Ammonia gas leakage treatment method and device and hybrid vehicle

Abstract

The invention provides an ammonia gas leakage treatment method and device and a hybrid vehicle. The method comprises the steps that the mass flow rates of nitric oxide before and after the aftertreatment step are obtained respectively, the catalyst utilization rate is determined according to the mass flow rates, the aftertreatment step represents the tail gas treatment step of an engine, and the catalyst utilization rate represents the utilization rate of a catalyst in a selective catalytic reduction device; the current temperature of the selective catalytic reduction device is obtained, and the ammonia gas reserve in the selective catalytic reduction device is determined according to the catalyst utilization rate and the current temperature; and at least under the condition that the ammonia gas storage amount is larger than the preset ammonia gas threshold value and the current temperature is larger than the preset temperature threshold value, the torque of the engine is switched into the first ammonia cleaning torque, and the leakage amount of ammonia gas is reduced. The problem that in the prior art, there is no solution for ammonia leakage in the rapid temperature rising process is solved.

Description

Technical Field

[0001] The present application relates to the technical field of gas leakage treatment, and in particular, to a method, device, computer-readable storage medium and hybrid vehicle for treating ammonia leakage. Background Art

[0002] Nitrogen oxides (NOx) are key pollutants emitted by diesel engines. With the further tightening of emission regulations, SCR (Selective Catalytic Reduction, SCR for short) is widely used to control NOx emissions. In the SCR carrier, NH3 decomposed by urea undergoes catalytic reduction reaction with NOx in the exhaust gas. Most of the NH3 is reacted, and the unreacted NH3 is stored on the SCR carrier. When the urea injection amount is insufficient or the urea injection is stopped, the NH3 stored in the SCR carrier can continue to react with NOx in the exhaust gas to reduce emissions. The ammonia storage capacity of the SCR carrier is related to the temperature of the SCR carrier. The ammonia storage capacity is stronger when the temperature is low. As the temperature rises, the ammonia storage capacity gradually decreases. In particular, when the carrier temperature rises sharply, the stored ammonia in the SCR carrier will quickly escape. The ASC (Ammonia Slip Catalyst, ASC for short) cannot completely oxidize the released NH3, resulting in some NH3 being identified and measured by the downstream NOx sensor, causing emissions to exceed the standard and reporting an over 1.2 fault.

[0003] At present, many models have ammonia leakage during the temperature rise process, especially light products, which have small post-processing volume and are sensitive to the operating boundary. Ammonia leakage during the temperature rise process leads to excessive emissions and a high failure rate of more than 1.2. The existing technology does not propose any solution to the ammonia leakage problem during the rapid temperature rise process. Summary of the invention

[0004] The main purpose of the present application is to provide a method, device, computer-readable storage medium and hybrid vehicle for processing ammonia leakage, so as to at least solve the problem that there is a lack of a solution to ammonia leakage during a rapid temperature increase process in the prior art.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a method for processing ammonia leakage is provided, which is applied to a hybrid power system, wherein the hybrid power system at least includes an engine, an electric motor and a power battery, and the method for processing ammonia leakage includes: respectively obtaining a mass flow rate of nitrogen oxides before a post-processing step and a mass flow rate of nitrogen oxides after the post-processing step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-processing step represents an exhaust gas processing step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer; obtaining a current temperature of the selective catalytic reducer, and determining an ammonia reserve in the selective catalytic reducer according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, switching the torque of the engine to a first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power state of the power battery.

[0006] Optionally, determining the ammonia reserves in the selective catalytic reduction device according to the catalyst utilization and the current temperature includes: obtaining a one-to-one mapping relationship among the catalyst utilization, the current temperature and the predicted ammonia reserves; determining the predicted ammonia reserves corresponding to the catalyst utilization and the current temperature according to the one-to-one mapping relationship to obtain the ammonia reserves.

[0007] Optionally, at least when the ammonia reserves are greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia-clearing torque, including: obtaining a historical temperature of the selective catalytic reduction device, and calculating a temperature difference between the current temperature and the historical temperature, wherein the historical temperature represents the temperature at a moment before the current moment corresponding to the current temperature; when the ammonia reserves are greater than a preset ammonia threshold, the current temperature is greater than a preset temperature threshold, the temperature difference is a positive value, and the temperature difference is greater than a preset temperature difference, it is determined that the engine is in a high-risk state for ammonia leakage, and the torque of the engine is switched to the first ammonia-clearing torque.

[0008] Optionally, switching the torque of the engine to a first ammonia-clearing torque includes: obtaining a current battery power state of the power battery; and switching the torque of the engine to the first ammonia-clearing torque when the current battery power state indicates that the battery power of the power battery is greater than a preset power threshold.

[0009] Optionally, after switching the torque of the engine to the first ammonia-clearing torque, the method further includes: obtaining a total required torque; calculating a difference between the total required torque and the first ammonia-clearing torque to obtain a second ammonia-clearing torque of the motor, and switching the torque of the motor to the second ammonia-clearing torque, wherein the total required torque is greater than the first ammonia-clearing torque.

[0010] Optionally, the mass flow rate of nitrogen oxides before and after post-treatment is obtained, and the catalyst utilization rate is determined according to the first mass flow rate and the second mass flow rate, including: calculating the difference between the first mass flow rate and the second mass flow rate to obtain the conversion mass flow rate, and determining the catalyst utilization rate according to the conversion mass flow rate.

[0011] Optionally, the catalyst utilization rate is determined according to the conversion mass flow rate, including: obtaining a conversion coefficient, calculating the product of the conversion mass flow rate and the conversion coefficient, and obtaining a catalyst consumption, wherein the conversion coefficient characterizes the conversion rate between the nitrogen oxides and the catalyst; obtaining a catalyst injection amount, calculating a ratio of the catalyst consumption to the catalyst injection amount, and obtaining the catalyst utilization rate.

