Engine exhaust temperature control system, exhaust temperature control method, and vehicle

Abstract

The present invention discloses an exhaust temperature control system, exhaust temperature control method, and vehicle for an engine. The exhaust temperature control system operates in a first mode when first temperature information is greater than or equal to a first preset temperature, wherein the cylinder deactivation mechanism and VGT supercharger are activated, the EGR valve is deactivated, and the fuel injection mechanism's pre-injection and main fuel injection functions are activated, while the post-injection function is deactivated. Furthermore, when the first temperature information is less than the first preset temperature, second temperature information of a second SCR is obtained, and when the second temperature information is less than a second preset temperature, the engine is operated in a second mode, wherein the cylinder deactivation mechanism is deactivated, the VGT supercharger and EGR valve are activated, and the fuel injection mechanism's pre-injection, main fuel injection, and post-injection functions are all activated. In this manner, in the first mode, engine fuel consumption can be improved, and in the second mode, rapid temperature rise can be achieved, reducing the generation of harmful emissions.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of engine technology, and more particularly to an engine exhaust temperature control system, an exhaust temperature control method, and a vehicle. Background Art

[0002] As public awareness of environmental protection grows, vehicle emissions regulations are becoming increasingly stringent. The European Union officially adopted the Euro VII emission standard and the heavy-duty vehicle CO2 emission standard in 2024. my country has phased in the implementation of the National VI emission standard nationwide, and the National VII emission standard has entered the pre-research stage. Commercial vehicles will face even stricter emissions and fuel consumption regulations in the future.

[0003] Nitrogen oxides (NOx) are a major emission from diesel engines. EGR (Exhaust Gas Recirculation) and SCR (Selective Catalytic Reduction) are the primary technologies used to control NOx emissions. To meet future regulatory requirements, China VI diesel engines require technological upgrades to more precisely control NOx emissions and reduce fuel consumption. Furthermore, more efficient exhaust gas thermal management technologies are needed to maintain the post-processor's high-efficiency operating range and improve conversion efficiency. Summary of the Invention

[0004] The present invention provides an exhaust temperature control system, an exhaust temperature control method, and a vehicle for an engine. When first temperature information of a first SCR is greater than or equal to a first preset temperature, the engine is controlled to operate in a first operating mode to improve fuel consumption during normal operation of the engine. When the first temperature information of the first SCR is less than the first preset temperature, second temperature information of a second SCR is obtained. When the second temperature information is less than the second preset temperature, the engine is controlled to operate in a second mode to quickly heat a post-processing device to a normal operating temperature to reduce the generation of harmful emissions.

[0005] In a first aspect, an embodiment of the present invention provides an exhaust temperature control system for an engine, the engine comprising an engine body, a cylinder deactivation mechanism, a fuel injection mechanism, an EGR valve, and a VGT supercharger; the exhaust temperature control system comprising a monitoring control module and a post-processing device;

[0006] The aftertreatment device includes a first SCR far from the VGT supercharger and a second SCR close to the VGT supercharger;

[0007] The monitoring and control module is electrically connected to the engine and the after-treatment device, respectively, and is configured to obtain first temperature information of the first SCR and, when the first temperature information is greater than or equal to a first preset temperature, send a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger, so as to operate the engine in a first mode. In the first mode, the cylinder deactivation mechanism and the VGT supercharger are in an operating state, the EGR valve is deactivated, and a fuel pre-injection function and a fuel main injection function of the fuel injection mechanism are activated, and a fuel post-injection function is deactivated.

[0008] The monitoring and control module is further configured to obtain second temperature information of the second SCR when the first temperature information is less than the first preset temperature, and to initiate a second control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger when the second temperature information is less than the second preset temperature, so as to enable the engine to operate in a second mode. In the second mode, the cylinder deactivation mechanism stops working, the VGT supercharger and the EGR valve are in working state, and the fuel pre-injection function, the fuel main injection function, and the fuel post-injection function of the fuel injection mechanism are all enabled; and the first preset temperature is greater than the second preset temperature.

[0009] Optionally, the monitoring and control module is also used to obtain the oil temperature information of the engine body when the second temperature information is greater than or equal to the second preset temperature, and to control the engine to operate in the second mode when the oil temperature information is less than a third preset temperature, and to send a third control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger when the oil temperature information is greater than or equal to the third preset temperature, so that the engine operates in the third mode. In the third mode, the cylinder deactivation mechanism, the VGT and the EGR valve are all in working condition, and the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism are started, and the fuel post-injection function is disabled, wherein the third preset temperature is lower than the second preset temperature.

