A control system and control method for a vehicle, engine

Abstract

The application discloses a kind of vehicle, engine control system and control method, the control system includes: monitoring control module, cylinder deactivation control module and engine;Engine includes engine body, exhaust throttle valve, temperature detection module and aftertreatment device;Aftertreatment device includes sequentially connected first SCR, DOC, DPF and second SCR;Temperature detection module is used to detect the temperature of first SCR, the temperature of second SCR and the temperature of coolant in engine;Cylinder deactivation control module is used to control part of cylinder in engine body to stop working when working;Monitoring control module is used to control engine to enter exhaust temperature control mode when the temperature of second SCR is less than first preset temperature, for controlling engine to enter maintaining mode when the temperature of second SCR is greater than or equal to first preset temperature and the temperature of second SCR is less than second preset temperature.The application can reduce the fuel consumption of engine, and also can quickly improve the temperature of aftertreatment device.

Description

Technical Field

[0001] This invention relates to the field of engine technology, and in particular to a control system and control method for a vehicle and an engine. Background Technology

[0002] With increasing public awareness of environmental protection, vehicle emission regulations are becoming increasingly stringent. Currently, my country has implemented the National VI emission standard nationwide in phases, and even stricter emission and fuel consumption regulations are expected to be introduced after 2025. Nitrogen oxides (NOx) are one of the main emissions from diesel engines, and controlling NOx emissions primarily employs two technologies: EGR (Exhaust Gas Recirculation) and SCR (Selective Catalytic Reduction).

[0003] To meet future regulatory requirements, on the one hand, it is necessary to further adopt in-engine purification measures on the basis of China VI diesel engines to more accurately control NOx emissions from the original engine. On the other hand, it is necessary to adopt more efficient exhaust temperature thermal management technologies to improve exhaust gas temperature, such as exhaust gas heaters, burners, cylinder deactivation, intake throttle valves, and exhaust throttle valves, so that the aftertreatment system can reach the efficient temperature range as soon as possible. Summary of the Invention

[0004] This invention provides a control system and control method for a vehicle and an engine, which can reduce engine fuel consumption and rapidly increase the temperature of the aftertreatment device.

[0005] According to one aspect of the present invention, an engine control system is provided, the engine control system comprising: a monitoring and control module, a cylinder deactivation control module, and an engine;

[0006] The engine includes an engine block, an exhaust throttle valve, a temperature detection module, and an aftertreatment device; the aftertreatment device includes a first SCR, a DOC, a DPF, and a second SCR connected in sequence; wherein, the first SCR is adjacent to the exhaust port of the engine block; the temperature detection module is used to detect the temperature of the first SCR, the temperature of the second SCR, and the temperature of the coolant in the engine; the cylinder deactivation control module is used to control some cylinders in the engine block to stop working when it is in operation.

[0007] The monitoring and control module is used to control the engine to enter an exhaust temperature control mode when the temperature of the second SCR is lower than a first preset temperature, to control the engine to enter a holding mode when the temperature of the second SCR is greater than or equal to the first preset temperature and less than a second preset temperature, and to control the engine to enter an emission control mode when the temperature of the second SCR is greater than or equal to the second preset temperature; wherein the second preset temperature is greater than the first preset temperature; in the exhaust temperature control mode, the monitoring and control module is used to control the opening of the exhaust throttle valve to be less than the exhaust temperature when the temperature of the first SCR is less than a third preset temperature or the temperature of the coolant is less than a fourth preset temperature. The throttle valve is opened to its maximum opening, and the cylinder deactivation control module is stopped. When the temperature of the first SCR is greater than or equal to the third preset temperature, and the temperature of the coolant is greater than or equal to the fourth preset temperature, the exhaust throttle valve opening is controlled to be less than its maximum opening, and the cylinder deactivation control module is activated. In the holding mode, the monitoring control module controls the exhaust throttle valve opening to be equal to its minimum opening while simultaneously activating the cylinder deactivation control module. In the emission control mode, the monitoring control module controls the concentration of emissions from the engine body within a set range while simultaneously activating the cylinder deactivation control module and controlling the exhaust throttle valve opening to be equal to its minimum opening.

[0008] Optionally, in the exhaust temperature control mode, the monitoring and control module is used to determine the opening degree of the exhaust throttle valve based on the engine speed and the engine load, so that the opening degree of the exhaust throttle valve is less than the maximum opening degree of the exhaust throttle valve.

[0009] Optionally, the opening degree of the exhaust throttle valve when the engine is in a weak thermal management mode is less than the opening degree of the exhaust throttle valve when the engine is in a strong thermal management mode. Specifically, the engine is in a strong thermal management mode when the temperature of the second SCR is less than the first preset temperature and the temperature of the first SCR is less than the third preset temperature, or when the temperature of the second SCR is less than the first preset temperature and the temperature of the coolant is less than the fourth preset temperature; the engine is in a weak thermal management mode when the temperature of the second SCR is less than the first preset temperature, the temperature of the first SCR is greater than or equal to the third preset temperature, and the temperature of the coolant is greater than or equal to the fourth preset temperature.

