CN114673584B

CN114673584B - Thermal management control method, device, equipment and medium for diesel engine aftertreatment system

Info

Publication number: CN114673584B
Application number: CN202210417693.9A
Authority: CN
Inventors: 赵德财; 孙善良; 殷治梅
Original assignee: Weichai Power Co Ltd
Current assignee: Weichai Power Co Ltd
Priority date: 2022-04-20
Filing date: 2022-04-20
Publication date: 2023-07-18
Anticipated expiration: 2042-04-20
Also published as: CN114673584A

Abstract

The application provides a thermal management control method device, equipment and medium of a diesel engine aftertreatment system. The method comprises the following steps: acquiring an overall risk coefficient of the current running condition of the diesel engine and a current transient condition state value; judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode or not according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition; if it is determined that the condition for entering the thermal management mode is satisfied, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value so that exhaust emission is performed at the set temperature value. The method effectively improves the response speed of the thermal management of the post-processing system.

Description

Thermal management control method, device, equipment and medium for diesel engine aftertreatment system

Technical Field

The present disclosure relates to diesel engine technologies, and in particular, to a method, an apparatus, a device, and a medium for controlling thermal management of a diesel engine aftertreatment system.

Background

Diesel engines are engines that burn diesel to obtain energy release, and with the continuous development of diesel engines, off-road four-stage diesel engines, such as diesel engines for loaders, diesel engines for excavators, and the like, have emerged. Off-road four-stage diesel engines typically include a controller for data acquisition, analysis, and corresponding control of the aftertreatment system, and an aftertreatment system. The aftertreatment system is used for eliminating main pollutants in tail gas emission when energy is supplied to clean diesel engine combustion oil. Aftertreatment systems typically include three components, a diesel oxidation catalyst (abbreviated as DOC), a diesel particulate filter (abbreviated as DPF), and a selective catalytic reduction (abbreviated as SCR).

At present, when the aftertreatment system works under the low-temperature exhaust working condition, the aftertreatment system is easy to generate crystallization carbon deposition, and when a vehicle uses high-sulfur inferior fuel, sulfur poisoning of a catalyst of the aftertreatment system is easy to cause, so that normal use of the vehicle is influenced. For these situations of the aftertreatment system, a trigger time interval is preset in the controller, and a designated temperature is pre-stored in the controller, and when the trigger time is determined to be reached, the controller controls to increase the exhaust temperature of the diesel engine according to the designated temperature, so that the aftertreatment system no longer works under the low exhaust temperature working condition.

However, in the conventional method, the exhaust temperature of the aftertreatment system is controlled based on the specified temperature, the actual operation condition is not fully considered, and the exhaust temperature of the aftertreatment system cannot be flexibly and reasonably thermally managed, so that the response speed of thermally managing the aftertreatment system is reduced to a certain extent.

Disclosure of Invention

The application provides a thermal management control method, a device, equipment and a medium of a diesel engine aftertreatment system, which are used for solving the problem that the response speed of thermal management of the aftertreatment system is reduced by controlling the exhaust temperature of the aftertreatment system based on a specified temperature in the prior art.

In a first aspect, the present invention provides a method for controlling thermal management of a diesel engine aftertreatment system, comprising:

acquiring an overall risk coefficient of the current running condition of the diesel engine and a current transient condition state value; judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode or not according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition; if it is determined that the condition for entering the thermal management mode is satisfied, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value so that exhaust emission is performed at the set temperature value.

In a second aspect, the present application provides a thermal management control apparatus for a diesel aftertreatment system, comprising:

the data acquisition module is used for acquiring the overall risk coefficient of the current operation condition of the diesel engine and the state value of the current transient condition;

the condition judging module is used for judging whether the diesel engine aftertreatment system meets the condition of entering the thermal management mode according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition;

and the temperature rise control module is used for controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value if the condition of entering the thermal management mode is determined to be met, so that the exhaust emission is carried out at the set temperature value.

In a third aspect, the present application provides an electronic device, comprising: a memory, a processor; the memory is used for storing the processor executable instructions; the processor is configured to execute a computer program or instructions to implement the thermal management control method of the diesel aftertreatment system of the first aspect.

In a fourth aspect, the present application provides a computer-readable storage medium having stored therein computer-executable instructions that, when executed by a processor, are configured to implement the thermal management control method of the diesel aftertreatment system of the first aspect.

