Fault detection method and device for urea injector, tail gas treatment system and vehicle

Abstract

The invention discloses a fault detection method and device for a urea injector, a tail gas treatment system and a vehicle. The fault detection method comprises the steps that the current working state of the urea injector is obtained; acquiring electric energy data of the ejector control loop; the fault state of the urea injector is determined according to the current working state and the electric energy data, by means of the method, the fault condition of the injector can be detected in time, so that the injection precision of the urea injector is improved, and the problem that nitrogen oxide in tail gas exceeds the standard due to the influence of the injection precision of the urea injector is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of urea injectors, and in particular to a fault detection method and device for a urea injector, an exhaust gas treatment system and a vehicle. Background Art

[0002] In the related art, the urea injector injects according to the urea demand value of the urea injector calculated by the engine controller to reduce nitrogen oxides in the exhaust gas. However, when the urea injector fails, the injection accuracy of the urea injector is affected, resulting in excessive nitrogen oxides in the exhaust gas. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a fault detection method for a urea injector, by which the fault of the injector can be detected in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0004] A second object of the present invention is to provide a fault detection device for a urea injector.

[0005] A third object of the present invention is to provide an exhaust gas treatment system.

[0006] A fourth object of the present invention is to provide a vehicle.

[0007] In order to solve the above problems, a first aspect of an embodiment of the present invention provides a urea injector fault detection method for an exhaust gas treatment system, wherein the exhaust gas treatment system comprises an injector control circuit, and the urea injector is arranged in the injector control circuit. The fault detection method comprises: obtaining a current working state of the urea injector; obtaining electric energy data of the injector control circuit; and determining a fault state of the urea injector according to the current working state and the electric energy data.

[0008] According to the fault detection method of the urea injector of the embodiment of the present invention, the fault state of the urea injector is monitored by the electric energy data of the injector control circuit according to different current working states of the urea injector, so that the fault condition of the injector can be detected in time under different working states, so as to promptly remind the user to repair the fault condition of the urea injector, thereby improving the injection accuracy of the urea injector and avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0009] In some embodiments, the injector control loop includes a voltage regulator for providing a constant voltage to the urea injector and a driver for collecting the electric energy data. Before obtaining the current working state of the urea injector, the fault detection method further includes: controlling the voltage regulator to start, and controlling the driver to start after a preset time.

[0010] In some embodiments, the electric energy data includes at least a positive electrode voltage of the urea injector, and determining a fault state of the urea injector according to the current working state and the electric energy data includes: determining that the current working state is an activated state; and determining the fault state of the urea injector according to the positive electrode voltage.

[0011] In some embodiments, determining the fault state of the urea injector according to the positive electrode voltage includes: if the positive electrode voltage is lower than a first preset threshold, determining that the fault state of the urea injector is a short circuit fault to ground; if the positive electrode voltage is higher than a second preset threshold, determining that the fault state of the urea injector is a short circuit fault to power supply; if the positive electrode voltage is higher than the first preset threshold and lower than the second preset threshold, determining that the positive electrode of the urea injector is in a normal state.

[0012] In some embodiments, the electric energy data includes at least a cathode voltage of the urea injector, and determining a fault state of the urea injector according to the current working state and the electric energy data includes: determining that the current working state is an activated state; and determining the fault state of the urea injector according to the cathode voltage.

[0013] In some embodiments, determining the fault state of the urea injector according to the negative electrode voltage includes: if the negative electrode voltage is lower than a first preset threshold, determining that the fault state of the urea injector is an open circuit fault; if the negative electrode voltage is higher than a second preset threshold, determining that the fault state of the urea injector is a short circuit fault to a power supply; if the negative electrode voltage is higher than the first preset threshold and lower than the second preset threshold, determining that the negative electrode of the urea injector is in a normal state.

