Engine device, pollutant emission control method and system, and storage medium

Abstract

The invention provides an engine device, a pollutant emission control method, a pollutant emission control system and a storage medium, and relates to the technical field of automobile internal combustion engines, and the device comprises an engine which is provided with a cooling liquid inlet, a cooling liquid outlet and an engine exhaust port; the fuel preheater is provided with a fuel preheater water inlet, a fuel preheater water outlet and a fuel preheater exhaust port and comprises a water pump installed on a shell of the fuel preheater, the water pump is communicated with the fuel preheater water inlet, the fuel preheater water inlet is communicated with the cooling liquid outlet, and the fuel preheater water outlet is communicated with the cooling liquid inlet; the three-way catalyst is provided with a catalyst inlet; the electromagnetic valve is mounted on a pipeline between the exhaust port of the fuel preheater and the inlet of the catalytic converter, and the exhaust port of the engine is communicated with the inlet of the catalytic converter. According to the method, the conversion efficiency and the cost of the three-way catalyst are both considered in the cold start period of the engine.

Description

Technical Field

[0001] This application relates to the field of automotive internal combustion engine technology, and more specifically, to an engine device, a pollutant emission control method for the engine device, an engine system, and a computer-readable storage medium. Background Technology

[0002] For engines equipped with three-way catalytic converters, such as methanol engines, the conversion efficiency of the three-way catalytic converter is low during engine cold starts.

[0003] To address the technical challenge of low conversion efficiency of three-way catalytic converters during engine cold starts, various strategies have been employed, including adjusting combustion parameters (such as rail pressure and injection advance angle), adding electric heating elements, introducing additional throttle valves, or using variable valve timing systems to increase exhaust gas temperature. While these solutions can improve the temperature of the three-way catalytic converter to some extent, they often suffer from drawbacks such as high cost, high energy consumption, or adverse effects on engine performance. Summary of the Invention

[0004] The main objective of this application is to provide an engine device, a method for controlling pollutant emissions from the engine device, an engine system, and a computer-readable storage medium to at least address the problem of improving the conversion efficiency and cost of the three-way catalytic converter during engine cold start.

[0005] To achieve the above objectives, according to one aspect of this application, an engine device is provided, comprising: an engine having a coolant inlet, a coolant outlet, and an engine exhaust port; a fuel preheater having a fuel preheater inlet, a fuel preheater outlet, and a fuel preheater exhaust port, including a water pump mounted on the housing of the fuel preheater, the water pump being connected to the fuel preheater inlet and the fuel preheater inlet being connected to the coolant outlet, the fuel preheater outlet being connected to the coolant inlet, the water pump being used to pump engine coolant into the fuel preheater to heat the engine coolant before discharging it from the fuel preheater outlet; a three-way catalytic converter having a catalytic converter inlet; and a solenoid valve installed on a pipeline between the fuel preheater exhaust port and the catalytic converter inlet, the engine exhaust port being connected to the catalytic converter inlet, the solenoid valve being a three-way solenoid valve, the first port of the three-way solenoid valve being connected to the fuel preheater exhaust port, the second port of the three-way solenoid valve being connected to the catalytic converter inlet, and the third port of the three-way solenoid valve being connected to the atmosphere.

[0006] Optionally, the engine unit also includes a temperature sensor installed at the catalytic converter inlet.

[0007] Optionally, the engine is a methanol engine, and the fuel preheater further includes a methanol pump, which is installed on the housing of the fuel preheater and is used to pump methanol fuel from the methanol storage container into the fuel preheater.

[0008] According to another aspect of this application, a pollutant emission control method is provided for any of the aforementioned engine devices, comprising: before the engine is in a cold start condition and not yet started, controlling the water pump of the fuel preheater to pump engine coolant into the fuel preheater to heat the engine coolant, and starting the engine when the temperature of the engine coolant reaches a first preset temperature; after the engine is started, and during the engine's low-temperature operation, controlling the solenoid valve to open so that the exhaust port of the fuel preheater is connected to the catalytic converter inlet of the three-way catalytic converter, so as to use the waste heat of the fuel preheater to heat the three-way catalytic converter.

[0009] Optionally, the method further includes: after controlling the solenoid valve to open so that the exhaust port of the fuel preheater is connected to the catalytic converter inlet of the three-way catalytic converter to heat the three-way catalytic converter using the waste heat of the fuel preheater, the method further includes: after the temperature of the engine coolant reaches a second preset temperature, controlling the fuel preheater to stop heating, wherein the second preset temperature is greater than the first preset temperature.

[0010] Optionally, the method further includes: monitoring the temperature at the catalytic converter inlet of the three-way catalytic converter to obtain the inlet temperature; and when the inlet temperature is greater than or equal to the upper temperature limit, controlling the solenoid valve to cut off the connection between the fuel preheater exhaust port and the catalytic converter inlet, and controlling the gas discharged from the fuel preheater exhaust port to be discharged into the atmosphere.