According to the thermal management control method device, the thermal management control equipment and the thermal management control medium for the diesel engine aftertreatment system, the overall risk coefficient of the current operation working condition of the diesel engine is obtained, and the current transient working condition state value of the diesel engine aftertreatment system is obtained; judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode or not according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition; if it is determined that the condition for entering the thermal management mode is satisfied, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value so that exhaust emission is performed at the set temperature value. At least one of the overall risk coefficient of the current running condition and the current transient condition state value can directly reflect the working condition of the current diesel engine. Therefore, whether the diesel engine aftertreatment system meets the condition of entering the thermal management is judged according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition, and the condition of entering the thermal management mode is determined to be flexible and reasonable by fully considering the actual working condition of the aftertreatment system, so that the exhaust temperature of the aftertreatment system can be flexibly and reasonably thermally managed, the temperature rise of the inlet exhaust temperature of the particulate filter can be completed without waiting for the time interval of triggering the temperature rise, the response speed of thermally managing the aftertreatment system is effectively improved, and the treatment efficiency of the aftertreatment system is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure.

FIG. 1 is an application scenario diagram of a thermal management control method of a diesel aftertreatment system in which embodiments of the present application may be implemented;

FIG. 2 is a flow chart of a thermal management control method of a diesel aftertreatment system according to an embodiment of the present disclosure;

FIG. 3 is a flow chart of a thermal management control method of a diesel aftertreatment system according to another embodiment of the present disclosure;

FIG. 4 is a schematic illustration of a thermal management control device of a diesel aftertreatment system according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of an electronic device used in implementing thermal management control of a diesel aftertreatment system in accordance with an embodiment of the present application.

Specific embodiments of the present disclosure have been shown by way of the above drawings and will be described in more detail below. These drawings and the written description are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the disclosed concepts to those skilled in the art by reference to specific embodiments.

Detailed Description

Reference will now be made in detail to exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, the same numbers in different drawings refer to the same or similar elements, unless otherwise indicated. The implementations described in the following exemplary examples are not representative of all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as detailed in the accompanying claims.

The terms referred to in this application are explained first:

the diesel engine comprises a controller and an after-treatment system, wherein the controller is used for data acquisition, analysis and corresponding control of the after-treatment system. The aftertreatment system is used for eliminating main pollutants in tail gas emission when energy is supplied to clean diesel engine combustion oil. Aftertreatment systems typically include three components, a diesel oxidation catalyst (abbreviated as DOC), a diesel particulate filter (abbreviated as DPF), and a selective catalytic reduction (abbreviated as SCR).

Oxidation catalyst: with oxidation catalyst, mainly eliminating CO and HC in tail gas, and oxidizing NO to NO ₂ 。

Diesel particulate filter: the method is mainly used for filtering the particulate matters in the tail gas in a passive regeneration mode.

Selecting a catalytic reducer: the method is mainly used for eliminating nitrogen oxides in the tail gas.

Thermal management mode: the working mode of the exhaust temperature of the diesel engine is improved through means of a choke inlet throttle valve, a choke exhaust throttle valve, in-cylinder post-injection and the like.

The tail gas purifying and discharging process comprises the following steps: the process of oxidation catalysis is carried out by the oxidation catalyst, the particulate matters are filtered by the particulate filter, and finally the process of eliminating nitrogen oxides in the tail gas by the selective catalytic reducer is carried out.

For a clear understanding of the technical solutions of the present application, the prior art solutions will be described in detail first.

When the aftertreatment system works under the low exhaust temperature working condition, the passive regeneration of the DPF is weakened, and NO can not be efficiently made ₂ And soot to perform oxidation reaction to eliminate carbon deposition of the DPF, thereby causing the DPF to be easy to carbon deposition; SCR is easily crystallized; sulfur poisoning of the aftertreatment catalyst can result when the vehicle is using poor quality high sulfur fuel.

At present, the diesel engine aftertreatment system aims to solve the problems of sulfur poisoning of a catalyst, easy carbon deposition crystallization and the like. In general, a trigger time interval is preset in the controller and a designated temperature is pre-stored in the controller, and when the trigger time is determined to be reached, the controller controls to increase the exhaust temperature of the diesel engine according to the designated temperature, so that the aftertreatment system does not work under the low exhaust temperature working condition any more. This method controls the exhaust temperature of the aftertreatment system mainly based on the specified temperature, and when the temperature of the aftertreatment system itself or the ambient temperature becomes low, there is a possibility that the temperature is not raised in time. I.e. the temperature needs to rise but not within the time that triggers the temperature rise, resulting in an inability to rise. Therefore, the actual operation condition is not fully considered in the prior art, and the exhaust temperature of the aftertreatment system cannot be flexibly and reasonably thermally managed, so that the response speed of thermally managing the aftertreatment system is reduced to a certain extent.

