Hydrogen internal combustion engine aftertreatment device and control method, engine

Abstract

The application provides a hydrogen internal combustion engine aftertreatment device and control method and an engine, and applies to the technical field of automobile engines and relates to the technical field of hydrogen internal combustion engine aftertreatment devices. The intelligent control valve in the hydrogen internal combustion engine aftertreatment device is connected with an exhaust inlet, an input end of H2SCR and an input end of a first pipeline respectively, an output end of the first pipeline is connected with SCR, and an output end of H2SCR is connected with SCR through a second pipeline. When the exhaust temperature is less than a first preset temperature, the intelligent control valve controls H2SCR to be conductive with the exhaust inlet, the first pipeline is not conductive with the exhaust inlet, H2SCR is used to convert NOx in exhaust, the problem of urea crystallization at low temperature is solved, and the conversion rate of NOx is reduced. When the exhaust temperature is not less than the first preset temperature, the intelligent control valve controls H2SCR to be not conductive with the exhaust inlet, the first pipeline is conductive with the exhaust inlet, SCR is used to convert NOx in exhaust, and the conversion rate of NOx is improved by combining H2SCR and SCR.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of automobile engines, and in particular relates to a hydrogen internal combustion engine aftertreatment device and control method and an engine. BACKGROUND

[0002] NOx (nitrogen oxide) is a major pollutant in automobile exhaust, which includes nitric oxide (NO), nitrogen dioxide (NO2) and other nitrogen oxides. These compounds are not only harmful to the environment, but also have adverse effects on human health. Therefore, it is crucial to effectively reduce NOx emissions in vehicle exhaust treatment systems.

[0003] Currently, the main method to reduce vehicle emissions of NOx is to use selective catalytic reduction (SCR) technology. The SCR system adds ammonia or urea as a reducing agent to convert NOx into nitrogen and water under the action of a specific catalyst. However, this treatment technology has problems such as low-temperature urea crystallization, resulting in low conversion efficiency of NOx in vehicle exhaust. SUMMARY

[0004] Therefore, the present application provides a hydrogen internal combustion engine aftertreatment device and control method and an engine. In the scheme provided by the present application, H2SCR is used to convert NOx in exhaust gas at low temperature, solving the problem of urea crystallization in SCR at low temperature and reducing the conversion rate of NOx. A heat dissipation device is used to dissipate heat and cool the H2SCR, thereby increasing the temperature range applicable to the H2SCR. At medium and high temperatures, SCR is used to convert NOx in exhaust gas. By combining H2SCR and SCR, the conversion rate of NOx is improved.

[0005] To achieve the above-mentioned purpose, the embodiments of the present application provide the following technical solutions:

[0006] A hydrogen internal combustion engine aftertreatment device, comprising:

[0007] a heat dissipation device, a selective catalytic reducer (SCR) using NH3 as a reducing agent, and a selective hydrogen catalytic reduction catalyst (H2SCR) using H2 as a reducing agent;

[0008] The input end of the SCR is connected to the output end of the first pipeline and the output end of the second pipeline, respectively;

[0009] The output end of the H2SCR is connected to the input end of the second pipeline;

[0010] The input end of the H2SCR and the input end of the first pipeline are both connected to an intelligent control valve;

[0011] The intelligent control valve is used for controlling the conduction state of the input end of the H2SCR and the input end of the first pipeline and the exhaust inlet.

[0012] The heat dissipation device is used for dissipating heat of the H2SCR.

[0013] The hydrogen internal combustion engine aftertreatment device can further comprise a heat dissipation fin arranged on the H2SCR.

[0014] The hydrogen internal combustion engine aftertreatment device can further comprise a heat dissipation device.

[0015] A wind regulator.

[0016] The wind regulator is used for adjusting the wind flow of the heat dissipation device blowing to the H2SCR.

[0017] A hydrogen internal combustion engine aftertreatment device control method is applied to a hydrogen internal combustion engine aftertreatment device, and the method comprises the following steps of:

[0018] Real-time collection of working state information of the hydrogen internal combustion engine aftertreatment device;

[0019] When the exhaust temperature in the working state information is less than a first preset temperature, controlling the exhaust to be treated to flow through a selective hydrogen catalytic reduction catalyst H2SCR using H2 as a reducing agent in the hydrogen internal combustion engine aftertreatment device first, then flow through a selective catalytic reduction device SCR using NH3 as a reducing agent in the hydrogen internal combustion engine aftertreatment device, and using a preset low-temperature exhaust treatment strategy to treat NOx in the exhaust using the H2SCR and the SCR.

