阅读说明：本技术 一种基于差压的燃油液位感应传感系统 (Fuel liquid level sensing system based on differential pressure ) 是由 张曦 邓海龙 于 2021-08-25 设计创作，主要内容包括：本发明提出了一种基于差压的燃油液位感应传感系统,包括设置在燃油箱中的燃油泵,还包括设置在燃油泵上的第一压力测量模块和第二压力测量模块,所述第一压力测量模块的压力数据输出端与第二压力测量模块的第一压力数据输入端相连,控制器根据接收到的压力数据计算其燃油箱的液位高度,将其显示在仪表盘或/和中控屏上,当其燃油箱的液位高度小于或者等于预设液位高度阈值,则在仪表盘或/和中控屏上发出警报。本发明能够燃油箱内的液位高度进行测量显示,便于驾驶者实时了解燃油箱状况,增强驾驶者的体验。(The invention provides a fuel liquid level sensing system based on differential pressure, which comprises a fuel pump arranged in a fuel tank, a first pressure measurement module and a second pressure measurement module which are arranged on the fuel pump, wherein the pressure data output end of the first pressure measurement module is connected with the first pressure data input end of the second pressure measurement module, a controller calculates the liquid level height of the fuel tank according to the received pressure data and displays the liquid level height on an instrument panel or/and a central control screen, and when the liquid level height of the fuel tank is smaller than or equal to a preset liquid level height threshold value, an alarm is sent out on the instrument panel or/and the central control screen. The invention can measure and display the liquid level in the fuel tank, is convenient for a driver to know the condition of the fuel tank in real time and enhances the experience of the driver.)

1. The fuel liquid level sensing system based on differential pressure comprises a fuel pump (6) arranged in a fuel tank (3), and is characterized by further comprising a first pressure measuring module and a second pressure measuring module which are arranged on the fuel pump (6), wherein a pressure data output end of the first pressure measuring module is connected with a first pressure data input end of the second pressure measuring module, the first pressure measuring module is used for measuring a first pressure value in the fuel tank (3) and transmitting the measured first pressure value to the second pressure measuring module, a pressure data output end of the second pressure measuring module is connected with a pressure data input end of a controller, the second pressure measuring module is used for measuring a second pressure value in the fuel tank (3) and transmitting the measured second pressure value and the first pressure value, which is received by the second pressure measuring module and measured by the first pressure measuring module, to the controller, the first pressure measuring module and the second pressure measuring module are different in measuring height, and the distance from the second pressure measuring module to the bottom of the fuel tank (3) is smaller than the distance from the first pressure measuring module to the bottom of the fuel tank (3);

the controller calculates the liquid level height of the fuel tank (3) according to the received pressure data, displays the liquid level height on an instrument panel or/and a central control screen, and gives an alarm on the instrument panel or/and the central control screen when the liquid level height of the fuel tank (3) is smaller than or equal to a preset liquid level height threshold value.

2. The differential pressure based fuel level sensing system of claim 1, further comprising a flow sensor disposed in a fuel delivery line of the fuel pump (6) for measuring an amount of fuel injected by the fuel pump (6) into the engine, a flow data output of the flow sensor being coupled to a flow data input of the controller.

3. The differential pressure-based fuel level sensing system according to claim 1, characterized in that a fuel tank (5) is further provided in the fuel tank (3), the fuel pump (6) is provided in the fuel tank (5), an oil filter hole is provided at the bottom of the fuel tank (5), an oil filter screen (8) for filtering fuel impurities in the fuel tank (3) is provided on the oil filter hole, M vent holes (1) are provided at the upper end of the tank body of the fuel tank (5), and M is a positive integer greater than or equal to 1;

the oil filter is characterized in that a three-way pipe (7) is arranged in the oil filter box (5), a first port of the three-way pipe (7) is connected with the oil filter hole, and a second port of the three-way pipe (7) is connected with an exhaust hole of the fuel pump (6).

4. The differential pressure based fuel level sensing system of claim 1, further comprising a mounting structure that varies a distance of the first pressure measurement module from a bottom of the fuel tank (3), the mounting structure comprising:

two groups of mounting and fixing side plates which are vertically arranged on the periphery of the fuel pump (6), wherein the first pressure measurement module fixing mounting seat can be embedded between the two groups of mounting and fixing side plates, and a plurality of groups of mounting holes are uniformly distributed on the mounting and fixing side plates;

the first pressure measurement module is detachably mounted on the first pressure measurement module fixed mounting seat, and adjusting claws detachably mounted with the mounting holes are arranged on two sides of the first pressure measurement module fixed mounting seat;

the first pressure measurement module fixing mounting seat is detachably mounted with the mounting hole through the adjusting claw.

