CN-121976871-A - Method and device for determining fault type of air-driven urea system in vehicle and vehicle

CN121976871ACN 121976871 ACN121976871 ACN 121976871ACN-121976871-A

Abstract

The application discloses a fault type determining method and device of an air-driven urea system in a vehicle and the vehicle. The method comprises the steps of responding to a first working state of the gas-driven urea system, controlling the collection equipment to collect the first pressure born by the urea tank actually, calibrating the collection equipment to obtain the calibrated collection equipment in response to the pressure difference between the first pressure and the target pressure being greater than or equal to a pressure threshold value, controlling the state of the gas-driven urea system to be switched from the first working state to a second working state, controlling the calibrated collection equipment to collect the second pressure of the urea nozzle in the second working state, and determining the fault type of the gas-driven urea system based on the second pressure and the duty ratio of the urea nozzle. The application solves the technical problem of low fault determination accuracy of the urea system of the vehicle.

Inventors

LONG YUAN
Hua Taodie
ZHANG CONG
GAO SHANSHAN

Assignees

一汽解放汽车有限公司

Dates

Publication Date: 20260505
Application Date: 20260306

Claims (14)

1. A method of determining a fault type of an air-driven urea system in a vehicle, the air-driven urea system comprising a plurality of urea nozzles, a urea tank, and a collection device, the method comprising: Controlling the collection equipment to collect the actual first pressure born by the urea tank in response to the gas-driven urea system being in a first working state, wherein the first working state is used for indicating the state that urea in the urea tank flows to a plurality of urea nozzles, a target pressure acts on the urea tank, and urea in the urea tank flows to a plurality of urea nozzles through the target pressure; Calibrating the acquisition equipment in response to the pressure difference between the first pressure and the target pressure being greater than or equal to a pressure threshold value, so as to obtain calibrated acquisition equipment, wherein the pressure difference between the first pressure acquired by the calibrated acquisition equipment and the target pressure is smaller than the pressure threshold value; controlling the state of the gas-driven urea system to be switched from the first working state to a second working state, and controlling the calibrated collecting equipment to collect second pressure of the urea nozzles in the second working state, wherein the second working state is an injection state of alternately injecting the urea into the gas discharged by the vehicle by utilizing a plurality of urea nozzles, and the second pressure is used for representing the pressure applied by the urea nozzles for injecting the urea; Based on the second pressure, and a duty cycle of the urea nozzle, a fault type of the gas-driven urea system is determined.
2. The method of claim 1, wherein the collection device comprises a first collection device and a second collection device, the first collection device collects the medium in a pressure state as a liquid, the second collection device collects the medium in a pressure state as a gas, and the calibration of the collection device in response to the pressure difference between the first pressure and the target pressure being greater than or equal to a pressure threshold value results in a calibrated collection device comprising: In response to the pressure difference between the first pressure and the target pressure being greater than or equal to a pressure threshold, in the first working state, controlling the gas-driven urea system to perform pressure maintaining operation within a first preset time period, and acquiring a first pressure average value acquired by the first acquisition equipment and a second pressure average value acquired by the second acquisition equipment in the process of performing the pressure maintaining operation; In the first working state, controlling a urea nozzle in the urea nozzles, executing injection operation within a second preset time period, and acquiring a third pressure average value acquired by the first acquisition equipment and a fourth pressure average value acquired by the second acquisition equipment in the process of executing the injection operation; Determining a calibration coefficient of the acquisition device by using the first pressure average value, the second pressure average value, the third pressure average value and the fourth pressure average value; and calibrating the acquisition equipment by using the calibration coefficient to obtain the calibrated acquisition equipment.
3. The method of claim 2, wherein the first pressure comprises a liquid circuit pressure and a gas circuit pressure, and determining the calibration coefficients of the acquisition device using the first pressure average, the second pressure average, the third pressure average, and the fourth pressure average comprises: Determining an average pressure of both the first pressure average and the third pressure average; determining a half of the average pressure as a correction amount of the acquisition device; Determining a maximum value between the hydraulic circuit pressure and the gas circuit pressure, and determining a difference between the maximum value and the correction amount; Determining a minimum value between the hydraulic circuit pressure and the gas circuit pressure, and determining a sum between the minimum value and the correction amount; the calibration coefficients are determined based on the difference and the sum.
4. The method of claim 2, wherein calibrating the acquisition device using the calibration coefficients results in a calibrated acquisition device, comprising: and responding to the calibration coefficient being smaller than or equal to a calibration coefficient threshold value, and calibrating the acquisition equipment by using the calibration coefficient to obtain the calibrated acquisition equipment.
5. The method according to claim 4, wherein the method further comprises: And determining that the acquisition device is in a fault state in response to the calibration coefficient being greater than the calibration coefficient threshold.
6. The method of claim 1, wherein determining the type of fault of the gas-driven urea system based on the second pressure and the duty cycle of the urea nozzle comprises: Detecting the gas-driven urea system based on the second pressure and the duty ratio to obtain a detection result; and determining the fault type based on the second pressure in response to the detection result being that the gas-driven urea system is in a fault state.