[0020] When the exhaust temperature in the working state information is greater than or equal to the first preset temperature, controlling the exhaust to be treated to flow through the SCR directly without flowing through the H2SCR, and using a preset high-temperature exhaust treatment strategy to control a preset urea nozzle to spray urea and make the SCR treat NOx in the exhaust.

[0021] The method can further comprise the following steps of:

[0022] Judging whether the exhaust temperature in the working state information is less than or equal to a second preset temperature in the low-temperature exhaust treatment strategy;

[0023] When the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, judging whether a tail exhaust NOx value in the working state information is less than or equal to an NOx limit value in the low-temperature exhaust treatment strategy.

[0024] When the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value, the H2SCR is used to reduce the NOx in the exhaust gas, and the SCR is used to treat the NOx in the exhaust gas treated by the H2SCR.

[0025] When the tail exhaust NOx value in the working state information is greater than the NOx limit value, hydrogen is supplemented to the exhaust gas before the exhaust gas flows to the H2SCR, the H2SCR is used to treat the NOx in the exhaust gas supplemented with hydrogen, and the SCR is used to treat the NOx in the exhaust gas treated by the H2SCR.

[0026] The method described above, optionally, the hydrogen supplementing to the exhaust gas comprises:

[0027] Obtaining a hydrogen supplement parameter;

[0028] Using the hydrogen supplement parameter to determine a hydrogen supplement value, and controlling the injection amount of hydrogen injected into the exhaust gas by a preset hydrogen injector according to the hydrogen supplement value.

[0029] The method described above, optionally, further comprises:

[0030] When the exhaust gas temperature in the working state information is greater than the second preset temperature in the low-temperature exhaust treatment strategy, based on a preset heat dissipation strategy, a heat dissipation device in the hydrogen internal combustion engine aftertreatment device is controlled to perform heat dissipation treatment on the H2SCR, and the exhaust gas is treated by the SCR after being treated by the H2SCR.

[0031] The method described above, optionally, based on a preset heat dissipation strategy, the heat dissipation device in the hydrogen internal combustion engine aftertreatment device is controlled to perform heat dissipation treatment on the H2SCR, comprising:

[0032] Controlling the opening degree of the wind power regulator in the heat dissipation device to be 100%, so that the gas used for heat dissipation performs heat dissipation treatment on the H2SCR after passing through the wind power regulator, and adjusting the opening degree of the wind power regulator according to the temperature change of the H2SCR.

[0033] The method described above, optionally, the control of the preset urea nozzle to spray urea comprises:

[0034] Obtaining a urea supplement parameter;

[0035] Using the urea supplement parameter to determine the urea injection amount, and controlling the urea nozzle to spray urea according to the urea injection amount.

[0036] An engine comprising the hydrogen internal combustion engine aftertreatment device described above.

[0037] Compared with the prior art, the application has the following advantages:

[0038] The application provides a hydrogen internal combustion engine aftertreatment device and a control method and an engine, and specifically comprises: an intelligent control valve in the hydrogen internal combustion engine aftertreatment device is connected with an exhaust inlet, an input end of an H2SCR and an input end of a first pipeline respectively, an output end of the first pipeline is connected with an SCR, and an output end of the H2SCR is connected with the SCR through a second pipeline; the intelligent control valve is used for controlling the conduction state of the input end of the H2SCR and the input end of the first pipeline and the exhaust inlet; when the exhaust temperature of the hydrogen internal combustion engine aftertreatment device is less than a first preset temperature, the intelligent control valve controls the input end of the H2SCR to be conducted with the exhaust inlet, and the input end of the first pipeline is not conducted with the exhaust inlet; in the case of low temperature, the H2SCR is used to convert NOx in the exhaust, the problem of low NOx conversion rate caused by urea crystallization at low temperature is solved, and the NOx conversion rate in the exhaust at low temperature is improved; when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls the input end of the H2SCR to be not conducted with the exhaust inlet, and the input end of the first pipeline is conducted with the exhaust inlet, so that in the case of high temperature, the SCR is used to convert NOx in the exhaust. Different NOx conversion modes are used at different temperatures, the NOx conversion rate is improved, and the NOx emission of automobile exhaust is reduced. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of the provided drawings.