[0010] Optionally, the engine also includes a gas detection module, an EGR valve, and a VGT turbocharger;

[0011] The emissions from the engine itself include nitrogen oxides;

[0012] The gas detection module is used to detect the concentration of nitrogen oxides emitted by the engine body;

[0013] The monitoring and control module is specifically used to determine the actual specific emission value of nitrogen oxides based on the nitrogen oxide gas concentration detected by the gas detection module when the temperature of the second SCR is greater than or equal to the second preset temperature, and to control the opening degree of the VGT turbocharger or the opening degree of the EGR valve when the actual specific emission value is greater than the preset specific emission value, so that the nitrogen oxide gas concentration emitted by the engine body is within the set range. When the actual specific emission value is less than or equal to the preset specific emission value, the module controls the opening degree of the VGT turbocharger, the opening degree of the EGR valve, the rail pressure in the engine body, or the injection advance angle in the engine body.

[0014] Optionally, the cylinder deactivation control module is used to control the number of cylinders deactivated in the engine based on the engine speed and the engine load.

[0015] Optionally, the temperature detection module includes a first temperature detection unit, a second temperature detection unit, a third temperature detection unit, and a fourth temperature detection unit.

[0016] The first temperature detection unit is located at the air inlet of the first SCR, and the first temperature detection unit is used to detect the temperature of the air inlet of the first SCR.

[0017] The second temperature detection unit is located at the outlet of the first SCR, and the second temperature detection unit is used to detect the temperature of the outlet of the first SCR.

[0018] The third temperature detection unit is located at the air inlet of the second SCR, and the third temperature detection unit is used to detect the temperature of the air inlet of the second SCR.

[0019] The fourth temperature detection unit is located at the outlet of the second SCR, and the fourth temperature detection unit is used to detect the temperature of the outlet of the second SCR.

[0020] The monitoring and control module is used to determine the temperature of the first SCR based on the temperature of the inlet of the first SCR and the temperature of the outlet of the first SCR, and is also used to determine the temperature of the second SCR based on the temperature of the inlet of the second SCR and the temperature of the outlet of the second SCR.

[0021] Optionally, the number of cylinders deactivated in the engine body when the engine is in the exhaust temperature control mode is greater than the number of cylinders deactivated in the engine body when the engine is in the holding mode.

[0022] The number of cylinders deactivated in the engine body when the engine is in the hold mode is greater than the number of cylinders deactivated in the engine body when the engine is in the emission control mode.

[0023] Optionally, the volume of the first SCR is smaller than the volume of the second SCR.

[0024] According to another aspect of the present invention, an engine control method is provided, which is applied to the engine control system provided in any embodiment of the present invention;

[0025] The engine control method includes:

[0026] Obtain the temperature of the second SCR;

[0027] Determine whether the temperature of the second SCR is lower than the first preset temperature;

[0028] If so, then control the engine to enter exhaust temperature control mode;

[0029] If not, determine whether the temperature of the second SCR is lower than the second preset temperature;

[0030] If so, the engine is controlled to enter a holding mode. In the holding mode, the opening of the exhaust throttle valve is controlled to be equal to the minimum opening of the exhaust throttle valve, and the cylinder deactivation control module is simultaneously activated.

[0031] If not, the engine is controlled to enter the emission control mode. In the emission control mode, the concentration of emissions from the engine body is controlled within a set range, while the cylinder deactivation control module is controlled to operate and the opening of the exhaust throttle valve is controlled to be equal to the minimum opening of the exhaust throttle valve.

[0032] Wherein, the second preset temperature is greater than the first preset temperature;

[0033] In the aforementioned exhaust temperature control mode:

[0034] Obtain the temperature of the first SCR and the temperature of the coolant;

[0035] Determine whether the temperature of the first SCR is lower than the third preset temperature;

[0036] If so, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to stop working;

[0037] If not, determine whether the temperature of the coolant is lower than the fourth preset temperature;

[0038] If so, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to stop working;

[0039] If not, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to operate.

[0040] According to another aspect of the present invention, a vehicle is provided that includes a control system for an engine provided in any embodiment of the present invention.

[0041] This embodiment provides an engine control system, which includes a monitoring and control module, a cylinder deactivation control module, and an engine. The engine includes an engine block, an exhaust throttle valve, and an aftertreatment device. The cylinder deactivation control module can control some cylinders in the engine block to stop working. The aftertreatment device includes a first SCR and a second SCR, which can increase the final NOx emissions in the engine exhaust. When the temperature of the second SCR is lower than a first preset temperature, the monitoring and control module controls the engine to enter an exhaust temperature control mode. In the exhaust temperature control mode, the exhaust throttle valve works alone or in conjunction with the cylinder deactivation control module, thereby significantly increasing the exhaust gas temperature and rapidly heating the aftertreatment device. When the temperature of the second SCR is greater than or equal to the first preset temperature but less than a second preset temperature, the monitoring and control module controls the engine to enter a holding mode. In the holding mode, the monitoring and control module uses the cylinder deactivation control module to increase the temperature of the aftertreatment device and controls the opening of the exhaust throttle valve to be minimized. When the temperature of the second SCR is greater than or equal to the second preset temperature, the monitoring and control module controls the concentration of engine emissions and controls the cylinder deactivation control module to work to reduce engine fuel consumption and rapidly increase the temperature of the aftertreatment device. In summary, the engine control system provided in this embodiment can reduce engine fuel consumption and also quickly increase the temperature of the aftertreatment device.