7. The method of claim 6, wherein the second pressure comprises a maximum pressure, a minimum pressure, and an intermediate pressure, the intermediate pressure being an average of the maximum pressure and the minimum pressure, and wherein detecting the gas-driven urea system based on the second pressure and the duty cycle results in a detection result comprising: Determining a first difference between the maximum pressure and the intermediate pressure in the same injection period and a second difference between the intermediate pressure and the minimum pressure in the same injection period in response to the duty cycle being in a preset duty cycle interval; determining a first difference average value of the first differences in a preset number of the injection periods, and determining a second difference average value of the second differences in the preset number of the injection periods; determining a third difference between the first difference average and a self-learned value of the gas-driven urea system, and determining a fourth difference between the second difference average and the self-learned value, wherein the self-learned value is used for representing a desired degree of pressure fluctuation in the gas-driven urea system; And in response to the third difference being greater than a first threshold and/or the fourth difference being greater than the first threshold, determining that the detection result is that the gas-driven urea system is in the fault state.
8. The method of claim 7, wherein the gas-driven urea system includes an intake valve and a selective catalytic reduction system, the method further comprising: Controlling the air inlet valve to be in an open state in response to the detection result that the air-driven urea system is in a fault state and the third difference value is larger than the first threshold value and/or the fourth difference value is larger than the first threshold value; Recalculating the third and fourth differences in response to the first pressure in the urea tank being increased with the intake valve in the open state; In response to the recalculated third difference being greater than a second threshold and/or the fourth difference being greater than a second threshold, determining a conversion efficiency of the selective catalytic reduction system.
9. The method of claim 8, wherein the fault type comprises a urea nozzle fault, and wherein determining the fault type based on the second pressure in response to the detection result being that the gas-driven urea system is in a fault state comprises: and responding to the detection result that the gas-driven urea system is in a fault state, wherein the conversion efficiency is smaller than a conversion efficiency threshold value, and determining that the fault type is the urea nozzle fault.
10. The method of claim 8, wherein the plurality of urea nozzles comprises a near-end nozzle and a far-end nozzle, wherein the urea nozzle failure comprises a near-end nozzle failure and a far-end nozzle failure, wherein responsive to the detection that the gas-driven urea system is in a failed state and the conversion efficiency is less than a conversion efficiency threshold, determining that the failure type is the urea nozzle failure comprises: responding to the detection result that the gas-driven urea system is in a fault state, wherein the conversion efficiency is smaller than the conversion efficiency threshold value, the third difference value is larger than a second threshold value, and the fault type is determined to be the remote nozzle fault; And responding to the detection result that the gas-driven urea system is in a fault state, wherein the conversion efficiency is smaller than the conversion efficiency threshold value, the fourth difference value is larger than a second threshold value, and the fault type is determined to be the near-end nozzle fault.
11. The method of claim 7, wherein the fault type comprises a urea filter cartridge fault, and wherein determining the fault type based on the second pressure in response to the detection result being that the gas-driven urea system is in a fault state comprises: determining a pressure difference between the first pressure and the intermediate pressure in response to the detection result being that the gas-driven urea system is in a fault state; and determining that the fault type is the urea filter fault in response to the pressure differential being greater than a third threshold.
12. A fault type determination apparatus for an air-driven urea system in a vehicle, the air-driven urea system including a plurality of urea nozzles, a urea tank, and a collection device, the apparatus comprising: the first control unit is used for responding to the first working state of the gas-driven urea system, and controlling the acquisition equipment to acquire the actual first pressure born by the urea tank, wherein the first working state is used for indicating the state that urea in the urea tank flows to a plurality of urea nozzles, the urea tank is acted with target pressure, and urea in the urea tank flows to a plurality of urea nozzles through the target pressure; The calibration unit is used for calibrating the acquisition equipment to obtain calibrated acquisition equipment in response to the fact that the pressure difference between the first pressure and the target pressure is larger than or equal to a pressure threshold value, wherein the pressure difference between the first pressure acquired by the calibrated acquisition equipment and the target pressure is smaller than the pressure threshold value; the second control unit is used for controlling the state of the gas-driven urea system to be switched from the first working state to a second working state, and controlling the calibrated collecting equipment to collect second pressure of the urea nozzles in the second working state, wherein the second working state is an injection state of alternately injecting the urea into the gas discharged by the vehicle by utilizing a plurality of urea nozzles, and the second pressure is used for representing the pressure applied by the urea nozzles for injecting the urea; And the determining unit is used for determining the fault type of the gas-driven urea system based on the second pressure and the duty ratio of the urea nozzle.
13. A vehicle, characterized by comprising: a memory storing an executable program; A processor for executing the program, wherein the program when run performs the method of any of claims 1 to 11.
14. An electronic device, comprising: a memory storing an executable program; A processor for executing the program, wherein the program when run performs the method of any of claims 1 to 11.