[0040] Figure 1 A structure schematic diagram of a hydrogen internal combustion engine aftertreatment device provided by the embodiment of the application;

[0041] Figure 2 A flowchart example diagram of a hydrogen internal combustion engine aftertreatment device processing method provided by the embodiment of the application;

[0042] Figure 3 A flowchart example diagram of using H2SCR and SCR to process NOx in exhaust provided by the embodiment of the application;

[0043] Figure 4 An example diagram of the full opening of the temperature regulating grid provided by the embodiment of the application;

[0044] Figure 5 An example diagram of the full closing of the temperature regulating grid provided by the embodiment of the application;

[0045] Figure 6An opening degree adjustment example diagram of the temperature regulating grille provided for the embodiment of the present application is shown in the following figure.

[0046] Figure 7 Another flow chart of the control method of the hydrogen internal combustion engine aftertreatment device provided for the embodiment of the present application is shown in the following figure. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0048] In the present application, the term “comprising”, “containing” or any other variant thereof is intended to cover the non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the sentence “including a…” does not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0049] Term explanation:

[0050] SCR: Selective Catalytic Reduction, selective catalytic reducer, using NH3 as reducing agent;

[0051] H2SCR: Selective Hydrogen Catalytic Reduction Catalyst, using H2 as reducing agent.

[0052] As known from the background art, the traditional SCR technology is used to treat NOx in the exhaust gas of a vehicle. When the temperature is low, urea crystallization is prone to occur, which reduces the conversion rate of NOx and cannot fully convert NOx in the exhaust gas.

[0053] In addition to using the SCR technology to treat NOx in the exhaust gas, there is also a way of using H2SCR to treat NOx in the exhaust gas. However, this treatment method has low conversion efficiency of NOx at medium and high temperatures, and has a narrow temperature window, and cannot fully convert NOx in the exhaust gas at medium and high temperatures.

[0054] To solve the above problems, the application provides a hydrogen internal combustion engine aftertreatment device and a control method. The input end of the SCR in the hydrogen internal combustion engine aftertreatment device is connected with the output end of the first pipeline and the output end of the second pipeline respectively. The output end of the H2SCR is connected with the input end of the second pipeline. The input end of the H2SCR and the input end of the first pipeline are connected with the intelligent control valve. The intelligent control valve is used for controlling the conduction state of the input end of the H2SCR and the input end of the first pipeline and the exhaust inlet. When the exhaust temperature in the working state information of the hydrogen internal combustion engine aftertreatment device is less than the first preset temperature, the intelligent control valve controls the input end of the H2SCR to be conducted with the exhaust inlet, and the input end of the first pipeline is not conducted with the exhaust inlet. Therefore, the H2SCR is used to convert NOx in the exhaust first, and then the SCR is used to convert NOx in the exhaust. Therefore, under the condition of low temperature, the H2SCR is used to convert NOx in the exhaust, thereby solving the problems of low-temperature urea crystallization and low NOx conversion rate, and effectively improving the NOx conversion rate in the exhaust at low temperature. When the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls the input end of the H2SCR to be not conducted with the exhaust inlet, and the input end of the first pipeline is conducted with the exhaust inlet. Therefore, under the condition of high temperature, the SCR is directly used to convert NOx in the exhaust. Therefore, under different temperatures, different NOx conversion modes are used to improve the NOx conversion rate and reduce the NOx emission of automobile exhaust.

[0055] The application can be used in many general or special-purpose computing device environments or configurations. For example: personal computers, server computers, handheld or portable devices, tablet-type devices, multiprocessor devices, distributed computing environments that include any of the above devices or devices, and the like.

[0056] Reference Figure 1 A structure schematic diagram of a hydrogen internal combustion engine aftertreatment device provided by the embodiment of the application is provided, and the specific description is as follows:

[0057] The hydrogen internal combustion engine aftertreatment device comprises: a heat dissipation device 15, a selective catalytic reducer SCR 5 taking NH3 as a reducing agent, and a selective hydrogen catalytic reduction catalyst H2SCR 4 taking H2 as a reducing agent.

[0058] The input end of the SCR 5 is connected with the output end of the first pipeline 3 and the output end of the second pipeline 2 respectively.

[0059] The output end of the H2SCR 4 is connected with the input end of the second pipeline 2, and the H2SCR 5 is provided with heat dissipation fins 11.

[0060] The input end of the H2SCR 4 and the input end of the first pipeline 3 are connected with the intelligent control valve 10.

[0061] The intelligent control valve 10 is used for controlling the conduction state of the input end of the H2SCR and the input end of the first pipeline 3 and the exhaust inlet 1.