[0014] In some embodiments, the injector control circuit includes a first resistor, a second resistor, a first switch and a second switch, the first resistor, the urea injector and the second resistor are connected in series in sequence, the first switch is connected in parallel with the first resistor, and the second switch is connected in parallel with the second resistor. The fault detection method also includes: receiving an injection control instruction, controlling the urea injector to enter an action state, wherein in the action state, the first switch and the second switch are controlled to be periodically closed.

[0015] In some embodiments, the electric energy data includes at least an operating current of the injector control circuit, and determining a fault state of the urea injector according to the current operating state and the electric energy data includes: determining that the current operating state is an action state; and determining the fault state of the urea injector according to the operating current.

[0016] In some embodiments, determining the fault state of the urea injector according to the operating current includes: if the operating current is higher than a preset current value, determining that the fault state of the urea injector is a positive-negative short circuit fault; if the operating current is lower than the preset current value, determining that the urea injector is in a normal state.

[0017] A second aspect of the present invention provides a urea injector fault detection device for an exhaust gas treatment system, wherein the exhaust gas treatment system comprises an injector control circuit, wherein the urea injector is arranged in the injector control circuit, and wherein the fault detection device comprises: a first acquisition module, for acquiring a current working state of the urea injector; a second acquisition module, for acquiring electric energy data of the injector control circuit; and a determination module, for determining a fault state of the urea injector according to the current working state and the electric energy data.

[0018] According to the fault detection device of the urea injector of the embodiment of the present invention, the determination module monitors the fault state of the urea injector through the electric energy data of the injector control circuit according to different current working states of the urea injector, so that the fault condition of the injector can be detected in time under different working states, so as to promptly remind the user to repair the fault condition of the urea injector, thereby improving the injection accuracy of the urea injector and avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0019] A third aspect of the present invention provides an exhaust gas treatment system, comprising: an injector control circuit; a urea injector, wherein the urea injector is arranged in the injector control circuit; and a controller, wherein the controller is connected to the injector control circuit and is used to execute the urea injector fault detection method described in the above embodiment.

[0020] According to the exhaust gas treatment system of the embodiment of the present invention, by executing the fault detection method of the urea injector of the above embodiment, the fault of the injector can be detected in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0021] In some embodiments, the injector control loop includes: a voltage regulator for providing a constant voltage to the urea injector; and a driver for collecting the electric energy data.

[0022] In some embodiments, the injector control circuit includes: a first resistor, a second resistor, a first switch and a second switch, the first resistor, the urea injector and the second resistor are connected in series in sequence, the first switch is connected in parallel with the first resistor, and the second switch is connected in parallel with the second resistor.

[0023] A fourth aspect of the present invention provides a vehicle, comprising the exhaust gas treatment system described in the above embodiment.

[0024] According to the vehicle of the embodiment of the present invention, the exhaust gas treatment system in the above embodiment can detect the failure of the injector in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0025] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0027] Figure 1 is a schematic diagram of an exhaust gas treatment system according to one embodiment of the present invention;

[0028] Figure 2 is a flow chart of a fault detection method for a urea injector according to an embodiment of the present invention;

[0029] Figure 3 is a schematic diagram of voltage changes when a voltage regulator and a driver are started according to an embodiment of the present invention;

[0030] Figure 4 is a flow chart of a fault detection method for a urea injector according to another embodiment of the present invention;

[0031] Figure 5 is a structural block diagram of a fault detection device according to an embodiment of the present invention;

[0032] Figure 6 is a structural block diagram of an exhaust gas treatment system according to an embodiment of the present invention;

[0033] Figure 7 is a structural block diagram of a vehicle according to an embodiment of the present invention.

[0034] Reference numerals:

[0035] Vehicle 100; exhaust gas treatment system 90; fault detection device 80;

[0036] Injector control circuit 1; urea injector 2; controller 3; voltage regulator 11; driver 12; first resistor R1; second resistor R2; first switch S1; second switch S2; first acquisition module 4; second acquisition module 5; determination module 6. DETAILED DESCRIPTION

[0037] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0038] In order to solve the above problems, a first embodiment of the present invention provides a urea injector fault detection method for an exhaust gas treatment system. The method can detect the fault of the injector in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0039] In an embodiment, Figure 1 As shown, the exhaust gas treatment system 90 includes an injector control loop 1, and a urea injector 2 is arranged in the injector control loop.

