Adaptive engine exhaust temperature management control method

Abstract

This invention relates to the field of engine control system technology and discloses an adaptive engine exhaust temperature management control method. During engine bench development, calibration work is completed under the engine's normal operating mode according to the development goals. Based on the target exhaust temperature of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, the temperature improvement effect of each exhaust temperature thermal management mode is sequentially increased. Temperature limits are set for each exhaust temperature thermal management mode as its entry and exit temperatures. The predicted SCR inlet temperature is compared with the entry and exit temperatures of each exhaust temperature thermal management mode to ensure the engine enters the appropriate exhaust temperature thermal management mode. This invention's adaptive engine exhaust temperature management control method switches between different exhaust temperature thermal management modes based on the target temperature setting difference, reducing fuel consumption while meeting exhaust temperature targets.

Description

Technical Field

[0001] This invention relates to the field of engine control system technology, and specifically to an adaptive engine exhaust temperature management and control method. Background Technology

[0002] With the upgrading of vehicle emission regulations, engine emission requirements are becoming increasingly stringent. For diesel engines, the main emissions are NOx and particulate matter (PM). After-treatment typically uses SCR (Selective Catalytic Reduction) to reduce NOx emissions to meet emission regulations.

[0003] The core of SCR technology lies in injecting automotive urea into the SCR system at a controlled rate to react with NOx, thereby reducing NOx emissions to meet regulatory requirements. However, due to its physical properties, automotive urea requires temperatures above 180°C to hydrolyze. Therefore, the aftertreatment SCR system must rapidly raise the temperature to above 180°C to meet the requirements for urea injection.

[0004] Temperature is one of the main factors affecting SCR efficiency. In the China VI emission standard stage, in order to reach the urea injection temperature as soon as possible and improve the SCR conversion efficiency, manufacturers generally use the Exhaust Gas Temperature Management (EGTM) mode to increase the temperature in the low-temperature stage of engine exhaust temperature, so as to meet the urea injection temperature requirements and improve the SCR conversion efficiency.

[0005] The current solution is to calibrate an exhaust temperature thermal management mode for the engine based on the target temperature, and then switch between the engine exhaust temperature thermal management mode and the normal operating mode based on the SCR temperature to achieve rapid warm-up.

[0006] The main way exhaust thermal management increases exhaust temperature is by adjusting engine rail pressure, timing, throttle body, EGR valve, etc. While increasing exhaust temperature, it inevitably leads to increased fuel consumption. The more obvious the temperature increase, the more obvious the fuel consumption deterioration. Therefore, fuel consumption and exhaust temperature increase are relatively contradictory. According to experimental verification results, the higher the WHTC cycle temperature under exhaust thermal management mode, the worse the fuel consumption is while achieving the same emission effect.

[0007] In addition, the current thermal management mode has fixed calibration parameters, which cannot be adjusted according to the ambient temperature and SCR target temperature in actual application. Therefore, the fuel consumption is relatively high in actual use.

[0008] Chinese Patent (Publication Date: November 29, 2022, Publication No.: CN115405403A) discloses a temperature control method, device, electronic device, and storage medium to improve engine thermal management efficiency and reduce fuel consumption. The method includes: heating the engine exhaust based on the current heating mode and acquiring the upstream temperature and exhaust temperature of the selective catalytic reduction reactor (SCR); based on the SCR upstream temperature and exhaust temperature, after determining that a mode switch is needed, switching the current heating mode to the next heating mode to heat the exhaust. Different heating modes have different mode switching conditions and different fuel consumption. This application improves engine thermal management efficiency and reduces fuel consumption by monitoring the SCR upstream temperature and exhaust temperature and promptly switching the heating mode when a mode switch is needed. However, this method is based on the SCR upstream temperature and exhaust temperature, resulting in a delayed response and unclear definition of the thermal mode.

[0009] Chinese Patent (Publication Date: May 18, 2021, Publication No.: CN112814768A) discloses an SCR thermal management method and system, including: Step S1, detecting and determining whether the SCR temperature is higher than a first preset threshold; if yes, exiting thermal management; if no, proceeding to Step S2; Step S2, detecting and determining whether the vehicle is in a reduced load condition; if yes, controlling the execution of a heat preservation mode and returning to the execution of Step S1; if no, proceeding to Step S3; Step S3, detecting and determining whether the SCR temperature is higher than a second preset threshold; if yes, controlling the execution of a first temperature-increasing mode to increase the SCR temperature and returning to the execution of Step S1; if no, controlling the execution of a second temperature-increasing mode to increase the SCR temperature and returning to the execution of Step S1. The fuel consumption rate gradually decreases from the second temperature-increasing mode to the first temperature-increasing mode and then to the heat preservation mode, with the temperature-increasing speed of the second temperature-increasing mode being greater than that of the first temperature-increasing mode. This invention can reduce the sacrifice of fuel consumption rate while achieving reasonable control of the SCR temperature. However, this method requires real-time acquisition of SCR temperature, has a reaction lag, and the thermal mode is not clearly defined. Summary of the Invention