[0011] Optionally, the method further includes: acquiring the external ambient temperature; and extending the duration for which the fuel preheater heats the engine coolant when the external ambient temperature is lower than a preset low temperature.

[0012] According to another aspect of this application, an engine system is provided, comprising: any of the engine devices described herein; and an electronic control unit, communicating with the engine device, for executing any of the pollutant emission control methods described herein.

[0013] According to another aspect of this application, a computer-readable storage medium is provided, the computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform any of the pollutant emission control methods described above.

[0014] According to the technical solution of this application, the engine device includes: an engine having a coolant inlet, a coolant outlet, and an engine exhaust port; a fuel preheater having a fuel preheater inlet, a fuel preheater outlet, and a fuel preheater exhaust port, including a water pump, wherein the fuel preheater inlet is connected to the coolant outlet, and the fuel preheater outlet is connected to the coolant inlet; a three-way catalytic converter having a catalytic converter inlet; and a solenoid valve installed on a pipeline between the fuel preheater exhaust port and the catalytic converter inlet, wherein the engine exhaust port is connected to the catalytic converter inlet. In this solution, the engine coolant outlet is connected to the fuel preheater inlet, and the fuel preheater outlet is connected to the engine coolant inlet, forming a closed coolant circulation system. The fuel preheater exhaust port is connected to the catalytic converter inlet via the solenoid valve, and the engine exhaust port is also connected to the catalytic converter inlet. During the cold start phase, the solenoid valve opens, allowing the hot exhaust gas generated by the fuel preheater to preheat the three-way catalytic converter. This ensures that the three-way catalytic converter quickly enters a high-efficiency conversion state when the engine starts, eliminating the need for an additional throttle valve or a variable valve control system to increase the exhaust gas temperature. This solves the problem of balancing the conversion efficiency and cost of the three-way catalytic converter during engine cold starts. Attached Figure Description

[0015] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 A diagram of an engine device provided in an embodiment according to this application is shown;

[0017] Figure 2 A structural diagram of a fuel preheater according to an embodiment of this application is shown;

[0018] Figure 3 A flowchart is shown of a pollutant emission control method for an engine device according to an embodiment of this application;

[0019] Figure 4 A graph showing the relationship between the inlet temperature and conversion efficiency of a three-way catalytic converter according to an embodiment of this application is shown.

[0020] The above figures include the following reference numerals:

[0021] 10. Engine; 11. Coolant inlet; 12. Coolant outlet; 13. Engine exhaust port; 20. Fuel preheater; 21. Fuel preheater inlet; 22. Fuel preheater outlet; 23. Fuel preheater exhaust port; 24. Water pump; 25. Methanol pump; 30. Three-way catalytic converter; 31. Catalytic converter inlet; 40. Solenoid valve. Detailed Implementation

[0022] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] 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 with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate for the embodiments of this application described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] As described in the background section, while existing solutions can increase the temperature of the three-way catalytic converter to some extent, they often have drawbacks such as high cost, high energy consumption, or adverse effects on engine performance. To address the issue of balancing the conversion efficiency and cost of the three-way catalytic converter during engine cold starts, embodiments of this application provide an engine device, a pollutant emission control method for the engine device, an engine system, and a computer-readable storage medium.

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0027] Figure 1 and Figure 2 This is a flowchart of an engine device according to an embodiment of this application. Figure 1 and Figure 2 As shown, the device includes:

[0028] Engine 10 has a coolant inlet 11, a coolant outlet 12 and an engine exhaust port 13;

[0029] The engine 10 is responsible for converting fuel energy into mechanical energy. The coolant circulation system of the engine 10 keeps the engine 10 running at a suitable temperature to avoid overheating. At the same time, the coolant needs to be preheated during cold starts to speed up the engine 10 to reach its optimal operating state.

[0030] The fuel preheater 20 has a fuel preheater inlet 21, a fuel preheater outlet 22, and a fuel preheater exhaust port 23. It includes a water pump 24 installed on the housing of the fuel preheater 20. The water pump 24 is connected to the fuel preheater inlet 21, and the fuel preheater inlet 21 is connected to the coolant outlet 12. The fuel preheater outlet 22 is connected to the coolant inlet 11. The water pump 24 is used to pump engine coolant into the fuel preheater 20 to heat the engine coolant and then discharge it from the fuel preheater outlet 22.

[0031] Specifically, such as Figure 2 As shown, the fuel preheater 20 can be a water-fuel preheater. The fuel preheater 20 is equipped with its own water pump 24, which draws coolant from the engine 10 and guides it into the combustion chamber of the fuel preheater 20. Inside the combustion chamber, the heat generated by the combustion of methanol under the action of the ignition electrode fills the chamber with hot air. After entering the combustion chamber, the coolant exchanges heat with the hot air through convection, thereby being heated.