[0062] The heat dissipation device 15 is used for dissipating heat for the H2SCR 5; wherein the heat dissipation device 15 comprises a wind regulator 13, a gas guide pipeline 12 and an air outlet 14; further, the wind regulator 13 can be a temperature regulating grille; the wind regulator is used for adjusting the air flow of the heat dissipation device blowing to the H2SCR 4, and the air flow of the heat dissipation device blowing to the H2SCR 4 is adjusted by controlling the opening degree of the wind regulator.

[0063] Further, the first NOx sensor 9 and the temperature sensor 8 are arranged at the exhaust inlet 1; the first NOx sensor 9 is used for detecting the NOx content in the exhaust gas at the exhaust inlet; the temperature sensor 8 is used for detecting the temperature of the exhaust gas at the exhaust inlet. The input end of the SCR 5 is provided with a urea nozzle 7; the output end of the SCR 5 is provided with a second NOx sensor 6; the second NOx sensor 6 is used for detecting the NOx content in the exhaust gas at the output end of the SCR. Preferably, the first NOx sensor can be regarded as a primary NOx sensor, and the second NOx sensor can be regarded as a tail NOx sensor.

[0064] Referring to Figure 2 A flowchart of a hydrogen internal combustion engine aftertreatment device processing method provided by the embodiment is shown in the figure, and the specific description is as follows:

[0065] S201, real-time collection of working state information of the hydrogen internal combustion engine aftertreatment device.

[0066] The working state information includes but is not limited to the information collected by each sensor in the hydrogen internal combustion engine aftertreatment device and the working parameters of each device of the hydrogen internal combustion engine aftertreatment device; for example, the exhaust temperature collected by the temperature sensor, the NOx value in the untreated exhaust gas collected by the first NOx sensor (which can be understood as the primary NOx value), and the NOx value in the exhaust gas output from the SCR collected by the second NOx sensor (which can be understood as the tail NOx).

[0067] S202, judging whether the exhaust temperature in the working state information is greater than or equal to a first preset temperature; when the exhaust temperature in the working state information is less than the first preset temperature, executing S203; when the exhaust temperature in the working state information is greater than or equal to the first preset temperature, executing S204.

[0068] The first preset temperature can be set according to actual needs; for example, the first preset temperature can be set to 250℃; preferably, when the first preset temperature is set, the lowest temperature at which the SCR has a NOx conversion efficiency close to 100% can be set.

[0069] Therefore, when the exhaust temperature is less than the first preset temperature, the H2SCR is used to treat the NOx, so that the conversion rate of the NOx in the exhaust gas at the working temperature not suitable for the SCR can be improved.

[0070] S203, control the exhaust gas to be treated to flow through the selective hydrogen catalytic reduction catalyst H2SCR in the hydrogen internal combustion engine aftertreatment device first, then flow through the selective catalytic reduction device SCR in the hydrogen internal combustion engine aftertreatment device with NH3 as the reducing agent, and use the preset low-temperature exhaust treatment strategy to treat the NOx in the exhaust gas by using the H2SCR and the SCR.

[0071] In the embodiments provided in the present application, the intelligent control valve is opened, so that the exhaust inlet is connected with the input end of the H2SCR through the intelligent control valve, the exhaust inlet is not connected with the input end of the first pipeline, the gas flow of the first pipeline is cut off, the exhaust of the exhaust inlet 1 passes through the H2SCR and the second pipeline, and then flows to the SCR.

[0072] When the exhaust gas passes through the H2SCR, the H2SCR treats the NOx in the exhaust gas, and the reaction of the treatment of the NOx by the H2SCR is as follows:

[0073] 4H2+2NO+O2 → N2+4H2O (1)

[0074] 2H2+O2 → 2H2O (2)

[0075] Further, in the process of using the low-temperature exhaust treatment strategy, using the H2SCR and the SCR to treat the NOx in the exhaust gas, the urea nozzle does not spray urea, and the conversion cost of the NOx is reduced. The conversion rate of the H2SCR to the NOx is high at a low temperature, and therefore, the H2SCR is used to convert the NOx in the exhaust gas at a low temperature, and the problems of the urea crystallization of the SCR at a low temperature and the low conversion efficiency of the NOx are solved.

[0076] Further, under the premise that the exhaust temperature in the working state information is less than the first preset temperature, the process of using the low-temperature exhaust treatment strategy, using the H2SCR and the SCR to treat the NOx in the exhaust gas is as shown in Figure 3 The specific description is as follows:

[0077] S301, judge whether the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, when the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, execute S302; when the exhaust temperature in the working state information is greater than the second preset temperature in the low-temperature exhaust treatment strategy, execute S305.