[0012] According to another aspect of the present application, an ammonia leakage processing device is provided, which is applied to a hybrid power system, wherein the hybrid power system includes at least an engine, an electric motor and a power battery, and the ammonia leakage processing device includes: a first determination unit, which is used to respectively obtain the mass flow rate of nitrogen oxides before a post-treatment step and the mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determine a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer; a second determination unit, which is used to obtain a current temperature of the selective catalytic reducer, and determine an ammonia reserve in the selective catalytic reducer according to the catalyst utilization rate and the current temperature; a switching unit, which is used to switch the torque of the engine to a first ammonia clearing torque to reduce the leakage of ammonia, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power state of the power battery.

[0013] According to another aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute any one of the methods for processing ammonia leakage.

[0014] According to another aspect of the present application, a hybrid vehicle is provided, comprising: a hybrid system, the hybrid system comprising at least an engine, an electric motor and a power battery; a controller, comprising one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing any one of the ammonia leakage processing methods.

[0015] Applying the technical solution of the present application, the mass flow rate of nitrogen oxides before and after the post-treatment step is obtained respectively, and the catalyst utilization rate is determined according to the mass flow rate, wherein the post-treatment represents the exhaust gas treatment of the engine, and the catalyst utilization rate represents the utilization rate of the catalyst in the selective catalytic reducer; the current temperature of the selective catalytic reducer is obtained, and the ammonia reserve in the selective catalytic reducer is determined according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, the torque of the engine is switched to the first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is the torque automatically distributed according to the battery power state of the power battery. Compared with the prior art, the problem of ammonia leakage of the engine during the rapid heating process cannot be solved. The present application predicts the ammonia reserve by the catalyst utilization rate, and controls the torque of the engine according to the ammonia reserve to reduce the leakage of ammonia. Therefore, it can solve the problem of the lack of ammonia leakage solution in the prior art during the rapid heating process, and achieve the effect of reducing ammonia leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0017] Figure 1 A hardware structure block diagram of a mobile terminal for executing a method for processing ammonia leakage provided in an embodiment of the present application is shown;

[0018] Figure 2 A schematic flow chart of a method for treating ammonia leakage provided in an embodiment of the present application is shown;

[0019] Figure 3 A schematic structural diagram of a hybrid vehicle provided by an embodiment of the present application is shown;

[0020] Figure 4 A schematic flow chart of a specific method for treating ammonia leakage provided in an embodiment of the present application is shown;

[0021] Figure 5 A schematic diagram of a relationship curve between SCR carrier temperature and conversion efficiency provided in an embodiment of the present application is shown;

[0022] Figure 6 A structural block diagram of an ammonia leakage processing device provided in an embodiment of the present application is shown.

[0023] The above drawings include the following reference numerals:

[0024] 102, processor; 104, memory; 106, transmission device; 108, input and output devices. DETAILED DESCRIPTION

[0025] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of this application.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device comprising a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0028] For the convenience of description, some nouns or terms involved in the embodiments of the present application are explained below:

[0029] Hybrid system: An electric drive system (i.e., electric motor and power battery) is added to the traditional car. The engine and electric motor can drive the wheels independently, or work at the same time to drive the car together. When the power battery is low on power, the engine can also drive the electric motor to charge the battery.

[0030] The post-processing step is the exhaust gas treatment step of the engine, which generally includes the following steps:

[0031] DOC: Diesel Oxidation Catalyst, referred to as DOC, generally uses metal or ceramic as the catalyst carrier, and the main active components in the coating are precious metals and rare metals such as platinum and palladium. When the exhaust gas of the diesel engine passes through the catalyst, HC (hydrocarbon) and CO (carbon monoxide) react chemically with the oxygen in the exhaust gas to generate pollution-free H2O and CO2. DOC achieves the purpose of purifying HC and CO in the exhaust gas;

[0032] DPF: Diesel Particulate Filter, referred to as DPF, can filter and capture PM (particulate matter) in the exhaust gas, which can reduce PM (particulate matter) in the exhaust gas, and the filtering effect can usually reach 70%-90%. SCR is mainly used to remove NOx (nitrogen oxides) in the exhaust gas. Using urea as a reducing agent, under the reduction effect of a selective catalyst, NOx (nitrogen oxides) in the exhaust gas are reduced to nitrogen and water;

[0033] SCR: Selective Catalytic Reduction, referred to as SCR, its main function is to use NH3 decomposed by urea to carry out catalytic reduction reaction with NOx in exhaust gas to reduce the emission level of exhaust NOx to meet regulatory requirements.

[0034] SCR: Selective Catalytic Reduction, or SCR for short, is mainly used to utilize NH3 decomposed from urea to carry out catalytic reduction reaction with NOx in exhaust gas. Hybrid system: An electric drive system (i.e., electric motor and power battery) is added to the traditional car. The engine and electric motor can drive the wheels independently or work at the same time to drive the car together. When the power battery is low on power, the engine can also drive the electric motor to charge the battery.

[0035] ASC: Ammonia Slip Catalyst, ASC for short, is a catalytic converter that oxidizes the escaped ammonia (NH3) into nitrogen (N2), thereby reducing the pollution to air quality. It is one of the necessary post-treatment catalytic technologies for ultra-low emission diesel vehicles.

[0036] As introduced in the background technology, the prior art lacks a solution to ammonia leakage during a rapid temperature increase. To address the problem of lack of a solution to ammonia leakage during a rapid temperature increase, the embodiments of the present application provide a method, device, computer-readable storage medium and hybrid vehicle for processing ammonia leakage.