[0040] Reference below Figure 2 A method for detecting a fault of a urea injector according to an embodiment of the present invention is described as follows: Figure 2 As shown, the fault detection method at least includes: step S1 to step S3.

[0041] Step S1, obtaining the current working state of the urea injector.

[0042] Specifically, the exhaust gas treatment system obtains the current working state of the urea injector.

[0043] Step S2, obtaining the electric energy data of the injector control circuit.

[0044] Specifically, the exhaust gas treatment system obtains the electrical energy data of the injector control loop, wherein the electrical energy data at least includes voltage data and current data, etc., which are not limited.

[0045] Step S3, determining the fault state of the urea injector according to the current working state and electric energy data.

[0046] Specifically, in the related art, the urea injector injects according to the urea demand value of the urea injector calculated by the engine controller to reduce the nitrogen oxides in the exhaust gas. However, when the urea injector fails, the injection accuracy of the urea injector will be affected, thereby causing the problem of excessive nitrogen oxides in the exhaust gas. In order to solve this problem, during the vehicle startup and driving process, the present application timely detects the failure of the injector through the current working state and electric energy data to improve the injection accuracy of the urea injector, so that the injection amount of the urea injector will not deviate, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas. That is to say, for the current working state of the urea injector, the failure state of the urea injector is monitored through the electric energy data of the injector control circuit, for example, the failure state of the urea injector is monitored through the voltage data and current data of the injector control circuit. Therefore, when the urea injector fails, the failure state of the urea injector can be detected in time and accurately, so as to timely remind the user to repair the failure state of the urea injector, thereby improving the injection accuracy of the urea injector, and then avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector. In addition, by promptly reminding users to repair urea injector faults, fault escalation that affects user use of the vehicle is avoided, repair time and cost are reduced, and the occurrence of incomplete repairs is reduced.

[0047] According to the fault detection method of the urea injector of the embodiment of the present invention, the fault state of the urea injector is monitored by the electric energy data of the injector control circuit according to different current working states of the urea injector, so that the fault condition of the injector can be detected in time under different working states, so as to promptly remind the user to repair the fault condition of the urea injector, thereby improving the injection accuracy of the urea injector and avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0048] In some embodiments, the injector control loop includes a voltage regulator for providing a constant voltage to the urea injector and a driver for collecting power data, such as Figure 3As shown, the voltage outputted from the exhaust gas treatment system to the urea injector in the initial stage of power-on increases from 0 to a set voltage value. In order to ensure that a constant voltage is provided to the urea injector each time the power is on, before obtaining the current working state of the urea injector, the voltage regulator is controlled to start to adjust the supply voltage of the urea injector. For example, the voltage regulator adjustment is mainly used to provide a constant voltage to the urea injector when the voltage is unstable when the power is first on. Therefore, by adding a voltage regulator to the injector control loop, the supply voltage of the urea injector is adjusted, thereby avoiding the problem of false alarm of the urea injector caused by unstable voltage in the initial stage of the vehicle power-on, and controlling the driver to start after a preset time, that is, after the voltage regulator is started for a period of time, that is, after the supply voltage is in a stable state, the driver is controlled to start, and the driver collects the electric energy data of the injector control loop to ensure that constant electric energy data can be obtained, thereby avoiding misjudgment of the fault of the urea injector due to receiving the electric energy information in the initial stage of power-on. It should be noted that the start time of the voltage regulator needs to be earlier than the driver to ensure that the driver can obtain constant electric energy data.