[0078] It should be noted that the second preset temperature is less than the first preset temperature, and the second preset temperature can be set according to actual needs. For example, the second preset temperature can be set to 200 DEG C.

[0079] S302, determine whether the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value in the low-temperature exhaust treatment strategy; when the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value, execute S303; when the tail exhaust NOx value in the working state information is greater than the NOx limit value, execute S304.

[0080] The NOx limit value in the low-temperature exhaust treatment strategy can be understood as the tail exhaust NOx target value of the hydrogen internal combustion engine aftertreatment device.

[0081] The tail exhaust NOx value in the working state information is detected by the second NOx sensor. Here, the tail exhaust NOx can be understood as the NOx value of the actual tail exhaust gas of the hydrogen internal combustion engine aftertreatment device.

[0082] S303, using H2SCR to reduce the NOx in the exhaust gas, and using SCR to treat the NOx in the exhaust gas after H2SCR treatment.

[0083] S304, before the exhaust gas to be treated flows to the H2SCR, hydrogen is supplemented to the exhaust gas, the NOx in the exhaust gas after hydrogen supplementation is treated by using H2SCR, and the NOx in the exhaust gas after H2SCR treatment is treated by using SCR.

[0084] When the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value, it indicates that the amount of unburned H2 in the exhaust gas is sufficient for treating the NOx in the exhaust gas, and additional hydrogen supplementation is not required; when the tail exhaust NOx value in the working state information is greater than the NOx limit value, the NOx emission will be close to the emission limit value, and at this time it indicates that the amount of unburned H2 in the exhaust gas is insufficient for treating the NOx, and additional H2 is required.

[0085] The process of supplementing hydrogen to the exhaust gas is as follows: obtaining a hydrogen supplementation parameter; determining a hydrogen supplementation value using the hydrogen supplementation parameter, and controlling the injection amount of hydrogen injected by a preset hydrogen injector into the exhaust gas according to the hydrogen supplementation value; further, the hydrogen supplementation parameter includes but is not limited to the difference between the tail exhaust NOx value and the NOx limit value, the temperature value of the H2SCR, and the space velocity; based on the hydrogen supplementation parameter, determine the requested supplementation value, i.e. the required additional H2 demand value, from the pre-calibrated H2 demand value MAP; control the injection amount of hydrogen injected by the hydrogen injection device, thereby supplementing hydrogen to the exhaust gas. Further, the hydrogen injection device can be arranged above the engine cylinder, i.e. a small amount of hydrogen is directly injected into the combustion chamber during the exhaust stroke, and the hydrogen will be pushed out of the cylinder by the exhaust process and flow into the exhaust tailpipe. The hydrogen injector can also be arranged at the front end of the intelligent control valve.

[0086] Thus, by supplementing hydrogen to the exhaust gas, the H2SCR can fully convert the NOx in the exhaust gas, thereby improving the conversion rate of NOx.

[0087] S305, based on the preset heat dissipation strategy, controlling the heat dissipation device in the hydrogen internal combustion engine aftertreatment device to perform heat dissipation treatment on the H2SCR, and making the exhaust gas pass through the H2SCR for treatment, and then using the SCR to treat the exhaust gas.

[0088] It should be noted that when the exhaust gas temperature is greater than the second preset temperature and less than the first preset temperature, S305 is executed, that is, based on the preset heat dissipation strategy, the heat dissipation device in the hydrogen internal combustion engine aftertreatment device is controlled to perform heat dissipation treatment on the H2SCR, specifically: controlling the opening of the wind regulator in the heat dissipation device to be 100%, so that the gas for heat dissipation passes through the wind regulator to perform heat dissipation treatment on the H2SCR, and adjusting the opening of the wind regulator according to the temperature change of the H2SCR. Preferably, the temperature of the H2SCR here can be the average temperature, or the temperature detected at the moment.

[0089] For example, when the exhaust gas temperature is greater than the second preset temperature and less than the first preset temperature, the opening of the temperature regulating grille is 100%, that is, the temperature regulating grille is fully opened, and the specific implementation process is as follows: when the temperature of the H2SCR is greater than the second preset temperature and less than the first preset temperature, the opening of the temperature regulating grille is 100%, that is, the temperature regulating grille is fully opened, and the specific implementation process is as follows: Figure 4 , which is an example diagram of the temperature regulating grille fully opened provided by the embodiment of the present application. Further, after the heat dissipation of the H2SCR starts, the opening of the temperature regulating grille is adjusted according to the temperature change of the H2SCR, specifically: when the temperature of the H2SCR is less than the second preset temperature and greater than the third preset temperature, the temperature regulating grille is partially opened, that is, the opening of the temperature regulating grille is not 100%, such as Figure 1 , which is an example diagram of the temperature regulating grille partially opened provided by the embodiment of the present application; when the temperature of the H2SCR is less than or equal to the third preset temperature, the opening of the temperature regulating grille is zero, that is, the temperature regulating grille is fully closed, and the specific implementation process is as follows: Figure 5 , which is an example diagram of the temperature regulating grille fully closed provided by the embodiment of the present application; the third preset temperature can be set according to actual needs.