[0037] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0038] The method embodiments provided in the embodiments of the present application can be executed in a mobile terminal, a computer terminal or a similar computing device. Taking running on a mobile terminal as an example, Figure 1 FIG. 1 is a hardware structure block diagram of a mobile terminal for a method for processing ammonia leakage according to an embodiment of the present invention. Figure 1 As shown, the mobile terminal may include one or more ( Figure 1 Only one is shown in the figure) a processor 102 (the processor 102 may include but is not limited to a processing device such as a microprocessor MCU or a programmable logic device FPGA) and a memory 104 for storing data, wherein the mobile terminal may also include a transmission device 106 and an input / output device 108 for communication functions. It can be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the mobile terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0039] The memory 104 can be used to store computer programs, for example, software programs and modules of application software, such as the computer program corresponding to the method for treating ammonia leakage in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the computer program stored in the memory 104, that is, the above method is implemented. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories can be connected to the mobile terminal via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and a combination thereof. The transmission device 106 is used to receive or send data via a network. The above-mentioned specific network example may include a wireless network provided by a communication provider of the mobile terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 may be a radio frequency (RF) module, which is used to communicate with the Internet wirelessly.

[0040] In this embodiment, a method for processing ammonia leakage running on a mobile terminal, a computer terminal or a similar computing device is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0041] Figure 2 FIG. 1 is a flow chart of a method for treating ammonia leakage according to an embodiment of the present application. Figure 2 As shown, the method is applied to a hybrid power system, wherein the hybrid power system at least includes an engine, an electric motor and a power battery, and the method includes the following steps:

[0042] Step S201, respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer;

[0043] Specifically, the catalyst in SCR (Selective Catalytic Reduction) is generally ammonia. The ammonia reserve in the SCR carrier can be predicted based on the catalyst utilization rate, that is, the actual utilization rate of ammonia, which is achieved in the following way: the NOx mass flow rate before the post-treatment step is subtracted from the NOx mass flow rate after the post-treatment step to obtain the NOx mass flow rate converted by the post-treatment; the actual urea consumption flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate, that is, the above-mentioned catalyst utilization rate.

[0044] Step S202, obtaining the current temperature of the selective catalytic reduction device, and determining the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature;

[0045] Specifically, the ammonia reserves can be predicted based on the catalyst utilization rate and the current temperature of the SCR. Theoretically, when the SCR carrier, i.e., the selective catalytic reducer, has no ammonia reserves, the urea utilization rate is determined by the conversion efficiency, and the SCR conversion efficiency is directly related to the temperature of the SCR carrier. The two are a relatively definite relationship curve. However, when there are ammonia reserves in the SCR carrier, the stored ammonia will also participate in the conversion of NOx, thereby increasing the urea utilization rate. Therefore, the ammonia reserves of the SCR carrier can be predicted based on the actual urea utilization rate and the SCR carrier temperature. When the temperature is constant, the higher the actual urea utilization rate, the higher the level of ammonia stored in the carrier.

[0046] Step S203, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia clearing torque to reduce ammonia leakage, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

[0047] Specifically, the ammonia leakage risk state is identified based on the predicted ammonia reserve and SCR temperature: the ammonia reserve is compared with the preset ammonia threshold. If it is greater than the preset temperature threshold, the carrier is considered to be in a high ammonia storage state; and when the SCR temperature is greater than the preset temperature threshold, the engine is considered to be in a high temperature state; when at least the above two conditions are met, the SCR carrier temperature needs to be controlled in time to reduce ammonia leakage. Specifically, the engine torque can be switched to the first ammonia clearing torque, under which the engine exhaust temperature is relatively low, so as to achieve the effect of reducing the after-treatment exhaust temperature.

[0048] Through this embodiment, the mass flow of nitrogen oxides before and after the post-treatment step is obtained respectively, and the catalyst utilization rate is determined according to the mass flow rate, wherein the post-treatment represents the exhaust gas treatment of the engine, and the catalyst utilization rate represents the utilization rate of the catalyst in the selective catalytic reducer; the current temperature of the selective catalytic reducer is obtained, and the ammonia reserve in the selective catalytic reducer is determined according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, the torque of the engine is switched to the first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is the torque automatically distributed according to the battery power state of the power battery. Compared with the problem that the prior art cannot solve the ammonia leakage of the engine during the rapid heating process, the present application predicts the ammonia reserve through the catalyst utilization rate, and controls the torque of the engine according to the ammonia reserve to reduce the leakage of ammonia. Therefore, it can solve the problem of the lack of ammonia leakage solution in the prior art during the rapid heating process, and achieve the effect of reducing ammonia leakage.

[0049] In a specific implementation process, the above step S202 determines the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization and the current temperature, which can be achieved by the following steps: step S2021: obtaining a one-to-one mapping relationship between the catalyst utilization, the current temperature and the predicted ammonia reserve; step S2022: determining the predicted ammonia reserve corresponding to the catalyst utilization and the current temperature according to the one-to-one mapping relationship to obtain the ammonia reserve. The method determines the ammonia reserve through the above steps, so that the current catalyst reserve can be accurately predicted.

[0050] Specifically, since the SCR conversion efficiency is directly related to the temperature of the SCR carrier, that is, the catalyst utilization rate, the current temperature and the predicted ammonia reserves have a one-to-one mapping relationship, which can be expressed in the form of a curve or a table. Therefore, the catalyst utilization rate and the predicted ammonia reserves corresponding to the current temperature can be determined through the one-to-one mapping relationship, that is, the current ammonia reserves.

[0051] In some optional embodiments, the above step S203 switches the engine torque to the first ammonia clearing torque at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, which can be achieved by the following steps: Step S2031: Obtain the historical temperature of the selective catalytic reduction device, and calculate the temperature difference between the current temperature and the historical temperature, wherein the historical temperature represents the temperature of the moment before the current moment corresponding to the current temperature; Step S2032: When the ammonia reserve is greater than the preset ammonia threshold, the current temperature is greater than the preset temperature threshold, the temperature difference is a positive value, and the temperature difference is greater than the preset temperature difference, determine that the engine is in a high risk state of ammonia leakage, and switch the engine torque to the first ammonia clearing torque. The method further determines to switch the engine torque to the first ammonia clearing torque through the above steps, so that the risk of ammonia leakage can be more determined and further measures can be taken to prevent ammonia leakage for a long time.