[0049] In addition, the engine controller supplies power to the exhaust gas treatment system controller through a relay, and the controller can provide a constant voltage of 12V to the urea injector after adjustment by a voltage regulator, and there is no restriction on this. The power required by the exhaust gas treatment system can also be provided by the vehicle battery, and the normal voltage of the battery is 12V.

[0050] In some embodiments, the electric energy data at least includes the positive electrode voltage of the urea injector, and the fault state of the urea injector is determined according to the current working state and the electric energy data. That is, if the current working state of the urea injector is determined to be the activated state, that is, if the current working state of the urea injector is determined to be the power-only state, the fault state of the urea injector is determined according to the positive electrode voltage of the urea injector collected by the driver, thereby realizing fault detection of the urea injector in the activated state.

[0051] In some embodiments, the current working state of the urea injector after the vehicle is powered on is an activated state, and the fault state of the urea injector is determined according to the positive electrode voltage. Since the positive electrode voltage of the urea injector collected by the driver is very large when the urea injector has a short circuit to the power supply fault, the positive electrode voltage is the power supply voltage of the exhaust gas treatment system, and the positive electrode voltage of the urea injector when the urea injector has a short circuit to the power supply fault is greater than the positive electrode voltage in the normal state, and the positive electrode voltage of the urea injector collected by the driver when the urea injector has a short circuit to the ground fault is very low and almost zero, therefore, in the present application, a preset threshold for detecting the fault state of the urea injector is set in the exhaust gas treatment system, and the positive electrode voltage of the injector control loop collected by the driver is compared with the preset threshold to judge the fault state of the urea injector. state, that is, if the positive electrode voltage is lower than the first preset threshold value, wherein the first preset threshold value is a voltage value calibrated according to the short circuit fault of the urea injector to the ground, such as the first preset threshold value is 1V, at this time the positive electrode voltage of the urea injector is extremely low, then the fault state of the urea injector is determined to be a short circuit fault to the ground; if the positive electrode voltage is higher than the second preset threshold value, wherein the second preset threshold value is a voltage value calibrated according to the short circuit fault of the urea injector to the power supply, such as the second preset threshold value is 4V, at this time the positive electrode voltage of the urea injector is very high, then the fault state of the urea injector is determined to be a short circuit fault to the power supply; if the positive electrode voltage is higher than the first preset threshold value and lower than the second preset threshold value, that is, the positive electrode voltage is in the normal positive electrode voltage range of the urea injector, then it is determined that the positive electrode of the urea injector is in a normal state. In this way, fault detection of the urea injector in the activated state is realized.

[0052] In addition, the first preset threshold and the second preset threshold can be adjusted according to the actual situation of the vehicle.

[0053] In some embodiments, the electric energy data at least includes the cathode voltage of the urea injector, and the fault state of the urea injector is determined according to the current working state and the electric energy data, that is, if the current working state of the urea injector is determined to be the activated state, that is, if the current working state of the urea injector is determined to be the power-on state, the fault state of the urea injector is determined according to the cathode voltage of the urea injector collected by the driver. In this way, fault detection of the urea injector in the activated state is achieved.

[0054] In some embodiments, when the current working state of the urea injector is the activated state, the fault state of the urea injector is determined according to the negative electrode voltage. Since the resistance value in the injector control loop is much larger than the resistance value of the urea injector, the partial pressure of the urea injector in the injector control loop is small, and the voltage drop across the urea injector is small, and the voltage drop is almost negligible compared to the preset threshold value. Therefore, when the urea injector is in a normal state, the negative electrode voltage of the urea injector collected by the driver is almost equal to the positive electrode voltage, that is, the power supply voltage of the exhaust gas treatment system. For example, the negative electrode voltage and the positive electrode voltage of the urea injector are both 3.8V. Therefore, when the urea injector has an open circuit fault, the negative electrode voltage is less than the negative electrode voltage in the normal state. Therefore, this invention In the application, a preset threshold for detecting the fault state of the urea injector is set in the exhaust gas treatment system. The fault state of the urea injector is determined by comparing the negative electrode voltage of the injector control loop collected by the driver with the preset threshold. That is to say, if the negative electrode voltage is lower than the first preset threshold, the negative electrode voltage of the urea injector is small at this time, and the fault state of the urea injector is determined to be an open circuit fault; if the negative electrode voltage is higher than the second preset threshold, the negative electrode voltage of the urea injector is very high at this time, and the fault state of the urea injector is determined to be a short circuit fault to the power supply; if the negative electrode voltage is higher than the first preset threshold and lower than the second preset threshold, that is, the negative electrode voltage is in the normal negative electrode voltage range of the urea injector, it is determined that the negative electrode of the urea injector is in a normal state. In this way, the fault detection of the urea injector in the activated state is realized. In addition, the preset thresholds for the negative electrode voltage and the positive electrode voltage of the injector control loop for detecting the fault state of the urea injector can be different.