[0032] Before the engine 10 is cold-started, the fuel preheater 20 generates high-temperature exhaust gas by burning methanol. This exhaust gas is used not only to preheat the coolant in the fuel preheater 20 and transfer heat back to the engine 10 to accelerate the preheating process of the engine 10, but also to further preheat the three-way catalytic converter 30, so that it can reach a better state before the engine 10 is started, reducing pollutant emissions during cold start. Through the circulation of coolant, the engine 10 can be maintained at a suitable operating temperature, avoiding the adverse effects of overheating or overcooling on the performance and life of the engine 10. The engine coolant is circulated to the fuel preheater by the water pump 24 for heating, and then the heated coolant is sent back to the engine 10, which effectively improves the preheating speed of the engine 10, shortens the cold start time, and creates conditions for the rapid warm-up of the engine 10 and the emission control system.

[0033] The three-way catalytic converter 30 has a catalytic converter inlet 31;

[0034] The three-way catalytic converter 30 is used to reduce harmful gases such as carbon monoxide, unburned hydrocarbons, and nitrogen oxides emitted by the engine 10. By preheating, the three-way catalytic converter 30 can reach the optimal catalytic temperature more quickly during a cold start of the engine 10, thereby improving the efficiency of pollutant conversion.

[0035] Solenoid valve 40 is installed on the pipeline between the fuel preheater exhaust port 23 and the catalyst inlet 31, and the engine exhaust port 13 is connected to the catalyst inlet 31.

[0036] The solenoid valve 40 controls the flow direction of exhaust gas, directing it towards the three-way catalytic converter 30 for preheating or preventing exhaust gas from flowing into the three-way catalytic converter 30. The solenoid valve 40 allows, during a cold start of the engine 10, the hot exhaust gas generated by the fuel preheater 20 to be directed to the catalytic converter inlet to preheat the three-way catalytic converter 30. The waste heat generated by the fuel preheater 20 is transferred to the three-way catalytic converter 30, raising its temperature. Under normal operating temperature, the three-way catalytic converter 30 can efficiently convert harmful components in the exhaust gas into harmless substances, reducing emissions. By combining this with the exhaust gas preheating strategy of the fuel preheater 20, the temperature of the three-way catalytic converter 30 can be increased in advance during cold starts, allowing it to enter a high-efficiency conversion state more quickly and significantly reducing pollutant emissions in a cold state.

[0037] In the above embodiments, the engine unit includes: an engine having a coolant inlet, a coolant outlet, and an engine exhaust port; a fuel preheater having a fuel preheater inlet, a fuel preheater outlet, and a fuel preheater exhaust port, including a water pump, the fuel preheater inlet being connected to the coolant outlet, and the fuel preheater outlet being connected to the coolant inlet; a three-way catalytic converter having a catalytic converter inlet; and a solenoid valve installed on a pipeline between the fuel preheater exhaust port and the catalytic converter inlet, with the engine exhaust port connected to the catalytic converter inlet. In this solution, the engine coolant outlet is connected to the fuel preheater inlet, and the fuel preheater outlet is connected to the engine coolant inlet, forming a closed coolant circulation system. The fuel preheater exhaust port is connected to the catalytic converter inlet via the solenoid valve, and the engine exhaust port is also connected to the catalytic converter inlet. During the cold start phase, the solenoid valve opens, allowing the hot exhaust gas generated by the fuel preheater to preheat the three-way catalytic converter. This ensures that the three-way catalytic converter quickly enters a high-efficiency conversion state when the engine starts, eliminating the need for an additional throttle valve or a variable valve control system to increase the exhaust gas temperature. This solves the problem of balancing the conversion efficiency and cost of the three-way catalytic converter during engine cold starts.

[0038] In one alternative embodiment, the solenoid valve is a three-way solenoid valve, with the first port of the three-way solenoid valve connected to the exhaust port of the fuel preheater, the second port of the three-way solenoid valve connected to the inlet of the catalyst, and the third port of the three-way solenoid valve connected to the atmosphere.

[0039] In the above embodiments, a three-way solenoid valve is used, with its first port connected to the fuel preheater exhaust port, its second port connected to the three-way catalytic converter inlet, and its third port connected to the atmosphere. This allows the high-temperature exhaust gas generated by the fuel preheater to flexibly switch between the three-way catalytic converter heating path and the external emission path. This structure effectively improves the heating rate of the three-way catalytic converter during the cold start phase, enhances its early conversion capability, and allows the exhaust gas to bypass to the atmosphere when the temperature reaches its upper limit, preventing the catalytic converter from overheating, thus balancing emission control and system safety.

