Method for conversion of nitrogen oxides and vehicle
By adjusting the urea injection volume to stabilize nitrogen oxide conversion, the problem of catalyst instability in newly produced vehicles was solved, achieving stability of nitrogen oxide emissions and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GREAT WALL MOTOR CO LTD
- Filing Date
- 2023-06-30
- Publication Date
- 2026-05-15
AI Technical Summary
The catalysts of newly produced vehicles are unstable due to the presence of unknown impurities, and nitrogen oxide emissions do not meet engineering targets or emission regulations. Existing catalyst activation methods increase labor time and costs.
By determining the ammonia storage capacity of the particulate matter trap, the content of stored ammonia, and the rate of nitrogen oxide consumption, the urea injection rate is adjusted to stabilize nitrogen oxide conversion, and the target demand is used to instruct the vehicle to perform nitrogen oxide conversion.
It eliminates the need to activate the catalyst for every new vehicle, achieving stable nitrogen oxide conversion and reducing labor time and costs.
Smart Images
Figure CN116696524B_ABST
Abstract
Description
Technical Field
[0001] This application belongs to the field of automotive technology, and in particular relates to a method for converting nitrogen oxides and a vehicle. Background Technology
[0002] Because the after-treatment of newly produced vehicles contains unknown impurities, such as moisture and solid impurities, these impurities can cover the active sites of the catalyst, causing the performance of the catalytic reduction converter to be unstable. In addition, newly produced vehicles have not been broken in and have greater driving resistance. The initial emission of nitrogen oxides from the engine outlet of the vehicle is greater than that of vehicles after break-in, resulting in the nitrogen oxide emissions of newly produced vehicles at 0km not meeting the engineering target requirements or emission regulations.
[0003] Currently, most manufacturers remove interference from unknown substances in the catalyst by activating it. This can be achieved by increasing exhaust temperature through high-speed vehicle operation or particulate matter capture and regeneration, thus activating the catalyst and preventing the influence of unknown substances on its performance, thereby improving catalyst stability. However, to meet emission regulations, performing this method on every new car would become a bottleneck in vehicle production, increasing labor time and costs. Summary of the Invention
[0004] The purpose of this application is to provide a method and vehicle for converting nitrogen oxides, which aims to solve the problems of high labor time and cost in traditional nitrogen oxide conversion processes.
[0005] A first aspect of this application provides a method for converting nitrogen oxides, the method comprising:
[0006] The first ammonia storage capacity of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion are determined. The first ammonia storage capacity is the maximum content of ammonia that the particulate matter trap can store under the storage target coefficient.
[0007] Based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate, the initial demand for urea injection is determined.
[0008] Based on the first demand, the second demand, and the initial demand, a target demand for urea injection is determined, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector.
[0009] The vehicle is instructed to perform nitrogen oxide conversion based on the target demand for urea injection, so that the nitrogen oxide conversion efficiency is stable during the nitrogen oxide conversion process.
[0010] In some embodiments, determining the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate includes:
[0011] Based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate, the ammonia demand is determined;
[0012] Obtain the first inlet temperature, which is the current inlet temperature of the particulate matter collector;
[0013] Based on the first inlet temperature and the required amount of ammonia, the initial requirement for urea injection is determined.
[0014] In some embodiments, determining the target demand for urea injection based on the first demand, the second demand, and the initial demand includes:
[0015] If the initial demand is between the first demand and the second demand, the initial demand is determined as the target demand.
[0016] If the initial demand is less than the first demand, the first demand is determined as the target demand.
[0017] If the initial demand is greater than the second demand, the second demand is determined as the target demand.
[0018] In some embodiments, before determining the target demand for urea injection based on the first demand, the second demand, and the initial demand, the method further includes:
[0019] The first exhaust flow rate, the first bed temperature, and the first inlet temperature are obtained. The first exhaust flow rate is the current exhaust flow rate of the vehicle, the first bed temperature is the current bed temperature of the particulate filter, and the first inlet temperature is the current inlet temperature of the particulate filter.
[0020] Based on the first exhaust flow rate, the first bed temperature, and the first correspondence, the first demand for urea injection is determined. The first correspondence is the relationship between exhaust flow rate, bed temperature of the particulate matter collector, and urea injection.
[0021] Based on the first exhaust flow rate, the first inlet temperature, and the second correspondence, the second demand for urea injection is determined. The second correspondence is the relationship between exhaust flow rate, inlet temperature of the particulate matter collector, and urea injection quantity.
[0022] In some embodiments, determining the first ammonia storage level in the particulate matter trap includes:
[0023] The capacity and second bed temperature of the particulate matter trap are obtained, wherein the second bed temperature is the current bed temperature of the particulate matter trap;
[0024] Based on the second bed temperature and the third correspondence, the ammonia storage capacity per unit capacity of the particulate matter trap is determined, wherein the third correspondence is the correspondence between the bed temperature and the ammonia storage capacity per unit capacity of the particulate matter trap.
[0025] Based on the capacity and the ammonia storage capacity per unit capacity, the first ammonia storage amount of the particulate matter trap is determined.
[0026] In some embodiments, determining the first ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity includes:
[0027] Based on the capacity and the ammonia storage capacity per unit capacity, a second ammonia storage amount is determined for the particulate matter trap, which is the maximum amount of ammonia that the particulate matter trap can store at the capacity.
[0028] Based on the second bed temperature and the fourth correspondence, the storage target coefficient corresponding to the second bed temperature is determined. The storage target coefficient represents the ammonia storage capacity of the particulate matter trap. The fourth correspondence is the correspondence between the bed temperature of the particulate matter trap and the storage target coefficient.
[0029] The first ammonia storage quantity is determined based on the storage target coefficient and the second ammonia storage quantity.
[0030] In some embodiments, determining the rate of ammonia consumption during nitrogen oxide conversion includes:
[0031] The nitrogen oxide content at the inlet of the particulate matter trap and the second exhaust flow rate are obtained, wherein the second exhaust flow rate is the current exhaust flow rate of the vehicle;
[0032] Based on the nitrogen oxide content and the second exhaust flow rate, the nitrogen oxide flow rate at the inlet of the particulate matter trap is determined;
[0033] Obtain the ammonia-nitrogen molar equivalent ratio of the particulate matter trap and the model conversion efficiency of the particulate matter trap;
[0034] Based on the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency, the nitrogen oxide flow rate is converted to obtain the ammonia consumption rate.