5. A control method of a fuel level sensing system based on differential pressure is characterized by comprising the following steps:

s1, when the automobile is not started, measuring the liquid level height of the fuel tank (3);

s2, when the automobile is running, the liquid level height of the fuel tank (3) is measured and displayed on the instrument panel or/and the central control screen.

6. The method of controlling a differential pressure based fuel level sensing system according to claim 5, comprising the steps of, in step S1:

s11, the second pressure measurement module determines whether the first pressure value measured by the first pressure measurement module is less than or equal to a preset first pressure threshold:

if the first pressure value measured by the first pressure measurement module is smaller than or equal to a preset first pressure threshold value, the second pressure measurement module transmits the first pressure value measured by the first pressure measurement module to the controller; at the moment, the second pressure measuring module does not collect the second pressure value, and an alarm is sent out on an instrument panel or/and a central control screen when the automobile runs;

if the first pressure value measured by the first pressure measurement module is larger than a preset first pressure threshold value, the first pressure measurement module continues to measure the first pressure value in the fuel tank (3); step S12 is executed;

s12, the controller receives the first pressure value and the second pressure value sent by the second pressure measurement module; the controller judges whether the first pressure value is larger than or equal to a preset second pressure threshold value:

if the first pressure value is greater than or equal to a preset second pressure threshold value, and the preset second pressure threshold value is greater than the preset first pressure threshold value, calculating the liquid level height, wherein the liquid level height calculation method comprises the following steps:

s121, calculating the liquid level height measured by the first pressure measurement module;

s122, calculating the liquid level height measured by the second pressure measurement module;

s123, judging the liquid level height H measured by the first pressure measurement module₁And the liquid level height H measured by the second pressure measurement module₂The relationship between:

if it isStep S124 is executed;

if it isStep S125 is executed;

S124，

h represents the liquid level height of the automobile when the automobile is not started, wherein the liquid level height is obtained according to a first pressure value measured by the first pressure measuring module and a second pressure value measured by the second pressure measuring module;

S125，

where min (,) represents the smaller of them.

7. The method of controlling a differential pressure based fuel level sensing system according to claim 5, comprising the steps of, in step S2:

s21, obtaining the real-time flow value measured by the flow sensor when the automobile runs, and recording the value as Q_t；

S22, calculating the volume of fuel consumed before the T moment of the automobile;

s23, according to the volume V of consumed fuel before T time calculated in the step S22_TCalculating the descending height value of the fuel tank (3);

and S24, calculating the liquid level height of the fuel tank (3) according to the descending height value h of the fuel tank (3) calculated in the step S23.

8. The method of controlling a differential pressure based fuel level sensing system according to claim 5, further comprising in step S2:

the level height H of the fuel tank (3) when the vehicle is in operation₀And if the liquid level is less than or equal to the preset liquid level height threshold, an alarm is given out on an instrument panel or/and a central control screen.

9. The method of controlling a differential pressure based fuel level sensing system according to claim 8, further comprising in step S2:

the level height H of the fuel tank (3) when the vehicle is in operation₀And if the preset first liquid level height threshold is smaller than or equal to the preset first liquid level height threshold, the controller sends a control signal, and the control signal is an automobile stop signal to stop the automobile from running.

10. The method of claim 5 further comprising providing a refuel identification module inside the vehicle fuel tank door to automatically refuel the vehicle.

Technical Field

The invention relates to the technical field of automobiles, in particular to a fuel level sensing and sensing system based on differential pressure.

