needs a power supply that is converted from 5V to 3.3.V, which is realized by LDO, LM1117-3.3, and the designed power supply capacity is 0.5A.

The first-order RC filter circuit and limiter circuit are shown in Figure 6; the signal conversion and filter circuit play the role of signal conversion and filtering. The output of the liquid level sensor is a 4-20mA current signal. After being input to the detection device, the current signal is converted into a voltage signal of 0.5V-2.5V by the diode D29 and the sampling resistor R46. After filtering by the RC filter circuit, it is input into the 10-bit ADC through the limiter circuit composed of D58 and D66.

The 10-bit ADC circuit is shown in Figure 7: The 10-bit ADC adopts the successive approximation ADC, the model is TLC1543IN. This chip has 8 inputs. Due to the dual-sensor redundancy design, 2 of the inputs are used, and external access is required. reference voltage. The reference voltage is designed with a 2.5V Zener tube.

The time input circuit is a calendar clock circuit, as shown in Figure 8: the calendar clock is designed by DS1302 in Dallas, and the power supply adopts a 3.6V button battery.

The EEPROM storage circuit is shown in Figure 9: The EEPROM storage circuit adopts the way of cascading 3 pieces of EEPROM.

The display module is a liquid crystal display module, the liquid crystal display screen adopts an LCD display screen, and the interface adopts a parallel port connection method, and the circuit connection is shown in Figure 10.

The GPRS data transmission circuit diagram is shown in Figure 11: the GPRS module adopts the USR-GM3 module with the Internet of Things. The module needs to be connected to the SIM card holder and the radio frequency antenna, and communicate with the MCU through the UART interface. In addition, it needs to be connected with signals such as reset, wake-up, and connection notification.

The reset circuit adopts the external expansion reset chip to ensure the correct reset of the MCU. The reset chip adopts the chip ASM813 to realize.

The MCU circuit is shown in Figure 12, and the MCU is implemented by STC89C54.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. a diesel heavy truck fuel tank oil quantity online measurement system, is characterized in that: comprise fuel tank, liquid level sensor, signal conversion module, data processing module, data transmission module, monitoring module, liquid level sensor is arranged on the bottom of fuel tank, liquid level The sensor is sequentially connected to the signal conversion module, the data processing module, the data transmission module, and the monitoring platform; The random access memory of the data processing module sets the liquid level data buffer, and uses the data in the liquid level data buffer to calculate the liquid level. 2. The online measurement system for the fuel quantity of diesel heavy truck fuel tank according to claim 1, is characterized in that: the online measurement system comprises a display module, a real-time clock module, and an alarm device, and the data processing module is respectively associated with the display module, the real-time clock module, and the alarm device. connect. 3. The on-line measurement system of diesel heavy truck fuel tank oil quantity according to claim 1, it is characterized in that: the liquid level sensor is a static pressure input type liquid level sensor, comprising two static pressure input type liquid level sensors, two static pressure input type liquid level sensors The liquid level sensors are respectively connected with the signal conversion modules. 4. The on-line measurement system of diesel heavy truck fuel tank oil quantity according to claim 1, is characterized in that: the signal conversion module adopts current-voltage conversion circuit, first-order RC filter circuit, limiter circuit and 10-bit ADC circuit, current-voltage conversion circuit , The first-order RC filter circuit and the limiter circuit are sequentially connected with the 10-bit ADC circuit. 5. The on-line measurement system for fuel tank fuel quantity of diesel heavy truck according to claim 1, wherein the data processing module is connected with the data transmission module through UART, and the data processing module is connected with the display module through DO-D8. 6. The on-line measurement system of diesel fuel tank oil quantity according to claim 1, characterized in that: the data transmission module is a GPRS wireless data transmission module. 7. The on-line measurement system of diesel heavy truck fuel tank oil quantity according to claim 1, is characterized in that: the data processing module is a central processing unit and a memory, and the central processing unit is connected to the memory, and the memory adopts the mode of 3 EEPROM cascades. 8. utilize the on-line measuring method of the arbitrary described diesel oil tank oil quantity on-line measuring system of claim 1-7, it is characterized in that: concrete steps are: The liquid level sensor transmits the current signal to the signal conversion module, and the signal conversion module converts the current signal into a voltage signal; The signal conversion module converts the current signal into a digital signal after filtering and limiting processing, and inputs it into the data processing module; The real-time clock module transmits the time signal to the data processing module, and the data processing module stores the obtained fuel quantity signal in combination with the time information in the memory; The data processing module uses the weighted average filtering method to calculate the liquid level, and then calculates the existing oil volume according to the specifications of the fuel tank and the parameter information calibrated by parameters; The data processing module transmits the oil quantity signal to the display module and the data transmission module respectively, and the data transmission module transmits the signal to the monitoring platform. 9. the on-line measuring method of diesel heavy truck fuel tank oil quantity on-line measuring system according to claim 8, is characterized in that: the method for the weighted average filtering in the data processing module is: in RAM, set liquid level data buffer area, with Set the frequency to collect the liquid level information. The latest collected liquid level information only updates a part of the buffer. After the update, the average value of the data in the buffer is used to calculate the liquid level. 10. the on-line measurement method of the diesel heavy truck oil tank oil quantity online measurement system according to claim 8, is characterized in that: the calculation method of oil quantity is: calculate the volume of oil tank according to the specification of oil tank, then combine liquid level information, obtain Oil quantity information.

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