[0040] In another alternative, the engine unit also includes a temperature sensor installed at the inlet of the catalyst.

[0041] In the above embodiments, by installing a temperature sensor at the inlet of the three-way catalytic converter, the temperature information of the exhaust gas entering the catalytic converter can be obtained in real time. This allows for dynamic determination of whether the three-way catalytic converter is within its high-efficiency conversion temperature range based on the temperature data, thus precisely controlling the on / off state of the three-way solenoid valve. Installing a temperature sensor not only improves the catalytic converter's heating efficiency during cold starts and shortens the catalyst activation time, but also effectively prevents catalytic converter performance degradation due to overheating, thereby improving the engine's emission control capabilities under low-temperature conditions.

[0042] In another alternative, such as Figure 2 As shown, the engine is a methanol engine, and the fuel preheater also includes a methanol pump 25, which is installed on the housing of the fuel preheater and is used to pump methanol fuel from the methanol storage container into the fuel preheater.

[0043] The fuel preheater may include two methanol pumps 25, one for fuel delivery and the other for combustion control. One methanol pump 25 is installed on the outside of the fuel preheater housing, near the fuel preheater outlet, to deliver methanol fuel from the methanol storage container to the fuel preheater. The other methanol pump 25 is located in the fuel supply circuit of the fuel preheater to regulate the flow and pressure of methanol fuel during the ignition and steady-fire stages, ensuring the stability of the combustion process and the controllability of thermal power output. This dual-methanol pump structure enables rapid fuel supply and precise combustion control during cold starts, improving the response speed and combustion efficiency of the fuel preheater, thereby further improving the warming effect of the engine and the three-way catalytic converter.

[0044] In the above embodiments, the engine is a methanol engine, and the fuel preheater includes a methanol pump. The methanol pump delivers methanol fuel from the fuel storage container to the combustion chamber of the fuel preheater. Under the action of the ignition electrode, the methanol fuel burns to generate heat, thereby heating the coolant flowing inside the fuel preheater and causing the coolant temperature to rise rapidly. By setting up the methanol pump, a quantitative supply and stable delivery of methanol fuel is achieved, ensuring stable combustion and sufficient heat generation in the fuel preheater before engine cold start, used to heat the engine coolant and the inlet of the three-way catalytic converter. The methanol pump improves the combustion efficiency of the fuel preheater system. In addition, it gives the entire preheating system good start-up response and adaptive fuel control capabilities, further enhancing the starting performance and emission control effect of the methanol engine in low-temperature environments.

[0045] Specifically, in the application scenario where the engine is a methanol engine, the fuel preheater can also be a methanol fuel preheater, that is, a methanol pump is added to the fuel preheater to deliver methanol into the fuel preheater.

[0046] This embodiment also provides a pollutant emission control method applied to the above-mentioned engine device, such as... Figure 3 As shown, it includes:

[0047] Step S101: Before the engine is in a cold start condition and is started, control the water pump of the fuel preheater to pump the engine coolant into the fuel preheater to heat the engine coolant, and start the engine when the temperature of the engine coolant reaches the first preset temperature.

[0048] Step S102: After starting the engine, and during the engine's low-temperature operation, control the solenoid valve to open so that the exhaust port of the fuel preheater is connected to the catalytic converter inlet of the three-way catalytic converter, so as to use the waste heat of the fuel preheater to heat the three-way catalytic converter.

[0049] Specifically, the system first detects that the engine is in a cold, unstarted state, such as when the ambient temperature is low or the coolant temperature is below the set starting temperature. At this point, the fuel preheater is activated, including: the ignition device starting to ignite methanol; and the water pump starting to draw coolant from the engine's water jacket. The water pump sends the coolant from the engine to the fuel preheater for heating, and after heat exchange, it flows back to the engine's water circuit, forming a closed-loop heating circuit that gradually warms the engine. After starting the engine, the coolant temperature is monitored in real time by a temperature sensor. When the coolant temperature reaches the first preset temperature, the system determines that the engine is ready to start and executes the engine ignition start operation.

[0050] Next, when the engine is first started, the exhaust temperature is still low, and the three-way catalytic converter has not yet reached its efficient operating temperature; this is a cold emission condition. The control system opens the three-way solenoid valve, connecting the fuel preheater exhaust port to the three-way catalytic converter inlet and closing the inlet to the atmosphere. At this time, the fuel preheater continues to burn and produce high-temperature exhaust gas, which is between 300 and 350°C. This exhaust gas is introduced into the three-way catalytic converter inlet through the three-way solenoid valve. After the high-temperature exhaust gas flows in, it rapidly increases the inlet temperature of the three-way catalytic converter, accelerating the time it takes for the catalyst surface reaction temperature to reach its maximum, allowing it to enter the efficient catalytic zone as quickly as possible. The temperature in the efficient catalytic zone is greater than or equal to 450°C.