Background

The automobile displays how much of the oil level must depend on the oil level sensor. The existing oil level sensor displays the change of resistance value through the sliding between a thick film resistor disc and a brush disc, and finally calculates the amount of gasoline in an oil tank through signal change. The structure is that the electric brush piece is directly arranged on the surface of the resistance piece and is directly contacted with gasoline. The round contact is in pressure contact with the resistor disc, so that the pressure required for pressing the contact on the resistor disc needs to be very high, and is 0.2-0.3N. Less than 0.2N will result in contact of no more than 0.3N and a reduction in the number of wear resistances. So that the contact level must be uniform. If the pressure generated on the ceramic chip conductors is different, so that the wear-resisting times are different, the service life of the automobile oil level sensor is long or short, and the reliability is poor. Just because the pressure of the brush piece is difficult to control, the brush piece slides back and forth on the conductor to grind off the conduction band, and the phenomenon that the sensor is frequently damaged can occur. Secondly, the resistance card is soaked in gasoline, and because the purity of the gasoline is not high or the pressure of the electric brush card pressed on the resistance card is too large, the phenomena of surface oxidation, conduction band cutting and the like of the resistance card can be generated after the resistance card is used for a long time. And thus the displayed resistance value is incorrect, the oil level is displayed inaccurately.

Disclosure of Invention

The invention aims to at least solve the technical problems in the prior art, and particularly creatively provides a fuel liquid level sensing system based on differential pressure.

In order to achieve the above object, the present invention provides a differential pressure-based fuel level sensing system, which includes a fuel pump disposed in a fuel tank, and further includes a first pressure measurement module and a second pressure measurement module disposed on the fuel pump, wherein a pressure data output end of the first pressure measurement module is connected to a first pressure data input end of the second pressure measurement module, the first pressure measurement module is configured to measure a first pressure value in the fuel tank and transmit the measured first pressure value to the second pressure measurement module, a pressure data output end of the second pressure measurement module is connected to a pressure data input end of a controller, the second pressure measurement module is configured to measure a second pressure value in the fuel tank and transmit the measured second pressure value and the first pressure value measured by the first pressure measurement module received by the second pressure measurement module to the controller, the first pressure measuring module and the second pressure measuring module are different in measuring height, and the distance from the second pressure measuring module to the bottom of the fuel tank is smaller than the distance from the first pressure measuring module to the bottom of the fuel tank;

and the controller calculates the liquid level height of the fuel tank according to the received pressure data, displays the liquid level height on an instrument panel or/and a central control screen, and gives an alarm on the instrument panel or/and the central control screen when the liquid level height of the fuel tank is less than or equal to a preset liquid level height threshold value.

In a preferred embodiment of the invention, the fuel pump further comprises a flow sensor arranged on the fuel conveying pipeline of the fuel pump and used for measuring the fuel quantity sprayed to the engine by the fuel pump, and the flow data output end of the flow sensor is connected with the flow data input end of the controller.

In a preferred embodiment of the invention, a fuel tank is further arranged in the fuel tank, the fuel pump is arranged in the fuel tank, the bottom of the fuel tank is provided with a fuel filtering hole, the fuel filtering hole is provided with a fuel filtering net for filtering fuel impurities in the fuel tank, the upper end of a tank body of the fuel tank is provided with M vent holes, and M is a positive integer greater than or equal to 1;

the oil filter is characterized by further comprising a three-way pipe arranged in the oil filter box, a first port of the three-way pipe is connected with the oil filter hole, a second port of the three-way pipe is connected with an exhaust hole of the fuel pump, and a third port of the three-way pipe is not connected and is opened to the inner space of the oil filter box. When the exhaust hole discharges fuel or air is started, air in the fuel pump is discharged, and after the air is discharged, a small amount of fuel can be continuously discharged from the exhaust hole during normal operation), the fluid flows through the three-way pipe from the horizontal direction, the fuel in the fuel tank is sucked by the first port of the three-way pipe and is discharged into the fuel tank from the third port of the three-way pipe according to the Bernoulli principle, and the fuel in the fuel tank can be kept at the determined fuel level even when the fuel level in the fuel tank is low, so that the fuel pump can conveniently suck the fuel.

In a preferred embodiment of the present invention, further comprising a mounting structure for changing a distance between the first pressure measurement module and a bottom of the fuel tank, the mounting structure comprising:

the two groups of mounting and fixing side plates are vertically arranged on the periphery of the fuel pump, the first pressure measurement module fixing mounting seat can be embedded between the two groups of mounting and fixing side plates, and a plurality of groups of mounting holes are uniformly distributed on the mounting and fixing side plates;

the first pressure measurement module is detachably mounted on the first pressure measurement module fixed mounting seat, and adjusting claws detachably mounted with the mounting holes are arranged on two sides of the first pressure measurement module fixed mounting seat;

the first pressure measurement module fixing mounting seat is detachably mounted with the mounting hole through the adjusting claw.