[0035] In some embodiments, instructing the vehicle to perform nitrogen oxide conversion based on the target demand for urea injection includes:
[0036] Based on the target demand for urea injection, the urea decomposition rate of the vehicle under high-temperature conditions is reduced so that the urea injection amount reaches the target demand.
[0037] Based on the adjusted urea injection volume, the vehicle is instructed to perform nitrogen oxide conversion.
[0038] In some embodiments, instructing the vehicle to perform nitrogen oxide conversion based on the target demand for urea injection includes:
[0039] Based on the target demand for urea injection, the storage target coefficient of the particulate matter collector under high temperature conditions is increased so that the urea injection amount reaches the target demand. The storage target coefficient represents the proportion of the ammonia content stored in the particulate matter collector to the maximum ammonia storage capacity of the particulate matter collector.
[0040] Based on the adjusted urea injection volume, the vehicle is instructed to perform nitrogen oxide conversion.
[0041] A second aspect of this application provides a nitrogen oxide conversion apparatus, the apparatus comprising:
[0042] The first determining unit is used to determine the first ammonia storage amount of the particulate matter collector, the content of the stored ammonia, and the ammonia consumption rate during the conversion of nitrogen oxides. The first ammonia storage amount is the maximum content of ammonia stored in the particulate matter collector under the storage target coefficient.
[0043] The second determining unit is used to determine the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate.
[0044] The third determining unit is used to determine the target demand for urea injection based on the first demand, the second demand and the initial demand, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector.
[0045] The indicator unit is used to instruct the vehicle to perform nitrogen oxide conversion based on the target demand amount of urea injection, so as to stabilize the nitrogen oxide conversion efficiency during the nitrogen oxide conversion process.
[0046] In some embodiments, the third determining unit is configured to determine the ammonia demand based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate; obtain a first inlet temperature, the first inlet temperature being the current inlet temperature of the particulate matter collector; and determine the initial demand for urea injection based on the first inlet temperature and the ammonia demand.
[0047] In some embodiments, the third determining unit is configured to: determine the initial demand as the target demand if the initial demand is between the first demand and the second demand; determine the first demand as the target demand if the initial demand is less than the first demand; and determine the second demand as the target demand if the initial demand is greater than the second demand.
[0048] In some embodiments, the apparatus further includes:
[0049] The acquisition unit is used to acquire a first exhaust flow rate, a first bed temperature, and a first inlet temperature, wherein the first exhaust flow rate is the current exhaust flow rate of the vehicle, the first bed temperature is the current bed temperature of the particulate matter trap, and the first inlet temperature is the current inlet temperature of the particulate matter trap.
[0050] The fourth determining unit is used to determine the first demand for urea injection based on the first exhaust flow rate, the first bed temperature and the first correspondence relationship, wherein the first correspondence relationship is the correspondence between exhaust flow rate, bed temperature of particulate matter collector and urea injection amount.
[0051] The fourth determining unit is used to determine the second demand for urea injection based on the first exhaust flow rate, the first inlet temperature, and the second correspondence, wherein the second correspondence is the correspondence between exhaust flow rate, inlet temperature of particulate matter collector, and urea injection quantity.
[0052] In some embodiments, the first determining unit is configured to acquire the capacity and a second bed temperature of the particulate matter trap, wherein the second bed temperature is the current bed temperature of the particulate matter trap; determine the ammonia storage capacity per unit capacity of the particulate matter trap based on the second bed temperature and a third correspondence, wherein the third correspondence is the correspondence between the bed temperature and the ammonia storage capacity per unit capacity of the particulate matter trap; and determine the first ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity.
[0053] In some embodiments, the first determining unit is configured to: determine a second ammonia storage amount for the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity, wherein the second ammonia storage amount is the maximum amount of ammonia that the particulate matter trap can store at the capacity; determine a storage target coefficient corresponding to the second bed temperature based on a second bed temperature and a fourth correspondence, wherein the storage target coefficient represents the ammonia storage capacity of the particulate matter trap, and the fourth correspondence is the correspondence between the bed temperature of the particulate matter trap and the storage target coefficient; and determine the first ammonia storage amount based on the storage target coefficient and the second ammonia storage amount.
[0054] In some embodiments, the first determining unit is configured to: obtain the nitrogen oxide content and a second exhaust flow rate at the inlet of the particulate matter trap, wherein the second exhaust flow rate is the current exhaust flow rate of the vehicle; determine the nitrogen oxide flow rate at the inlet of the particulate matter trap based on the nitrogen oxide content and the second exhaust flow rate; obtain the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency of the particulate matter trap; and convert the nitrogen oxide flow rate based on the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency to obtain the ammonia consumption rate.
[0055] In some embodiments, the indicating unit is configured to reduce the urea decomposition rate of the vehicle under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand; and to instruct the vehicle to perform nitrogen oxide conversion based on the adjusted urea injection amount.
[0056] In some embodiments, the indicating unit is configured to increase the storage target coefficient of the particulate filter under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand, wherein the storage target coefficient represents the proportion of the ammonia content stored in the particulate filter to the maximum ammonia storage capacity of the particulate filter; and instruct the vehicle to perform nitrogen oxide conversion based on the adjusted urea injection amount.
[0057] A third aspect of this application provides a vehicle including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the nitrogen oxide conversion method as described above.
[0058] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the nitrogen oxide conversion method described above.
[0059] The beneficial effects of the embodiments of the present invention compared with the prior art are as follows: In the embodiments of this application, the target demand for urea injection required for nitrogen oxide conversion is determined by the relevant parameters of the particulate matter trap. Based on the target demand, the vehicle is instructed to adjust the urea injection amount. Nitrogen oxide conversion is carried out by the adjusted urea injection amount, so that the actual urea injection amount meets the requirements, thereby achieving stable nitrogen oxide conversion efficiency. As a result, it is not necessary to perform an activation operation for every new vehicle after it rolls off the production line, which can ensure that the new vehicle has 0km emissions, reducing labor time and costs. Attached Figure Description
[0060] Figure 1 A schematic diagram of a post-treatment system based on a nitrogen oxide conversion device is shown in an exemplary embodiment.