[0055] In the embodiment, after the vehicle has been running for a period of time, urea injection is required when the exhaust temperature and the nitrogen oxide concentration in the exhaust gas reach a threshold value, and the vehicle engine controller will send an injection control instruction. Therefore, the fault detection of the urea injector in the activated state can be completed within one minute at the beginning of power-on, and the fault detection of the urea injector in the activated state will continue.

[0056] In some embodiments, Figure 1 As shown, the injector control circuit 1 includes a first resistor R1, a second resistor R2, a first switch S1 and a second switch S2. The first resistor R1, the urea injector 2 and the second resistor R2 are connected in series in sequence. The first switch S1 is connected in parallel with the first resistor R1, and the second switch S2 is connected in parallel with the second resistor R2. The fault detection method also includes: receiving an injection control instruction, controlling the urea injector to enter an action state, wherein in the action state, the first switch and the second switch are controlled to be periodically closed.

[0057] Specifically, after the vehicle has been running for a period of time, when the exhaust temperature and the concentration of nitrogen oxides in the exhaust gas reach the threshold, urea injection is required, and the vehicle engine controller sends an injection control instruction. After receiving the injection control instruction, the exhaust gas treatment system controls the urea injector to enter the action state, that is, controls the urea injector to inject urea. Since the urea injector is in the action state, the urea injector controls the urea injection and the injection amount by opening and closing the internal valve body and the length of time, that is, the urea injection and the injection amount can be controlled by controlling the switch of the urea injector and the length of time of the switch. Therefore, in the action state, the first switch and the second switch are controlled to be closed periodically, so as to realize the control of urea injection and the injection amount, so as to meet the requirements of the exhaust gas treatment system for urea injection and the injection amount of urea. In addition, the closing time of the first switch and the second switch is proportional to the injection amount, and when the first switch and the second switch are closed periodically, the frequency is generally any frequency between 2HZ and 4HZ, and when the first switch and the second switch are in the closed state, the positive voltage of the urea injector is 12V and the negative voltage is 0V, and there is no restriction on this.

[0058] In an embodiment, the action state only occurs when the engine controller has an injection request and the controller of the exhaust gas treatment system commands the nozzle to perform the injection phase.

[0059] In some embodiments, the electric energy data at least includes the working current of the injector control loop, and determining the fault state of the urea injector according to the current working state and the electric energy data includes: determining that the current working state is an action state; and determining the fault state of the urea injector according to the working current. Specifically, when the current working state of the urea injector is an action state, the voltages at both poles of the urea injector will change dynamically due to the rapid closing of the first switch and the second switch, while the working current of the injector control loop is relatively stable. Therefore, the fault state of the urea injector is determined by the magnitude of the working current, thereby realizing the fault detection of the urea injector in the action state.

[0060] In an embodiment, the controller controls the urea pump to operate, and injects the urea solution by transporting the urea solution through the delivery pipe to the nozzle end.