[0090] Preferably, the opening of the temperature regulating grille can be adjusted according to the temperature change of the H2SCR, and the specific implementation process is as follows: Figure 6 , which is an example diagram of the opening adjustment of the temperature regulating grille provided by the embodiment of the present application, wherein T3 is the third preset temperature, T2 is the second preset temperature, T1 is the first preset temperature, and Tm is the temperature of the H2SCR. As can be seen from the figure, the opening of the temperature regulating grille can be linearly adjusted.

[0091] In the embodiments provided in the present application, when the temperature of the H2SCR is less than or equal to the third preset temperature, the temperature regulating grille is fully closed, at this time, the heat dissipation device no longer cools the H2SCR, preventing the H2SCR from being cooled too much, so that the H2SCR can be in the temperature range of the highest NOx conversion rate, and the time of the H2SCR in the temperature range of the highest NOx conversion rate can be prolonged, thereby improving the conversion rate of NOx.

[0092] In the scheme provided in the embodiments of the present application, when the exhaust gas temperature is in the temperature range constituted by the second preset temperature and the first preset temperature, as the exhaust gas temperature rises, the conversion efficiency of the H2SCR for NOx gradually decreases, but the conversion efficiency of the SCR for NOx has not reached the highest efficiency region at this temperature range, at this time, the H2SCR can be used to continue to convert NOx, and the heat dissipation device can be used to perform heat dissipation treatment on the H2SCR, thereby reducing the temperature of the H2SCR, so as to ensure that the H2SCR works in the highest efficiency temperature range.

[0093] Preferably, after the heat dissipation device is turned on, when the temperature of the H2SCR is less than or equal to the second preset temperature, during the process of the H2SCR in treating NOx in the exhaust gas, it is necessary to detect whether hydrogen needs to be supplemented, specifically, whether the tail NOx value is greater than the NOx limit value is detected, when the tail NOx value is greater than the NOx limit value, it is determined that hydrogen needs to be supplemented, the determination method of the amount of hydrogen supplement is referred to the description above, which will not be repeated here, when the tail NOx value is less than or equal to the NOx limit value, it is determined that hydrogen does not need to be supplemented.

[0094] S204, control the exhaust gas to be treated not to flow through the H2SCR, directly flow through the SCR, and use a preset high-temperature exhaust gas treatment strategy to control the preset urea nozzle to spray urea and make the SCR treat NOx in the exhaust gas.

[0095] In the embodiments provided in the present application, the intelligent control valve is closed, so that the intelligent control valve controls the exhaust gas inlet and the input end of the H2SCR not to be conductive, the exhaust gas inlet and the input end of the first pipeline are conductive, the gas flow of the H2SCR is cut off, so that all the exhaust gas of the exhaust gas inlet flows to the SCR through the first pipeline.

[0096] Further, the heat dissipation device is in a closed state.

[0097] The process of controlling the preset urea nozzle to spray urea is as follows: obtaining urea supplement parameters; using the urea supplement parameters to determine the urea injection amount, and controlling the urea nozzle to spray urea according to the urea injection amount. The urea supplement parameters include but are not limited to the original NOx value, the exhaust gas temperature and the SCR space velocity; the urea injection amount is determined according to the original NOx value, the exhaust gas temperature value T and the SCR space velocity in the ammonia storage closed loop MAP, and then the urea nozzle is closed loop controlled to spray urea.