Therefore, when the technical problems in the prior art are faced, the inventor finds out through creative research that, in order to realize flexible and reasonable thermal management of the exhaust temperature of the aftertreatment system, whether the condition of entering the thermal management mode is met or not is judged according to the working condition of the current diesel engine, and the inlet exhaust temperature of the particle filter of the diesel engine is controlled to rise to a set temperature value under any condition of meeting the condition of entering the thermal management mode. The working condition of the current diesel engine can be at least one of the overall risk coefficient of the current running condition and the state value of the current transient condition, and because the entering of the thermal management mode is determined based on the actual working condition of the current diesel engine, the condition of entering the thermal management mode is judged based on the condition, the exhaust temperature of the aftertreatment system can be flexibly and reasonably thermally managed, the temperature rise of the inlet exhaust temperature of the particulate filter can be completed without waiting for the time interval of triggering the temperature rise, and the response speed of the thermal management of the aftertreatment system is effectively improved.

The inventor proposes the technical scheme of the embodiment of the invention based on the creative discovery. The network architecture and application scenario of the thermal management control method of the diesel engine aftertreatment system provided by the embodiment of the invention are described below.

As shown in fig. 1, an application scenario of a thermal management control method of a diesel engine aftertreatment system provided in an embodiment of the present application includes an aftertreatment system 1, a controller 2 and a diesel engine 3 in a network architecture corresponding to the application scenario, where the aftertreatment system 1 specifically includes an oxidation catalyst 11, a particulate filter 12 and a selective catalytic reducer 13. The controller 2 is respectively in communication connection with the aftertreatment system 1 and the diesel engine 3, the controller 2 can acquire the current operation condition of the diesel engine, judge whether the aftertreatment system of the diesel engine meets the condition of entering the thermal management mode according to the current operation condition, and control the inlet exhaust temperature of the particulate filter 12 of the aftertreatment system 1 to rise to a set temperature value when the aftertreatment system 1 is determined to meet the condition of entering the thermal management mode based on the current operation condition.

The specific application scenario of this application, at vehicle operation in-process, can constantly discharge tail gas, in order to make diesel engine aftertreatment system fully reduce carbon deposition crystallization and prevent catalyst sulfur poisoning, need the controller to control the diesel engine and avoid appearing low exhaust temperature operating mode, in time the intensification reaches the settlement temperature value. The controller obtains the overall risk coefficient of the current running condition of the diesel engine and the state value of the current transient condition. And judging whether the diesel engine aftertreatment system meets the condition of entering the thermal management mode according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition. And if the condition of entering the thermal management mode is determined to be met, sending a heating instruction to the diesel engine aftertreatment system, and controlling the inlet exhaust temperature of the particulate filter of the diesel engine to be heated to a set temperature value so as to enable exhaust emission to be carried out at the set temperature value.

The following describes the technical solutions of the present application and how the technical solutions of the present application solve the above technical problems in detail with specific embodiments. The following embodiments may be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments. Embodiments of the present application will be described below with reference to the accompanying drawings.

Fig. 2 is a schematic diagram of a thermal management control method of a diesel engine aftertreatment system according to an embodiment of the present application, and as shown in fig. 2, an execution subject of the thermal management control method of a diesel engine aftertreatment system according to the embodiment is a controller of a diesel engine, where the controller of the diesel engine may be disposed on an electronic device. The thermal management control method of the diesel engine aftertreatment system provided in the embodiment includes the following steps:

step 101, acquiring an overall risk coefficient of the current operation condition of the diesel engine, and.

The operating condition refers to the working condition of the diesel engine in the process of supplying energy for the operation of the vehicle. The current operating condition refers to the current operating condition of the diesel engine. The risk factor represents the risk of carbon deposition and crystallization in the diesel aftertreatment system, and the probability of carbon deposition and crystallization in the diesel aftertreatment system can be used. The overall risk coefficient is a risk coefficient obtained by considering the whole process of the current operation condition, and can reflect the probability of carbon deposition and crystallization of the diesel engine aftertreatment system under the current operation condition most.

The transient state value represents a value corresponding to the transient working condition of the diesel engine in the working process. Transient operating condition state values may include intensity values and non-intensity values. For example, the intensity value may be 1, the non-intensity value may be 0, and if it is determined that the diesel engine is intense in the working process, the transient state value is set to 1 correspondingly; if the diesel engine is not severe in the working process, the corresponding transient working condition state value is set to 0. Here, specific values of the intensity level value and the non-intensity level value are not limited. The current transient working condition state value is a transient working condition state value obtained by integrating the whole process of the current operation working condition and can most reflect whether the current diesel engine is severe in the working process.