[0061] In some embodiments, when the current working state of the urea injector is the action state, the fault state of the urea injector is determined according to the working current. Since the working current when the positive and negative short circuit fault occurs in the urea injector is much greater than the working current when the urea injector is normal, a preset current value for detecting the fault state of the urea injector is set in the exhaust gas treatment system in the present application. The fault state of the urea injector is determined by comparing the working current of the injector control loop collected by the driver with the preset current value. That is to say, if the working current is higher than the preset current value, wherein the preset current value is the current threshold calibrated according to the positive and negative short circuit fault of the urea injector, and the preset current value can be adjusted according to the actual situation of the vehicle, such as the preset current value is 3.8A, which is not limited to this, then the fault state of the urea injector is determined to be the positive and negative short circuit fault; if the working current is lower than the preset current value, at this time, the working current of the injector control loop is in the normal current range, then the urea injector is determined to be in the normal state. Thus, the fault detection of the urea injector in the action state is realized.

[0062] In the embodiment, if a fault state of the urea injector under different working states is detected, the fault state is reminded through an instrument alarm, so as to promptly remind the user to repair the fault state of the urea injector.

[0063] In an embodiment, the fault condition is reported when the fault state of the urea injector in different working states is detected multiple times in a cycle, for example, three times.

[0064] Reference below Figure 4 The fault detection method of the urea injector according to the embodiment of the present invention is illustrated by way of example, and the specific contents are as follows.

[0065] Step S4, start.

[0066] Step S5, the driver collects the positive electrode voltage of the injector control loop. When the current working state of the urea injector is the activated state, it is determined whether the positive electrode voltage is greater than the first preset threshold value. If so, step S7 is executed, otherwise, step S6 is executed.

[0067] Step S6: determining that the fault state of the urea injector is a short circuit to ground fault.

[0068] Step S7, determining whether the positive electrode voltage is greater than a second preset threshold, if so, executing step S8, otherwise executing step S9.

[0069] In step S8, it is determined that the fault state of the urea injector is a short circuit fault to the power supply.

[0070] Step S9, the driver collects the cathode voltage of the urea injector and determines whether the cathode voltage is greater than a first preset threshold value. If yes, step S11 is executed, otherwise, step S10 is executed.

[0071] In step S10, it is determined that the fault state of the urea injector is an open circuit fault.

[0072] Step S11, determining whether the negative electrode voltage is greater than a second preset threshold, if yes, executing step S8, otherwise executing step S12.

[0073] In step S12, it is determined that the positive electrode or the negative electrode of the urea injector is in a normal state, and then the fault state of the urea injector in the operating state is monitored.

[0074] Step S13, the driver collects the working current of the injector control circuit. When the current working state of the urea injector is the action state, it is determined whether the working current is lower than the preset current value. If so, step S15 is executed, otherwise step S14 is executed.

[0075] In step S14, it is determined that the fault state of the urea injector is a positive and negative electrode short circuit fault.

[0076] In step S15, it is determined that the urea injector is in a normal state.

[0077] Step S16, end.

[0078] A second aspect of the present invention provides a urea injector fault detection device for an exhaust gas treatment system, such as Figure 1 As shown, the exhaust gas treatment system 90 includes an injector control loop 1, and a urea injector 2 is arranged in the injector control loop 1. Figure 5 As shown, the fault detection device 90 includes: a first acquisition module 4 , a second acquisition module 5 and a determination module 6 .

[0079] Among them, the first acquisition module 4 is used to obtain the current working state of the urea injector; the second acquisition module 5 is used to obtain the power data of the injector control circuit; the determination module 6 is used to determine the fault state of the urea injector according to the current working state and the power data.

[0080] According to the fault detection device of the urea injector of the embodiment of the present invention, the determination module monitors the fault state of the urea injector through the electric energy data of the injector control circuit according to different current working states of the urea injector, so that the fault condition of the injector can be detected in time under different working states, so as to promptly remind the user to repair the fault condition of the urea injector, thereby improving the injection accuracy of the urea injector and avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0081] A third aspect of the present invention provides an exhaust gas treatment system 90, such as Figure 1 and Figure 6As shown, it includes: an injector control circuit 1, a urea injector 2 and a controller 3.