[0052] In the specific implementation process, in order to further determine the risk of ammonia leakage, it is also necessary to determine the temperature change amplitude of the SCR carrier, that is, to determine whether it is a rapid temperature rise process. This can be determined by whether the temperature difference of the historical temperature at a certain moment before the current moment corresponding to the current temperature is greater than the preset temperature difference. The historical moment can be a moment such as 10 minutes before the current moment. If it is satisfied, it indicates that the engine is in a high risk state of ammonia leakage, and the torque of the engine is switched to the first ammonia removal torque.

[0053] In some optional implementations, the above step S203 switches the torque of the engine to the first ammonia-clearing torque, which can be achieved by the following steps: Step S2033: Acquire the current battery power state of the power battery; Step S2034: When the current battery power state indicates that the battery power of the power battery is greater than a preset power threshold, switch the torque of the engine to the first ammonia-clearing torque. Through the above steps, the method switches the torque when the current SOC (battery power state, State of Charge, SOC for short) of the power battery indicates that the battery power is sufficient, so as to ensure that the engine has sufficient power.

[0054] Specifically, in order to ensure that the engine has sufficient power, the ammonia clearing mode is triggered only when the engine is in a high risk state of ammonia leakage and the current SOC (battery power) is greater than a preset power threshold.

[0055] In some optional embodiments, after the torque of the engine is switched to the first ammonia clearing torque, the method further comprises the following steps: step S204: obtaining the total required torque; step S205: calculating the difference between the total required torque and the first ammonia clearing torque to obtain the second ammonia clearing torque of the motor, and switching the torque of the motor to the second ammonia clearing torque, wherein the total required torque is greater than the first ammonia clearing torque. The method controls the torque of the motor to be converted through the above steps, so that the total torque load torque requirement can be guaranteed.

[0056] In the specific implementation process, the total demand torque is subtracted from the engine set torque in the first ammonia cleanup mode to obtain the set load of the motor in the ammonia cleanup mode, thereby controlling the motor operation. This control method can effectively monitor the risk status of post-treatment ammonia leakage, and when a high risk of ammonia leakage is detected, the exhaust temperature can be effectively reduced by controlling the engine torque, reducing the occurrence of ammonia leakage and reducing the failure rate of exceeding 1.2.

[0057] In some optional embodiments, the above-mentioned step S201 obtains the mass flow rate of nitrogen oxides before and after post-treatment, and determines the catalyst utilization rate based on the first mass flow rate and the second mass flow rate. It can be achieved by the following steps: Step S2011: Calculate the difference between the first mass flow rate and the second mass flow rate to obtain the conversion mass flow rate, and determine the catalyst utilization rate based on the conversion mass flow rate.

[0058] In the specific implementation process, the first NOx mass flow rate is subtracted from the second NOx mass flow rate to obtain the conversion mass flow rate; the actual urea flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate.

[0059] In some optional implementations, step S2012 can be implemented by the following steps: obtaining a conversion coefficient, calculating the product of the conversion mass flow rate and the conversion coefficient, and obtaining a catalyst consumption, wherein the conversion coefficient represents the conversion rate between the nitrogen oxides and the catalyst; obtaining a catalyst injection amount, calculating the ratio of the catalyst consumption to the catalyst injection amount, and obtaining the catalyst utilization rate. The method calculates the catalyst utilization rate through the above steps, so that the catalyst utilization rate can be accurately calculated.

[0060] Specifically, the conversion relationship between NOx and urea can be determined by the conversion coefficient, so the catalyst consumption is obtained by multiplying the conversion mass flow rate and the conversion coefficient; and the catalyst utilization rate can be obtained by the ratio of the catalyst consumption to the catalyst injection amount.

[0061] In order to enable those skilled in the art to more clearly understand the technical solution of the present application, the implementation process of the method for treating ammonia leakage of the present application will be described in detail below in conjunction with specific embodiments.

[0062] Figure 3 A structural schematic diagram of a hybrid vehicle provided by an embodiment of the present application is shown, including an engine, a clutch, a drive motor / generator, a power battery / BMS, a motor controller / MCU and an AMT system. The engine and the motor can drive the wheels independently, or they can work simultaneously to drive the vehicle together. When the power battery is low on power, the engine can also combine with the motor to charge the battery.

[0063] This embodiment relates to a specific method for treating ammonia leakage, such as Figure 4 As shown, the following steps are included:

[0064] Step S1: Subtract the original discharge (before the post-treatment step) NOx mass flow rate from the tail discharge (after the post-treatment step) NOx mass flow rate to obtain the conversion mass flow rate, and calculate the product of the conversion mass flow rate and the NOx and urea conversion coefficients to obtain the actual urea consumption;

[0065] Step S2: Calculate the ratio of the actual urea consumption to the actual urea injection flow rate to obtain the actual urea utilization rate;

[0066] Step S3: obtaining the current temperature of the SCR, searching for the ammonia reserve prediction MAP according to the catalyst utilization rate (actual urea utilization rate) and the current temperature to determine the corresponding predicted ammonia reserve (ammonia reserve);

[0067] Step S4: when the predicted ammonia reserve (ammonia reserve) is greater than a preset ammonia threshold, determining that the engine is in a high ammonia reserve state;

[0068] Step S5: Obtain the SCR historical temperature. When the temperature difference between the current temperature and the historical temperature is greater than the temperature rise threshold and the current temperature is greater than the preset temperature threshold, determine that the engine is in a high ammonia leakage risk state; Figure 5 A schematic diagram of a relationship curve between SCR carrier temperature and conversion efficiency provided in an embodiment of the present application is shown, Figure 5 It can be seen that the SCR conversion efficiency is directly related to the temperature of the SCR carrier, and the two are a relatively definite relationship curve;

[0069] Step S6: obtaining the current SOC. When the current SOC is greater than the power limit, the engine enters the ammonia cleaning mode;

[0070] Step S7: the original engine demand torque based on SOC torque distribution is switched to the engine set torque in the ammonia clearing mode (the first ammonia clearing torque);

[0071] Step S8: The total required torque minus the engine set torque in the ammonia cleaning mode is used to obtain the motor set torque in the ammonia cleaning mode, thereby controlling the motor torque switch to output the motor required load and controlling the motor to operate.