[0010] Optionally, in the first mode, the cylinder deactivation mechanism determines first cylinder deactivation information according to the speed and load of the engine body and operates according to the first cylinder deactivation information, wherein the first cylinder deactivation information includes a first cylinder deactivation area, a first cylinder deactivation number, and a first cylinder deactivation combination;

[0011] In the third mode, the cylinder deactivation mechanism determines second cylinder deactivation information according to the speed and load of the engine body and operates according to the second cylinder deactivation information, where the second cylinder deactivation information includes a second cylinder deactivation area, a second cylinder deactivation number, and a second cylinder deactivation combination.

[0012] Optionally, the second cylinder deactivation area is larger than the first cylinder deactivation area.

[0013] Optionally, when the VGT supercharger is in an operating state, the opening information of the VGT supercharger is determined according to the speed and load of the engine body;

[0014] The opening information of the VGT supercharger in the second mode is greater than the opening information of the VGT supercharger in the third mode, and the opening information of the VGT supercharger in the third mode is greater than the opening information of the VGT supercharger in the first mode.

[0015] Optionally, when the EGR valve is in a working state, the opening information of the EGR valve is determined according to the speed and load of the engine body;

[0016] The opening degree information of the EGR valve in the second mode is greater than the opening degree information of the EGR valve in the third mode.

[0017] Optionally, the volume of the first SCR is T1, the volume of the second SCR is T2, and the relationship between the first SCR and the second SCR is: 1 / 4≤T2 / T1≤1 / 2.

[0018] Optionally, the monitoring and control module includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor and an oil temperature sensor;

[0019] The first temperature sensor is disposed at the air outlet of the first SCR, and the second temperature sensor is disposed at the air inlet of the first SCR;

[0020] The third temperature sensor is provided at the air outlet of the second SCR, and the fourth temperature sensor is provided at the air inlet of the second SCR;

[0021] The monitoring and control module is further configured to determine the first temperature information based on the temperature information of the first temperature sensor and the temperature information of the second temperature sensor, and to determine the second temperature information based on the temperature information of the third temperature sensor and the temperature information of the fourth temperature sensor;

[0022] The oil temperature sensor is arranged on the engine body.

[0023] In a second aspect, an embodiment of the present invention further provides an engine exhaust temperature control method, which is applied to the engine exhaust temperature control system according to any one of the first aspects. The exhaust temperature control method includes:

[0024] obtaining first temperature information of the first SCR;

[0025] and, when the first temperature information is greater than or equal to a first preset temperature, sending a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger to operate the engine in a first mode. In the first mode, the cylinder deactivation mechanism and the VGT supercharger are in an operating state, the EGR valve is deactivated, and the fuel pilot injection function and the fuel main injection function of the fuel injection mechanism are activated, while the fuel post-injection function is deactivated.

[0026] When the first temperature information is less than the first preset temperature, second temperature information of the second SCR is obtained, and when the second temperature information is less than the second preset temperature, a second control signal is sent to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger to make the engine operate in a second mode. In the second mode, the cylinder deactivation mechanism stops working, the VGT supercharger and the EGR valve are in working state, and the fuel pre-injection function, the fuel main injection function and the fuel post-injection function of the fuel injection mechanism are all enabled; the first preset temperature is greater than the second preset temperature.

[0027] An embodiment of the present invention provides an exhaust gas temperature control system for an engine. The engine includes an engine body, a cylinder deactivation mechanism, a fuel injection mechanism, an EGR valve, and a VGT supercharger. The exhaust gas temperature control system includes a monitoring and control module and a post-processing device. The post-processing device includes a first SCR located remote from the VGT supercharger and a second SCR located near the VGT supercharger. The monitoring and control module is electrically connected to the engine and the post-processing device, respectively, and is configured to obtain first temperature information from the first SCR. When the first temperature information is greater than or equal to a first preset temperature, the monitoring and control module sends a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger to operate the engine in a first mode. Thus, when the first temperature information is detected to be greater than or equal to the first preset temperature, i.e., when the post-processing device is at a normal operating temperature, the engine's fuel consumption is improved by switching to the first mode, i.e., controlling the cylinder deactivation mechanism and the VGT supercharger to operate, deactivating the EGR valve, activating the pre-injection and main injection functions of the fuel injection mechanism, and deactivating the post-injection function. The monitoring and control module is also used to obtain second temperature information of the second SCR when the first temperature information is less than the first preset temperature, and to initiate a second control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger when the second temperature information is less than the second preset temperature, so that the engine operates in the second mode. In this way, when it is detected that the first temperature information is less than the first preset temperature and the second temperature information is less than the second preset temperature, that is, when the after-treatment device does not reach the expected temperature, by switching to the second mode, that is, controlling the cylinder deactivation mechanism to stop working, the VGT supercharger and the EGR valve to be in a working state, and the fuel pre-injection function, the fuel main injection function and the fuel post-injection function of the fuel injection mechanism are all enabled, so as to quickly heat up the after-treatment device to a normal operating temperature, improve the conversion efficiency of the after-treatment device, and reduce the generation of harmful emissions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 1 is a schematic structural diagram of an engine exhaust temperature control system provided by an embodiment of the present invention;

[0029] Figure 2 It is a flow chart of an engine exhaust temperature control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0030] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be fully described below in conjunction with the accompanying drawings of the embodiments of the present invention through specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0031] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes 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.