The mode of acquiring the overall risk coefficient of the current operation working condition and the current transient working condition state value can be acquired through a data acquisition module integrally arranged on a controller of the diesel engine, the data acquisition module respectively acquires the operation power and the rotation speed of the diesel engine in real time through a power sensor and a speed sensor, and the controller can calculate and determine the torque according to the acquired operation power and rotation speed of the diesel engine. The external data acquisition equipment can acquire the running power and the rotating speed of the diesel engine from the power sensor and the speed sensor in real time, and then the controller of the diesel engine is acquired through the external data acquisition equipment.

Step 102, judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition.

The operating condition and transient operating condition state values of the diesel engine directly reflect the operating condition of the diesel engine, and the operating condition of the diesel engine is closely related to carbon deposition and crystallization of a diesel engine aftertreatment system. Specifically, the greater the overall risk coefficient of the operating condition of the diesel engine, or when the diesel engine is determined to be severe in the working process according to the transient operating condition state value, the more easily the aftertreatment system is subjected to carbon deposition, crystallization and sulfide elimination. Therefore, at least one of the overall risk coefficient of the current operating condition and the current transient operating condition state value is set as a condition for judging that the diesel engine aftertreatment system enters the thermal management mode. If at least one of the overall risk coefficient and the current transient working condition state can meet the condition of entering the thermal management mode, the controller of the diesel engine controls the entering of the thermal management mode to carry out thermal management on the post-treatment system of the diesel engine.

If it is determined that the condition for entering the thermal management mode is satisfied, the inlet exhaust temperature of the particulate filter of the diesel engine is controlled to rise to a set temperature value so that exhaust emission is performed at the set temperature value.

Specifically, if it is determined that the condition for entering the thermal management mode is satisfied, the controller controls the inlet exhaust temperature of the particulate filter to rise to a set temperature value so that exhaust gas discharge can be performed at the set temperature value. The current operating condition may be understood as a low exhaust temperature condition, corresponding to the initial temperature. Since the set temperature value is a temperature value obtained after the initial temperature is raised, after the temperature is raised, a higher temperature condition than the low temperature discharge condition. Therefore, the exhaust emission is carried out at the set temperature, and the low-temperature exhaust working condition is avoided, so that sulfide can be more fully eliminated, and carbon deposition and crystallization can be reduced.

The heating to the set temperature may be performed intermittently or gradually according to a linear law, which is not limited in this embodiment.

According to the thermal management control method of the diesel engine aftertreatment system, the overall risk coefficient of the current operation working condition of the diesel engine is obtained, and the current transient working condition state value of the diesel engine aftertreatment system is obtained; judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode or not according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition; if it is determined that the condition for entering the thermal management mode is satisfied, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value so that exhaust emission is performed at the set temperature value. At least one of the overall risk coefficient of the current running condition and the current transient condition state value can directly reflect the working condition of the current diesel engine. Therefore, whether the diesel engine aftertreatment system meets the condition of entering the thermal management is judged according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition, and the condition of entering the thermal management mode is determined to be flexible and reasonable by fully considering the actual working condition of the aftertreatment system, so that the exhaust temperature of the aftertreatment system can be flexibly and reasonably thermally managed, the temperature rise of the inlet exhaust temperature of the particulate filter can be completed without waiting for the time interval of triggering the temperature rise, the response speed of thermally managing the aftertreatment system is effectively improved, and the treatment efficiency of the aftertreatment system is improved.

As an alternative implementation manner, in this embodiment, step 103 includes the following steps:

step 103a, comparing the overall risk coefficient of the current operation condition with a first risk coefficient threshold value, and judging whether the current operation condition is a high risk condition according to a comparison result.

The first risk coefficient threshold is a threshold used for distinguishing whether the operation working condition corresponding to the overall risk coefficient is a high risk working condition or not, and is preset and stored in the controller. Optionally, comparing the overall risk coefficient of the current operation condition with a first risk coefficient threshold, and if the overall risk coefficient is greater than the first risk coefficient threshold, determining that the current operation condition is a high risk condition; and if the overall risk coefficient is smaller than or equal to the first risk coefficient threshold value, determining that the current operation working condition is not a high risk working condition.

Step 103b, judging whether the transient variation of the current operation working condition of the diesel engine aftertreatment system reaches a preset state according to the current transient working condition state value.