[0042] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0043] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0044] Figure 1 This is a schematic diagram of the structure of an engine control system according to an embodiment of the present invention;

[0045] Figure 2 This is a schematic flowchart of an engine control method according to an embodiment of the present invention;

[0046] Figure 3 This is a flowchart illustrating the process of an engine entering exhaust temperature control mode according to an embodiment of the present invention.

[0047] Figure 4 This is a schematic diagram of the process when an engine enters emission control mode according to an embodiment of the present invention. Detailed Implementation

[0048] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0049] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention 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 so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a 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.

[0050] Figure 1 This is a schematic diagram of the structure of an engine control system according to an embodiment of the present invention, with reference to... Figure 1 The engine control system provided in this embodiment includes: a cylinder deactivation control module 1, an engine, and a monitoring and control module 40; the engine includes an engine body 2, an exhaust throttle valve 4, a temperature detection module 10, and an aftertreatment device 30; the aftertreatment device 30 includes a first SCR 31, a DOC 32, a DPF 33, and a second SCR 34 connected in sequence; wherein, the first SCR 31 is adjacent to the exhaust port of the engine body 2; the temperature detection module 10 is used to detect the temperature of the first SCR 31, the temperature of the second SCR 34, and the temperature of the coolant in the engine; the cylinder deactivation control module 1 is used to control some cylinders in the engine body 2 to stop working when it is working.

[0051] The monitoring and control module 40 is used to control the engine to enter the exhaust temperature control mode when the temperature of the second SCR34 is lower than the first preset temperature, to control the engine to enter the holding mode when the temperature of the second SCR34 is greater than or equal to the first preset temperature and the temperature of the second SCR34 is lower than the second preset temperature, and to control the engine to enter the emission control mode when the temperature of the second SCR34 is greater than or equal to the second preset temperature.

[0052] In the exhaust temperature control mode, the monitoring and control module 40 controls the opening of the exhaust throttle valve 4 to be less than the maximum opening of the exhaust throttle valve 4 and controls the cylinder deactivation control module 40 to stop working when the temperature of the first SCR 31 is less than the third preset temperature or the temperature of the coolant is less than the fourth preset temperature; when the temperature of the first SCR 31 is greater than or equal to the third preset temperature and the temperature of the coolant is greater than or equal to the fourth preset temperature, it controls the opening of the exhaust throttle valve 4 to be less than the maximum opening of the exhaust throttle valve 4 and controls the cylinder deactivation control module 1 to work; in the holding mode, the monitoring and control module 40 controls the opening of the exhaust throttle valve 4 to be equal to the minimum opening of the exhaust throttle valve 4 and controls the cylinder deactivation control module 1 to work; in the emission control mode, the monitoring and control module 40 controls the concentration of emissions from the engine body 2 to be within a set range, controls the cylinder deactivation control module 1 to work, and controls the opening of the exhaust throttle valve 4 to be equal to the minimum opening of the exhaust throttle valve 4; wherein, the second preset temperature is greater than the first preset temperature.

[0053] Specifically, the engine in this embodiment can be a diesel engine. The monitoring and control module 40 is electrically connected to the temperature detection module 10, and the monitoring and control module 40 can obtain the temperature of the first SCR 31, the temperature of the second SCR 34, and the temperature of the coolant in the engine through the temperature detection module 10.

[0054] The cylinder deactivation control module 1 is connected to the monitoring and control module 40 and the engine block 2. Based on the instructions from the monitoring and control module 40, the cylinder deactivation control module 1 can control the intake and exhaust valves of any cylinder in the engine block 2 to stop working and be in a closed state. Simultaneously, it stops the fuel supply to that cylinder, thus achieving the cylinder deactivation function. The cylinder deactivation control module 1 can control multiple cylinders in the engine block 2 to deactivate simultaneously. Controlling some cylinders in the engine block 2 to stop working allows the engine block 2 to increase the load rate of the remaining working cylinders while maintaining the same output power, thereby effectively increasing the exhaust temperature of the engine block 2 and reducing fuel consumption under low load conditions. The more cylinders deactivated in the engine block 2, the greater the increase in exhaust temperature. When the monitoring and control module 40 controls the cylinder deactivation control module 1 to work, the cylinder deactivation control module 1 can control some cylinders in the engine block 2 to stop working; when the monitoring and control module 40 controls the cylinder deactivation control module 1 to stop working, the monitoring and control module 40 controls all cylinders in the engine block 2 to work.