[0032] Figure 1 This is a schematic diagram of the structure of an engine exhaust temperature control system provided by an embodiment of the present invention. Figure 1 The engine 10 includes an engine body 110, a cylinder deactivation mechanism 120, a fuel injection mechanism 130, an EGR valve 140, and a VGT supercharger 150. The exhaust temperature control system 20 includes a monitoring and control module 210 and an after-treatment device 220. The after-treatment device 220 includes a first SCR located remote from the VGT supercharger 150 and a second SCR located near the VGT supercharger 150. The monitoring and control module 210 is electrically connected to the engine 10 and the after-treatment device 220 and is configured to obtain first temperature information of the first SCR. When the first temperature information is greater than or equal to a first preset temperature, the monitoring and control module 210 sends a first control signal to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140, and the VGT supercharger 150 to operate the engine 10 in a first mode. In the first mode, the cylinder deactivation mechanism 120 and the VGT supercharger 150 are in an active state, the EGR valve 140 is deactivated, and the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism 130 are activated, while the fuel post-injection function is deactivated. The monitoring and control module 210 is further configured to obtain second temperature information of the second SCR when the first temperature information is less than a first preset temperature, and to send a second control signal to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140, and the VGT supercharger 150 when the second temperature information is less than a second preset temperature, so as to operate the engine 10 in a second mode. In the second mode, the cylinder deactivation mechanism 120 is deactivated, the VGT supercharger 150 and the EGR valve 140 are in an operative state, and the pilot fuel injection function, the main fuel injection function, and the post fuel injection function of the fuel injection mechanism 130 are all enabled. The first preset temperature is greater than the second preset temperature.

[0033] Specifically, the engine body 110 includes a plurality of cylinders, and the plurality of cylinders are connected to the cylinder deactivation mechanism 120. When the cylinder deactivation mechanism 120 is in operation, the intake valve and exhaust valve of one or more cylinders can be controlled to stop working and be in a closed state according to the control signal of the monitoring control module 210, thereby entering the cylinder deactivation mode. When the cylinder deactivation mechanism 120 stops working, all cylinders in the engine body 110 participate in normal operation. It should be noted that when the cylinder deactivation mechanism 120 is in operation, in order to maintain the power stability of the engine 10, the load of the remaining cylinders will be increased, so that the remaining cylinders are in a more efficient working state, thereby improving fuel economy, that is, improving the fuel consumption of the engine 10, and increasing the exhaust temperature of the engine 10.

[0034] The fuel injection system 130 can deactivate fuel injection in one or more cylinders of the engine body 10 based on control signals from the monitoring and control module 210, cooperating with the cylinder deactivation mechanism 120 to implement cylinder deactivation. Furthermore, the fuel injection system 130 can also implement a post-injection function after performing pre-injection and main injection, effectively increasing exhaust gas temperature, based on control signals from the monitoring and control module 210.

[0035] The EGR valve 140 can adjust the opening in real time according to the control signal of the monitoring control module 210, so that the exhaust gas in the exhaust pipe of the engine body 110 enters the intake system of the engine body 110 through the EGR valve 140. The exhaust gas and air are mixed and then enter the cylinder for combustion. Since part of the exhaust gas participates in the combustion, on the one hand, the exhaust temperature can be increased, and on the other hand, the combustion temperature can be reduced, thereby inhibiting the formation of nitrogen oxides in the engine exhaust gas, thereby achieving the effect of reducing the exhaust emissions of the engine 10.

[0036] The VGT supercharger 150 can adjust its opening in real time according to the control signal of the monitoring control module 210, thereby changing the intake pressure and exhaust pressure, providing the engine 10 with a suitable amount of fresh intake air and exhaust gas recirculation, and thus controlling the exhaust temperature of the engine 10.