[0010] The purpose of this invention is to address the shortcomings of the aforementioned technologies by providing an adaptive engine exhaust temperature management and control method. Based on the target exhaust temperature of the WHTC cycle emission test bench, different exhaust temperature thermal management modes are developed, and the method switches between different exhaust temperature thermal management modes according to the target temperature, thereby reducing fuel consumption while meeting the exhaust temperature target.

[0011] To achieve the above objectives, the adaptive engine exhaust temperature management and control method designed in this invention, during the engine bench development process, completes the calibration work under the normal engine operation mode according to the development goals, so that emissions can meet the original engine emission engineering target requirements while achieving optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed, and the average exhaust temperature set in the WHTC cycle is used as the benchmark, which are respectively denoted as EGTM1, EGTM2, EGTM3, ... EGTM n The temperature enhancement effect of each exhaust temperature thermal management mode increases sequentially. A temperature limit is set for each exhaust temperature thermal management mode as the entry and exit temperature of that mode. The predicted temperature of the SCR inlet is compared with the entry and exit temperatures of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0012] Preferably, the temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine.

[0013] Preferably, there is an overlapping hysteresis interval between the temperature limit of the entry temperature of one exhaust temperature thermal management mode and the temperature limit of the exit temperature of the previous exhaust temperature thermal management mode, so as to avoid temperature fluctuations during the switching temperature difference and the continuous switching between the two exhaust temperature thermal management modes.

[0014] Preferably, the engine's combustion control parameters are set with a time lag or slope limit to ensure smoothness between mode switching and avoid sudden combustion changes.

[0015] Preferably, the predicted SCR inlet temperature is calculated based on the DOC inlet temperature, the specific heat capacities of DOC and DPF, and the heat loss of the SCR mixer.

[0016] Preferably, after the engine starts, the enable conditions for the engine to enter the exhaust temperature thermal management mode are determined based on the predicted temperature at the SCR inlet. If the enable conditions are not met, the engine continues to operate in normal mode until the conditions are met, at which point the exhaust temperature thermal management mode is determined and selected.

[0017] Preferably, if the enabling conditions are met, the corresponding exhaust temperature thermal management mode is entered by matching the current predicted SCR inlet temperature with the entry and exit temperatures of each exhaust temperature thermal management mode.

[0018] Preferably, when the predicted SCR inlet temperature increases, it is compared with the inlet and outlet temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the next exhaust temperature thermal management mode is entered.

[0019] Preferably, the engine enters normal mode when the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode.

[0020] Preferably, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode is determined.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] 1. Based on the difference between the predicted and target values ​​of the SCR inlet temperature, switch between different exhaust temperature thermal management modes to reduce fuel consumption while meeting the exhaust temperature target;

[0023] 2. It can adjust parameters according to ambient temperature and the target temperature of SCR inlet, further reducing fuel consumption;

[0024] 3. After warming up to normal mode, if you re-enter exhaust temperature thermal management mode, the multi-stage exhaust temperature thermal management mode can effectively reduce the impact of engine parameter adjustments on driving experience and improve driving comfort. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the process of selecting the exhaust temperature thermal management mode after engine startup in the adaptive engine exhaust temperature management control method of the present invention. Detailed Implementation

[0026] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0029] Example 1

[0030] An adaptive engine exhaust temperature management and control method is proposed. During the engine bench development process, calibration work is completed under the normal operating mode of the engine according to the development goals, so that the emissions can meet the original engine emission engineering target requirements and achieve optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, they are denoted as EGTM1, EGTM2, and EGTM3, respectively. The temperature improvement effect of each exhaust temperature thermal management mode increases sequentially. Temperature limits are set for each exhaust temperature thermal management mode as the entry temperature and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry temperature and exit temperature of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0031] In this embodiment, as Figure 1 As shown, after the engine starts, the engine enters the exhaust temperature thermal management mode based on the predicted temperature of the SCR inlet. If the enabling conditions are not met, the engine continues to operate in normal mode until the conditions are met, at which point the exhaust temperature thermal management mode is determined and selected.