[0055] The first SCR 31 and the second SCR 34 are used to purify NOx in the exhaust gas. The first SCR 31 is a pre-treatment device for purifying NOx emissions in the exhaust gas, and the second SCR 34 is the main device for purifying NOx emissions in the exhaust gas. The two SCRs can fully treat the NOx emissions in the exhaust gas of the engine body 2, reducing the final NOx emissions. When the gas after combustion in the engine body 2 passes through the honeycomb carrier in DOC 32, it is adsorbed by the platinum group metal coated on the surface of the carrier. At the same time, the platinum group metal acts as a catalyst, and together with the adsorbed oxygen, it oxidizes and burns the carbon monoxide and hydrocarbon gases in the exhaust gas of the engine body 2, turning them into carbon dioxide and water, which have little impact on the environment. DPF 33 can filter out and capture particulate matter before it enters the atmosphere. DPF 33 can reduce the soot produced by the engine body 2 by more than 90%. The captured particulate matter is then completely burned, thereby reducing the direct emission of these particles into the atmosphere and improving the quality of engine exhaust emissions.

[0056] The monitoring and control module 40 is connected to the exhaust throttle valve 4, and the monitoring and control module 40 can control the opening degree of the exhaust throttle valve 4. The exhaust throttle valve 4 is located between the exhaust port of the engine body 2 and the first SCR 31. When the opening degree of the exhaust throttle valve 4 is less than the maximum opening degree of the exhaust throttle valve 4, the exhaust throttle valve 4 can reduce the exhaust flow cross-sectional area under cold start and low load conditions of the engine body 2, thereby effectively increasing the exhaust temperature and enabling the aftertreatment device 30 to heat up quickly.

[0057] The first preset temperature range can be 180℃~190℃, the second preset temperature range can be 220℃~240℃, the third preset temperature range can be 170℃~180℃, and the fourth preset temperature range can be 35℃~45℃.

[0058] Since the second SCR34 is the main device for purifying NOx emissions from the exhaust gas, the temperature of the aftertreatment device 30 is primarily determined by the temperature of the second SCR34. When the temperature of the second SCR34 is lower than the first preset temperature, it indicates that the engine is in a cold start condition, and the engine is controlled to enter the exhaust temperature control mode. In the exhaust temperature control mode, if the monitoring and control module 40 detects that the temperature of the first SCR31 ​​is lower than the third preset temperature or the temperature of the coolant in the engine is lower than the fourth set temperature, it indicates that the engine is still in a cold start condition. At this time, the monitoring and control module 40 controls the opening of the exhaust throttle valve 4 to be less than the maximum opening of the exhaust throttle valve, so as to reduce the exhaust flow cross-sectional area and thus increase the exhaust temperature, allowing the aftertreatment device 30 to heat up quickly. At the same time, the monitoring and control module 40 controls the cylinder deactivation control module 1 to not work, even if all cylinders in the engine body 2 are working, thereby preventing the cylinder deactivation control module 1 from working when the engine is in a cold start condition. In the exhaust temperature control mode, if the monitoring and control module 40 detects that the temperature of the first SCR 31 is greater than or equal to the third preset temperature and the temperature of the coolant in the engine is greater than or equal to the fourth set temperature, it indicates that the engine temperature is not particularly low. The monitoring and control module 40 can control the opening of the exhaust throttle valve 4 to be less than the maximum opening of the exhaust throttle valve 4 and control the cylinder deactivation control module 1 to work, so that the exhaust throttle valve 4 and the cylinder deactivation control module 1 work together, thereby significantly increasing the exhaust gas temperature, allowing the aftertreatment device 30 to heat up quickly, and reducing the engine's fuel consumption.

[0059] In the hold mode, the monitoring and control module 40 controls the opening of the exhaust throttle valve 4 to be equal to its minimum opening, i.e., the exhaust throttle valve 4 is stopped from being used, thus not increasing the engine's fuel consumption. At the same time, the monitoring and control module 40 controls the cylinder deactivation control module 1 to operate, i.e., controls some cylinders in the engine body 2 to stop working, thereby increasing the temperature of the aftertreatment device 30 and reducing the engine's fuel consumption.

[0060] When the temperature of the second SCR34 is greater than or equal to the second preset temperature, the temperature of the aftertreatment device 30 is within the normal temperature range. At this time, the concentration of NOx emitted by the engine body 2 is controlled within a set range according to the concentration of NOx emitted by the engine body 2, thereby reducing the emission of pollutants from the engine. Simultaneously, the monitoring and control module 40 controls the cylinder deactivation control module 1 to operate, that is, controls some cylinders in the engine body 2 to stop working, thereby increasing the temperature of the aftertreatment device 30 and reducing engine fuel consumption. Furthermore, the monitoring and control module 40 controls the opening of the exhaust throttle valve 4 to be equal to the minimum opening of the exhaust throttle valve 4, that is, stops using the exhaust throttle valve 4, thereby not increasing engine fuel consumption.