[0082] The urea injector 2 is arranged in the injector control circuit 1; the controller 3 is connected to the injector control circuit 1, and is used to execute the fault detection method of the urea injector of the above embodiment. In addition, the controller 3 and the engine controller can exchange signals, and the controller 3 controls the urea injector.

[0083] It should be noted that the specific implementation of the exhaust gas treatment system of the embodiment of the present invention is similar to the specific implementation of the fault detection method of the urea injector of any of the above embodiments of the present invention. Please refer to the description of the method part for details. In order to reduce redundancy, it will not be repeated here.

[0084] According to the exhaust gas treatment system of the embodiment of the present invention, by executing the fault detection method of the urea injector of the above embodiment, the fault of the injector can be detected in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0085] In some embodiments, Figure 1 As shown, the injector control circuit 1 includes: a voltage regulator 11 and a driver 12 .

[0086] The voltage regulator 11 is used to provide a constant voltage for the urea injector, and the driver 12 is used to collect power data. The selection of the driver 12 chip needs to be determined according to actual needs.

[0087] Specifically, in order to ensure that a constant voltage is provided to the urea injector each time the power is turned on, before obtaining the current working state of the urea injector, the voltage regulator is controlled to start adjusting the power supply voltage of the urea injector to provide a constant voltage to the urea injector, thereby avoiding the problem of false alarm of urea injector failure caused by voltage instability in the initial stage of power-on of the vehicle, and the driver is controlled to start after a preset time, and the driver collects the power data of the injector control circuit to ensure that constant power data can be output, thereby avoiding misjudgment of the fault condition of the urea injector due to receiving power information in the initial stage of power-on.

[0088] In some embodiments, Figure 1 As shown, the injector control circuit 1 includes: a first resistor R1, a second resistor R2, a first switch S1 and a second switch S2. The first resistor R1, the urea injector 2 and the second resistor R2 are connected in series in sequence, the first switch S1 is connected in parallel with the first resistor R1, and the second switch S2 is connected in parallel with the second resistor R2.

[0089] Specifically, when the current working state of the urea injector is the activated state, the first switch and the second switch are in the disconnected state; when the current working state of the urea injector is the action state, the urea injection and the injection amount can be controlled by controlling the switch of the urea injector and the duration of the switch, that is, by controlling the periodic closing of the first switch and the second switch, the urea injection and the injection amount can be controlled to meet the requirements of the exhaust gas treatment system for urea injection and urea injection amount. In addition, the resistance values ​​of the first resistor and the second resistor are much larger than the resistance value of the urea injector.

[0090] A fourth aspect of the present invention provides a vehicle 100, such as Figure 7 As shown, the vehicle 100 includes the exhaust gas treatment system 90 described in the above embodiment.

[0091] According to the vehicle of the embodiment of the present invention, the exhaust gas treatment system in the above embodiment can detect the failure of the injector in time to improve the injection accuracy of the urea injector, thereby avoiding the problem of excessive nitrogen oxides in the exhaust gas caused by the injection accuracy of the urea injector.

[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0093] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A method for detecting a fault of a urea injector, characterized in that: For an exhaust gas treatment system, the exhaust gas treatment system includes an injector control loop, the urea injector is arranged in the injector control loop, and the fault detection method includes: Get the current working status of the urea injector; Acquiring electrical energy data of the injector control circuit; A fault state of the urea injector is determined according to the current working state and the electric energy data.

2. The fault detection method of urea injector according to claim 1, characterized in that: The injector control loop includes a voltage regulator for providing a constant voltage to the urea injector and a driver for collecting the electric energy data. Before obtaining the current working state of the urea injector, the fault detection method further includes: The voltage regulator is controlled to start, and the driver is controlled to start after a preset time.

