A range extended electric vehicle cng inventory display system and method

Abstract

The application discloses a kind of range-extended electric vehicle CNG inventory display system and method, method steps are as follows: S1: calculate pressure: system sampling pressure sensor voltage, sensor voltage is filtered, and real-time cylinder pressure is obtained;S2: correction pressure: cylinder pressure is corrected by ambient temperature and target state temperature;S3: calculate table pressure: according to ambient temperature, calculate table full gas pressure threshold value.The system includes pressure calculation module, pressure correction module, table pressure calculation module, curve table lookup module.The application solves the problem that table pressure changes with gas temperature in bottle, ambient temperature, reduces misunderstanding of user to gas leakage, gas consumption and the like.

Description

Technical Field

[0001] This invention relates to the field of automotive powertrain control, and more particularly to a CNG inventory display system and method for range-extended electric vehicles. Background Technology

[0002] In the current technology, CNG range-extended electric vehicles represent the current fuel quantity by the actual pressure of the gas inside the cylinder. The actual measured pressure inside the cylinder is displayed on the instrument panel. However, this method of displaying pressure has the following problems:

[0003] 1. The current displayed cylinder pressure is the actual pressure. At a normal temperature of 15℃, the cylinder temperature after filling is about 60-70℃. After the cylinder temperature drops to the ambient temperature of 15℃, the displayed pressure will decrease. Seeing the pressure drop will be mistaken for a gas leak.

[0004] 2. CNG range-extended electric vehicles are used in areas with large temperature differences between day and night. When the ambient temperature drops suddenly while the vehicle is not in use, the pressure in the gas cylinder will also decrease. Seeing the pressure drop may be mistaken for a leak or an inaccurate pressure gauge. Summary of the Invention

[0005] The purpose of this invention is to address the aforementioned technical problems by providing a CNG inventory display system and method for range-extended electric vehicles.

[0006] A method for displaying CNG inventory in a range-extended electric vehicle, comprising the following steps:

[0007] S1: Calculate pressure: The system samples the voltage of the pressure sensor, filters the sensor voltage, and obtains the real-time cylinder pressure;

[0008] S2: Correction pressure: Corrects the cylinder pressure based on ambient temperature and target temperature;

[0009] S3: Calculate the displayed pressure: Calculate the full-volume pressure threshold based on the ambient temperature.

[0010] Furthermore, a method for displaying the CNG stock of a range-extended electric vehicle, wherein step S1 includes the following sub-steps:

[0011] S11: The system samples the voltage of the pressure sensor. Assuming the sampling period is t milliseconds, the sensor voltage is calculated using the following formula:

[0012]

[0013] Where U1 represents the sensor voltage, B1 represents the return value of the sampling module, U2 represents the reference voltage, and B2 represents the number of bits in the sampling module;

[0014] S12: The sensor voltage is filtered using a first-order low-pass filter, with the following formula:

[0015]

[0016] Where G(s) represents the transfer function, s represents the frequency-related variable parameter, Ts represents the time parameter, and T represents the filter time constant;

[0017] S13: Input the filtered sensor voltage into the curve lookup module, and obtain the real-time gas cylinder pressure by querying the curve lookup module.

[0018] Furthermore, in a method for displaying the CNG stock of a range-extended electric vehicle, step S2 includes the following sub-steps:

[0019] S21: The system obtains the target state temperature from the curve lookup table module by using the ambient temperature;

[0020] S22: Correct the real-time cylinder pressure using a pressure correction factor. The formula is as follows:

[0021]

[0022] Where N2 represents the corrected cylinder pressure, N1 represents the real-time cylinder pressure, K1 represents the ambient temperature, and K2 represents the target temperature. This represents the pressure correction factor.

[0023] Furthermore, in a method for displaying the CNG inventory of a range-extended electric vehicle, step S3 includes the following sub-steps:

[0024] S31: The system obtains the full air pressure threshold displayed by looking up the table in the curve using the ambient temperature.

[0025] S32: Determine whether to display the corrected cylinder pressure based on the full-volume pressure threshold N3:

[0026] If N2 > N3, then the full air pressure threshold N3 will be displayed.

[0027] If N2 <= N3, then the corrected cylinder pressure N2 will be displayed.

[0028] A CNG inventory display system for range-extended electric vehicles includes a pressure calculation module, a pressure correction module, a display pressure calculation module, and a curve lookup table module.