[0061] Figure 2 A schematic flowchart of a nitrogen oxide conversion method provided in this application is shown;
[0062] Figure 3 A schematic flowchart of a nitrogen oxide conversion method provided in this application is shown;
[0063] Figure 4 A schematic flowchart of a nitrogen oxide conversion method provided in this application is shown;
[0064] Figure 5 A schematic flowchart of a nitrogen oxide conversion method provided in this application is shown;
[0065] Figure 6 A schematic flowchart of a nitrogen oxide conversion method provided in this application is shown;
[0066] Figure 7 A schematic diagram of a nitrogen oxide conversion device provided in this application is shown;
[0067] Figure 8 This is a schematic diagram of the structure of the electronic device provided in an embodiment of the present invention. Detailed Implementation
[0068] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.
[0069] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0070] The following is an explanation of the terms used in this application.
[0071] Particulate filter: A particulate filter coated with a selective catalytic reduction agent, used to capture particulate matter in exhaust gas and reduce nitrogen oxides in exhaust gas.
[0072] Please refer to Figure 1This illustration shows a schematic diagram of an aftertreatment system based on a nitrogen oxide conversion device provided in an exemplary embodiment. The system includes: a nitrogen oxide conversion device 10, a particulate matter trap 20, a selective catalytic reduction converter 30, a first nitrogen oxide sensor 40, and a second nitrogen oxide sensor 50. The tail end of the nitrogen oxide conversion device 10 is connected to the head end of the particulate matter trap 20, and the tail end of the nitrogen oxide sensor 40 is connected to the head end of the selective catalytic reduction converter 30. The nitrogen oxide sensor 40 is arranged at the rear end of the nitrogen oxide conversion device 10, and the nitrogen oxide sensor 50 is arranged at the rear end of the selective catalytic reduction converter 30. The nitrogen oxide conversion device 10 includes a nitrogen oxide trap (LNT) and a diesel oxidation catalytic converter (DOC).
[0073] The nitrogen oxide conversion device 10 is mainly used to treat total hydrocarbons (THC), non-methane hydrocarbons (NMHC), and carbon monoxide (CO) in exhaust pollutants. When the nitrogen oxide conversion device 10 is a nitrogen oxide trap, it is used to control nitrogen oxide emissions under low temperature and low load conditions. In some embodiments, the nitrogen oxide conversion device 10 has the function of adsorbing nitrogen oxides. That is, when the engine operates under lean-burn (oxygen-rich) combustion conditions, the nitrogen oxide conversion device 10 oxidizes nitric oxide (NO) to generate nitrogen dioxide (NO2), which reacts with the catalyst material BaCO3 to generate nitrate (Ba(NO3)2). This achieves the adsorption and storage of nitrogen oxides. Unoxidized NO is also stored in the nitrogen oxide conversion device 10 in the form of Ce(NO3)2, thereby reducing the nitrogen oxide content in the exhaust. The particulate matter trap 20 is mainly used to treat particulate matter in the exhaust and reduce the particulate matter content in the exhaust. In some embodiments, the particulate filter 20 is used to capture nitrogen oxides that are not completely captured by the nitrogen oxide conversion device 10. The selective catalytic reduction converter 30 is mainly used to treat nitrogen oxides in exhaust gas under high temperature and high load conditions. The nitrogen oxide sensor 40 is arranged at the rear end of the nitrogen oxide conversion device 10 to detect the nitrogen oxide concentration in the exhaust gas at the front end of the particulate filter 20, and the nitrogen oxide sensor 50 is arranged at the rear end of the selective catalytic reduction converter 30 to detect the nitrogen oxide concentration in the exhaust gas at the rear end of the selective catalytic reduction converter 30.
[0074] Because unknown impurities (such as moisture and solid impurities) may cover the active sites of the catalyst during the after-treatment process of new vehicles, the catalysts in the particulate matter trap and selective catalytic reduction unit become unstable, especially with poor performance stability at low and high temperatures. In addition, newly produced vehicles have not been broken in, resulting in greater driving resistance and higher nitrogen oxide emissions from the engine outlet compared to vehicles that have been broken in. These two factors cause the nitrogen oxide emissions from the engine outlet to fail to meet engineering target requirements or emission regulations.
[0075] Currently, most manufacturers remove interference from unknown substances in the catalyst by activating it. This can be achieved by increasing exhaust temperature through high-speed vehicle operation or DPF regeneration, thus eliminating the influence of unknown substances on catalyst performance and improving its stability. However, to meet emission regulations, performing this method on every new vehicle would become a bottleneck in vehicle production, increasing labor time and costs. Therefore, this application provides a nitrogen oxide conversion method that improves the stability of nitrogen oxide conversion without requiring catalyst activation for every new vehicle, thereby reducing labor time and costs.
[0076] See Figure 2 The diagram illustrates a flowchart of a nitrogen oxide conversion method provided in this application. By way of example and not limitation, the method is applied to an electronic device for controlling a vehicle equipped with an aftertreatment system based on the aforementioned nitrogen oxide conversion device.
[0077] S201, the electronic device determines the first ammonia storage amount of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion, wherein the first ammonia storage amount is the maximum content of ammonia that the particulate matter trap can store under the storage target coefficient.
[0078] The stored ammonia content is the current ammonia content stored in the particulate matter collector. In some embodiments, the current stored ammonia content can be determined by an ammonia calculation model. The electronic device determines the current stored ammonia content in the particulate matter collector using this ammonia calculation model, the ammonia content formed by urea injection, and the ammonia content consumed in the reaction with nitrogen oxides. If the ammonia content formed by urea injection is greater than the ammonia content consumed by the reaction with nitrogen oxides, the remaining ammonia will be stored in the particulate matter collector. If the ammonia content formed by urea injection is less than the ammonia content consumed by the reaction with nitrogen oxides, the ammonia stored in the particulate matter collector will be consumed, thereby reducing the ammonia content.