[0037] The post-processing device 220 includes a Figure 1The second SCR, DOC, DPF and first SCR (the arrow in the middle indicates the downstream direction). Among them, the second SCR is located in the after-treatment device 220 near the VGT supercharger 150, that is, the second SCR is a pre-device for purifying NOx emissions in the engine exhaust, and the first SCR is located in the after-treatment device 220 away from the VGT supercharger 150, that is, the first SCR is the main device for purifying NOx emissions in the engine exhaust. The two SCR devices can fully treat the NOx emissions in the engine exhaust and reduce the final NOx emissions, which is a necessary configuration to cope with future emission regulations. It should be noted that the volume of the first SCR is T1, the volume of the second SCR is T2, and the relationship between the first SCR and the second SCR satisfies: 1 / 4≤T2 / T1≤1 / 2. The volume of the SCR is related to the exhaust gas purification efficiency, that is, the larger the volume of the SCR, the higher the exhaust gas purification efficiency. To reduce costs, the volume of the second SCR can be set to be smaller than the first SCR, that is, the volume of the pre-device is smaller than the volume of the main device. For example, the volume of the second SCR can be half or one-third of the volume of the first SCR.

[0038] The monitoring and control module 210 is electrically connected to the engine 10 and the after-treatment device 220, respectively. Specifically, the monitoring and control module 210 is electrically connected to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140, and the VGT supercharger 150 in the engine 10, as well as to the first and second SCRs in the after-treatment device 220. Furthermore, the monitoring and control module 210 is configured to obtain first temperature information of the first SCR and, when the first temperature information is greater than or equal to a first preset temperature, send a first control signal to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140, and the VGT supercharger 150 to operate the engine 10 in a first mode. Specifically, when the first temperature information of the first SCR is detected to be at a normal operating temperature (the first temperature information is greater than or equal to the first preset temperature), the engine 10 is switched to the first mode. In the first mode, the cylinder deactivation mechanism 120 and the VGT supercharger 150 are in an operating state. The cylinder deactivation mechanism 120 in an operating state enters a cylinder deactivation mode, deactivating some cylinders, thereby reducing fuel consumption. The EGR valve 140 is controlled to stop operating, that is, the exhaust gas from the exhaust pipe in the engine body 110 does not pass through the EGR valve 140 and enter the intake system of the engine body 110. In addition, the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism 130 are activated, and the fuel post-injection function is deactivated, thereby further reducing the fuel consumption of the engine 10.

[0039] When the monitoring control module 210 detects that the first temperature information is less than the first preset temperature, it obtains the second temperature information of the second SCR, and when the second temperature information is less than the second preset temperature, it sends a second control signal to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140, and the VGT supercharger 150, so that the engine 10 operates in the second mode. That is, when it is detected that the temperature of the after-treatment device 220 does not reach the expected temperature (the first temperature information is less than the first preset temperature and the second temperature information is less than the second preset temperature), the engine 10 is switched to operate in the second mode. In the second mode, the cylinder deactivation mechanism 120 stops operating (that is, all cylinders of the engine body 110 operate normally, and fuel consumption is relatively high at this time), the VGT supercharger 150 and the EGR valve 140 are in an operating state, and the fuel pre-injection function, the fuel main injection function, and the fuel post-injection function of the fuel injection mechanism 130 are all enabled, so that the after-treatment device 220 is quickly heated to the normal operating temperature, the conversion efficiency of the after-treatment device 220 is improved, and the generation of harmful emissions is reduced.

[0040] It is understood that the VGT supercharger 150 can provide the engine with an appropriate amount of fresh air intake and exhaust gas recirculation, thereby controlling the engine's exhaust temperature. The EGR valve 140 allows exhaust gas from the exhaust pipe of the engine body 110 to enter the engine body's 110 intake system. After the exhaust gas and air are mixed, they enter the cylinder for combustion. Since some exhaust gas participates in the combustion, the exhaust temperature can be increased. Furthermore, adding a post-fuel injection function after performing the pre-fuel injection function and the main fuel injection function can also effectively increase the exhaust temperature. Therefore, in the second mode, rapid temperature increase is achieved by deactivating the cylinder deactivation mechanism, activating the VGT supercharger and EGR valve, and adding a post-fuel injection function after performing the pre-fuel injection function and the main fuel injection function.

[0041] It should be noted that the first preset temperature is greater than the second preset temperature. The first preset temperature may be in the range of 200°C to 220°C, and the second preset temperature may be in the range of 180°C to 200°C.