The invention also discloses a control method of the fuel liquid level sensing and sensing system based on differential pressure, which comprises the following steps:

s1, when the automobile is not started, measuring the liquid level height of the fuel tank;

and S2, measuring the liquid level height of the fuel tank when the automobile runs, and displaying the liquid level height on an instrument panel or/and a central control screen.

In a preferred embodiment of the present invention, step S1 includes the following steps:

s11, the second pressure measurement module determines whether the first pressure value measured by the first pressure measurement module is less than or equal to a preset first pressure threshold:

if the first pressure value measured by the first pressure measurement module is smaller than or equal to a preset first pressure threshold value, the second pressure measurement module transmits the first pressure value measured by the first pressure measurement module to the controller; at the moment, the second pressure measuring module does not collect the second pressure value, and an alarm is sent out on an instrument panel or/and a central control screen when the automobile runs;

if the first pressure value measured by the first pressure measurement module is larger than a preset first pressure threshold value, the first pressure measurement module continues to measure the first pressure value in the fuel tank; step S12 is executed;

s12, the controller receives the first pressure value and the second pressure value sent by the second pressure measurement module; the controller judges whether the first pressure value is larger than or equal to a preset second pressure threshold value:

if the first pressure value is greater than or equal to a preset second pressure threshold value, and the preset second pressure threshold value is greater than the preset first pressure threshold value, calculating the liquid level height, wherein the liquid level height calculation method comprises the following steps:

s121, calculating the liquid level height measured by the first pressure measurement module:

F₁＝ηρgh₁S₁

wherein, F₁Representing a first pressure value measured by a first pressure measurement module;

ρ represents the fuel density in the fuel tank;

g represents the acceleration of gravity, generally 9.8N/Kg, N represents the mechanical unit of cattle, and Kg represents the unit of mass of kilogram;

h₁indicating a distance of the first pressure measurement module from a fuel level;

S₁representing a force-bearing area of the first pressure measurement module;

η represents a conversion coefficient;

H₁＝h₁+h₁′，

wherein h is₁Representing the height value of the first pressure measurement module from the fuel liquid level;

h₁' denotes the distance of the first pressure measuring module from the bottom of the fuel tank;

H₁indicating the liquid level height measured by the first pressure measurement module;

s122, calculating the liquid level height measured by the second pressure measurement module:

F₂＝ηρgh₂S₂

wherein, F₂Representing a second pressure value measured by a second pressure measurement module;

ρ represents the fuel density in the fuel tank;

g represents the acceleration of gravity, generally 9.8N/Kg, N represents the mechanical unit of cattle, and Kg represents the unit of mass of kilogram;

h₂to representThe distance between the second pressure measurement module and the fuel liquid level;

S₂representing the force-bearing area of the second pressure measurement module;

η represents a conversion coefficient;

H₂＝h₂+h₂′，

wherein h is₂The height value of the second pressure measurement module from the fuel liquid surface is represented;

h₂' denotes the distance of the second pressure measuring module from the bottom of the fuel tank;

H₂indicating the liquid level height measured by the second pressure measurement module;

s123, judging the liquid level height H measured by the first pressure measurement module₁And the liquid level height H measured by the second pressure measurement module₂The relationship between:

if it is

The absolute value is represented by | l, the preset height difference error threshold value is represented by Δ H, and the height difference between the first pressure measurement module and the second pressure measurement module is represented by Δ H;H₀if the intermediate parameter is indicated, step S124 is executed;

if it isStep S125 is executed;

h represents the liquid level height of the automobile when the automobile is not started, wherein the liquid level height is obtained according to a first pressure value measured by the first pressure measuring module and a second pressure value measured by the second pressure measuring module;

where min (,) represents the smaller of them.