[0032] If the enabling conditions are met, the current predicted SCR inlet temperature is compared with the target SCR inlet temperature. Based on the temperature difference and the entry and exit temperatures of each exhaust temperature thermal management mode, the corresponding exhaust temperature thermal management mode is entered. For example, if the predicted SCR inlet temperature is lower than the exit temperature of EGTM1, then EGTM1 is entered; if the predicted SCR inlet temperature is lower than the exit temperature of EGTM2, then EGTM2 is entered.

[0033] In addition, when the predicted SCR inlet temperature rises, it is compared with the entry and exit temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the engine enters the next exhaust temperature thermal management mode until the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, at which point the engine enters normal mode.

[0034] Finally, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

[0035] Example 2

[0036] An adaptive engine exhaust temperature management and control method is proposed. During the engine bench development process, calibration work is completed under the normal operating mode of the engine according to the development goals, so that the emissions can meet the original engine emission engineering target requirements and achieve optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, they are denoted as EGTM1, EGTM2, and EGTM3, respectively. The temperature improvement effect of each exhaust temperature thermal management mode increases sequentially. Temperature limits are set for each exhaust temperature thermal management mode as the entry temperature and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry temperature and exit temperature of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0037] The temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine.

[0038] In this embodiment, after the engine starts, the enable condition for the engine to enter the exhaust temperature thermal management mode is determined based on the predicted temperature of the SCR inlet. If the enable condition is not met, the engine continues to operate in normal mode until the condition is met, and then the exhaust temperature thermal management mode is determined and selected.

[0039] If the enabling conditions are met, the current predicted SCR inlet temperature is compared with the target SCR inlet temperature. Based on the temperature difference and the entry and exit temperatures of each exhaust temperature thermal management mode, the corresponding exhaust temperature thermal management mode is entered. For example, if the predicted SCR inlet temperature is lower than the exit temperature of EGTM1, then EGTM1 is entered; if the predicted SCR inlet temperature is lower than the exit temperature of EGTM2, then EGTM2 is entered.

[0040] In addition, when the predicted SCR inlet temperature rises, it is compared with the entry and exit temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the engine enters the next exhaust temperature thermal management mode until the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, at which point the engine enters normal mode.

[0041] Finally, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

[0042] Example 3

[0043] An adaptive engine exhaust temperature management and control method is proposed. During the engine bench development process, calibration work is completed under the normal operating mode of the engine according to the development goals, so that the emissions can meet the original engine emission engineering target requirements and achieve optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, they are denoted as EGTM1, EGTM2, and EGTM3, respectively. The temperature improvement effect of each exhaust temperature thermal management mode increases sequentially. Temperature limits are set for each exhaust temperature thermal management mode as the entry temperature and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry temperature and exit temperature of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0044] The temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine.

[0045] In addition, in this embodiment, there is an overlapping hysteresis interval between the temperature limit of the entry temperature of one exhaust temperature thermal management mode and the temperature limit of the exit temperature of the previous exhaust temperature thermal management mode, so as to avoid temperature fluctuations when switching temperature difference and continuous switching between two exhaust temperature thermal management modes.

[0046] In this embodiment, after the engine starts, the enable condition for the engine to enter the exhaust temperature thermal management mode is determined based on the predicted temperature of the SCR inlet. If the enable condition is not met, the engine continues to operate in normal mode until the condition is met, and then the exhaust temperature thermal management mode is determined and selected.

[0047] If the enabling conditions are met, the current predicted SCR inlet temperature is compared with the target SCR inlet temperature. Based on the temperature difference and the entry and exit temperatures of each exhaust temperature thermal management mode, the corresponding exhaust temperature thermal management mode is entered. For example, if the predicted SCR inlet temperature is lower than the exit temperature of EGTM1, then EGTM1 is entered; if the predicted SCR inlet temperature is lower than the exit temperature of EGTM2, then EGTM2 is entered.

[0048] In addition, when the predicted SCR inlet temperature rises, it is compared with the entry and exit temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the engine enters the next exhaust temperature thermal management mode until the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, at which point the engine enters normal mode.

[0049] Finally, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

[0050] Example 4

[0051] An adaptive engine exhaust temperature management and control method is proposed. During the engine bench development process, calibration work is completed under the normal operating mode of the engine according to the development goals, so that the emissions can meet the original engine emission engineering target requirements and achieve optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, they are denoted as EGTM1, EGTM2, and EGTM3, respectively. The temperature improvement effect of each exhaust temperature thermal management mode increases sequentially. Temperature limits are set for each exhaust temperature thermal management mode as the entry temperature and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry temperature and exit temperature of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0052] The temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine.