[0042] In summary, embodiments of the present invention provide an exhaust gas temperature control system for an engine. The engine includes an engine body, a cylinder deactivation mechanism, a fuel injection mechanism, an EGR valve, and a VGT supercharger. The exhaust gas temperature control system includes a monitoring and control module and a post-processing device. The post-processing device includes a first SCR located remote from the VGT supercharger and a second SCR located near the VGT supercharger. The monitoring and control module is electrically connected to the engine and the post-processing device, respectively, and is configured to obtain first temperature information from the first SCR. When the first temperature information is greater than or equal to a first preset temperature, the monitoring and control module sends a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger to operate the engine in a first mode. Thus, when the first temperature information is detected to be greater than or equal to the first preset temperature, i.e., when the post-processing device is at a normal operating temperature, the engine switches to the first mode, i.e., the cylinder deactivation mechanism and the VGT supercharger are activated, the EGR valve is deactivated, the fuel injection mechanism's pre-injection and main injection functions are activated, and the post-injection function is deactivated. This improves the engine's fuel consumption primarily by enabling the cylinder deactivation mechanism to enter the cylinder deactivation mode. The monitoring and control module is also used to obtain second temperature information of the second SCR when the first temperature information is less than the first preset temperature, and to send a second control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger when the second temperature information is less than the second preset temperature, so that the engine operates in the second mode. In this way, when it is detected that the first temperature information is less than the first preset temperature and the second temperature information is less than the second preset temperature, that is, when the after-treatment device does not reach the expected temperature, the second mode is switched, that is, the cylinder deactivation mechanism is controlled to stop working, the VGT supercharger and the EGR valve are in a working state, and the fuel pre-injection function, the fuel main injection function and the fuel post-injection function of the fuel injection mechanism are all enabled, so as to quickly heat up the after-treatment device to a normal operating temperature, improve the conversion efficiency of the after-treatment device, and reduce the generation of harmful emissions.

[0043] Optionally, based on the above embodiment, continue to refer to Figure 2 The monitoring and control module 210 is further configured to obtain the oil temperature information of the engine body 110 when the second temperature information is greater than or equal to the second preset temperature, and control the engine 10 to operate in the second mode when the oil temperature information is less than a third preset temperature, and to send a third control signal to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140 and the VGT supercharger 150 when the oil temperature information is greater than or equal to the third preset temperature, so that the engine 10 operates in the third mode. In the third mode, the cylinder deactivation mechanism 120, the VGT supercharger 150 and the EGR valve 140 are all in working condition, and the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism 130 are started, and the fuel post-injection function is disabled, wherein the third preset temperature is lower than the second preset temperature.

[0044] Specifically, in the second mode, the cylinder deactivation mechanism 120 stops operating, and all cylinders in the engine body 110 are fully operational. If the engine body 110 operates in the second mode for a long time, it will have a significant impact on the engine body 110 and excessive fuel consumption. Therefore, the determination of engine oil temperature information is added to increase the transition to the third mode. Exemplarily, when it is detected that the second temperature information is greater than or equal to the second preset temperature, and the oil temperature information is less than the third temperature information, the engine 10 continues to operate in the second mode. If it is detected that the second temperature information is greater than or equal to the second preset temperature, and the oil temperature information is greater than or equal to the third preset temperature, it indicates that the after-treatment device 220 needs to be heated up, but does not need to be heated up quickly, and then the engine 10 switches from the second mode to the third mode, that is, a third control signal is sent to the cylinder deactivation mechanism 120, the fuel injection mechanism 130, the EGR valve 140 and the VGT supercharger 150, so that the engine 10 operates in the third mode. In the third mode, the cylinder deactivation mechanism 120, the VGT supercharger 150 and the EGR valve 140 are all in working condition, and the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism 130 are started, and the fuel post-injection function is disabled, so that fuel consumption can be reduced on the basis of heating.

[0045] It should be noted that the third preset temperature is lower than the second preset temperature and lower than the first preset temperature. The third preset temperature may be in the range of 40°C to 50°C.

[0046] It will be appreciated that in the first mode, the cylinder deactivation mechanism 120 determines first cylinder deactivation information based on the speed and load of the engine 110 and operates according to the first cylinder deactivation information. The first cylinder deactivation information includes a first cylinder deactivation region, a first number of deactivated cylinders, and a first cylinder deactivation combination. In the third mode, the cylinder deactivation mechanism 120 determines second cylinder deactivation information based on the speed and load of the engine 110 and operates according to the second cylinder deactivation information. The first cylinder deactivation information includes a second cylinder deactivation region, a second number of deactivated cylinders, and a second cylinder deactivation combination. Since the speed and load of the engine 110 vary between different modes, the first cylinder deactivation information in the first mode differs from the second cylinder deactivation information in the third mode. It should be noted that the cylinder deactivation combination refers to the sequence of cylinders that enter the cylinder deactivation mode when the number of deactivated cylinders is the same. For example, if the number of deactivated cylinders in a 6-cylinder engine is 2, cylinders 1 and 6 may be deactivated simultaneously, cylinders 2 and 5 may be deactivated simultaneously, or cylinders 1 and 6 and cylinders 2 and 5 may be deactivated alternately. This embodiment of the present invention is not limited to this.