In a preferred embodiment of the present invention, step S2 includes the following steps:

s21, obtaining the real-time flow value measured by the flow sensor when the automobile runs, and recording the value as Q_t；

S22, calculating the fuel consumption volume of the automobile before the T moment, wherein the calculation method of the fuel consumption volume comprises the following steps:

wherein Q is_tRepresenting the real-time flow value at the time t;

representing an error coefficient;

V_Trepresenting the volume of fuel consumed by the automobile before T moment;

s23, rootVolume of consumed fuel V before time T calculated according to step S22_TAnd calculating the fuel tank descending height value, wherein the calculation method of the fuel tank descending height value comprises the following steps:

h＝V_T/s，

wherein, V_TRepresenting the volume of fuel consumed by the automobile before T moment;

s represents a cross-sectional area of the fuel tank;

h represents a fuel tank descent height value;

s24, calculating the liquid level height of the fuel tank according to the fuel tank descending height value h calculated in the step S23, wherein the calculation method of the liquid level height of the fuel tank comprises the following steps:

H₀＝H-h，

h represents the liquid level height of the automobile when the automobile is not started, wherein the liquid level height is obtained according to a first pressure value measured by the first pressure measuring module and a second pressure value measured by the second pressure measuring module;

h represents a fuel tank descent height value;

H₀which represents the level of the fuel tank when the vehicle is running.

In a preferred embodiment of the present invention, step S2 further includes:

level height H of a fuel tank during operation of a motor vehicle₀And if the liquid level is less than or equal to the preset liquid level height threshold, an alarm is given out on an instrument panel or/and a central control screen.

In a preferred embodiment of the present invention, step S2 further includes:

level height H of a fuel tank during operation of a motor vehicle₀And if the preset first liquid level height threshold is smaller than or equal to the preset first liquid level height threshold, the controller sends a control signal, and the control signal is an automobile stop signal to stop the automobile from running.

In a preferred embodiment of the invention, the automatic fuel filling system further comprises a fuel filling identification module arranged on the inner side of the automobile fuel tank door, so that automatic fuel filling of an automobile is realized.

In conclusion, due to the adoption of the technical scheme, the liquid level in the fuel tank can be measured and displayed, so that a driver can know the condition of the fuel tank in real time conveniently, and the experience of the driver is enhanced.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic block diagram of the connection of the present invention.

Fig. 2 is a schematic diagram of the connection of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

The invention discloses a fuel liquid level sensing system based on differential pressure, which comprises a fuel pump 6 arranged in a fuel tank 3, and further comprises a first pressure measurement module and a second pressure measurement module (the first pressure measurement module and the second pressure measurement module are not shown in the figure) arranged on the fuel pump 6, as shown in figure 1, the pressure data output end of the first pressure measurement module is connected with the first pressure data input end of the second pressure measurement module, the first pressure measurement module is used for measuring a first pressure value in the fuel tank 3 and transmitting the measured first pressure value to the second pressure measurement module, the pressure data output end of the second pressure measurement module is connected with the pressure data input end of a controller through a data wire 2, the second pressure measurement module is used for measuring a second pressure value in the fuel tank 3, transmitting the measured second pressure value and the first pressure value measured by the first pressure measurement module and received by the second pressure measurement module to a controller, wherein a display end of a dashboard of the controller is connected with a display end of the dashboard, a display end of a central control screen of the controller is connected with a display end of the central control screen, the first pressure measurement module and the second pressure measurement module have different measurement heights, and the distance from the second pressure measurement module to the bottom of the fuel tank 3 is less than the distance from the first pressure measurement module to the bottom of the fuel tank 3; preferably, the first pressure measuring module is arranged on the periphery of the fuel pump 6, and the second pressure measuring module is arranged at the bottom of the fuel pump 6.

The controller calculates the liquid level height of the fuel tank 3 according to the received pressure data, displays the liquid level height on an instrument panel or/and a central control screen, and gives an alarm on the instrument panel or/and the central control screen when the liquid level height of the fuel tank 3 is smaller than or equal to a preset liquid level height threshold value.

In a preferred embodiment of the invention, the fuel pump control system further comprises a flow sensor arranged on the fuel conveying pipeline 4 of the fuel pump 6 and used for measuring the fuel quantity sprayed to the engine by the fuel pump 6, and the flow data output end of the flow sensor is connected with the flow data input end of the controller.

In a preferred embodiment of the present invention, as shown in fig. 2, a fuel tank 5 is further provided in the fuel tank 3, a fuel pump 6 is provided in the fuel tank 5, a fuel filter hole is provided at the bottom of the fuel tank 5, a fuel screen 8 for filtering fuel impurities in the fuel tank 3 is provided on the fuel filter hole, M vent holes 1 which are spatially communicated with the fuel tank 3 are provided at the upper end of the tank body of the fuel tank 5, and M is a positive integer greater than or equal to 1; in the present embodiment, two vent holes 1, the 1 st vent hole and the 2 nd vent hole, are provided. The secondary filtration of the fuel in the fuel tank 3 is realized, and the oil quality is improved.