[0072] The present application embodiment also provides a kind of ammonia leakage processing device, it should be noted that the ammonia leakage processing device of the present application embodiment can be used to execute the processing method for ammonia leakage provided by the present application embodiment. The device is used to implement the above-mentioned embodiment and preferred embodiment, and the description has been made and will not be repeated. As used below, the term "module" can implement a combination of software and / or hardware of a predetermined function. Although the device described in the following embodiments is preferably implemented in software, the implementation of hardware, or a combination of software and hardware is also possible and conceived.

[0073] The following is an introduction to the ammonia leakage treatment device provided in the embodiments of the present application.

[0074] Figure 6 Schematic diagram of a device for treating ammonia leakage according to an embodiment of the present application. Figure 6 As shown, the device comprises:

[0075] a first determining unit 10, for respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step, obtaining a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer;

[0076] Specifically, the catalyst in SCR (Selective Catalytic Reduction) is generally ammonia. The ammonia reserve in the SCR carrier can be predicted based on the catalyst utilization rate, that is, the actual utilization rate of ammonia, which is achieved in the following way: the NOx mass flow rate before the post-treatment step is subtracted from the NOx mass flow rate after the post-treatment step to obtain the NOx mass flow rate converted by the post-treatment; the actual urea consumption flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate, that is, the above-mentioned catalyst utilization rate.

[0077] A second determination unit 20 is used to obtain a current temperature of the selective catalytic reduction device, and determine the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature;

[0078] Specifically, the ammonia reserves can be predicted based on the catalyst utilization rate and the current temperature of the SCR. Theoretically, when the SCR carrier, i.e., the selective catalytic reducer, has no ammonia reserves, the urea utilization rate is determined by the conversion efficiency, and the SCR conversion efficiency is directly related to the temperature of the SCR carrier. The two are a relatively definite relationship curve. However, when there are ammonia reserves in the SCR carrier, the stored ammonia will also participate in the conversion of NOx, thereby increasing the urea utilization rate. Therefore, the ammonia reserves of the SCR carrier can be predicted based on the actual urea utilization rate and the SCR carrier temperature. When the temperature is constant, the higher the actual urea utilization rate, the higher the level of ammonia stored in the carrier.

[0079] The switching unit 30 is used to switch the torque of the engine to a first ammonia clearing torque to reduce the leakage of ammonia at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

[0080] Specifically, the ammonia leakage risk state is identified based on the predicted ammonia reserve and SCR temperature: the ammonia reserve is compared with the preset ammonia threshold. If it is greater than the preset temperature threshold, the carrier is considered to be in a high ammonia storage state; and when the SCR temperature is greater than the preset temperature threshold, the engine is considered to be in a high temperature state; when at least the above two conditions are met, the SCR carrier temperature needs to be controlled in time to reduce ammonia leakage. Specifically, the engine torque can be switched to the first ammonia clearing torque, under which the engine exhaust temperature is relatively low, so as to achieve the effect of reducing the after-treatment exhaust temperature.

[0081] Through this embodiment, the mass flow of nitrogen oxides before and after the post-treatment step is obtained respectively, and the catalyst utilization rate is determined according to the mass flow rate, wherein the post-treatment represents the exhaust gas treatment of the engine, and the catalyst utilization rate represents the utilization rate of the catalyst in the selective catalytic reducer; the current temperature of the selective catalytic reducer is obtained, and the ammonia reserve in the selective catalytic reducer is determined according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, the torque of the engine is switched to the first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is the torque automatically distributed according to the battery power state of the power battery. Compared with the problem that the prior art cannot solve the ammonia leakage of the engine during the rapid heating process, the present application predicts the ammonia reserve through the catalyst utilization rate, and controls the torque of the engine according to the ammonia reserve to reduce the leakage of ammonia. Therefore, it can solve the problem of the lack of ammonia leakage solution device during the rapid heating process in the prior art, and achieve the effect of reducing ammonia leakage.

[0082] In a specific implementation process, the second determination unit includes a first acquisition module and a determination module, wherein the first acquisition module is used to acquire a one-to-one mapping relationship between the catalyst utilization rate, the current temperature, and the predicted ammonia reserves; and the determination module is used to determine the predicted ammonia reserves corresponding to the catalyst utilization rate and the current temperature according to the one-to-one mapping relationship to obtain the ammonia reserves. The device determines the ammonia reserves through the above steps, so that the current catalyst reserves can be accurately predicted.

[0083] Specifically, since the SCR conversion efficiency is directly related to the temperature of the SCR carrier, that is, the catalyst utilization rate, the current temperature and the predicted ammonia reserves have a one-to-one mapping relationship, which can be expressed in the form of a curve or a table. Therefore, the catalyst utilization rate and the predicted ammonia reserves corresponding to the current temperature can be determined through the one-to-one mapping relationship, that is, the current ammonia reserves.

[0084] In some optional embodiments, the switching unit includes a calculation module and a first determination module, the calculation module is used to obtain the historical temperature of the selective catalytic reduction device, calculate the temperature difference between the current temperature and the historical temperature, wherein the historical temperature represents the temperature at a time before the current time corresponding to the current temperature; the first determination module is used to determine that the engine is in a high risk state of ammonia leakage when the ammonia reserve is greater than a preset ammonia threshold, the current temperature is greater than a preset temperature threshold, the temperature difference is a positive value, and the temperature difference is greater than a preset temperature difference, and switches the engine torque to the first ammonia clearing torque. The device further determines to switch the engine torque to the first ammonia clearing torque through the above steps, so that the risk of ammonia leakage can be further determined and further measures can be taken to prevent ammonia leakage for a long time.