[0047] Furthermore, the second cylinder deactivation area is larger than the first cylinder deactivation area. In other words, the second cylinder deactivation information is larger than the first cylinder deactivation information (the second cylinder deactivation area is larger than the first cylinder deactivation area, and the second cylinder deactivation number is larger than the first cylinder deactivation number). Specifically, in the first mode, since the main consideration is to reduce fuel consumption, the rising rate of the engine exhaust temperature is not restricted. In the third mode, the heating rate also needs to be considered. Therefore, it is necessary to set the second cylinder deactivation area larger than the first cylinder deactivation area to ensure that the heating rate is faster in the third mode. It should be noted that the size of the cylinder deactivation area represents the load rate of the engine. In the third mode, the engine load rate can be below 30%, and in the first mode, the engine load rate can be below 20%.

[0048] Optionally, based on the above embodiment, continue to participate Figure 1 When the VGT supercharger is in operation, the opening information of the VGT supercharger 150 is determined based on the speed and load of the engine body 110. The opening information of the VGT supercharger 150 in the second mode is greater than the opening information of the VGT supercharger 150 in the third mode, and the opening information of the VGT supercharger 150 in the third mode is greater than the opening information of the VGT supercharger 150 in the first mode. Specifically, the opening information of the VGT supercharger 150 reflects the flow area of ​​the VGT supercharger 150. The larger the opening information, the smaller the flow area, and further, the faster the engine exhaust temperature rises. Since the second mode is mainly for achieving rapid temperature rise, the opening information of the VGT supercharger 150 in the second mode is the largest, while the first mode is mainly for reducing fuel consumption, and therefore, the opening information of the VGT supercharger 150 in the first mode is the smallest. The third mode is a transition state between the first mode and the second mode. At this time, it is possible to reduce fuel consumption and increase temperature (the heating rate in the third mode is lower than that in the second mode). Therefore, in the third mode, the opening information of the VGT supercharger 150 is between the first mode and the second mode.

[0049] Optionally, when the EGR valve is in operation, the opening information of the EGR valve 140 is determined based on the rotational speed and load of the engine body 110. The opening information of the EGR valve 140 in the second mode is greater than the opening information of the EGR valve 140 in the third mode. Specifically, the opening information of the EGR valve 140 reflects the flow area of ​​the EGR valve 140. The larger the opening information of the EGR valve 140, the larger the flow area. Since the EGR valve 140 is used to circulate the exhaust gas in the exhaust pipe of the engine body 110 to the intake system of the engine body 110, the exhaust gas and air are mixed and then enter the cylinder for combustion, which can increase the exhaust temperature. Therefore, the larger the flow area of ​​the EGR valve 140, the faster the engine exhaust temperature rises. Therefore, the opening information of the EGR valve 140 in the second mode is set to be greater than the opening information of the EGR valve 140 in the third mode to ensure that the temperature can rise quickly in the second mode.

[0050] Optionally, based on the above embodiment, continue to refer to Figure 1 The monitoring and control module 210 includes a first temperature sensor 211, a second temperature sensor 212, a third temperature sensor 213, a fourth temperature sensor 214, and an oil temperature sensor 215. The first temperature sensor 211 is located at the outlet of the first SCR, and the second temperature sensor 212 is located at the air inlet of the first SCR. The third temperature sensor 213 is located at the outlet of the second SCR, and the fourth temperature sensor 214 is located at the air inlet of the second SCR. The monitoring and control module 210 is further configured to determine first temperature information based on the temperature information from the first temperature sensor 211 and the temperature information from the second temperature sensor 212, and to determine second temperature information based on the temperature information from the third temperature sensor 213 and the temperature information from the fourth temperature sensor 214. The oil temperature sensor 215 is located on the engine body 110.

[0051] Specifically, in one embodiment, the first temperature information may be determined based on the average of the temperature information of the first temperature sensor 211 and the temperature information of the second temperature sensor 212, and the second temperature information may be determined based on the average of the temperature information of the third temperature sensor 213 and the temperature information of the fourth temperature sensor 214. The embodiment of the present invention does not limit the specific method for determining the first temperature information and the second temperature information, and those skilled in the art may configure it as needed.

[0052] Figure 2 This is a flow chart of an engine exhaust temperature control method provided by an embodiment of the present invention. Figure 2 , the exhaust temperature control method includes:

[0053] S110 , obtaining first temperature information of a first SCR, and when the first temperature information is greater than or equal to a first preset temperature, sending a first control signal to a cylinder deactivation mechanism, a fuel injection mechanism, an EGR valve, and a VGT supercharger to operate the engine in a first mode.