3. The fault detection method for a urea injector according to claim 1 or 2, characterized in that: The electric energy data at least includes a positive electrode voltage of the urea injector, and determining a fault state of the urea injector according to the current working state and the electric energy data includes: Determining that the current working state is an activated state; A fault state of the urea injector is determined according to the positive electrode voltage.

4. The fault detection method of urea injector according to claim 3, characterized in that: Determining a fault state of the urea injector according to the positive electrode voltage includes: If the positive electrode voltage is lower than a first preset threshold, determining that the fault state of the urea injector is a short circuit to ground fault; If the positive electrode voltage is higher than a second preset threshold, determining that the fault state of the urea injector is a short circuit fault to the power supply; If the positive electrode voltage is higher than the first preset threshold and lower than the second preset threshold, it is determined that the positive electrode of the urea injector is in a normal state.

5. The fault detection method of urea injector according to claim 1, characterized in that: The electric energy data at least includes a cathode voltage of the urea injector, and determining a fault state of the urea injector according to the current working state and the electric energy data includes: Determining that the current working state is an activated state; A fault state of the urea injector is determined according to the cathode voltage.

6. The method for detecting a fault of a urea injector according to claim 5, characterized in that: Determining a fault state of the urea injector according to the cathode voltage includes: If the cathode voltage is lower than a first preset threshold, determining that the fault state of the urea injector is an open circuit fault; If the cathode voltage is higher than a second preset threshold, determining that the fault state of the urea injector is a short circuit fault to the power supply; If the cathode voltage is higher than the first preset threshold and lower than the second preset threshold, it is determined that the cathode of the urea injector is in a normal state.

7. The fault detection method of urea injector according to claim 1, characterized in that: The injector control circuit includes a first resistor, a second resistor, a first switch and a second switch, the first resistor, the urea injector and the second resistor are connected in series in sequence, the first switch is connected in parallel with the first resistor, and the second switch is connected in parallel with the second resistor, and the fault detection method further includes: Upon receiving an injection control instruction, the urea injector is controlled to enter an action state, wherein in the action state, the first switch and the second switch are controlled to be closed periodically.

8. The method for detecting a fault of a urea injector according to claim 7, characterized in that: The electric energy data at least includes the operating current of the injector control circuit, and determining the fault state of the urea injector according to the current working state and the electric energy data includes: Determining that the current working state is an action state; A fault state of the urea injector is determined according to the operating current.

9. The method for detecting a fault of a urea injector according to claim 8, characterized in that: Determining a fault state of the urea injector according to the operating current includes: If the working current is higher than the preset current value, it is determined that the fault state of the urea injector is a positive-negative short circuit fault; If the operating current is lower than the preset current value, it is determined that the urea injector is in a normal state.

10. A fault detection device for a urea injector, characterized in that: Used in an exhaust gas treatment system, the exhaust gas treatment system includes an injector control circuit, the urea injector is arranged in the injector control circuit, and the fault detection device includes: A first acquisition module, used for acquiring the current working state of the urea injector; A second acquisition module, used for acquiring electric energy data of the injector control circuit; A determination module is used to determine the fault state of the urea injector according to the current working state and the electric energy data.

11. An exhaust gas treatment system, characterized in that: include: Injector control circuit; a urea injector, wherein the urea injector is arranged in the injector control circuit; A controller is connected to the injector control circuit and is used to execute the urea injector fault detection method according to any one of claims 1 to 9.

12. The exhaust gas treatment system according to claim 11, characterized in that: The injector control circuit comprises: A voltage regulator, used for providing a constant voltage to the urea injector; A driver is used to collect the electric energy data.

13. The exhaust gas treatment system according to claim 11, characterized in that: The injector control circuit comprises: A first resistor, a second resistor, a first switch and a second switch, the first resistor, the urea injector and the second resistor are connected in series in sequence, the first switch is connected in parallel with the first resistor, and the second switch is connected in parallel with the second resistor.

14. A vehicle, characterized in that: A tail gas treatment system comprising any one of claims 11-13.

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