[0085] In the specific implementation process, in order to further determine the risk of ammonia leakage, it is also necessary to determine the temperature change amplitude of the SCR carrier, that is, to determine whether it is a rapid temperature rise process. This can be determined by whether the temperature difference of the historical temperature at a certain moment before the current moment corresponding to the current temperature is greater than the preset temperature difference. The historical moment can be a moment such as 10 minutes before the current moment. If it is satisfied, it indicates that the engine is in a high risk state of ammonia leakage, and the torque of the engine is switched to the first ammonia removal torque.

[0086] In some optional embodiments, the switching unit further includes a second acquisition module and a first switching module, the second acquisition module is used to acquire the current battery power state of the power battery; the first switching module is used to switch the torque of the engine to the first ammonia-clearing torque when the current battery power state indicates that the battery power of the power battery is greater than a preset power threshold. The device switches the torque through the above steps when the current SOC (battery power state, State of Charge, SOC for short) of the power battery indicates that the battery power is sufficient, so as to ensure that the engine has sufficient power.

[0087] Specifically, in order to ensure that the engine has sufficient power, the ammonia clearing mode is triggered only when the engine is in a high risk state of ammonia leakage and the current SOC (battery power) is greater than a preset power threshold.

[0088] In some optional embodiments, after the torque of the engine is switched to the first ammonia clearing torque, the device further includes an acquisition unit and a second switching unit, the acquisition unit is used to acquire the total required torque; the second switching unit is used to calculate the difference between the total required torque and the first ammonia clearing torque to obtain the second ammonia clearing torque of the motor, and switch the torque of the motor to the second ammonia clearing torque, wherein the total required torque is greater than the first ammonia clearing torque. The device controls the torque of the motor to be converted through the above steps, so that the total torque load torque requirement can be guaranteed.

[0089] In the specific implementation process, the total demand torque is subtracted from the engine set torque in the first ammonia cleanup mode to obtain the set load of the motor in the ammonia cleanup mode, thereby controlling the motor operation. This control method can effectively monitor the risk status of post-treatment ammonia leakage, and when a high risk of ammonia leakage is detected, the exhaust temperature can be effectively reduced by controlling the engine torque, reducing the occurrence of ammonia leakage and reducing the failure rate of exceeding 1.2.

[0090] In some optional embodiments, the first determination unit includes a second determination module, which is used to calculate the difference between the first mass flow rate and the second mass flow rate to obtain the conversion mass flow rate, and determine the catalyst utilization rate according to the conversion mass flow rate.

[0091] In the specific implementation process, the first NOx mass flow rate is subtracted from the second NOx mass flow rate to obtain the conversion mass flow rate; the actual urea flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate.

[0092] In some optional embodiments, the second determination module includes a first calculation submodule and a second calculation submodule, the first calculation submodule is used to obtain a conversion coefficient, calculate the product of the conversion mass flow and the conversion coefficient, and obtain the catalyst consumption, wherein the conversion coefficient represents the conversion rate between the nitrogen oxide and the catalyst; the second calculation submodule is used to obtain the catalyst injection amount, calculate the ratio of the catalyst consumption to the catalyst injection amount, and obtain the catalyst utilization rate. The device calculates the catalyst utilization rate through the above steps, so that the catalyst utilization rate can be accurately calculated.

[0093] Specifically, the conversion relationship between NOx and urea can be determined by the conversion coefficient, so the catalyst consumption is obtained by multiplying the conversion mass flow rate and the conversion coefficient; and the catalyst utilization rate can be obtained by the ratio of the catalyst consumption to the catalyst injection amount.

[0094] The ammonia leakage processing device includes a processor and a memory, and the first determination unit, the second determination unit, the switching unit, etc. are all stored in the memory as program units, and the processor executes the program units stored in the memory to implement corresponding functions. The above modules are all located in the same processor; or, the above modules are located in different processors in any combination.

[0095] The processor includes a kernel, which calls the corresponding program unit from the memory. One or more kernels can be set to solve the ammonia leakage problem by adjusting the kernel parameters.

[0096] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0097] An embodiment of the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium includes a stored program, wherein when the program is executed, a device where the computer-readable storage medium is located is controlled to execute the ammonia leakage processing method.

[0098] Specifically, the treatment methods for ammonia leakage include:

[0099] Step S201, respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer;

[0100] Specifically, the catalyst in SCR (Selective Catalytic Reduction) is generally ammonia. The ammonia reserve in the SCR carrier can be predicted based on the catalyst utilization rate, that is, the actual utilization rate of ammonia, which is achieved in the following way: the NOx mass flow rate before the post-treatment step is subtracted from the NOx mass flow rate after the post-treatment step to obtain the NOx mass flow rate converted by the post-treatment; the actual urea consumption flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate, that is, the above-mentioned catalyst utilization rate.

[0101] Step S202, obtaining the current temperature of the selective catalytic reduction device, and determining the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature;

[0102] Specifically, the ammonia reserves can be predicted based on the catalyst utilization rate and the current temperature of the SCR. Theoretically, when the SCR carrier, i.e., the selective catalytic reducer, has no ammonia reserves, the urea utilization rate is determined by the conversion efficiency, and the SCR conversion efficiency is directly related to the temperature of the SCR carrier. The two are a relatively definite relationship curve. However, when there are ammonia reserves in the SCR carrier, the stored ammonia will also participate in the conversion of NOx, thereby increasing the urea utilization rate. Therefore, the ammonia reserves of the SCR carrier can be predicted based on the actual urea utilization rate and the SCR carrier temperature. When the temperature is constant, the higher the actual urea utilization rate, the higher the level of ammonia stored in the carrier.

[0103] Step S203, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia clearing torque to reduce ammonia leakage, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

[0104] Specifically, the ammonia leakage risk state is identified based on the predicted ammonia reserve and SCR temperature: the ammonia reserve is compared with the preset ammonia threshold. If it is greater than the preset temperature threshold, the carrier is considered to be in a high ammonia storage state; and when the SCR temperature is greater than the preset temperature threshold, the engine is considered to be in a high temperature state; when at least the above two conditions are met, the SCR carrier temperature needs to be controlled in time to reduce ammonia leakage. Specifically, the engine torque can be switched to the first ammonia clearing torque, under which the engine exhaust temperature is relatively low, so as to achieve the effect of reducing the after-treatment exhaust temperature.