[0051] The first preset temperature is the lower limit of the coolant temperature at which the engine can be started. Through engine cold start test and coolant temperature rise curve test, a safe temperature point with a start success rate of more than 95% after the coolant temperature is reached is selected as the first preset temperature.

[0052] In the above embodiments, by controlling the fuel preheater water pump to circulate and heat the engine coolant before engine cold start, the engine has good temperature rise conditions before starting, thereby improving the starting reliability and success rate of the engine in low-temperature environments, reducing incomplete combustion during the starting process, and lowering initial emissions. After the engine starts, the high-temperature exhaust gas generated by the fuel preheater is introduced into the inlet of the three-way catalytic converter by controlling the solenoid valve, directly heating the three-way catalytic converter, effectively raising its temperature, allowing it to reach the activation temperature zone as soon as possible, shortening the ignition time of the catalytic converter, improving the pollutant conversion efficiency in the cold stage, and reducing exhaust emissions. This solution makes full use of the waste heat resources generated during the combustion process of the fuel preheater, without the need to introduce an additional throttle valve or use a variable valve control system to increase the exhaust gas temperature, solving the problem of improving the conversion efficiency of the three-way catalytic converter and reducing costs during engine cold start.

[0053] like Figure 4 As shown, under cold-state cycling, the inlet temperature of the three-way catalytic converter is low, making it difficult for the catalyst to ignite, significantly reducing conversion efficiency, and significantly increasing the risk of emissions exceeding limits. Therefore, increasing the inlet temperature of the three-way catalytic converter plays a decisive role in reducing the emissions of spark-ignition methanol engines. By utilizing the waste heat generated by the methanol fuel preheater during the initial start-up of the methanol engine, the three-way catalytic converter can be preheated, bringing its inlet temperature to the level of highest conversion efficiency. When the methanol fuel preheater stops heating and the methanol engine starts cold, the three-way catalytic converter is already operating in its high-efficiency conversion range, thus controlling pollutant emissions from the methanol engine under cold-state operating conditions.

[0054] In some exemplary embodiments, after controlling the solenoid valve to open so that the exhaust port of the fuel preheater is connected to the catalytic converter inlet of the three-way catalytic converter to heat the three-way catalytic converter using the waste heat of the fuel preheater, the method further includes: after the temperature of the engine coolant reaches a second preset temperature, controlling the fuel preheater to stop heating, wherein the second preset temperature is greater than the first preset temperature.

[0055] Specifically, when the engine is running at low temperatures, the three-way catalytic converter has not yet reached its operating temperature. The controller controls the three-way solenoid valve to open, connecting the exhaust port of the fuel preheater to the inlet of the three-way catalytic converter. The exhaust gas generated by the continuous combustion in the fuel preheater is introduced into the catalytic converter inlet, directly heating the three-way catalytic converter and accelerating its temperature rise to the catalytic activation temperature. During the continuous operation of the fuel preheater, the engine body temperature continuously rises due to the continuous heating of the coolant. When the coolant temperature is detected to rise to the second preset temperature, the controller determines that the engine has fully entered a stable operating condition, at which point the fuel preheater combustion system is shut down, and heating is stopped.

[0056] The aforementioned second preset temperature is the upper limit of the coolant temperature before the fuel preheater stops heating. By monitoring the coolant temperature at the second preset temperature, it is possible to indirectly determine whether the catalyst preheating is complete, thus avoiding energy waste or component overheating caused by continued heating. By combining exhaust temperature and coolant temperature sampling data, the upper limit temperature point that can stably maintain the catalyst activation temperature range and prevent the cooling system from overheating is selected as the second preset temperature.

[0057] In the above embodiments, the coolant temperature reaching the second preset temperature indicates that the engine has transitioned from a cold start to a relatively stable operating phase. Using the second preset temperature as a stopping condition can save methanol fuel consumption and improve thermal efficiency while ensuring the catalytic converter preheating effect. Furthermore, continuous heating of the coolant may cause the catalytic converter to overheat. Setting the second preset temperature to control the fuel preheater to stop heating helps indirectly control the catalytic converter's temperature rise process, protecting its operating temperature range and preventing high-temperature aging. Simultaneously, the second preset temperature serves as a basis for judging changes in the engine's thermal state, eliminating the need for additional manual intervention during the heating process and enhancing the intelligence of the vehicle's low-temperature emission control system.

[0058] In other exemplary embodiments, the method further includes: monitoring the temperature at the catalytic converter inlet of the three-way catalytic converter to obtain the inlet temperature; when the inlet temperature is greater than or equal to the upper temperature limit, controlling the solenoid valve to cut off the connection between the fuel preheater exhaust port and the catalytic converter inlet, and controlling the gas discharged from the fuel preheater exhaust port to be discharged into the atmosphere.