[0054] In the first mode, the cylinder deactivation mechanism and the VGT supercharger are in operation, the EGR valve is deactivated, and the fuel injection mechanism's pre-injection and main-injection functions are activated, while the post-injection function is deactivated. Specifically, the engine includes multiple cylinders, each of which is connected to the cylinder deactivation mechanism. When the cylinder deactivation mechanism is in operation, the intake and exhaust valves of one or more cylinders can be deactivated and closed based on control signals from the monitoring and control module, thereby entering cylinder deactivation mode. When the cylinder deactivation mechanism is deactivated, all cylinders in the engine operate normally. It should be noted that when the cylinder deactivation mechanism is in operation, the load on the remaining cylinders is increased to maintain stable engine power, allowing them to operate more efficiently, thereby improving fuel economy, or in other words, improving engine fuel consumption. The fuel injection system can cooperate with the cylinder deactivation mechanism to implement the cylinder deactivation function. Furthermore, in the first mode, controlling the cylinder deactivation mechanism in operation and disabling the post-injection function can reduce engine fuel consumption.

[0055] S120. When the first temperature information is less than the first preset temperature, obtain the second temperature information of the second SCR, and when the second temperature information is less than the second preset temperature, send a second control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger to make the engine operate in the second mode.

[0056] In the second mode, the cylinder deactivation mechanism stops working, the VGT supercharger and the EGR valve are in working state, and the fuel pre-injection function, the fuel main injection function and the fuel post-injection function of the fuel injection mechanism are all enabled, and the first preset temperature is greater than the second preset temperature.

[0057] Specifically, the VGT supercharger can adjust its opening in real time based on control signals from the monitoring and control module, thereby changing the intake and exhaust pressures and providing the engine with the appropriate amount of fresh air and exhaust gas recirculation, thereby controlling the engine's exhaust temperature. The EGR valve can also adjust its opening in real time based on control signals from the monitoring and control module, allowing exhaust gas from the engine's exhaust pipe to pass through the EGR valve and enter the engine's intake system. The exhaust gas and air mix and then enter the cylinder for combustion. Because some exhaust gas participates in combustion, it can increase exhaust temperature. Furthermore, adding a post-fuel injection function after the pre-fuel injection and main fuel injection functions can also effectively increase exhaust temperature. Therefore, in the second mode, a rapid temperature increase is achieved by deactivating the cylinder deactivation mechanism, activating the VGT supercharger and EGR valve, and adding a post-fuel injection function after the pre-fuel injection and main fuel injection functions.

[0058] In summary, the present embodiment operates the engine in a first mode when the first temperature information is greater than or equal to a first preset temperature, with the cylinder deactivation mechanism and VGT supercharger activated, the EGR valve deactivated, the fuel injection mechanism's pilot and main fuel injection functions activated, and the post-injection function deactivated. Furthermore, when the first temperature information is less than the first preset temperature, second temperature information of the second SCR is obtained, and when the second temperature information is less than a second preset temperature, the engine is operated in a second mode, with the cylinder deactivation mechanism deactivated, the VGT supercharger and EGR valve activated, and the fuel injection mechanism's pilot, main, and post-injection functions activated. This improves engine fuel consumption in the first mode and achieves rapid temperature rise and reduced harmful emissions in the second mode.

[0059] An embodiment of the present invention further provides a vehicle, which includes the engine control system provided by any embodiment of the present invention.

[0060] Note that the above are only preferred embodiments of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments and may include many other equivalent embodiments without departing from the concept of the present invention. The scope of the present invention is determined by the scope of the appended claims.

Claims

1. An engine exhaust temperature control system, characterized in that: The engine includes an engine body, a cylinder deactivation mechanism, a fuel injection mechanism, an EGR valve, and a VGT supercharger; the exhaust temperature control system includes a monitoring control module and a post-processing device; The aftertreatment device includes a first SCR far from the VGT supercharger and a second SCR close to the VGT supercharger; The monitoring and control module is electrically connected to the engine and the after-treatment device, respectively, and is configured to obtain first temperature information of the first SCR and, when the first temperature information is greater than or equal to a first preset temperature, send a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger, so as to operate the engine in a first mode. In the first mode, the cylinder deactivation mechanism and the VGT supercharger are in an operating state, the EGR valve is deactivated, and a fuel pre-injection function and a fuel main injection function of the fuel injection mechanism are activated, and a fuel post-injection function is deactivated. The monitoring and control module is further configured to obtain second temperature information of the second SCR when the first temperature information is less than the first preset temperature, and to send a second control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger when the second temperature information is less than a second preset temperature, so as to operate the engine in a second mode. In the second mode, the cylinder deactivation mechanism stops operating, the VGT supercharger and the EGR valve are in an operating state, and a fuel pilot injection function, a fuel main injection function, and a fuel post-injection function of the fuel injection mechanism are all enabled; the first preset temperature is greater than the second preset temperature; The monitoring and control module is also used to obtain the oil temperature information of the engine body when the second temperature information is greater than or equal to the second preset temperature, and to control the engine to operate in the second mode when the oil temperature information is less than a third preset temperature, and to send a third control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger when the oil temperature information is greater than or equal to the third preset temperature, so that the engine operates in the third mode. In the third mode, the cylinder deactivation mechanism, the VGT supercharger and the EGR valve are all in working state, and the fuel pre-injection function and the fuel main injection function of the fuel injection mechanism are started, and the fuel post-injection function is disabled, wherein the third preset temperature is lower than the second preset temperature.