[0079] The electronic device determines the amount of ammonia stored based on the operating time of the particulate filter and the vehicle's exhaust flow rate.
[0080] The first ammonia storage capacity of the particulate matter trap is determined based on the ammonia storage capacity of the particulate matter trap, representing the maximum storage capacity of the particulate matter trap at a target storage coefficient. The process of determining the first ammonia storage capacity by the electronic device can be implemented through the following steps S2011-S2013, including:
[0081] S2011, the electronic device acquires the capacity of the particulate matter trap and the second bed temperature.
[0082] In some embodiments, the electronic device reads the capacity of the particulate matter trap from its specification information. Accordingly, the electronic device obtains stored particulate matter trap specification information and reads the capacity of the particulate matter trap from that specification information.
[0083] The second bed temperature is the current bed temperature of the particulate matter trap. In some embodiments, the electronic device reads the second bed temperature from the operating status of the particulate matter trap. Accordingly, the electronic device acquires the operating status of the particulate matter trap and reads the second bed temperature from the operating status.
[0084] S2012, the electronic device determines the ammonia storage capacity per unit capacity of the particulate matter trap based on the correspondence between the second bed temperature and the third temperature.
[0085] The third correspondence is the relationship between the bed temperature and the ammonia storage capacity per unit capacity of the particulate matter trap. This third correspondence is a pre-stored correspondence in the electronic equipment. See Table 1, which shows the correspondence between the bed temperature and the ammonia storage capacity per unit capacity of a particulate matter trap.
[0086] Table 1
[0087]
[0088]
[0089] See Table 1, where X represents the bed temperature of the particulate matter trap in degrees Celsius, and Y represents the ammonia storage capacity per unit capacity of the particulate matter trap in milligrams per liter.
[0090] In this embodiment of the application, the ammonia storage capacity per unit capacity of the particulate matter trap represents the amount of ammonia stored per liter of the particulate matter trap.
[0091] In this step, the electronic device determines the ammonia storage capacity per unit volume corresponding to the second bed temperature based on the third correspondence. For example, if the second bed temperature is 300 degrees Celsius, then the ammonia storage capacity of the particulate matter trap is 161.00 mg / L.
[0092] S2013, the electronic device determines the first ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity within the unit capacity.
[0093] The electronic device determines the maximum ammonia storage capacity of the particulate matter trap based on its capacity and ammonia storage capacity per unit capacity. Based on this maximum storage capacity and the particulate matter trap's storage target coefficient, a first ammonia storage capacity is determined. (See also...) Figure 3 The process includes the following steps:
[0094] (1) The electronic device determines the second ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity within the unit capacity. The second ammonia storage amount is the maximum amount of ammonia that the particulate matter trap can store under the capacity.
[0095] See Figure 3 The electronic device determines the second ammonia storage capacity of the particulate matter trap by multiplying the capacity of the trap by the ammonia storage capacity per unit capacity.
[0096] (2) The electronic device determines the storage target coefficient corresponding to the second bed temperature based on the correspondence between the second bed temperature and the fourth bed temperature. The storage target coefficient represents the ability of the particulate matter collector to store ammonia.
[0097] The fourth correspondence is the relationship between the bed temperature of the particulate matter trap and the storage target coefficient. This fourth correspondence is a pre-stored correspondence in the electronic device. See Table 2, which shows the correspondence between the bed temperature and the storage target coefficient of a particulate matter trap.
[0098] Table 2
[0099] X Z 175 0.52802 200 0.85001 225 0.95001 250 1.00000 275 1.00000 300 1.00000 350 1.00000 500 1.00000
[0100] See Table 2, where X represents the bed temperature of the particulate matter trap in degrees Celsius, and Z represents the storage target coefficient of the particulate matter trap.
[0101] In this step, the electronic device determines the storage target coefficient corresponding to the second bed temperature based on the fourth correspondence. For example, if the second bed temperature is 225 degrees Celsius, then the storage target coefficient is 0.95001.
[0102] (3) The electronic device determines the first ammonia storage amount based on the storage target coefficient and the second ammonia storage amount.
[0103] See Figure 3 The electronic device determines the first ammonia storage quantity by multiplying the storage target coefficient and the second ammonia storage quantity.
[0104] This consumption rate indicates the rate at which ammonia is consumed during the redox process, specifically during the reaction with nitrogen oxides to produce nitrogen gas and water. Based on this redox process, it is known that the ammonia consumption rate is related to the amount of nitrogen oxides. This process can be achieved through the following steps A1-A4:
[0105] A1, the electronic device acquires the nitrogen oxide content and second exhaust flow rate at the inlet of the particulate filter, the second exhaust flow rate being the current exhaust flow rate of the vehicle.
[0106] The nitrogen oxide content indicates the concentration of nitrogen oxides at the particulate matter trap inlet. In some embodiments, the nitrogen oxide content can be measured by a nitrogen oxide sensor. Accordingly, the electronic device acquires the nitrogen oxide content measured by the nitrogen oxide sensor. The second exhaust flow rate refers to the amount of gas discharged from the exhaust pipe during vehicle operation. The electronic device determines the second exhaust flow rate based on the vehicle's cylinder capacity.
[0107] A2, the electronic device determines the nitrogen oxide flow rate at the inlet of the particulate matter trap based on the nitrogen oxide content and the second exhaust flow rate.
[0108] The nitrogen oxide flow rate represents the amount of nitrogen oxides passing through the particulate matter trap inlet per second. In this step, the electronic equipment performs unit conversions for both the nitrogen oxide content and the second exhaust volume; see [link to relevant documentation]. Figure 4 The electronic device divides the nitrogen oxide content at the particulate matter trap inlet by 10 to the power of -6, divides the second exhaust flow rate by 29, and determines the nitrogen oxide flow rate at the particulate matter trap inlet by multiplying the nitrogen oxide content after conversion of order of magnitude and the second exhaust flow rate.
[0109] A3, the electronic device acquires the ammonia-nitrogen molar equivalent ratio of the particulate matter trap and the model conversion efficiency of the particulate matter trap.