[0059] Specifically, the upper limit of the inlet temperature is the upper limit of the safe operating temperature allowed for the three-way catalytic converter. This is used to prevent the catalytic converter from being exposed to a high-temperature environment for a long time, which could cause sintering of the catalytic layer, decreased activity, or structural damage. By monitoring the exhaust gas temperature at the catalytic converter inlet, when the inlet temperature is greater than or equal to the upper limit of the temperature, the solenoid valve switches from the original state of being connected between the fuel preheater exhaust port and the three-way catalytic converter inlet to being connected between the fuel preheater exhaust port and the atmospheric passage. Thus, the hot exhaust gas generated by the continued operation of the fuel preheater no longer flows to the three-way catalytic converter.

[0060] In the above embodiments, since the three-way catalytic converter is highly sensitive to temperature, prolonged exposure to overheating conditions may lead to sintering of the catalytic material, damage to the support structure, or failure of the active components. This control strategy can interrupt the heating path when the temperature exceeds the limit, inhibiting the continuous rise in temperature, avoiding thermal damage, and extending the service life of the catalytic converter. Compared to determining whether to terminate heating based solely on time or coolant temperature, this solution uses the catalytic converter inlet temperature as a direct control quantity, resulting in more precise control and a faster response speed. Furthermore, once the catalytic converter has reached the target temperature, continuing to introduce exhaust gas from the fuel preheater will no longer generate conversion benefits and may even lead to energy waste. Timely cutting off the heating path through temperature limiting control saves methanol fuel consumption. The switching action of the solenoid valve guides the exhaust gas from the fuel preheater to the atmosphere in overheating conditions, unloading the heat load without interrupting the operation of the fuel preheater, avoiding local risks to the exhaust system due to high pressure or high temperature, and improving the overall stability of the system.

[0061] In one alternative, the method further includes: acquiring the external ambient temperature; and extending the duration for which the fuel preheater heats the engine coolant when the external ambient temperature is lower than a preset low temperature.

[0062] In the above embodiments, when the ambient temperature is low, the initial temperature of the engine coolant is even lower and heat loss is faster. If the heating time is controlled according to the conventional method, the coolant temperature rise may be insufficient, making it difficult to start the engine. Extending the fuel preheater heating time can make the thermal state of the engine and cooling system more stable, which helps to increase the initial temperature of the catalyst inlet, accelerate the ignition process of the catalyst, and improve cold emissions. Compared with a fixed heating time or a fixed temperature target, this solution dynamically adjusts the control strategy according to the ambient temperature, which has the advantages of strong climate adaptability and high control precision, and improves the overall intelligence level of the system.

[0063] Specifically, by acquiring the current ambient temperature, it is determined whether the current ambient temperature is lower than a preset low temperature. If the current ambient temperature is lower than the preset value, the operating time of the fuel preheater is appropriately extended. This includes extending the ignition heating duration of the fuel preheater or extending the water pump circulation time, to address the issue of faster coolant heat dissipation at lower ambient temperatures. When the coolant temperature reaches the adjusted first preset temperature, the engine is started.

[0064] The aforementioned preset low temperature characterizes an environment with extremely low temperatures.

[0065] This application also provides a specific embodiment of switching the solenoid valve path by monitoring the catalytic converter inlet temperature. A high-temperature exhaust temperature sensor is installed at the inlet of the three-way catalytic converter in the engine unit to collect the real-time catalytic converter inlet temperature and set a set upper temperature limit, such as 500°C, as the safe operating temperature threshold for the catalytic converter. When the engine is in the low-temperature operation phase after a cold start, the three-way solenoid valve is controlled to connect the fuel preheater exhaust port and the catalytic converter inlet, so as to quickly preheat the three-way catalytic converter using the high-temperature exhaust gas generated by the fuel preheater. As preheating proceeds, the exhaust temperature sensor continuously uploads catalytic converter inlet temperature data; when the inlet temperature is detected to reach or exceed 500°C, the following control actions are immediately executed: the three-way solenoid valve is controlled to switch the path, so that the connection between the fuel preheater exhaust port and the catalytic converter inlet is closed; simultaneously, the fuel preheater exhaust is guided to the third port of the solenoid valve and directly discharged into the atmosphere. This scheme achieves temperature limit control during the catalytic converter temperature rise process, avoids high-temperature failure caused by continuous waste heat input, protects the active coating and structure of the catalytic converter, and extends the service life of the system.

[0066] This application also provides an engine system, including: the engine device described above; and an electronic control unit, communicating with the engine device, for executing the pollutant emission control method described above.