[0029] The pressure calculation module obtains the real-time cylinder pressure;

[0030] The pressure correction module obtains the corrected cylinder pressure;

[0031] The cylinder pressure calculation module corrects the displayed pressure.

[0032] The curve lookup table module stores the data and performs the lookup to convert voltage to air pressure.

[0033] Furthermore, a CNG stock display system for range-extended electric vehicles includes a pressure calculation module comprising a sampling module and a filtering module.

[0034] The sampling module samples the voltage of the pressure sensor;

[0035] The filtering module is implemented by a first-order low-pass filter.

[0036] Furthermore, in a CNG stock display system for range-extended electric vehicles, the pressure calculation module further includes a device pressure sensor and a first-order low-pass filter.

[0037] The beneficial effects of this invention are as follows: By implementing a CNG inventory display system and method for range-extended electric vehicles, the system calculates the sensor voltage, the actual cylinder voltage, and the corrected cylinder voltage through a pressure sensor and a first-order low-pass filter. Finally, it determines whether to display the corrected cylinder voltage based on a threshold value. This solves the problem of the displayed pressure changing with the temperature of the gas inside the cylinder and the ambient temperature, and reduces user misunderstandings about gas leaks and high gas consumption. Attached Figure Description

[0038] Figure 1 This is a framework diagram of the system of the present invention.

[0039] Figure 2 This is a flowchart of method S1 of the present invention.

[0040] Figure 3 This is a flowchart of method S2 of the present invention.

[0041] Figure 4 This is a flowchart of method S3 of the present invention. Detailed Implementation

[0042] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0043] As attached Figure 1 As shown, a CNG inventory display system for range-extended electric vehicles includes a pressure calculation module, a pressure correction module, a display pressure calculation module, and a curve lookup table module.

[0044] The pressure calculation module obtains the real-time cylinder pressure;

[0045] The pressure correction module obtains the corrected cylinder pressure;

[0046] The cylinder pressure calculation module corrects the displayed pressure.

[0047] The curve lookup table module stores the data and performs the lookup to convert voltage to air pressure.

[0048] Furthermore, a CNG stock display system for range-extended electric vehicles includes a pressure calculation module comprising a sampling module and a filtering module.

[0049] The sampling module samples the voltage of the pressure sensor;

[0050] The filtering module is implemented by a first-order low-pass filter.

[0051] Furthermore, in a CNG stock display system for range-extended electric vehicles, the pressure calculation module further includes a device pressure sensor and a first-order low-pass filter.

[0052] A method for displaying CNG inventory in a range-extended electric vehicle, comprising the following steps:

[0053] S1: Calculate pressure: The system samples the voltage of the pressure sensor, filters the sensor voltage, and obtains the real-time cylinder pressure;

[0054] S2: Correction pressure: Corrects the cylinder pressure based on ambient temperature and target temperature;

[0055] S3: Calculate the displayed pressure: Calculate the full-volume pressure threshold based on the ambient temperature.

[0056] As attached Figure 2 As shown, a method for displaying CNG inventory in a range-extended electric vehicle, wherein step S1 includes the following sub-steps:

[0057] S11: The system samples the voltage of the pressure sensor. Assuming the sampling period is t milliseconds, the sensor voltage is calculated using the following formula:

[0058]

[0059] Where G(s) represents the transfer function, s represents the frequency-related variable parameter, Ts represents the time parameter, and T represents the filter time constant;

[0060] S12: The sensor voltage is filtered using a first-order low-pass filter, with the following formula:

[0061]

[0062] Where G(s) represents the transfer function, s represents the frequency-related variable parameter, Ts represents the time parameter, and T represents the filter time constant;

[0063] S13: Input the filtered sensor voltage into the curve lookup module, and obtain the real-time gas cylinder pressure by querying the curve lookup module.

[0064] The filtering time constant is a fixed value, allowing engineers to adjust the filtering time according to actual conditions to obtain a high-quality voltage signal.

[0065] As attached Figure 3 As shown, a method for displaying CNG inventory in a range-extended electric vehicle, wherein step S2 includes the following sub-steps:

[0066] S21: The system obtains the target state temperature from the curve lookup table module by using the ambient temperature;

[0067] S21: Correct the real-time cylinder pressure using a pressure correction factor. The formula is as follows:

[0068]

[0069] Where N2 represents the corrected cylinder pressure, N1 represents the real-time cylinder pressure, K1 represents the ambient temperature, and K2 represents the target temperature. This represents the pressure correction factor.