[0110] The conversion efficiency of this model can be determined based on the properties of the particulate matter trap. The ammonia-nitrogen molar equivalent ratio is used to represent the ratio of ammonia to nitrogen oxides in the reaction. This ammonia-nitrogen molar equivalent ratio can be determined by looking up a table using the ratio of nitrogen dioxide to nitric oxide in the nitrogen oxides at the particulate matter trap inlet and the bed temperature of the particulate matter trap. See Table 3, which shows the correspondence between the bed temperature of a particulate matter trap, the ratio of nitrogen dioxide to nitric oxide at the particulate matter trap inlet, and the ammonia-nitrogen molar equivalent ratio.
[0111] Table 3
[0112]
[0113]
[0114] See Table 1, where X represents the bed temperature of the particulate matter trap, Y represents the ratio of nitrogen dioxide to nitric oxide at the inlet of the particulate matter trap, and Z represents the molar equivalent ratio of ammonia nitrogen.
[0115] A4. The electronic device converts the flow rate of nitrogen oxides based on the ammonia-nitrogen molar equivalent ratio and the conversion efficiency of the model to obtain the consumption rate of ammonia.
[0116] Please continue reading Figure 4 The electronic device determines the product of the ammonia nitrogen molar equivalent and the nitrogen oxide flow rate, and then determines the product of this product and the conversion coefficient to obtain the content of equivalent ammonia consumed by nitrogen oxides. The conversion coefficient can be set as needed, for example, the conversion coefficient can be 17.03*1000. The electronic device also determines the product of the content of equivalent ammonia consumed by nitrogen oxides and the conversion efficiency of the model to obtain the ammonia consumption rate.
[0117] S202, the electronic device determines the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate.
[0118] Urea is injected to generate ammonia, which is then consumed in the reaction with nitrogen oxides. Based on the ammonia consumption rate determined in steps A1-A4 of step 201, the required amount of ammonia to meet this consumption rate is determined. Based on this ammonia requirement, the initial demand for urea injection is determined.
[0119] The process can be as follows: the electronic device determines the ammonia demand based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate; obtains the first inlet temperature, which is the current inlet temperature of the particulate matter collector; and determines the initial demand for urea injection based on the first inlet temperature and the ammonia demand.
[0120] See Figure 5 The electronic device determines the difference between the first ammonia storage amount and the content of stored ammonia, determines the sum of the difference and the ammonia consumption rate, obtains the ammonia injection demand, determines the urea decomposition rate corresponding to the inlet temperature based on the inlet temperature of the particulate matter collector, and determines the initial demand for the urea injection amount based on the urea decomposition rate and the ammonia injection demand.
[0121] S203, the electronic device determines the target demand for urea injection based on the first demand, the second demand, and the initial demand, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector.
[0122] The electronic device limits the initial demand based on the first demand and the second demand to obtain the target demand. The process of limiting the initial demand based on the first demand and the second demand can be as follows: if the initial demand is between the first demand and the second demand, the initial demand is determined as the target demand; if the initial demand is less than the first demand, the first demand is determined as the target demand; if the initial demand is greater than the second demand, the second demand is determined as the target demand.
[0123] S204, the electronic equipment instructs the vehicle to perform nitrogen oxide conversion based on the target demand for urea injection, so as to stabilize the nitrogen oxide conversion efficiency during the nitrogen oxide conversion process.
[0124] The electronic equipment instructs the vehicle to adjust the current urea injection quantity based on the target demand for urea injection, so that the vehicle's urea injection quantity meets the requirements for the vehicle's nitrogen oxide conversion.
[0125] In some embodiments, the electronic device reduces the urea decomposition rate of the vehicle under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand; and instructs the vehicle to perform nitrogen oxide conversion based on the adjusted urea injection amount.
[0126] Generally, urea undergoes hydrolysis followed by pyrolysis, and the decomposition rate is either the pyrolysis rate or the hydrolysis rate of the urea. See Table 4, which shows a correlation between the urea decomposition rate and the inlet temperature of a particulate matter collector.
[0127] Table 4
[0128] X Z 175 0.95 200 0.95 225 0.95 250 1.00 275 1.00 350 0.93 400 0.90 600 0.80
[0129] Where X represents the inlet temperature of the particulate matter collector in degrees Celsius, and Z represents the urea decomposition rate.
[0130] In this implementation, the electronic device instructs the vehicle to reduce the urea decomposition rate under high-temperature conditions, thereby reducing the pyrolysis rate and / or hydrolysis rate of urea so that the urea injection quantity can meet the requirements for nitrogen oxide conversion, thus stabilizing the nitrogen oxide conversion efficiency.
[0131] In some embodiments, the electronic device increases the storage target coefficient of the particulate filter under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand, the storage target coefficient representing the particulate filter's ability to store ammonia; and instructs the vehicle to perform nitrogen oxide conversion based on the adjusted urea injection amount.
[0132] In this implementation, the electronic device instructs the vehicle to increase the storage target coefficient of the particulate matter filter under high-temperature conditions, thereby increasing the ammonia storage capacity of the particulate matter filter and storing more ammonia so that the urea injection volume can meet the requirements for nitrogen oxide conversion, thus stabilizing the nitrogen oxide conversion efficiency.
[0133] It should be noted that in the embodiments of this application, by adjusting the urea injection amount to achieve the target demand, the ammonia-to-nitrogen ratio (NSR) in the nitrogen oxide conversion process is controlled at 0.75 to 1.2, thereby ensuring the stability of nitrogen oxide conversion efficiency while improving nitrogen oxide conversion efficiency.
[0134] It should be noted that the embodiments of this application can be executed under high-temperature conditions. Accordingly, before this step, the electronic device acquires the vehicle's driving data; based on the driving data, it is determined that the vehicle is under high-temperature conditions. If the vehicle is under high-temperature conditions, the vehicle is instructed to perform nitrogen oxide conversion by increasing the urea injection volume as provided in the embodiments of this application; if the vehicle is not under high-temperature conditions, a conventional urea injection method is selected to instruct the vehicle to perform nitrogen oxide conversion.