[0061] This embodiment provides an engine control system, which includes a monitoring and control module, a cylinder deactivation control module, and an engine. The engine includes an engine block, an exhaust throttle valve, and an aftertreatment device. The cylinder deactivation control module can control some cylinders in the engine block to stop working. The aftertreatment device includes a first SCR and a second SCR, which can increase the final NOx emissions in the engine exhaust. When the temperature of the second SCR is lower than a first preset temperature, the monitoring and control module controls the engine to enter an exhaust temperature control mode. In the exhaust temperature control mode, the exhaust throttle valve works alone or in conjunction with the cylinder deactivation control module, thereby significantly increasing the exhaust gas temperature and rapidly heating the aftertreatment device. When the temperature of the second SCR is greater than or equal to the first preset temperature but less than a second preset temperature, the monitoring and control module controls the engine to enter a holding mode. In the holding mode, the monitoring and control module uses the cylinder deactivation control module to increase the temperature of the aftertreatment device and controls the opening of the exhaust throttle valve to be minimized. When the temperature of the second SCR is greater than or equal to the second preset temperature, the monitoring and control module controls the concentration of engine emissions and controls the cylinder deactivation control module to work to reduce engine fuel consumption and rapidly increase the temperature of the aftertreatment device. In summary, the engine control system provided in this embodiment can reduce engine fuel consumption and also quickly increase the temperature of the aftertreatment device.

[0062] Optionally, in exhaust temperature control mode, the monitoring and control module is used to determine the opening of the exhaust throttle valve based on the engine speed and engine load, so that the opening of the exhaust throttle valve is less than the maximum opening of the exhaust throttle valve.

[0063] Specifically, the monitoring and control module can first obtain the engine speed and engine load, then look up the corresponding exhaust throttle valve opening in the engine speed and load table based on the engine speed and engine load, and adjust the exhaust throttle valve opening to the corresponding opening.

[0064] Optionally, the opening of the exhaust throttle valve in the weak thermal management mode is less than the opening of the exhaust throttle valve in the strong thermal management mode. Specifically, the engine is in strong thermal management mode when the temperature of the second SCR is less than the first preset temperature and the temperature of the first SCR is less than the third preset temperature, or when the temperature of the second SCR is less than the first preset temperature and the temperature of the coolant is less than the fourth preset temperature; the engine is in weak thermal management mode when the temperature of the second SCR is less than the first preset temperature, the temperature of the first SCR is greater than or equal to the third preset temperature, and the temperature of the coolant is greater than or equal to the fourth preset temperature.

[0065] Specifically, in strong thermal management mode, the monitoring and control module increases the temperature of the aftertreatment unit by controlling the opening of the exhaust throttle valve, without using the cylinder deactivation control module. Therefore, in strong thermal management mode, the opening of the exhaust throttle valve is greater than in weak thermal management mode, allowing for a rapid increase in the aftertreatment unit's temperature. In weak thermal management mode, the monitoring and control module increases the aftertreatment unit's temperature by controlling the opening of the exhaust throttle valve and the operation of the cylinder deactivation control module. In this case, the opening of the exhaust throttle valve is smaller, minimizing the increase in engine fuel consumption.

[0066] In strong heat management mode, the monitoring and control module can control more operating areas using the exhaust throttle valve, while in weak heat management mode, the monitoring and control module can control fewer operating areas using the exhaust throttle valve.

[0067] Optional, continue to refer to Figure 1 The engine also includes a gas detection module 21, an EGR valve 5, and a VGT turbocharger 3; the emissions from the engine body 2 include nitrogen oxides; the gas detection module 21 is used to detect the concentration of nitrogen oxides emitted by the engine body 2; the monitoring and control module 40 is specifically used to determine the actual specific emission value of nitrogen oxides based on the gas concentration of nitrogen oxides detected by the gas detection module 21 when the temperature of the second SCR 34 is greater than or equal to the second preset temperature, and to control the opening of the VGT turbocharger 3 or the opening of the EGR valve 5 when the actual specific emission value is greater than the preset specific emission value, so that the concentration of nitrogen oxides emitted by the engine body is within the set range, and to control the opening of the VGT turbocharger 3, the opening of the EGR valve 5, the rail pressure in the engine body 2, or the injection advance angle in the engine body 2 when the actual specific emission value is less than or equal to the preset specific emission value.

[0068] Specifically, the engine also includes an EGR cooler 6. The opening of the VGT turbocharger 3 can be adjusted in real time according to the needs of the engine block 2, thereby changing the intake and exhaust pressures of the engine block 2 and providing the engine block 2 with a suitable amount of fresh intake air and exhaust gas recirculation. The EGR valve 5 can allow the exhaust gas in the exhaust pipe of the engine block 2 to re-enter the intake system of the engine block 2 through the EGR valve 5. After the exhaust gas and air are mixed, they enter the cylinder for combustion. Since some exhaust gas participates in combustion, it can effectively suppress the formation of nitrogen oxides in the engine exhaust gas, thereby reducing engine exhaust emissions. The gas detection module 21 is located at the intake port of the first SCR 31, which can improve the accuracy of the gas detection module 21. The gas detection module 21 can be a gas sensor.