Wherein, the transient change refers to the transient change condition of the running working condition of the diesel engine in the working process. The operation condition is divided according to transient change into at least two states of intense state and mild state. The preset state may be a severe state, and the transient variation value corresponding to the severe state may be preset and stored in the controller. For example, the transient change value corresponding to the severe state is 1. Then 1 is stored in the controller.

Specifically, a current transient state value is obtained, the current transient state value is compared with a transient change value corresponding to a severe state, and if the current transient state value is consistent with the transient change value corresponding to the severe state, the transient change of the current operation working condition is determined to reach a preset state. If the current transient state value is inconsistent with the transient change value corresponding to the severe state, determining that the transient change of the current operation working condition does not reach the preset state.

The preset state is a severe state, the transient variation value corresponding to the severe state is 1, and the transient variation value corresponding to the mild state is 0. And if the current instantaneous working condition state value is 1, determining that the instantaneous change of the current operation working condition reaches a preset state. If the current instantaneous working condition state value is 0, determining that the instantaneous change of the current operation working condition does not reach the preset state.

Step 103c, if it is determined that the current operation condition is a high risk condition and/or the transient variation of the current operation condition reaches a preset state, determining that the diesel engine aftertreatment system meets the condition of entering the thermal management mode.

Specifically, the current operating condition of the diesel engine is a high-risk condition, and/or the transient change of the current operating condition reaches a preset state, which indicates that the aftertreatment system is more prone to carbon deposition, crystallization and sulfide elimination. Therefore, the current operation condition is set to be at least one of a high risk condition and a transient change of the current operation condition reaching a preset state, and the set condition is used as a condition for judging that the diesel engine aftertreatment system enters the thermal management mode.

Step 103d, if it is determined that the current operation condition is not a high risk condition and the transient variation of the current operation condition does not reach the preset state, determining that the diesel engine aftertreatment system does not meet the condition of entering the thermal management mode.

Specifically, the current operation condition of the diesel engine is not a high-risk condition, and the transient change of the current operation condition does not reach a preset state, which indicates that the aftertreatment system is not easy to deposit carbon, crystallize and eliminate sulfide at the moment. Therefore, under the conditions that the current operation working condition is not a high-risk working condition and the transient change of the current operation working condition does not reach the preset state and is met at the same time, the condition that the diesel engine aftertreatment system enters the thermal management mode is determined not to be met.

According to the thermal management control method for the diesel engine aftertreatment system, the overall risk coefficient of the current operation working condition is compared with the first risk coefficient threshold value, so that whether the current operation working condition is a high risk working condition or not is judged. And judging whether the transient variation of the current operation working condition reaches a preset state or not according to the current transient working condition state value. Since the aftertreatment system is prone to carbon deposition, crystallization and difficult to eliminate sulfides when high risk conditions and/or transient changes reach a preset state; when the working condition is not high and the transient change does not reach the preset state, carbon deposition, crystallization and sulfide elimination are difficult. Accordingly, upon determining that the high risk operating condition and/or the transient variation reaches the preset state, it is determined that the diesel aftertreatment system satisfies the condition to enter the thermal management mode. And when the high risk work condition is not determined and the transient change does not reach the preset state, determining that the diesel engine aftertreatment system does not meet the condition of entering the thermal management mode. Based on the setting, the post-treatment system of the diesel engine can be actively and accurately subjected to heat management in time according to the actual operation condition, so that the exhaust emission temperature of the post-treatment system of the diesel engine is improved, carbon deposition, crystallization and sulfide elimination are reduced as much as possible.

In this embodiment, the step 101 of obtaining the overall risk coefficient of the current operating condition of the diesel engine includes the following steps:

step 1011, obtaining the operation parameters of the diesel engine at each moment in the current preset time length, so as to obtain the operation conditions of the aftertreatment system of the diesel engine at each moment in the current preset time length, wherein the operation conditions are represented by the operation parameters at the corresponding moment.

The preset duration is a duration formed by preset time intervals and is stored in the controller. The current preset duration refers to a duration for obtaining the current operation condition. The operation condition can be represented by operation parameters, wherein the operation parameters comprise rotating speed and torque, and a controller acquires the operation parameters in the whole operation process in real time in the operation process of the diesel engine. The operation conditions of the diesel engine aftertreatment system at each moment in the current preset time can be obtained by acquiring the operation parameters of the diesel engine at each moment in the current preset time.

Step 1012, determining moment risk coefficients corresponding to the operation working conditions at each moment respectively based on the operation working conditions at each moment and a pre-stored working condition risk mapping table.