The oil filter is characterized in that a three-way pipe 7 is arranged in the oil filter tank 5, a first port of the three-way pipe 7 is connected with an oil filter hole, a second port of the three-way pipe 7 is connected with an exhaust hole of the fuel pump 6, and a third port of the three-way pipe 7 is not connected and is opened to the inner space of the oil filter tank 5. When the exhaust hole discharges fuel oil or air (the air in the fuel pump 3 is discharged at the beginning of the starting of the fuel pump 6, and the exhaust port continuously discharges a small amount of fuel oil during normal work after the air is discharged), the fluid flows through the three-way pipe from the horizontal direction, the fuel oil in the fuel tank 3 is sucked by the first port of the three-way pipe and is discharged into the oil filter tank 5 by the third port of the three-way pipe according to the Bernoulli principle, even if the fuel oil level in the fuel tank 3 is low, the oil filter tank 5 can keep the determined fuel oil level, and the fuel pump 6 can conveniently absorb the fuel oil.

In a preferred embodiment of the present invention, further comprising a mounting structure for varying a distance between the first pressure measuring module and a bottom of the fuel tank 3, the mounting structure comprising:

two groups of mounting and fixing side plates which are vertically arranged on the periphery of the fuel pump 6 and between which the first pressure measurement module fixing mounting seat can be embedded are uniformly distributed, and a plurality of groups of mounting holes are uniformly distributed on the mounting and fixing side plates;

the first pressure measurement module is detachably mounted on the first pressure measurement module fixed mounting seat, and adjusting claws detachably mounted with the mounting holes are arranged on two sides of the first pressure measurement module fixed mounting seat;

the first pressure measurement module fixing mounting seat is detachably mounted with the mounting hole through the adjusting claw. The structure is convenient for adjusting the distance between the first pressure measuring module and the bottom of the fuel tank, and further adjusting the height value between the first pressure measuring module and the second pressure measuring module.

In a preferred embodiment of the present invention, the mounting hole is provided with a slip-off preventing surface inclined outward, the adjusting grip is provided with a grip surface capable of coming into contact with the slip-off preventing surface, and the grip surface is inclined outward of the mounting hole. The mounting hole and the adjusting claw are convenient to mount stably and prevent falling.

The invention also discloses a control method of the fuel liquid level sensing and sensing system based on differential pressure, which comprises the following steps:

s1, when the automobile is not started, measuring the liquid level height of the fuel tank 3;

s2, when the vehicle is running, the liquid level of the fuel tank 3 is measured and displayed on the instrument panel or/and the central control panel.

In a preferred embodiment of the present invention, step S1 includes the following steps:

s11, the second pressure measurement module determines whether the first pressure value measured by the first pressure measurement module is less than or equal to a preset first pressure threshold:

if the first pressure value measured by the first pressure measurement module is smaller than or equal to a preset first pressure threshold value, the second pressure measurement module transmits the first pressure value measured by the first pressure measurement module to the controller; at the moment, the second pressure measuring module does not collect the second pressure value, and an alarm is sent out on an instrument panel or/and a central control screen when the automobile runs;

if the first pressure value measured by the first pressure measurement module is greater than the preset first pressure threshold, the first pressure measurement module continues to measure the first pressure value in the fuel tank 3; step S12 is executed;

s12, the controller receives the first pressure value and the second pressure value sent by the second pressure measurement module; the controller judges whether the first pressure value is larger than or equal to a preset second pressure threshold value:

if the first pressure value is greater than or equal to a preset second pressure threshold value, and the preset second pressure threshold value is greater than the preset first pressure threshold value, calculating the liquid level height, wherein the liquid level height calculation method comprises the following steps:

s121, calculating the liquid level height measured by the first pressure measurement module:

F₁＝ηρgh₁S₁

wherein, F₁Representing a first pressure value measured by a first pressure measurement module;

ρ represents the fuel density in the fuel tank 3;

g represents the acceleration of gravity, generally 9.8N/Kg, N represents the mechanical unit of cattle, and Kg represents the unit of mass of kilogram;

h₁indicating a distance of the first pressure measurement module from a fuel level;