[0053] In addition, in this embodiment, there is an overlapping hysteresis interval between the temperature limit of the entry temperature of one exhaust temperature thermal management mode and the temperature limit of the exit temperature of the previous exhaust temperature thermal management mode, so as to avoid temperature fluctuations when switching temperature difference and continuous switching between two exhaust temperature thermal management modes.

[0054] In this embodiment, the switching of the engine's combustion control parameters is set with a time lag or slope limit to ensure smoothness between mode switching and avoid sudden combustion changes.

[0055] In this embodiment, after the engine starts, the enable condition for the engine to enter the exhaust temperature thermal management mode is determined based on the predicted temperature of the SCR inlet. If the enable condition is not met, the engine continues to operate in normal mode until the condition is met, and then the exhaust temperature thermal management mode is determined and selected.

[0056] If the enabling conditions are met, the current predicted SCR inlet temperature is compared with the target SCR inlet temperature. Based on the temperature difference and the entry and exit temperatures of each exhaust temperature thermal management mode, the corresponding exhaust temperature thermal management mode is entered. For example, if the predicted SCR inlet temperature is lower than the exit temperature of EGTM1, then EGTM1 is entered; if the predicted SCR inlet temperature is lower than the exit temperature of EGTM2, then EGTM2 is entered.

[0057] In addition, when the predicted SCR inlet temperature rises, it is compared with the entry and exit temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the engine enters the next exhaust temperature thermal management mode until the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, at which point the engine enters normal mode.

[0058] Finally, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

[0059] Example 5

[0060] An adaptive engine exhaust temperature management and control method is proposed. During the engine bench development process, calibration work is completed under the normal operating mode of the engine according to the development goals, so that the emissions can meet the original engine emission engineering target requirements and achieve optimal fuel consumption. Based on the exhaust temperature target of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets are developed. Using the average exhaust temperature set in the WHTC cycle as a benchmark, they are denoted as EGTM1, EGTM2, and EGTM3, respectively. The temperature improvement effect of each exhaust temperature thermal management mode increases sequentially. Temperature limits are set for each exhaust temperature thermal management mode as the entry temperature and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry temperature and exit temperature of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions.

[0061] The temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine.

[0062] In addition, in this embodiment, there is an overlapping hysteresis interval between the temperature limit of the entry temperature of one exhaust temperature thermal management mode and the temperature limit of the exit temperature of the previous exhaust temperature thermal management mode, so as to avoid temperature fluctuations when switching temperature difference and continuous switching between two exhaust temperature thermal management modes.

[0063] In this embodiment, the switching of the engine's combustion control parameters is set with a time lag or slope limit to ensure smoothness between mode switching and avoid sudden combustion changes.

[0064] In this embodiment, the predicted SCR inlet temperature is calculated based on the DOC inlet temperature, the specific heat capacity of DOC and DPF, and the heat loss of the SCR mixer.

[0065] In this embodiment, after the engine starts, the enable condition for the engine to enter the exhaust temperature thermal management mode is determined based on the predicted temperature of the SCR inlet. If the enable condition is not met, the engine continues to operate in normal mode until the condition is met, and then the exhaust temperature thermal management mode is determined and selected.

[0066] If the enabling conditions are met, the current predicted SCR inlet temperature is compared with the target SCR inlet temperature. Based on the temperature difference and the entry and exit temperatures of each exhaust temperature thermal management mode, the corresponding exhaust temperature thermal management mode is entered. For example, if the predicted SCR inlet temperature is lower than the exit temperature of EGTM1, then EGTM1 is entered; if the predicted SCR inlet temperature is lower than the exit temperature of EGTM2, then EGTM2 is entered.

[0067] In addition, when the predicted SCR inlet temperature rises, it is compared with the entry and exit temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the engine enters the next exhaust temperature thermal management mode until the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, at which point the engine enters normal mode.

[0068] Finally, when the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

[0069] This invention provides an adaptive engine exhaust temperature management control method that switches between different exhaust temperature thermal management modes based on the difference between the predicted and target values ​​of the SCR inlet temperature. This reduces fuel consumption while meeting exhaust temperature targets. Furthermore, it adjusts parameters according to ambient temperature and the target SCR inlet temperature, further reducing fuel consumption. After warming up to normal mode, if the exhaust temperature thermal management mode is reactivated, the use of multi-stage exhaust temperature thermal management modes effectively reduces the impact of engine parameter adjustments on driving experience, improving driving comfort.