[0098] In the scheme provided by the embodiment of the application, the intelligent control valve in the hydrogen internal combustion engine aftertreatment device is connected with the exhaust inlet, the input end of the H2SCR and the input end of the first pipeline respectively, the output end of the first pipeline is connected with the SCR, and the output end of the H2SCR is connected with the SCR through the second pipeline; the intelligent control valve is used to control the conduction state of the input end of the H2SCR and the input end of the first pipeline and the exhaust inlet; when the exhaust temperature of the hydrogen internal combustion engine aftertreatment device is less than the first preset temperature, the intelligent control valve controls the input end of the H2SCR to be conducted with the exhaust inlet, and the input end of the first pipeline is not conducted with the exhaust inlet; in the case of low temperature, the H2SCR is used to convert NOx in the exhaust gas, the problem of low temperature urea crystallization is solved, the conversion rate of NOx is low, and the conversion rate of NOx in the exhaust gas at low temperature is improved; when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls the input end of the H2SCR to be not conducted with the exhaust inlet, and the input end of the first pipeline is conducted with the exhaust inlet; thus, in the case of high temperature, the SCR is used to convert NOx in the exhaust gas. Different NOx conversion methods are used at different temperatures, the conversion rate of NOx is improved, and the NOx emission of automobile exhaust is reduced.

[0099] Reference Figure 7 Another flow chart of the control method of the hydrogen internal combustion engine aftertreatment device provided by the embodiment of the application is provided, and specific descriptions are as follows:

[0100] The working state information of the hydrogen internal combustion engine aftertreatment device is collected, and the related description of the working state information is referred to the foregoing description, which will not be repeated here. Based on the exhaust temperature in the working state information, it is judged whether the exhaust temperature is less than or equal to the second preset temperature; when the exhaust temperature is less than or equal to the second preset temperature, the intelligent control valve controls the exhaust inlet to be conducted with the H2SCR, and the exhaust inlet is not conducted with the first pipeline, and the exhaust gas flows to the SCR after being treated by the H2SCR; in the process of treating NOx in the exhaust gas by the H2SCR, it is judged whether the tail exhaust NOx value is less than the NOx limit value; when the tail exhaust NOx value is less than the NOx limit value, the hydrogen injector is controlled to spray hydrogen, and the process of determining the amount of hydrogen sprayed by the hydrogen injector is referred to the foregoing content, which will not be repeated here.

[0101] When the exhaust temperature is greater than the second preset temperature, it is determined whether the exhaust temperature is greater than or equal to the first preset temperature, and when the exhaust temperature is greater than or equal to the first preset temperature, the intelligent control valve controls the exhaust inlet to be conductive to the H2SCR and non-conductive to the first pipeline, the exhaust flows to the SCR after being treated by the H2SCR, and the heat dissipation device is controlled to dissipate heat for the H2SCR. The process of controlling the heat dissipation device to dissipate heat for the H2SCR is as follows: it is determined whether the temperature of the H2SCR is less than the second preset temperature, when the temperature of the H2SCR is not less than the second preset temperature, the temperature regulating grid of the heat dissipation device is fully opened; when the temperature of the H2SCR is less than the second preset temperature, it is determined whether the temperature of the H2SCR is less than or equal to the third preset temperature, and it is determined whether the tail exhaust NOx value is less than the NOx limit value; when the temperature of the H2SCR is less than or equal to the third preset temperature, the temperature regulating grid is fully closed; when the temperature of the H2SCR is greater than the third preset temperature, the temperature regulating grid is partially opened; further, when it is determined that the tail exhaust NOx value is less than the NOx limit value, the hydrogen injector is controlled to inject hydrogen; when it is determined that the tail exhaust NOx value is not less than the NOx limit value, it is determined that hydrogen is not needed to be supplemented. Preferably, the third preset temperature is less than the second preset temperature.

[0102] Further, the control method provided by the application is real-time, so that the strategy applied to the conversion of NOx in the exhaust gas can be adjusted in time. In the scheme provided by the application, the aftertreatment device and the control method thereof are provided, which combines the advantages of the two NOx treatment methods of high NOx conversion efficiency of H2SCR at low temperature and high NOx conversion efficiency of SCR at medium-high temperature, and combines the H2SCR temperature control part, so that the NOx emission treatment capacity of the hydrogen internal combustion engine tail gas is maximized, the risk of urea crystallization of SCR at low temperature is eliminated, high-efficiency NOx reduction of hydrogen internal combustion engine tail gas is achieved in a wide exhaust temperature range, the NOx emission problem of the hydrogen internal combustion engine is solved, the structure is simple, and the practicability is strong.

[0103] The hydrogen internal combustion engine aftertreatment device provided by the application can combine the high NOx conversion efficiency of H2SCR at low temperature and the high-efficiency NOx conversion zone of SCR at medium-high temperature, eliminate the risk of urea crystallization of SCR at low temperature, achieve high-efficiency NOx reduction of hydrogen internal combustion engine tail gas in a wide exhaust temperature range, solve the NOx emission problem of the hydrogen internal combustion engine, the structure is simple, and the practicability is strong; further, the hydrogen internal combustion engine aftertreatment device can be applied to an engine to reduce the NOx content in the exhaust gas of the engine.