The controller also stores a working condition risk mapping table in advance, and the working condition risk mapping table stores a corresponding relation between the operation working condition and the risk coefficient. In one embodiment, the operating condition risk map is as shown in Table 1:

TABLE 1

For example, when the rotational speed is 700rpm and the torque is 100n.m, the risk factor having the map relationship is 1.5.

The risk coefficient comprises an overall risk coefficient and a moment risk coefficient, wherein the moment risk coefficient refers to a risk coefficient corresponding to an operation condition of the diesel engine at a certain moment. The current operation condition is obtained based on the operation condition of the diesel engine at each moment in the current preset time, and the overall risk coefficient is obtained based on the moment risk coefficient at each moment. In order to reasonably obtain the overall risk coefficient based on the moment risk coefficient of each moment, after the operation working condition of the diesel engine at each moment is obtained, the corresponding risk coefficient is queried based on the working condition risk mapping table, and the moment risk coefficient corresponding to the operation working condition at each moment is determined.

Step 1013, determining an overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the moment risk coefficient and the frequency occupation ratio in the current preset time.

Specifically, the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system is closely related to the magnitude of the risk coefficient at each moment and the frequency of occurrence duty ratio in the current preset duration. Therefore, when the overall risk coefficient is determined, the frequency occupation ratio of the time risk coefficient in the current preset time period is determined according to the size of the time risk coefficient.

According to the thermal management control method for the diesel engine aftertreatment system, the operation parameters of the diesel engine at all times in the current preset time period are obtained to obtain the operation conditions of the diesel engine aftertreatment system at all times in the current preset time period, and the operation conditions are represented by the operation parameters at the corresponding times; based on the operation working conditions at each moment and a pre-stored working condition risk mapping table, respectively determining moment risk coefficients corresponding to the operation working conditions at each moment; and determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the moment risk coefficient and the occurrence frequency duty ratio in the current preset time period, wherein the overall risk coefficient is determined based on the magnitude of the risk coefficient at each moment and the occurrence frequency duty ratio, so that the accuracy of taking the overall risk coefficient as the most representative risk coefficient of the current operation condition is ensured.

As an alternative implementation, in this embodiment, step 1013 includes the following steps:

in step 1013a, if the moment risk factor is greater than the first risk factor threshold, the moment risk factor is determined as the target risk factor.

Wherein the target risk factor is a moment risk factor that is more closely related to the determination of the overall risk factor. When the overall risk coefficient is determined, only the target risk coefficient is considered, and the risk coefficient at other moments is not considered, so that the accuracy of the overall risk coefficient can be ensured, and the calculation processing amount of the controller can be reduced. Specifically, for risk coefficients at each moment in the current preset duration, if the risk coefficient at the moment is greater than a first risk coefficient threshold, determining the risk coefficient at the moment as a target risk coefficient. For example, the first risk factor threshold may be set to 1, and as can be seen from table 1, risk factors greater than 1 include 1.2 and 1.5, so that the risk factors at the time points of 1.2 and 1.5 in the current preset duration may be determined as target risk factors.

Step 1013b, determining an overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the frequency of occurrence of the target risk coefficient within the current preset time period.

Specifically, after the target risk coefficient is determined, the overall risk coefficient needs to further consider the frequency of occurrence of the target risk coefficient within the current preset duration. Because the target risk factor can be determined based on the frequency of occurrence duty cycle for calculating the importance of the overall risk factor. In general, the higher the frequency of occurrence of a target risk factor, the more important that the target risk factor is in calculating the overall risk factor. The more accurate the overall risk coefficient calculated from the target risk coefficient.

In the thermal management control method for a diesel engine aftertreatment system provided by the embodiment, if the moment risk coefficient is greater than the first risk coefficient threshold value, determining the moment risk coefficient as a target risk coefficient; and determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the frequency occupation ratio of the target risk coefficient in the current preset time. The target risk coefficient is obtained by screening the risk coefficient at each moment, and then the overall risk coefficient is determined according to the occurrence frequency proportion of the target risk coefficient in the current preset duration.

As an alternative implementation, in this embodiment, step 1013b includes the following steps:

step 1014 obtains the number of target risk coefficients.

Specifically, in the current preset duration, more than one target risk coefficient may occur based on the risk coefficient of each moment obtained by the current operation condition. Thus, in order to determine the overall risk coefficient based on the appropriate target risk coefficient, the controller also determines the number of target risk coefficients after determining the target risk coefficient.

In step 1015, if the number of the target risk coefficients is one, and the frequency of occurrence duty ratio of the target risk coefficients in the current preset duration is greater than the first duty ratio threshold, the target risk coefficients are determined as the overall risk coefficients of the current operation condition.