[0067] Specifically, when the engine is detected to be in a cold, unstarted state, the electronic control unit (ECU) controls the fuel preheater to start, initiating methanol ignition and combustion; simultaneously, it controls the water pump to draw engine coolant into the fuel preheater for heating; the heated coolant circulates back, continuously raising the engine water temperature. When the coolant temperature reaches the first preset temperature, the control system allows the engine to start; after successful engine start, it enters a low-temperature operation phase. In the initial stage of engine operation, the exhaust gas temperature is still low, and the three-way catalytic converter has not yet reached its ignition temperature; at this time, the ECU controls the three-way solenoid valve to open, guiding the exhaust gas generated by the methanol fuel preheater into the catalytic converter inlet; the exhaust gas preheats the three-way catalytic converter, raising its temperature and shortening its activation time. The ECU simultaneously performs the following two monitoring functions: 1. Continuously monitors the coolant temperature; when the temperature reaches the second preset temperature, it determines that the engine has entered a thermal steady state, controls the fuel preheater to stop heating, and terminates the auxiliary heating process for the coolant and catalytic converter. 2. Monitor the inlet temperature of the three-way catalytic converter in real time. If the temperature reaches or exceeds the upper limit, control the solenoid valve to switch the path so that the exhaust gas from the fuel preheater is no longer introduced into the catalytic converter, but is introduced into the atmosphere to prevent the catalytic converter from overheating and being damaged.

[0068] Through the coordinated operation of the electronic control unit and the engine, the coolant temperature and catalytic converter temperature can be dynamically monitored at each stage of engine cold start. Based on the detection results, the working status of the fuel preheater, water pump and three-way solenoid valve can be precisely controlled, which effectively improves the pollutant control capability and response efficiency. There is no need to introduce an additional throttle valve or use a variable valve control system to increase the exhaust gas temperature, thus balancing the conversion efficiency and cost of the three-way catalytic converter.

[0069] This invention provides a computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the pollutant emission control method of the engine device.

[0070] Specifically, the methods for controlling pollutant emissions from engine devices include:

[0071] Step S101: Before the engine is in a cold start condition and is started, the water pump of the fuel preheater is controlled to pump the engine coolant into the fuel preheater to heat the engine coolant, and the engine is started when the temperature of the engine coolant reaches the first preset temperature.

[0072] Step S102: After starting the engine, and during the engine's low-temperature operation, control the solenoid valve to open so that the exhaust port of the fuel preheater is connected to the catalytic converter inlet of the three-way catalytic converter, so as to use the waste heat of the fuel preheater to heat the three-way catalytic converter.

[0073] Specifically, the system first detects that the engine is in a cold, unstarted state, such as when the ambient temperature is low or the coolant temperature is below the set starting temperature. At this point, the fuel preheater is activated, including: the ignition device starting to ignite methanol; and the water pump starting to draw coolant from the engine's water jacket. The water pump sends the coolant from the engine to the fuel preheater for heating, and after heat exchange, it flows back to the engine's water circuit, forming a closed-loop heating circuit that gradually warms the engine. After starting the engine, the coolant temperature is monitored in real time by a temperature sensor. When the coolant temperature reaches the first preset temperature, the system determines that the engine is ready to start and executes the engine ignition start operation.

[0074] Next, when the engine is first started, the exhaust temperature is still low, and the three-way catalytic converter has not yet reached its efficient operating temperature; this is a cold emission condition. The control system opens the three-way solenoid valve, connecting the fuel preheater exhaust port to the three-way catalytic converter inlet and closing the inlet to the atmosphere. At this time, the fuel preheater continues to burn and produce high-temperature exhaust gas, which is between 300 and 350°C. This exhaust gas is introduced into the three-way catalytic converter inlet through the three-way solenoid valve. After the high-temperature exhaust gas flows in, it rapidly increases the inlet temperature of the three-way catalytic converter, accelerating the time it takes for the catalyst surface reaction temperature to reach its maximum, allowing it to enter the efficient catalytic zone as quickly as possible. The temperature in the efficient catalytic zone is greater than or equal to 450°C.

[0075] The first preset temperature is the lower limit of the coolant temperature at which the engine can be started. Through engine cold start test and coolant temperature rise curve test, a safe temperature point with a start success rate of more than 95% after the coolant temperature is reached is selected as the first preset temperature.