[0069] When the temperature of the second SCR34 is greater than or equal to the second preset temperature, the monitoring and control module 40 controls the cylinder deactivation control module 1 to operate. The purpose of using the cylinder deactivation control module 1 at this time is to save engine fuel consumption. However, while improving fuel economy, the cylinder deactivation control module 1 may also cause changes in the actual specific emission value of the engine body 2. Therefore, in order to reduce engine fuel consumption, it is necessary to control the concentration of nitrogen oxides emitted by the engine body 2. The monitoring and control module 40 is electrically connected to the gas detection module 21. The monitoring and control module 40 acquires the concentration of nitrogen oxides emitted by the engine body 2 detected by the gas detection module 21 and combines it with the exhaust flow rate of the engine body 2 to obtain the actual specific emission value. When the actual specific emission value is greater than the preset specific emission value, the monitoring and control module 40 controls the opening of the VGT turbocharger 3 or the opening of the EGR valve 5 to reduce the concentration of nitrogen oxides emitted by the engine body 2. When the actual specific emission value is less than or equal to the preset specific emission value, the monitoring and control module 40 controls the opening degree of the VGT turbocharger 3, the opening degree of the EGR valve 5, the rail pressure in the engine body 2, or the injection advance angle in the engine body 2 to reduce the engine's fuel consumption.

[0070] It should be noted that when the concentration of nitrogen oxides is within the set range, the actual specific emission value can be less than or equal to the preset specific emission value.

[0071] Optionally, the cylinder deactivation control module is used to control the number of cylinders deactivated in the engine based on the engine speed and engine load during operation.

[0072] Specifically, when the monitoring and control module obtains the engine speed and engine load, it looks up the corresponding number of cylinder deactivation in the engine speed and load table based on the engine speed and engine load, and controls the number of cylinder deactivation in the engine body to be the corresponding number of cylinder deactivation.

[0073] Optional, continue to refer to Figure 1The temperature detection module 10 includes a first temperature detection unit 11, a second temperature detection unit 12, a third temperature detection unit 13, and a fourth temperature detection unit 14. The first temperature detection unit 11 is located at the air inlet of the first SCR 31 and is used to detect the temperature of the air inlet of the first SCR 31. The second temperature detection unit 12 is located at the air outlet of the first SCR 31 and is used to detect the temperature of the air outlet of the first SCR 31. The third temperature detection unit 13 is located at the air inlet of the second SCR 34. The third temperature detection unit 13 is used to detect the temperature of the air inlet of the second SCR34; the fourth temperature detection unit 14 is located at the air outlet of the second SCR34 and is used to detect the temperature of the air outlet of the second SCR34; the monitoring and control module 40 is used to determine the temperature of the first SCR31 ​​based on the temperature of the air inlet of the first SCR31 ​​and the temperature of the air outlet of the first SCR31, and is also used to determine the temperature of the second SCR34 based on the temperature of the air inlet of the second SCR34 and the temperature of the air outlet of the second SCR34.

[0074] Specifically, the first temperature detection unit 11, the second temperature detection unit 12, the third temperature detection unit 13, and the fourth temperature detection unit 14 can all be temperature sensors. The monitoring and control module is electrically connected to the first temperature detection unit 11, the second temperature detection unit 12, the third temperature detection unit 13, and the fourth temperature detection unit 14. The monitoring and control module can acquire the temperatures detected by the first temperature detection unit 11, the second temperature detection unit 12, the third temperature detection unit 13, and the fourth temperature detection unit 14. The monitoring and control module can determine the temperature of the first SCR based on the average of the temperatures detected by the first and second temperature detection units, and can also determine the temperature of the second SCR based on the average of the temperatures detected by the third and fourth temperature detection units.

[0075] Optional, continue to refer to Figure 1 The number of cylinders shut down in the engine body when the engine is in exhaust temperature control mode is greater than the number of cylinders shut down in the engine body when the engine is in hold mode; the number of cylinders shut down in the engine body when the engine is in hold mode is greater than the number of cylinders shut down in the engine body when the engine is in emission control mode. This setting allows the aftertreatment device to heat up quickly in exhaust temperature control mode and reduces fuel consumption in hold mode and emission control mode.

[0076] Optionally, the volume of the first SCR is smaller than that of the second SCR. This configuration can reduce the cost of the first SCR, thereby reducing the cost of manufacturing the engine's control system.

[0077] This embodiment provides an engine control method, which can be applied to the engine control system provided in any embodiment of the present invention.

[0078] Figure 2 This is a flowchart illustrating an engine control method according to an embodiment of the present invention. (Refer to...) Figure 2 The engine control method includes the following steps:

[0079] S110, Obtain the temperature of the second SCR.

[0080] S120. Determine whether the temperature of the second SCR is lower than the first preset temperature;

[0081] If yes, proceed to step S130; otherwise, proceed to step S140.