[0105] An embodiment of the present invention provides a hybrid vehicle, comprising: a hybrid system, the hybrid system comprising at least an engine, an electric motor and a power battery; a controller, comprising one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing any one of the ammonia leakage processing methods described above:

[0106] Step S201, respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer;

[0107] Specifically, the catalyst in SCR (Selective Catalytic Reduction) is generally ammonia. The ammonia reserve in the SCR carrier can be predicted based on the catalyst utilization rate, that is, the actual utilization rate of ammonia, which is achieved in the following way: the NOx mass flow rate before the post-treatment step is subtracted from the NOx mass flow rate after the post-treatment step to obtain the NOx mass flow rate converted by the post-treatment; the actual urea consumption flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate, that is, the above-mentioned catalyst utilization rate.

[0108] Step S202, obtaining the current temperature of the selective catalytic reduction device, and determining the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature;

[0109] Specifically, the ammonia reserves can be predicted based on the catalyst utilization rate and the current temperature of the SCR. Theoretically, when the SCR carrier, i.e., the selective catalytic reducer, has no ammonia reserves, the urea utilization rate is determined by the conversion efficiency, and the SCR conversion efficiency is directly related to the temperature of the SCR carrier. The two are a relatively definite relationship curve. However, when there are ammonia reserves in the SCR carrier, the stored ammonia will also participate in the conversion of NOx, thereby increasing the urea utilization rate. Therefore, the ammonia reserves of the SCR carrier can be predicted based on the actual urea utilization rate and the SCR carrier temperature. When the temperature is constant, the higher the actual urea utilization rate, the higher the level of ammonia stored in the carrier.

[0110] Step S203, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia clearing torque to reduce ammonia leakage, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

[0111] Specifically, the ammonia leakage risk state is identified based on the predicted ammonia reserve and SCR temperature: the ammonia reserve is compared with the preset ammonia threshold. If it is greater than the preset temperature threshold, the carrier is considered to be in a high ammonia storage state; and when the SCR temperature is greater than the preset temperature threshold, the engine is considered to be in a high temperature state; when at least the above two conditions are met, the SCR carrier temperature needs to be controlled in time to reduce ammonia leakage. Specifically, the engine torque can be switched to the first ammonia clearing torque, under which the engine exhaust temperature is relatively low, so as to achieve the effect of reducing the after-treatment exhaust temperature.

[0112] The present application also provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of the method described in each embodiment of the present application:

[0113] Step S201, respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer;

[0114] Specifically, the catalyst in SCR (Selective Catalytic Reduction) is generally ammonia. The ammonia reserve in the SCR carrier can be predicted based on the catalyst utilization rate, that is, the actual utilization rate of ammonia, which is achieved in the following way: the NOx mass flow rate before the post-treatment step is subtracted from the NOx mass flow rate after the post-treatment step to obtain the NOx mass flow rate converted by the post-treatment; the actual urea consumption flow rate required to convert these NOx is calculated, and the actual urea consumption flow rate is divided by the actual urea injection flow rate to obtain the actual urea utilization rate, that is, the above-mentioned catalyst utilization rate.

[0115] Step S202, obtaining the current temperature of the selective catalytic reduction device, and determining the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature;

[0116] Specifically, the ammonia reserves can be predicted based on the catalyst utilization rate and the current temperature of the SCR. Theoretically, when the SCR carrier, i.e., the selective catalytic reducer, has no ammonia reserves, the urea utilization rate is determined by the conversion efficiency, and the SCR conversion efficiency is directly related to the temperature of the SCR carrier. The two are a relatively definite relationship curve. However, when there are ammonia reserves in the SCR carrier, the stored ammonia will also participate in the conversion of NOx, thereby increasing the urea utilization rate. Therefore, the ammonia reserves of the SCR carrier can be predicted based on the actual urea utilization rate and the SCR carrier temperature. When the temperature is constant, the higher the actual urea utilization rate, the higher the level of ammonia stored in the carrier.

[0117] Step S203, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia clearing torque to reduce ammonia leakage, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

[0118] Specifically, the ammonia leakage risk state is identified based on the predicted ammonia reserve and SCR temperature: the ammonia reserve is compared with the preset ammonia threshold. If it is greater than the preset temperature threshold, the carrier is considered to be in a high ammonia storage state; and when the SCR temperature is greater than the preset temperature threshold, the engine is considered to be in a high temperature state; when at least the above two conditions are met, the SCR carrier temperature needs to be controlled in time to reduce ammonia leakage. Specifically, the engine torque can be switched to the first ammonia clearing torque, under which the engine exhaust temperature is relatively low, so as to achieve the effect of reducing the after-treatment exhaust temperature.

[0119] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0120] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0121] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0122] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0123] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0124] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0125] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0126] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transitory media), such as modulated data signals and carrier waves.

[0127] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0128] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0129] 1) In the ammonia leakage treatment method of the present application, the mass flow rate of nitrogen oxides before and after the post-treatment step is obtained respectively, and the catalyst utilization rate is determined according to the mass flow rate, wherein the post-treatment represents the exhaust gas treatment of the engine, and the catalyst utilization rate represents the utilization rate of the catalyst in the selective catalytic reducer; the current temperature of the selective catalytic reducer is obtained, and the ammonia reserve in the selective catalytic reducer is determined according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, the engine torque is switched to the first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is the torque automatically distributed according to the battery power state of the power battery. Compared with the prior art, the problem of ammonia leakage of the engine during the rapid heating process cannot be solved. The present application predicts the ammonia reserve by the catalyst utilization rate, and controls the torque of the engine according to the ammonia reserve to reduce the leakage of ammonia. Therefore, the problem of the lack of ammonia leakage solution in the prior art during the rapid heating process can be solved, and the effect of reducing ammonia leakage can be achieved.