Description

Method and device for determining fault type of air-driven urea system in vehicle and vehicle Technical Field The application relates to the field of vehicles, in particular to a fault type determining method and device of an air-driven urea system in a vehicle and the vehicle. Background Currently, a fault type determining method of a urea system in a vehicle mainly monitors pressure changes of a urea nozzle through a single sensor so as to determine the fault type of the urea system. However, when the fault type of the urea system is determined by the method, faults of multiple devices in the urea system cannot be distinguished, and the identification result of the fault type is easily affected by device aging and sensor offset. Therefore, there still exists a technical problem that the failure determination accuracy of the urea system of the vehicle is low. In view of the above technical problems, no effective solution has been proposed at present. Disclosure of Invention The embodiment of the application provides a method and a device for determining the fault type of an air-driven urea system in a vehicle and the vehicle, and aims to at least solve the technical problem of low accuracy of fault determination of the vehicle urea system. According to one aspect of an embodiment of the present application, a method for determining a fault type of a gas-driven urea system in a vehicle is provided. The air-driven urea system comprises a plurality of urea nozzles, a urea tank and a collecting device, and the method can comprise the steps of responding to the air-driven urea system to be in a first working state, controlling the collecting device to collect the first actual pressure born by the urea tank, wherein the first working state is used for indicating the state that urea in the urea tank flows to the plurality of urea nozzles, the urea tank is acted with target pressure, urea in the urea tank flows to the plurality of urea nozzles through the target pressure, calibrating the collecting device to obtain the calibrated collecting device according to the fact that the pressure difference between the first pressure and the target pressure is larger than or equal to a pressure threshold, utilizing the first pressure collected by the calibrated collecting device to be smaller than the pressure threshold, controlling the air-driven urea system to switch from the first working state to the second working state, and controlling the calibrated collecting device to collect the second pressure of the urea nozzles in the second working state, wherein the second working state is used for alternately spraying urea into gas discharged by a vehicle through the plurality of urea nozzles, the second pressure is used for indicating the spraying urea nozzles, and the second pressure applied by the collecting device is used for determining the urea spraying pressure and the urea system based on the fault type. Optionally, the collecting device comprises a first collecting device and a second collecting device, the medium in the pressure state is liquid, the medium in the pressure state is gas, the collecting device is calibrated in response to the pressure difference between the first pressure and the target pressure being greater than or equal to a pressure difference threshold, the calibrated collecting device comprises a step of controlling the gas-driven urea system to execute pressure maintaining operation within a first preset time period in a first working state, and in the process of executing the pressure maintaining operation, obtaining a first pressure average value collected by the first collecting device and a second pressure average value collected by the second collecting device, in the first working state, controlling a urea nozzle in a plurality of urea nozzles, in the second preset time period, executing injection operation, and in the process of executing the injection operation, obtaining a third pressure average value collected by the first collecting device and a fourth pressure average value collected by the second collecting device, in the first working state, controlling the gas-driven urea system to execute pressure maintaining operation within a first preset time period, and in the process of executing the injection operation, determining the collecting device to calibrate the collecting device by using the first pressure average value, the collecting device, and the calibrating device. Optionally, the first pressure comprises a liquid path pressure and a gas path pressure, and the first pressure average value, the second pressure average value, the third pressure average value and the fourth pressure average value are utilized to determine a calibration coefficient of the acquisition device, wherein the calibration coefficient comprises the steps of determining the average pressure of the first pressure average value and the third pressure average value, determining half of the average pressure