[0070] As attached Figure 4 As shown, a method for displaying CNG inventory in a range-extended electric vehicle, wherein step S3 includes the following sub-steps:

[0071] S31: The system obtains the full air pressure threshold displayed by looking up the table in the curve using the ambient temperature.

[0072] S32: Determine whether to display the corrected cylinder pressure based on the full-volume pressure threshold N3:

[0073] If N2 > N3, then the full air pressure threshold N3 will be displayed.

[0074] If N2 <= N3, then the corrected cylinder pressure N2 will be displayed.

[0075] In a specific embodiment, the XZ curve table display of the curve lookup module is shown.

[0076] Table 1. XZ curves of the pressure calculation module

[0077] X Sensor voltage 1 Sensor voltage 2 …… Sensor voltage n Z Real-time pressure of gas cylinder 1 Real-time pressure of gas cylinder 2 …… Real-time pressure of gas cylinder n

[0078] Table 2 XZ curves of the pressure correction module

[0079]

[0080]

[0081] Table 3 shows the XZ curves of the pressure calculation module.

[0082] X Ambient temperature 1 Ambient temperature 2 …… Ambient temperature n Z Display full air volume threshold 1 Display full air volume threshold 2 …… Display full air volume threshold n

[0083] The target state is set as a standard value, and application engineers can set the target state temperature according to the needs of the target market.

[0084] This solution provides a CNG inventory display system and method for range-extended electric vehicles. Through the implementation of a pressure sensor and a first-order low-pass filter, it calculates the sensor voltage, the actual cylinder voltage, and the corrected cylinder voltage. Finally, it determines whether to display the corrected cylinder voltage based on a threshold value. This solution can solve the problem of the displayed pressure changing with the temperature of the gas inside the cylinder and the ambient temperature, and reduce user misunderstandings about gas leaks and high gas consumption.

[0085] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A method for displaying the CNG inventory of a range-extended electric vehicle, characterized in that, The steps are as follows: S1: Pressure Calculation: The system samples the pressure sensor voltage, filters the sensor voltage, and obtains the real-time cylinder pressure; step S1 includes the following sub-steps: S11: The system samples the voltage of the pressure sensor. Assuming the sampling period is t milliseconds, the sensor voltage is calculated using the following formula: in, Represents the sensor voltage. This represents the return value of the sampling module. Represents the reference voltage. Represents the number of bits in the sampling module; S12: The sensor voltage is filtered using a first-order low-pass filter, with the following formula: in, Represents the transfer function. T represents the frequency-related variable parameter. The time parameter represents the filter time constant; S13: Input the filtered sensor voltage into the curve lookup module, and obtain the real-time gas cylinder pressure by querying the curve lookup module; S2: Pressure Correction: The cylinder pressure is corrected using ambient temperature and target temperature; step S2 includes the following sub-steps: S21: The system obtains the target state temperature from the curve lookup table module by using the ambient temperature; S22: Correct the real-time cylinder pressure using a pressure correction factor. The formula is as follows: in, This represents the corrected cylinder pressure. Represents real-time cylinder pressure. Represents ambient temperature. Represents the target temperature. Represents the pressure correction factor; S3: Calculate the displayed pressure: Calculate the displayed full-volume pressure threshold based on the ambient temperature; step S3 includes the following sub-steps: S31: The system obtains the full air pressure threshold displayed by looking up the table in the curve using the ambient temperature. S32: Display full-volume pressure threshold Determine if the corrected cylinder pressure is displayed: like > The full air volume pressure threshold will then be displayed. ; like <= This will display the corrected cylinder pressure. .

2. A CNG inventory display system for range-extended electric vehicles, implemented based on the CNG inventory display method for range-extended electric vehicles as described in claim 1, characterized in that, Includes a pressure calculation module, a pressure correction module, a display pressure calculation module, and a curve lookup table module; The pressure calculation module obtains the real-time cylinder pressure; The pressure correction module obtains the corrected cylinder pressure; The pressure calculation module calculates the displayed pressure using the corrected cylinder pressure. The curve lookup table module stores the data and performs the lookup to convert voltage to air pressure.

3. The CNG inventory display system for range-extended electric vehicles according to claim 2, characterized in that, The pressure calculation module includes a pressure sensor, a first-order low-pass filter, a sampling module, and a filtering module. The sampling module samples the voltage of the pressure sensor; The filtering module is implemented by a first-order low-pass filter.

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