The controller also stores a risk ratio threshold value table in advance, wherein the risk ratio threshold value table comprises corresponding relations between risk coefficients and ratio threshold values, and the corresponding ratio threshold values are arranged for all the risk coefficients. The duty cycle threshold here includes a first duty cycle threshold and a second duty cycle threshold, which are substantially identical and differ only by name. If only one target risk coefficient exists, and the occurrence frequency duty ratio of the target risk coefficient in the current preset duration is larger than a first duty ratio threshold value, determining the target risk coefficient as an overall risk coefficient of the current operation condition. For example, only one target risk coefficient of 1.2 is provided, the corresponding first duty ratio threshold value of the target risk coefficient 1.2 in the risk duty ratio threshold value table is 40%, and if the occurrence frequency duty ratio of the target risk coefficient of 1.2 is greater than 40% in the current preset duration, the target risk coefficient is determined to be the overall risk coefficient of the current operation condition.

In step 1016, if the number of the target risk coefficients is at least two, a second duty ratio threshold corresponding to each target risk coefficient is determined, where the second duty ratio threshold is inversely related to the size of the target risk coefficient.

And if the target risk coefficients are at least two, respectively determining second duty ratio thresholds corresponding to the target risk coefficients. In the risk duty cycle threshold table, the duty cycle threshold is inversely related to the risk factor. Similarly, the second duty cycle threshold is inversely related to the target risk factor size. The duty ratio threshold is set to be inversely related to the risk coefficient, because the greater the risk coefficient is, the closer the operation condition is to the high risk condition, or the higher the high risk degree of the high risk condition is, so that under the condition that the high risk condition degree is the same, the greater risk coefficient can correspond to the smaller duty ratio threshold compared with other smaller risk coefficients.

Step 1017, if any target risk coefficient exists and the frequency of occurrence of the target risk coefficient within the current preset duration is greater than the corresponding second duty threshold, determining the target risk coefficient as the overall risk coefficient of the current operation condition.

Specifically, under the condition that the target risk coefficients are at least two, if any one of the target risk coefficients is larger than the corresponding second duty ratio threshold value in the current preset duration, the target risk coefficient is determined to be the overall risk coefficient of the current operation condition. That is, as long as any one of the target risk coefficients satisfies that the occurrence frequency ratio thereof is greater than the corresponding second duty ratio threshold value, it may be regarded as the overall risk coefficient.

According to the thermal management control method of the diesel engine aftertreatment system, the number of the target risk coefficients is obtained; if the number of the target risk coefficients is one, and the occurrence frequency duty ratio of the target risk coefficients in the current preset duration is larger than a first duty ratio threshold value, determining the target risk coefficients as the overall risk coefficients of the current operation working condition. And if the number of the target risk coefficients is at least two, respectively determining a second duty ratio threshold corresponding to each target risk coefficient, wherein the second duty ratio threshold is inversely related to the size of the target risk coefficient. Because the situation that one or more target risk coefficients exist is considered at the same time, the mode of determining the overall risk coefficient is adjusted according to different situations, and therefore accuracy of calculating the overall risk coefficient is improved.

In this embodiment, the obtaining, in step 101, the current transient state value of the post-treatment system of the diesel engine includes: the transient change characteristics of the diesel engine are obtained, and the current transient state condition state value is determined based on the transient change characteristics.

Wherein, the transient change characteristic refers to the parameter characteristic of the transient change in the running process of the diesel engine. The controller can acquire transient change characteristics of the diesel engine from the power sensor and the speed sensor in real time through the data acquisition module or external data acquisition equipment, and determine a current transient state condition state value based on the transient change characteristics in a period of time.

As an optional implementation manner, in this embodiment, obtaining a transient variation characteristic of the diesel engine and determining a current transient condition state value based on the transient variation characteristic includes the following steps:

step 201, acquiring driving behavior data of a diesel engine and determining driving rough degree.

The driving behavior data refer to behavior data related to vehicle driving in the running process of the diesel engine. The driving behavior data may be used to represent transient changes in the operating conditions of the diesel engine. The cruising degree refers to the cruising degree of the vehicle during the running process of the diesel engine. When other factors are the same, the greater the driving rough degree is, which indicates the more severe the transient change of the operation condition.

Step 202, obtaining the torque change rate of the diesel engine in a preset time window.

The preset time window is a window in a duration corresponding to a preset time interval, and the torque of the diesel engine is collected in the preset time window, and the torque change rate is calculated. The torque change rate refers to a change rate of torque in a period of time. The greater the rate of torque change, the more severe the transient change in operating conditions is indicated, given the cruising power and other factors.