[0135] In this embodiment, the target amount of urea injection required for nitrogen oxide conversion is determined by the relevant parameters of the particulate matter filter. Based on this target amount, the vehicle is instructed to adjust the amount of urea injection. Nitrogen oxide conversion is carried out by the adjusted amount of urea injection, so that the actual amount of urea injection meets the requirements, thereby achieving stable nitrogen oxide conversion efficiency. As a result, it is not necessary to perform an activation operation on every new vehicle after it rolls off the production line, which can ensure that the new vehicle has zero emissions at 0km, reducing labor time and costs.
[0136] See Figure 6 The diagram illustrates a flowchart of a nitrogen oxide conversion method provided in this application. By way of example and not limitation, the method is applied to an electronic device for controlling a vehicle equipped with an aftertreatment system based on the aforementioned nitrogen oxide conversion device.
[0137] S601, the electronic device determines the first ammonia storage amount of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion, wherein the first ammonia storage amount is the maximum content of ammonia that the particulate matter trap can store under the storage target coefficient.
[0138] This step is based on the same principle as step S201, and will not be repeated here.
[0139] S602, the electronic device determines the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate.
[0140] This step is based on the same principle as step S202, and will not be repeated here.
[0141] S603, the electronic device acquires a first exhaust flow rate, a first bed temperature, and a first inlet temperature, wherein the first exhaust flow rate is the current exhaust flow rate of the vehicle, the first bed temperature is the current bed temperature of the particulate filter, and the first inlet temperature is the current inlet temperature of the particulate filter.
[0142] The process by which the electronic device obtains the first exhaust flow rate is the same in principle as the process by which the electronic device obtains the second exhaust flow rate in step A1 of step S201, and will not be described again here. Furthermore, the first exhaust flow rate and the second exhaust flow rate may be the same or different exhaust flow rates; in this embodiment, no specific limitation is made in this regard.
[0143] The process by which the electronic device acquires the first bed temperature is based on the same principle as the process by which the electronic device acquires the second bed temperature in step S2011, and will not be described again here. Furthermore, the first bed temperature and the second bed temperature may be the same or different bed temperatures; this embodiment of the application does not specifically limit this.
[0144] The first inlet temperature is the current inlet temperature of the particulate matter collector. In some embodiments, the operating status of the particulate matter collector is obtained, and the first inlet temperature is read from the operating status.
[0145] S604, the electronic device determines the first demand for urea injection based on the first exhaust flow rate, the first bed temperature, and the first correspondence, wherein the first correspondence is the correspondence between the exhaust flow rate, the bed temperature of the particulate matter collector, and the urea injection amount.
[0146] The first correspondence is determined based on the injection characteristics of the urea nozzle, as shown in Table 5, which illustrates one such first correspondence.
[0147] Table 5
[0148]
[0149] Where X represents the bed temperature of the particulate matter collector, Y represents the exhaust flow rate, and Z represents the minimum urea injection rate.
[0150] S605, the electronic device determines the second demand for urea injection based on the first exhaust flow rate, the first inlet temperature, and the second correspondence, wherein the second correspondence is the correspondence between the exhaust flow rate, the inlet temperature of the particulate matter collector, and the urea injection quantity.
[0151] This second correspondence can be determined by the critical point of crystallization caused by urea injection, see Table 6, which shows one such second correspondence.
[0152] Table 6
[0153]
[0154] Where X represents the inlet temperature of the particulate matter collector, Y represents the exhaust flow rate, and Z represents the maximum urea injection rate.
[0155] The electronic device determines the target demand that meets the requirements based on the first demand and the second demand, so that the target demand is within the second demand and the first demand, thereby improving the requirement to ensure that the vehicle can achieve the target demand and ensuring the execution of the plan.
[0156] S606 instructs vehicles to perform nitrogen oxide conversion based on the target demand for urea injection, so as to stabilize the nitrogen oxide conversion efficiency during the nitrogen oxide conversion process.
[0157] This step is based on the same principle as step S204, and will not be repeated here.
[0158] In this embodiment, the target amount of urea injection required for nitrogen oxide conversion is determined by the relevant parameters of the particulate matter filter. Based on this target amount, the vehicle is instructed to adjust the amount of urea injection. Nitrogen oxide conversion is carried out by the adjusted amount of urea injection, so that the actual amount of urea injection meets the requirements, thereby achieving stable nitrogen oxide conversion efficiency. As a result, it is not necessary to perform an activation operation on every new vehicle after it rolls off the production line, which can ensure that the new vehicle has zero emissions at 0km, reducing labor time and costs.
[0159] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.
[0160] See Figure 7 It shows a schematic diagram of a nitrogen oxide conversion device provided in this application, including various units used to perform the various steps in the above embodiments, see [link to relevant documentation]. Figure 7 The nitrogen oxide conversion device includes:
[0161] The first determining unit 701 is used to determine the first ammonia storage amount of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion. The first ammonia storage amount is the maximum content of ammonia stored in the particulate matter trap under the storage target coefficient.
[0162] The second determining unit 702 is used to determine the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate.
[0163] The third determining unit 703 is used to determine the target demand for urea injection based on the first demand, the second demand and the initial demand, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector.
[0164] The indicator unit 704 is used to instruct the vehicle to perform nitrogen oxide conversion based on the target demand amount of the urea injection, so as to stabilize the nitrogen oxide conversion efficiency during the nitrogen oxide conversion process.
[0165] In some embodiments, the third determining unit 703 is configured to determine the ammonia demand based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate; obtain a first inlet temperature, which is the current inlet temperature of the particulate matter collector; and determine the initial demand for urea injection based on the first inlet temperature and the ammonia demand.
[0166] In some embodiments, the third determining unit 703 is configured to determine the initial demand as the target demand if the initial demand is between the first demand and the second demand; determine the first demand as the target demand if the initial demand is less than the first demand; and determine the second demand as the target demand if the initial demand is greater than the second demand.
[0167] In some embodiments, the device further includes:
[0168] The acquisition unit is used to acquire a first exhaust flow rate, a first bed temperature, and a first inlet temperature, wherein the first exhaust flow rate is the current exhaust flow rate of the vehicle, the first bed temperature is the current bed temperature of the particulate filter, and the first inlet temperature is the current inlet temperature of the particulate filter.