[0070] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting it to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this invention is thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Furthermore, the technical solutions of this invention are defined only by the scope of the claims.

[0071] The aspects disclosed in this specification and claims are merely examples, and therefore, this specification and claims are not limited to the details shown. In the foregoing description, detailed descriptions of relevant known functions or configurations have been omitted where it would unnecessarily obscure the focus of this specification and claims.

[0072] When using the terms “comprising,” “having,” and “including” as described in this specification, there may be another part or other part unless used, and the terms used are generally singular but may also be plural.

[0073] Finally, it should be noted that the above description is a further detailed explanation of the invention in conjunction with specific embodiments. It should not be considered that the specific implementation of the invention is limited to these descriptions. For those skilled in the art, any simple substitutions made without departing from the concept of the invention should be considered within the scope of protection of this invention. The above embodiments are merely representative examples of the invention. Obviously, the invention is not limited to the above embodiments and many variations are possible. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the invention should be considered within the scope of protection of this invention.

[0074] It should be noted that the above description of the technical solutions is exemplary, and this specification may be embodied in different forms and should not be construed as limiting it to the technical solutions set forth herein. Rather, providing these descriptions will ensure that the disclosure of this invention is thorough and complete, and will fully convey the scope of this specification to those skilled in the art. Furthermore, the technical solutions of this invention are defined only by the scope of the claims. Features of various embodiments of this invention may be combined or spliced ​​together in part or in whole, and may be implemented in various different configurations as will be fully understood by those skilled in the art. Embodiments of this invention may be implemented independently of each other or may be implemented together in an interdependent relationship.

[0075] For those skilled in the art, several simple deductions or substitutions can be made without departing from the concept of the present invention, and the above structures should all be considered to fall within the protection scope of the present invention.

Claims

1. An adaptive engine exhaust temperature management and control method, characterized in that: During engine bench development, calibration work was completed under normal engine operating conditions according to development goals. This ensured that emissions met the original engine emission engineering targets while achieving optimal fuel consumption. Based on the target exhaust temperature of the WHTC cycle on the bench, several exhaust temperature thermal management modes with different exhaust temperature targets were developed. These modes were denoted as EGTM1, EGTM2, EGTM3, ... EGTM, using the average exhaust temperature set in the WHTC cycle as a benchmark. n The temperature enhancement effect of each exhaust temperature thermal management mode increases sequentially. A temperature limit is set for each exhaust temperature thermal management mode as the entry and exit temperature of that exhaust temperature thermal management mode. The predicted temperature of SCR inlet is compared with the entry and exit temperatures of each exhaust temperature thermal management mode to enable the engine to enter the exhaust temperature thermal management mode that meets the conditions. The temperature limit for each exhaust temperature thermal management mode is calibrated based on the actual test bench operation of the engine; There is an overlapping hysteresis interval between the temperature limit of the entry temperature of one exhaust temperature thermal management mode and the temperature limit of the exit temperature of the previous exhaust temperature thermal management mode; the switching settings of the engine combustion control parameters are subject to time delay or slope limit; the predicted SCR inlet temperature is calculated based on the DOC inlet temperature, the specific heat capacity of DOC and DPF, and the heat loss of the SCR mixer.

2. The adaptive engine exhaust temperature management and control method according to claim 1, characterized in that: After the engine starts, the engine enters the exhaust temperature thermal management mode based on the predicted temperature of the SCR inlet. If the conditions for entering the mode are not met, the engine continues to operate in normal mode until the conditions are met, at which point the exhaust temperature thermal management mode is determined and selected.

3. The adaptive engine exhaust temperature management and control method according to claim 2, characterized in that: If the enabling conditions are met, the system will match and enter the corresponding exhaust temperature thermal management mode based on the current predicted SCR inlet temperature and the entry and exit temperatures of each exhaust temperature thermal management mode.

4. The adaptive engine exhaust temperature management and control method according to claim 3, characterized in that: When the predicted SCR inlet temperature increases, it is compared with the inlet and outlet temperatures of the next exhaust temperature thermal management mode. If the requirements are met, the next exhaust temperature thermal management mode is entered.

5. The adaptive engine exhaust temperature management and control method according to claim 4, characterized in that: When the predicted SCR inlet temperature is higher than the exit temperature of the last exhaust temperature thermal management mode, the engine enters normal mode.

6. The adaptive engine exhaust temperature management and control method according to claim 5, characterized in that: When the engine is running in normal mode, if the predicted SCR inlet temperature is lower than the exit temperature of any exhaust temperature thermal management mode, the enable condition for re-entering the exhaust temperature thermal management mode will be determined.

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