[0082] S130, control the engine to enter exhaust temperature control mode.

[0083] S140. Determine whether the temperature of the second SCR is lower than the second preset temperature.

[0084] If yes, proceed to step S150; otherwise, proceed to step S160.

[0085] S150: Control the engine to enter the holding mode. In the holding mode, control the opening of the exhaust throttle valve to be equal to the minimum opening of the exhaust throttle valve, and simultaneously control the cylinder deactivation control module to work.

[0086] S160: Control the engine to enter the emission control mode. In the emission control mode, control the concentration of emissions from the engine body within the set range, control the cylinder deactivation control module to work, and control the opening of the exhaust throttle valve to be equal to the minimum opening of the exhaust throttle valve.

[0087] The second preset temperature is greater than the first preset temperature.

[0088] Figure 3 This is a flowchart illustrating the process of an engine entering exhaust temperature control mode according to an embodiment of the present invention. (Refer to...) Figure 3 The exhaust temperature control mode specifically includes the following steps:

[0089] S131. Obtain the temperature of the first SCR and the temperature of the coolant.

[0090] S132. Determine whether the temperature of the first SCR is lower than the third preset temperature.

[0091] If yes, proceed to step S133; otherwise, proceed to step S134.

[0092] S133, Control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to stop working.

[0093] S134. Determine whether the temperature of the coolant is lower than the fourth preset temperature.

[0094] If yes, proceed to step S133; otherwise, proceed to step S135.

[0095] S135, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to work.

[0096] Figure 4 This is a schematic diagram of an engine entering emission control mode according to an embodiment of the present invention, with reference to... Figure 4 The emission control mode specifically includes the following steps:

[0097] S161, control the operation of the cylinder deactivation control module and control the opening degree of the exhaust throttle valve to be equal to the minimum opening degree of the exhaust throttle valve.

[0098] S162. Obtain the concentration of nitrogen oxides emitted by the engine itself.

[0099] S163. Determine the actual specific emission value of nitrogen oxides based on the gaseous concentration of nitrogen oxides.

[0100] S164. Determine whether the actual ratio emission value is greater than the preset ratio emission value.

[0101] If yes, proceed to step S165; otherwise, proceed to step S166.

[0102] S165, control the opening of the VGT turbocharger or the EGR valve to keep the concentration of nitrogen oxides emitted by the engine within a set range.

[0103] S166 controls the opening degree of the VGT turbocharger, the opening degree of the EGR valve, the rail pressure in the engine block, or the injection advance angle in the engine block.

[0104] The engine control method provided in this embodiment has the same beneficial effects as the engine control device provided in any embodiment of the present invention. For technical details not covered in this embodiment, please refer to the engine control device provided in any embodiment of the present invention.

[0105] This embodiment also provides a vehicle that includes the engine control system provided in any embodiment of the present invention.

[0106] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0107] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A control system for an engine, characterized in that, include: Monitoring and control module, cylinder deactivation control module, and engine; The engine includes an engine block, an exhaust throttle valve, a temperature detection module, and an aftertreatment device; the aftertreatment device includes a first SCR, a DOC, a DPF, and a second SCR connected in sequence; wherein, the first SCR is adjacent to the exhaust port of the engine block; the temperature detection module is used to detect the temperature of the first SCR, the temperature of the second SCR, and the temperature of the coolant in the engine; the cylinder deactivation control module is used to control some cylinders in the engine block to stop working when it is in operation. The monitoring and control module is used to control the engine to enter an exhaust temperature control mode when the temperature of the second SCR is lower than a first preset temperature; to control the engine to enter a holding mode when the temperature of the second SCR is greater than or equal to the first preset temperature and less than a second preset temperature; and to control the engine to enter an emission control mode when the temperature of the second SCR is greater than or equal to the second preset temperature; wherein the second preset temperature is greater than the first preset temperature; in the exhaust temperature control mode, the monitoring and control module is used to control the opening of the exhaust throttle valve to be less than the maximum opening of the exhaust throttle valve and to control the cylinder deactivation control module to stop working when the temperature of the first SCR is less than a third preset temperature or the temperature of the coolant is less than a fourth preset temperature; When the temperature of the first SCR is greater than or equal to the third preset temperature, and the temperature of the coolant is greater than or equal to the fourth preset temperature, the opening of the exhaust throttle valve is controlled to be less than the maximum opening of the exhaust throttle valve, and the cylinder deactivation control module is controlled to operate. In the holding mode, the monitoring control module controls the opening of the exhaust throttle valve to be equal to the minimum opening of the exhaust throttle valve, stops using the exhaust throttle valve, thereby not increasing the engine's fuel consumption, and simultaneously controls the cylinder deactivation control module to operate. In the emission control mode, the monitoring control module controls the concentration of emissions from the engine body within a set range, simultaneously controls the cylinder deactivation control module to operate and controls the opening of the exhaust throttle valve to be equal to the minimum opening of the exhaust throttle valve, stops using the exhaust throttle valve, thereby not increasing the engine's fuel consumption. The opening degree of the exhaust throttle valve when the engine is in a weak thermal management mode is less than the opening degree of the exhaust throttle valve when the engine is in a strong thermal management mode. Specifically, the engine is in a strong thermal management mode when the temperature of the second SCR is less than the first preset temperature and the temperature of the first SCR is less than the third preset temperature, or when the temperature of the second SCR is less than the first preset temperature and the temperature of the coolant is less than the fourth preset temperature. The engine is in a weak thermal management mode when the temperature of the second SCR is less than the first preset temperature, the temperature of the first SCR is greater than or equal to the third preset temperature, and the temperature of the coolant is greater than or equal to the fourth preset temperature. The number of cylinders deactivated in the engine body when the engine is in the exhaust temperature control mode is greater than the number of cylinders deactivated in the engine body when the engine is in the hold mode. The number of cylinders deactivated in the engine body when the engine is in the hold mode is greater than the number of cylinders deactivated in the engine body when the engine is in the emission control mode.