[0169] The fourth determining unit is used to determine the first demand for urea injection based on the first exhaust flow rate, the first bed temperature and the first correspondence relationship, wherein the first correspondence relationship is the correspondence between the exhaust flow rate, the bed temperature of the particulate matter collector and the urea injection amount.
[0170] The fourth determining unit is used to determine the second demand for urea injection based on the first exhaust flow rate, the first inlet temperature, and the second correspondence, wherein the second correspondence is the correspondence between the exhaust flow rate, the inlet temperature of the particulate matter collector, and the urea injection quantity.
[0171] In some embodiments, the first determining unit 701 is configured to acquire the capacity and a second bed temperature of the particulate matter trap, the second bed temperature being the current bed temperature of the particulate matter trap; determine the ammonia storage capacity per unit capacity of the particulate matter trap based on the second bed temperature and a third correspondence, the third correspondence being the correspondence between the bed temperature and the ammonia storage capacity per unit capacity of the particulate matter trap; and determine the first ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity.
[0172] In some embodiments, the first determining unit 701 is configured to: determine a second ammonia storage amount for the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity, wherein the second ammonia storage amount is the maximum amount of ammonia that the particulate matter trap can store at that capacity; determine a storage target coefficient corresponding to the second bed temperature based on the second bed temperature and a fourth correspondence, wherein the storage target coefficient represents the ammonia storage capacity of the particulate matter trap, and the fourth correspondence is the correspondence between the bed temperature of the particulate matter trap and the storage target coefficient; and determine a first ammonia storage amount based on the storage target coefficient and the second ammonia storage amount.
[0173] In some embodiments, the first determining unit 701 is configured to obtain the nitrogen oxide content and a second exhaust flow rate at the inlet of the particulate matter trap, wherein the second exhaust flow rate is the current exhaust flow rate of the vehicle; determine the nitrogen oxide flow rate at the inlet of the particulate matter trap based on the nitrogen oxide content and the second exhaust flow rate; obtain the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency of the particulate matter trap; and convert the nitrogen oxide flow rate based on the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency to obtain the ammonia consumption rate.
[0174] In some embodiments, the indicating unit 704 is used to reduce the urea decomposition rate of the vehicle under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand; and to instruct the vehicle to perform nitrogen oxide conversion based on the adjusted urea injection amount.
[0175] In some embodiments, the indicating unit 704 is used to increase the storage target coefficient of the particulate filter under high-temperature conditions based on the target demand for urea injection, so that the urea injection amount reaches the target demand. The storage target coefficient represents the proportion of the ammonia content stored in the particulate filter to the maximum ammonia storage capacity of the particulate filter. Based on the adjusted urea injection amount, the indicating unit 704 instructs the vehicle to perform nitrogen oxide conversion.
[0176] In this embodiment, the target amount of urea injection required for nitrogen oxide conversion is determined by the relevant parameters of the particulate matter filter. Based on this target amount, the vehicle is instructed to adjust the amount of urea injection. Nitrogen oxide conversion is carried out by the adjusted amount of urea injection, so that the actual amount of urea injection meets the requirements, thereby achieving stable nitrogen oxide conversion efficiency. As a result, it is not necessary to perform an activation operation on every new vehicle after it rolls off the production line, which can ensure that the new vehicle has zero emissions at 0km, reducing labor time and costs.
[0177] Figure 8 This is a schematic diagram of an electronic device provided in one embodiment of this application. For example... Figure 8As shown, the electronic device 8 of this embodiment includes: a processor 80, a memory 81, and a computer program 82 stored in the memory 81 and executable on the processor 80, such as a nitrogen oxide conversion program. When the processor 80 executes the computer program 82, it implements the steps in the various nitrogen oxide conversion method embodiments described above, for example... Figure 2 Steps S201 to S204 are shown. Alternatively, when the processor 80 executes the computer program 82, it implements the functions of each module / unit in the above-described device embodiments, for example... Figure 7 The functions of units 701 to 704 are shown.
[0178] For example, the computer program 82 can be divided into one or more modules / units, which are stored in the memory 81 and executed by the processor 80 to complete this application. The one or more modules / units can be a series of computer program instruction segments capable of performing specific functions, which describe the execution process of the computer program 82 in the electronic device 8. For example, the computer program 82 can be divided into a first determining unit, a second determining unit, a third determining unit, and an instruction unit, with the specific functions of each unit as follows:
[0179] The first determining unit 701 is used to determine the first ammonia storage amount of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion. The first ammonia storage amount is the maximum content of ammonia stored in the particulate matter trap under the storage target coefficient.
[0180] The second determining unit 702 is used to determine the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate.
[0181] The third determining unit 703 is used to determine the target demand for urea injection based on the first demand, the second demand and the initial demand, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector.
[0182] The indicator unit 704 is used to instruct the vehicle to perform nitrogen oxide conversion based on the target demand amount of the urea injection, so as to stabilize the nitrogen oxide conversion efficiency during the nitrogen oxide conversion process.
[0183] The electronic device 8 can be a vehicle-mounted terminal, a handheld computer, or a cloud server, etc., used for controlling the vehicle. The electronic device 8 may include, but is not limited to, a processor 80 and a memory 81. Those skilled in the art will understand that... Figure 8This is merely an example of electronic device 8 and does not constitute a limitation on electronic device 8. It may include more or fewer components than shown, or combine certain components, or different components. For example, electronic device 8 may also include input / output devices, network access devices, buses, etc.
[0184] The processor 80 may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor.
[0185] The memory 81 can be an internal storage unit of the electronic device 8, such as a hard disk or memory. The memory 81 can also be an external storage device of the electronic device 8, such as a plug-in hard disk, Smart Media Card (SMC), Secure Digital (SD) card, or Flash Card. Furthermore, the memory 81 can include both internal and external storage units of the electronic device 8. The memory 81 is used to store the computer program and other programs and data required by the terminal device. The memory 81 can also be used to temporarily store data that has been output or will be output.
[0186] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.
[0187] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0188] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.