[0104] It should be noted that the information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or authorized by all parties, and the collection, use and processing of related data need to comply with relevant laws, regulations and standards of relevant countries and regions.

[0105] The specific implementation process of each of the above embodiments and its derivatives are within the protection scope of the present application.

[0106] Each of the embodiments in the specification is described in a progressive manner, and the same or similar parts between each embodiment can be referred to each other. Each embodiment focuses on the difference from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, it is described more simply, and the relevant part can be referred to the part of the method embodiment. The above described system and system embodiment are only illustrative, and the units described as separate components can be or can not be physically separated, and the components displayed as units can be or can not be physical units, that is, they can be located in one place or distributed on multiple network units. Part or all of the modules can be selected to achieve the purpose of the embodiment scheme according to the actual needs. Those skilled in the art can understand and implement without creative labor.

[0107] The skilled person can further realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized by electronic hardware, computer software or a combination of both. In order to clearly illustrate the interchangeability of hardware and software, the components and steps of each example have been described in the above description. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical scheme. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0108] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to the embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method of controlling a hydrogen internal combustion engine aftertreatment device, characterized by, The method comprises: Real-time acquisition of working state information of the hydrogen internal combustion engine aftertreatment device; When the exhaust temperature in the working state information is less than a first preset temperature, controlling the exhaust to be treated to flow through a selective hydrogen catalytic reduction catalyst H2SCR using H2 as a reducing agent in the hydrogen internal combustion engine aftertreatment device first, then flow through a selective catalytic reduction device SCR using NH3 as a reducing agent in the hydrogen internal combustion engine aftertreatment device, and using a preset low-temperature exhaust treatment strategy to treat NOx in the exhaust using the H2SCR and the SCR; When the exhaust temperature in the working state information is greater than or equal to the first preset temperature, controlling the exhaust to be treated to not flow through the H2SCR, directly flow through the SCR, and using a preset high-temperature exhaust treatment strategy to control a preset urea nozzle to spray urea and make the SCR treat NOx in the exhaust; The use of the preset low-temperature exhaust treatment strategy to treat NOx in the exhaust using the H2SCR and the SCR comprises: Judging whether the exhaust temperature in the working state information is less than or equal to a second preset temperature in the low-temperature exhaust treatment strategy; When the exhaust temperature in the working state information is less than or equal to the second preset temperature in the low-temperature exhaust treatment strategy, judging whether a tail exhaust NOx value in the working state information is less than or equal to a NOx limit value in the low-temperature exhaust treatment strategy; When the tail exhaust NOx value in the working state information is less than or equal to the NOx limit value, using the H2SCR to reduce NOx in the exhaust and using the SCR to treat NOx in the exhaust treated by the H2SCR; When the tail exhaust NOx value in the working state information is greater than the NOx limit value, supplementing hydrogen to the exhaust before the exhaust to be treated flows to the H2SCR, using the H2SCR to treat NOx in the exhaust supplemented with hydrogen, and using the SCR to treat NOx in the exhaust treated by the H2SCR.

2. The method of claim 1, wherein, The supplementing of hydrogen to the exhaust comprises: Obtaining a hydrogen supplement parameter; Using the hydrogen supplement parameter to determine a hydrogen supplement value, and controlling a preset hydrogen injector to spray hydrogen to the exhaust according to the hydrogen supplement value.

3. The method of claim 1, wherein, Further comprising: When the exhaust temperature in the working state information is greater than the second preset temperature in the low-temperature exhaust treatment strategy, based on a preset heat dissipation strategy, controlling a heat dissipation device in the hydrogen internal combustion engine aftertreatment device to perform heat dissipation treatment on the H2SCR, and then using the SCR to treat the exhaust after the exhaust is treated by the H2SCR.

4. The method of claim 3, wherein, The control of the heat dissipation device in the hydrogen internal combustion engine aftertreatment device to perform heat dissipation treatment on the H2SCR based on the preset heat dissipation strategy comprises: Controlling an opening degree of an air flow regulator in the heat dissipation device to be 100%, so that the gas for heat dissipation performs heat dissipation treatment on the H2SCR after passing through the air flow regulator, and adjusting the opening degree of the air flow regulator according to a temperature change of the H2SCR.

5. The method of claim 1, wherein, The control preset urea nozzle sprays urea, comprising: Obtaining urea supplement parameters; Using the urea supplement parameters to determine urea injection amount, and controlling the urea nozzle to spray urea according to the urea injection amount.

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