2. The exhaust temperature control system according to claim 1, characterized in that: In the first mode, the cylinder deactivation mechanism determines first cylinder deactivation information according to the speed and load of the engine body and operates according to the first cylinder deactivation information, wherein the first cylinder deactivation information includes a first cylinder deactivation area, a first cylinder deactivation number, and a first cylinder deactivation combination; In the third mode, the cylinder deactivation mechanism determines second cylinder deactivation information according to the speed and load of the engine body and operates according to the second cylinder deactivation information, where the second cylinder deactivation information includes a second cylinder deactivation area, a second cylinder deactivation number, and a second cylinder deactivation combination.

3. The exhaust temperature control system according to claim 2, characterized in that: The second cylinder deactivation area is larger than the first cylinder deactivation area.

4. The exhaust temperature control system according to claim 1, characterized in that: When the VGT supercharger is in an operating state, determining the opening information of the VGT supercharger according to the speed and load of the engine body; The opening information of the VGT supercharger in the second mode is greater than the opening information of the VGT supercharger in the third mode, and the opening information of the VGT supercharger in the third mode is greater than the opening information of the VGT supercharger in the first mode.

5. The exhaust temperature control system according to claim 1, characterized in that: When the EGR valve is in a working state, determining the opening information of the EGR valve according to the speed and load of the engine body; The opening degree information of the EGR valve in the second mode is greater than the opening degree information of the EGR valve in the third mode.

6. The exhaust temperature control system according to claim 1, characterized in that: The volume of the first SCR is T1, the volume of the second SCR is T2, and the relationship between the second SCR and the first SCR satisfies: 1 / 4≤ T2 / T1≤1 / 2.

7. The exhaust temperature control system according to claim 1, characterized in that: The monitoring and control module includes a first temperature sensor, a second temperature sensor, a third temperature sensor, a fourth temperature sensor and an oil temperature sensor; The first temperature sensor is disposed at the air outlet of the first SCR, and the second temperature sensor is disposed at the air inlet of the first SCR; The third temperature sensor is provided at the air outlet of the second SCR, and the fourth temperature sensor is provided at the air inlet of the second SCR; The monitoring and control module is further configured to determine the first temperature information based on the temperature information of the first temperature sensor and the temperature information of the second temperature sensor, and to determine the second temperature information based on the temperature information of the third temperature sensor and the temperature information of the fourth temperature sensor; The oil temperature sensor is arranged on the engine body.

8. A method for controlling exhaust temperature of an engine, characterized in that: Applicable to the exhaust temperature control system of the engine according to any one of claims 1 to 7; The exhaust temperature control method comprises: obtaining first temperature information of the first SCR; and, when the first temperature information is greater than or equal to a first preset temperature, sending a first control signal to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve, and the VGT supercharger to operate the engine in a first mode. In the first mode, the cylinder deactivation mechanism and the VGT supercharger are in an operating state, the EGR valve is deactivated, and the fuel pilot injection function and the fuel main injection function of the fuel injection mechanism are activated, while the fuel post-injection function is deactivated. When the first temperature information is less than the first preset temperature, second temperature information of the second SCR is obtained, and when the second temperature information is less than the second preset temperature, a second control signal is sent to the cylinder deactivation mechanism, the fuel injection mechanism, the EGR valve and the VGT supercharger to operate the engine in a second mode. In the second mode, the cylinder deactivation mechanism stops working, the VGT supercharger and the EGR valve are in working state, and the fuel pre-injection function, the fuel main injection function and the fuel post-injection function of the fuel injection mechanism are all enabled; the first preset temperature is greater than the second preset temperature.

9. A vehicle, characterized in that: An exhaust temperature control system for an engine comprising the method according to any one of claims 1 to 7.

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