[0189] In the embodiments provided in this application, it should be understood that the disclosed devices / terminal equipment and methods can be implemented in other ways. For example, the device / terminal equipment embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces; the indirect coupling or communication connection between devices or units may be electrical, mechanical, or other forms.
[0190] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0191] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0192] If the integrated module / unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable medium can include: any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium can be appropriately added or removed according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media do not include electrical carrier signals and telecommunication signals.
[0193] This application also provides a vehicle including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps described in the various method embodiments above.
[0194] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps described in the above method embodiments.
[0195] This application also provides a computer program product that, when run on a mobile terminal, enables the mobile terminal to implement the steps described in the various method embodiments above.
[0196] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.
Claims
1. A method for converting nitrogen oxides, characterized in that, The method includes: The first ammonia storage capacity of the particulate matter trap, the content of stored ammonia, and the ammonia consumption rate during nitrogen oxide conversion are determined. The first ammonia storage capacity is the maximum content of ammonia that the particulate matter trap can store under the storage target coefficient. Based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate, the initial demand for urea injection is determined. Based on the first demand, the second demand, and the initial demand, a target demand for urea injection is determined, wherein the first demand is less than the second demand, the first demand is the minimum amount of urea injection allowed by the particulate matter collector, and the second demand is the maximum amount of urea injection allowed by the particulate matter collector. The vehicle is instructed to perform nitrogen oxide conversion based on the target demand for urea injection, so that the nitrogen oxide conversion efficiency is stable during the nitrogen oxide conversion process. Determining the first ammonia storage capacity of the particulate matter trap includes: The capacity and second bed temperature of the particulate matter trap are obtained, wherein the second bed temperature is the current bed temperature of the particulate matter trap; Based on the second bed temperature and the third correspondence, the ammonia storage capacity per unit capacity of the particulate matter trap is determined, wherein the third correspondence is the correspondence between the bed temperature and the ammonia storage capacity per unit capacity of the particulate matter trap. Based on the capacity and the ammonia storage capacity per unit capacity, the first ammonia storage amount of the particulate matter trap is determined.
2. The method as described in claim 1, characterized in that, Determining the initial demand for urea injection based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate includes: Based on the first ammonia storage amount, the content of the stored ammonia, and the ammonia consumption rate, the ammonia demand is determined; Obtain the first inlet temperature, which is the current inlet temperature of the particulate matter collector; Based on the first inlet temperature and the required amount of ammonia, the initial requirement for urea injection is determined.
3. The method as described in claim 1, characterized in that, Determining the target demand for urea injection based on the first demand, the second demand, and the initial demand includes: If the initial demand is between the first demand and the second demand, the initial demand is determined as the target demand. If the initial demand is less than the first demand, the first demand is determined as the target demand. If the initial demand is greater than the second demand, the second demand is determined as the target demand.
4. The method as described in claim 1 or 3, characterized in that, Before determining the target demand for urea injection based on the first demand, the second demand, and the initial demand, the method further includes: The first exhaust flow rate, the first bed temperature, and the first inlet temperature are obtained. The first exhaust flow rate is the current exhaust flow rate of the vehicle, the first bed temperature is the current bed temperature of the particulate filter, and the first inlet temperature is the current inlet temperature of the particulate filter. Based on the first exhaust flow rate, the first bed temperature, and the first correspondence, the first demand for urea injection is determined. The first correspondence is the relationship between exhaust flow rate, bed temperature of the particulate matter collector, and urea injection. Based on the first exhaust flow rate, the first inlet temperature, and the second correspondence, the second demand for urea injection is determined. The second correspondence is the relationship between exhaust flow rate, inlet temperature of the particulate matter collector, and urea injection quantity.
5. The method as described in claim 1, characterized in that, Determining the first ammonia storage amount of the particulate matter trap based on the capacity and the ammonia storage capacity per unit capacity includes: Based on the capacity and the ammonia storage capacity per unit capacity, a second ammonia storage amount is determined for the particulate matter trap, which is the maximum amount of ammonia that the particulate matter trap can store at the capacity. Based on the second bed temperature and the fourth correspondence, the storage target coefficient corresponding to the second bed temperature is determined. The storage target coefficient represents the ammonia storage capacity of the particulate matter trap. The fourth correspondence is the correspondence between the bed temperature of the particulate matter trap and the storage target coefficient. The first ammonia storage quantity is determined based on the storage target coefficient and the second ammonia storage quantity.
6. The method as described in claim 1, characterized in that, Determining the rate of ammonia consumption during nitrogen oxide conversion includes: The nitrogen oxide content at the inlet of the particulate matter trap and the second exhaust flow rate are obtained, wherein the second exhaust flow rate is the current exhaust flow rate of the vehicle; Based on the nitrogen oxide content and the second exhaust flow rate, the nitrogen oxide flow rate at the inlet of the particulate matter trap is determined; Obtain the ammonia-nitrogen molar equivalent ratio of the particulate matter trap and the model conversion efficiency of the particulate matter trap; Based on the ammonia-nitrogen molar equivalent ratio and the model conversion efficiency, the nitrogen oxide flow rate is converted to obtain the ammonia consumption rate.
7. The method as described in claim 1, characterized in that, The method of instructing vehicles to perform nitrogen oxide conversion based on the target demand for urea injection includes: Based on the target demand for urea injection, the urea decomposition rate of the vehicle under high-temperature conditions is reduced so that the urea injection amount reaches the target demand. Based on the adjusted urea injection volume, the vehicle is instructed to perform nitrogen oxide conversion.
8. The method as described in claim 1, characterized in that, The method of instructing vehicles to perform nitrogen oxide conversion based on the target demand for urea injection includes: Based on the target demand for urea injection, the storage target coefficient of the particulate matter collector under high temperature conditions is increased so that the urea injection amount reaches the target demand. The storage target coefficient represents the proportion of the ammonia content stored in the particulate matter collector to the maximum ammonia storage capacity of the particulate matter collector. Based on the adjusted urea injection volume, the vehicle is instructed to perform nitrogen oxide conversion.
9. A vehicle, characterized in that, The vehicle includes a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor executes the computer program to implement the nitrogen oxide conversion method as described in any one of claims 1 to 8.