[0076] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. They can be implemented using computer-executable program code, and thus can be stored in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0077] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0078] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0079] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0080] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0081] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0082] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0083] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, 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 technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0084] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0085] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0086] As can be seen from the above description, the embodiments of this application achieve the following technical effects:

[0087] According to the technical solution of this application, the engine device includes: an engine having a coolant inlet, a coolant outlet, and an engine exhaust port; a fuel preheater having a fuel preheater inlet, a fuel preheater outlet, and a fuel preheater exhaust port, including a water pump, wherein the fuel preheater inlet is connected to the coolant outlet, and the fuel preheater outlet is connected to the coolant inlet; a three-way catalytic converter having a catalytic converter inlet; and a solenoid valve installed on a pipeline between the fuel preheater exhaust port and the catalytic converter inlet, wherein the engine exhaust port is connected to the catalytic converter inlet. In this solution, the engine coolant outlet is connected to the fuel preheater inlet, and the fuel preheater outlet is connected to the engine coolant inlet, forming a closed coolant circulation system. The fuel preheater exhaust port is connected to the catalytic converter inlet via the solenoid valve, and the engine exhaust port is also connected to the catalytic converter inlet. During the cold start phase, the solenoid valve opens, allowing the hot exhaust gas generated by the fuel preheater to preheat the three-way catalytic converter. This ensures that the three-way catalytic converter quickly enters a high-efficiency conversion state when the engine starts, eliminating the need for an additional throttle valve or a variable valve control system to increase the exhaust gas temperature. This solves the problem of balancing the conversion efficiency and cost of the three-way catalytic converter during engine cold starts.

[0088] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An engine device, characterized in that, include: The engine (10) has a coolant inlet (11), a coolant outlet (12) and an engine exhaust port (13). The fuel preheater (20) has a fuel preheater inlet (21), a fuel preheater outlet (22) and a fuel preheater exhaust port (23), and includes a water pump (24) installed on the housing of the fuel preheater (20). The water pump (24) is connected to the fuel preheater inlet (21), and the fuel preheater inlet (21) is connected to the coolant outlet (12). The fuel preheater outlet (22) is connected to the coolant inlet (11). The water pump (24) is used to pump engine coolant into the fuel preheater (20) to heat the engine coolant and then discharge it from the fuel preheater outlet (22). Three-way catalytic converter (30), having a catalytic converter inlet (31); A solenoid valve (40) is installed on the pipeline between the fuel preheater exhaust port (23) and the catalyst inlet (31), and the engine exhaust port (13) is connected to the catalyst inlet (31); the solenoid valve (40) is a three-way solenoid valve, the first port of the three-way solenoid valve is connected to the fuel preheater exhaust port (23), the second port of the three-way solenoid valve is connected to the catalyst inlet (31), and the third port of the three-way solenoid valve is connected to the atmosphere.

2. The engine device according to claim 1, characterized in that, The engine unit also includes a temperature sensor installed at the catalyst inlet (31).

3. The engine device according to claim 1, characterized in that, The engine (10) is a methanol engine, and the fuel preheater (20) also includes a methanol pump (25), which is installed on the housing of the fuel preheater (20) and is used to pump methanol fuel from the methanol storage container into the fuel preheater (20).

4. A pollutant emission control method, wherein the pollutant emission control method is applied to the engine device according to any one of claims 1 to 3, characterized in that, include: Before the engine (10) is in a cold start condition and is not started, the water pump (24) of the fuel preheater (20) is controlled to pump the engine coolant into the fuel preheater (20) to heat the engine coolant, and the engine (10) is started when the temperature of the engine coolant reaches the first preset temperature. After the engine (10) is started, and during the low-temperature operation of the engine (10), the solenoid valve (40) is controlled to open so that the exhaust port (23) of the fuel preheater is connected to the catalyst inlet (31) of the three-way catalytic converter (30) so as to use the waste heat of the fuel preheater (20) to heat the three-way catalytic converter (30).

5. The pollutant emission control method according to claim 4, characterized in that, include: After controlling the solenoid valve (40) to open so that the fuel preheater exhaust port (23) is connected to the catalytic converter inlet (31) of the three-way catalytic converter (30) to heat the three-way catalytic converter (30) using the waste heat of the fuel preheater (20), the method further includes: After the engine coolant temperature reaches the second preset temperature, the fuel preheater (20) is controlled to stop heating, wherein the second preset temperature is greater than the first preset temperature.

6. The pollutant emission control method according to claim 4, characterized in that, The method further includes: The inlet temperature is obtained by monitoring the temperature at the catalyst inlet (31) of the three-way catalytic converter (30); When the inlet temperature is greater than or equal to the upper temperature limit, the solenoid valve (40) is controlled to operate to cut off the connection between the fuel preheater exhaust port (23) and the catalyst inlet (31), and the gas discharged from the fuel preheater exhaust port (23) is controlled to be discharged to the atmosphere.

7. The pollutant emission control method according to claim 4, characterized in that, The method further includes: Obtain the external ambient temperature; When the external ambient temperature is lower than the preset low temperature, the duration for which the fuel preheater (20) heats the engine coolant is extended.

8. An engine system, characterized in that, include: The engine device according to any one of claims 1 to 3; An electronic control unit, communicating with the engine unit, is used to execute the pollutant emission control method according to any one of claims 4 to 7.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the pollutant emission control method according to any one of claims 4 to 7.

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