S₁representing a force-bearing area of the first pressure measurement module;

η represents a conversion coefficient;

H₁＝h₁+h₁′，

wherein h is₁Representing the height value of the first pressure measurement module from the fuel liquid level;

h₁' denotes the distance of the first pressure measuring module from the bottom of the fuel tank 3;

H₁indicating the liquid level height measured by the first pressure measurement module;

s122, calculating the liquid level height measured by the second pressure measurement module:

F₂＝ηρgh₂S₂

wherein, F₂Representing a second pressure value measured by a second pressure measurement module;

ρ represents the fuel density in the fuel tank 3;

g represents the acceleration of gravity, generally 9.8N/Kg, N represents the mechanical unit of cattle, and Kg represents the unit of mass of kilogram;

h₂indicating the distance of the second pressure measurement module from the fuel level;

S₂representing the force-bearing area of the second pressure measurement module;

η represents a conversion coefficient;

H₂＝h₂+h₂′，

wherein h is₂The height value of the second pressure measurement module from the fuel liquid surface is represented;

h₂' denotes the distance of the second pressure measuring module from the bottom of the fuel tank 3;

H₂indicating the liquid level height measured by the second pressure measurement module;

s123, judging the liquid level height H measured by the first pressure measurement module₁And the liquid level height H measured by the second pressure measurement module₂The relationship between:

if it is

The absolute value is represented by | l, the preset height difference error threshold value is represented by Δ H, and the height difference between the first pressure measurement module and the second pressure measurement module is represented by Δ H;H₀if the intermediate parameter is indicated, step S124 is executed;

if it isStep S125 is executed;

h represents the liquid level height of the automobile when the automobile is not started, wherein the liquid level height is obtained according to a first pressure value measured by the first pressure measuring module and a second pressure value measured by the second pressure measuring module;

where min (,) represents the smaller of them.

In a preferred embodiment of the present invention, step S2 includes the following steps:

s21, obtaining the real-time flow value measured by the flow sensor when the automobile runs, and recording the value as Q_t；

S22, calculating the fuel consumption volume of the automobile before the T moment, wherein the calculation method of the fuel consumption volume comprises the following steps:

wherein Q is_tRepresenting the real-time flow value at the time t;

representing an error coefficient;

V_Trepresenting the volume of fuel consumed by the automobile before T moment;

s23, according to the volume V of consumed fuel before T time calculated in the step S22_TAnd calculating the descending height value of the fuel tank 3, wherein the descending height value of the fuel tank 3 is calculated by the following method:

h＝V_T/s，

wherein, V_TRepresenting the volume of fuel consumed by the automobile before T moment;

s represents the cross-sectional area of the fuel tank 3;

h represents a fuel tank 3 descent height value;

s24, calculating the liquid level height of the fuel tank 3 according to the descending height value h of the fuel tank 3 calculated in the step S23, wherein the calculation method of the liquid level height of the fuel tank 3 is as follows:

H₀＝H-h，

h represents the liquid level height of the automobile when the automobile is not started, wherein the liquid level height is obtained according to a first pressure value measured by the first pressure measuring module and a second pressure value measured by the second pressure measuring module;

h represents a fuel tank 3 descent height value;

H₀which represents the level of the fuel tank 3 when the vehicle is running.

In a preferred embodiment of the present invention, step S2 further includes:

the level height H of the fuel tank 3 when the motor vehicle is running₀And if the liquid level is less than or equal to the preset liquid level height threshold, an alarm is given out on an instrument panel or/and a central control screen.

In a preferred embodiment of the present invention, step S2 further includes:

the level height H of the fuel tank 3 when the motor vehicle is running₀And if the preset first liquid level height threshold is smaller than or equal to the preset first liquid level height threshold, the controller sends a control signal, and the control signal is an automobile stop signal to stop the automobile from running.

In a preferred embodiment of the present invention, a refueling identification module (i.e. a radio frequency tag) is further disposed inside the fuel tank door of the vehicle, so as to automatically refuel the vehicle. This refuel the storage of identification module and have user information, this user information includes user's name and ID card number, inserts the tank filler sleeve back as its nozzle, is provided with the acquisition module that is used for discerning to refuel identification module and stores user information on the nozzle, and the acquisition module is according to the user information who acquires, and the automatic settlement refuels amount of money, need not the car owner and get off payment cash, and is swift convenient.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.