[0130] 2) In the ammonia leakage treatment device of the present application, the mass flow of nitrogen oxides before and after the post-treatment step is obtained respectively, and the catalyst utilization rate is determined according to the mass flow rate, wherein the post-treatment represents the exhaust gas treatment of the engine, and the catalyst utilization rate represents the utilization rate of the catalyst in the selective catalytic reducer; the current temperature of the selective catalytic reducer is obtained, and the ammonia reserve in the selective catalytic reducer is determined according to the catalyst utilization rate and the current temperature; at least when the ammonia reserve is greater than the preset ammonia threshold and the current temperature is greater than the preset temperature threshold, the torque of the engine is switched to the first ammonia clearing torque to reduce the leakage of ammonia, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is the torque automatically distributed according to the battery power state of the power battery. Compared with the problem that the prior art cannot solve the ammonia leakage of the engine during the rapid heating process, the present application predicts the ammonia reserve by the catalyst utilization rate, and controls the torque of the engine according to the ammonia reserve to reduce the leakage of ammonia. Therefore, the problem of the lack of ammonia leakage solution device during the rapid heating process in the prior art can be solved, and the effect of reducing ammonia leakage can be achieved.

[0131] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for treating ammonia leakage, characterized in that: Applied to a hybrid power system, the hybrid power system at least includes an engine, an electric motor and a power battery, and the ammonia leakage treatment method includes: Respectively acquiring a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determining a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer; Acquiring a current temperature of the selective catalytic reduction device, and determining an ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature; At least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, the torque of the engine is switched to a first ammonia clearing torque to reduce ammonia leakage, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

2. The method for treating ammonia leakage according to claim 1, characterized in that: Determining the ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature includes: Obtaining a one-to-one mapping relationship between the catalyst utilization rate, the current temperature, and the predicted ammonia reserves; The predicted ammonia reserves corresponding to the catalyst utilization rate and the current temperature are determined according to the one-to-one mapping relationship to obtain the ammonia reserves.

3. The method for treating ammonia leakage according to claim 1, characterized in that: At least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, switching the torque of the engine to a first ammonia clearing torque includes: Acquiring a historical temperature of the selective catalytic reduction device, and calculating a temperature difference between the current temperature and the historical temperature, wherein the historical temperature represents a temperature at a time before a current time corresponding to the current temperature; When the ammonia reserve is greater than a preset ammonia threshold, the current temperature is greater than a preset temperature threshold, the temperature difference is a positive value, and the temperature difference is greater than a preset temperature difference, the engine is determined to be in a high-risk state for ammonia leakage, and the engine torque is switched to the first ammonia clearing torque.

4. The method for treating ammonia leakage according to claim 1, characterized in that: Switching the torque of the engine to a first ammonia-clearing torque includes: Obtaining the current battery power status of the power battery; When the current battery power state indicates that the battery power of the power battery is greater than a preset power threshold, the torque of the engine is switched to the first ammonia-clearing torque.

5. The method for treating ammonia leakage according to claim 1, characterized in that: After switching the torque of the engine to the first ammonia-clearing torque, the method further includes: Get the total required torque; The difference between the total required torque and the first ammonia clearing torque is calculated to obtain a second ammonia clearing torque of the motor, and the torque of the motor is switched to the second ammonia clearing torque, wherein the total required torque is greater than the first ammonia clearing torque.

6. The method for treating ammonia leakage according to claim 1, characterized in that: Acquiring the mass flow of nitrogen oxides before and after post-treatment, and determining the catalyst utilization rate according to the first mass flow and the second mass flow, comprising: The difference between the first mass flow rate and the second mass flow rate is calculated to obtain a conversion mass flow rate, and the catalyst utilization rate is determined according to the conversion mass flow rate.

7. The method for treating ammonia leakage according to claim 6, characterized in that: Determining the catalyst utilization rate according to the conversion mass flow rate comprises: Acquiring a conversion coefficient, calculating the product of the conversion mass flow rate and the conversion coefficient, and obtaining a catalyst consumption, wherein the conversion coefficient represents a conversion rate between the nitrogen oxides and the catalyst; The catalyst injection amount is obtained, and the ratio of the catalyst consumption to the catalyst injection amount is calculated to obtain the catalyst utilization rate.

8. A device for treating ammonia leakage, characterized in that: Applied to a hybrid power system, the hybrid power system at least includes an engine, an electric motor and a power battery, and the ammonia leakage treatment device includes: a first determining unit, configured to respectively obtain a mass flow rate of nitrogen oxides before a post-treatment step and a mass flow rate of nitrogen oxides after the post-treatment step to obtain a first mass flow rate and a second mass flow rate, and determine a catalyst utilization rate according to the first mass flow rate and the second mass flow rate, wherein the post-treatment step represents an exhaust gas treatment step of the engine, and the catalyst utilization rate represents a utilization rate of a catalyst in a selective catalytic reducer; a second determining unit, configured to obtain a current temperature of the selective catalytic reduction device, and determine an ammonia reserve in the selective catalytic reduction device according to the catalyst utilization rate and the current temperature; A switching unit is used to switch the torque of the engine to a first ammonia clearing torque to reduce ammonia leakage, at least when the ammonia reserve is greater than a preset ammonia threshold and the current temperature is greater than a preset temperature threshold, wherein the exhaust temperature of the engine under the first ammonia clearing torque is lower than the exhaust temperature of the engine under the battery power distribution torque, and the battery power distribution torque is a torque automatically distributed according to the battery power status of the power battery.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium includes a stored program, wherein when the program is executed, the device where the computer-readable storage medium is located is controlled to execute the method for processing ammonia leakage according to any one of claims 1 to 7.

10. A hybrid vehicle, characterized in that: include: A hybrid power system, the hybrid power system comprising at least an engine, an electric motor and a power battery; A controller, comprising one or more processors, a memory, and one or more programs, wherein the one or more programs are stored in the memory and are configured to be executed by the one or more processors, and the one or more programs include a method for executing the ammonia leakage processing method described in any one of claims 1 to 7.

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