2. The engine control system according to claim 1, characterized in that, In the exhaust temperature control mode, the monitoring and control module is used to determine the opening degree of the exhaust throttle valve based on the engine speed and the engine load, so that the opening degree of the exhaust throttle valve is less than the maximum opening degree of the exhaust throttle valve.

3. The engine control system according to claim 1, characterized in that, The engine also includes a gas detection module, an EGR valve, and a VGT turbocharger; The emissions from the engine itself include nitrogen oxides; The gas detection module is used to detect the concentration of nitrogen oxides emitted by the engine body; The monitoring and control module is specifically used to determine the actual specific emission value of nitrogen oxides based on the nitrogen oxide gas concentration detected by the gas detection module when the temperature of the second SCR is greater than or equal to the second preset temperature, and to control the opening degree of the VGT turbocharger or the opening degree of the EGR valve when the actual specific emission value is greater than the preset specific emission value, so that the nitrogen oxide gas concentration emitted by the engine body is within the set range. When the actual specific emission value is less than or equal to the preset specific emission value, the module controls the opening degree of the VGT turbocharger, the opening degree of the EGR valve, the rail pressure in the engine body, or the injection advance angle in the engine body.

4. The engine control system according to claim 1, characterized in that, When the cylinder deactivation control module is in operation, it is used to control the number of cylinders deactivated in the engine based on the engine speed and the engine load.

5. The engine control system according to claim 1, characterized in that, The temperature detection module includes a first temperature detection unit, a second temperature detection unit, a third temperature detection unit, and a fourth temperature detection unit; The first temperature detection unit is located at the air inlet of the first SCR, and the first temperature detection unit is used to detect the temperature of the air inlet of the first SCR. The second temperature detection unit is located at the outlet of the first SCR, and the second temperature detection unit is used to detect the temperature of the outlet of the first SCR. The third temperature detection unit is located at the air inlet of the second SCR, and the third temperature detection unit is used to detect the temperature of the air inlet of the second SCR. The fourth temperature detection unit is located at the outlet of the second SCR, and the fourth temperature detection unit is used to detect the temperature of the outlet of the second SCR. The monitoring and control module is used to determine the temperature of the first SCR based on the temperature of the inlet of the first SCR and the temperature of the outlet of the first SCR, and is also used to determine the temperature of the second SCR based on the temperature of the inlet of the second SCR and the temperature of the outlet of the second SCR.

6. The engine control system according to claim 1, characterized in that, The volume of the first SCR is smaller than the volume of the second SCR.

7. A method for controlling an engine, characterized in that, Applied to the control system of the engine according to any one of claims 1-6; The engine control method includes: Obtain the temperature of the second SCR; Determine whether the temperature of the second SCR is lower than the first preset temperature; If so, then control the engine to enter exhaust temperature control mode; If not, determine whether the temperature of the second SCR is lower than the second preset temperature; If so, the engine is controlled to enter a holding mode. In the holding mode, the opening of the exhaust throttle valve is controlled to be equal to the minimum opening of the exhaust throttle valve, and the cylinder deactivation control module is simultaneously activated. If not, the engine is controlled to enter the emission control mode. In the emission control mode, the concentration of emissions from the engine body is controlled within a set range, while the cylinder deactivation control module is controlled to operate and the opening of the exhaust throttle valve is controlled to be equal to the minimum opening of the exhaust throttle valve. Wherein, the second preset temperature is greater than the first preset temperature; In the aforementioned exhaust temperature control mode: Obtain the temperature of the first SCR and the temperature of the coolant; Determine whether the temperature of the first SCR is lower than the third preset temperature; If so, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to stop working; If not, determine whether the temperature of the coolant is lower than the fourth preset temperature; If so, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to stop working; If not, control the opening degree of the exhaust throttle valve to be less than the maximum opening degree of the exhaust throttle valve and control the cylinder deactivation control module to operate.

8. A vehicle, characterized in that, The control system of the engine as described in any one of claims 1-6.

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