Step 203, determining a current transient state condition value according to the driving rough degree and the torque change rate; the transient change characteristics of the diesel engine comprise the driving rough degree and the torque change rate.

The driving rough degree and the torque change rate are important factors reflecting the instantaneous operation condition, so that when the current transient operation condition state value is determined, the determination can be performed according to the driving rough degree and the torque change rate. If the driving rough degree is larger than the rough degree threshold value and the torque change rate is larger than the change threshold value, determining to set the current transient state value as the transient change corresponding to the intensity degreeThe values are consistent. And if the driving rough degree is not greater than the rough degree threshold value and the torque change rate is not greater than the change threshold value, determining to set the current transient working condition state value to be consistent with the transient change value corresponding to the non-intensity degree. Wherein the value of the rough threshold value can be 10%2/s, namely the change rate of the accelerator opening per second is 10% ² . The change threshold may be 50%, and the value is not particularly limited here.

As an alternative implementation manner, in this embodiment, step 201 includes the following steps:

and 2011, acquiring the throttle opening and the throttle acceleration of the diesel engine.

The driving behavior data comprise the accelerator opening degree and the accelerator acceleration of the diesel engine. In order to calculate the cruising power, the controller obtains the accelerator opening and the accelerator acceleration of the diesel engine.

Step 2012, determining the cruising power according to the accelerator opening and the accelerator acceleration.

Wherein, there is a relation between the driving behavior data and the driving rough degree, and the relation is stored in the controller. The relation is specifically: drive_st1=2×pxa_p. Where drive_st1 is the cruising power, p is the accelerator opening, a_p is the accelerator acceleration, a_p= (p_t2-p_t1)/(t 2-t 1), p_t2 is the accelerator opening at time t2, and p_t1 is the accelerator opening at time t 1.

According to the thermal management control method for the diesel engine aftertreatment system, the accelerator opening and the accelerator acceleration of the diesel engine are obtained, and the driving rough degree is calculated according to the accelerator opening and the accelerator acceleration. Because the cruising intensity is mainly related to the accelerator opening and the accelerator acceleration, the cruising intensity obtained based on the accelerator opening and the accelerator acceleration can accurately reflect the cruising intensity of the vehicle in the running process of the diesel engine.

As an alternative implementation manner, in this embodiment, step 202 includes the following steps:

in step 2021, in a preset time window, the torques of the diesel engine at each moment are calculated respectively, and the torque difference value corresponding to each two adjacent moments is calculated.

Wherein the torque is The difference is t _i Torque in seconds and t _i-1 The difference between the torques in seconds, i.e. the torque difference corresponding to the two adjacent moments.

In a preset time window, a plurality of moments are provided, the torque of the diesel engine at each moment is obtained, and the torque difference value corresponding to every two adjacent moments is calculated.

Step 2022, determining, based on each torque difference, a transient change degree of the operating condition corresponding to each two adjacent moments.

The torque difference values are arranged in time sequence, and the transient change degree of the operation working condition corresponding to each two adjacent moments can be determined.

In step 2023, the ratio of the moment corresponding to the severe transient change degree of the operating condition to all the moments in the whole preset time window is calculated.

If the torque difference value falls within the preset difference value range, determining that the transient change degree of the operation working condition is not severe, and the operation working condition is unstable; if the torque difference value does not fall within the preset difference value range, determining that the transient change degree of the operation working condition is severe and the operation working condition is in a transient state. The preset difference value range may be-50 n.m to 50n.m, where the numerical value is not particularly limited, and the upper limit value may be generally larger.

The controller calculates the ratio of all times in the whole preset time window when the transient change degree of the operation working condition is violently corresponding.

In step 2024, the ratio is determined as the torque rate of the diesel engine.

Specifically, when the above ratio is obtained, the ratio may be determined as the torque change rate of the diesel engine.

According to the thermal management control method of the diesel engine aftertreatment system, torque of the diesel engine at each moment is calculated respectively in a preset time window, and torque difference values corresponding to every two adjacent moments are calculated; determining the transient change degree of the operation working condition corresponding to each two adjacent moments based on the torque difference values; calculating the ratio of the moment corresponding to the severe transient change degree of the operation working condition to all moments in the whole preset time window; the ratio is determined as a torque rate of change of the diesel engine. The torque change rate is determined based on the ratio of the moment corresponding to the severe transient change degree of the operating condition to all the moments in the whole preset time window, so that the accuracy of calculating the torque change rate is improved.

As an optional implementation manner, in this embodiment, on the basis of any one of the foregoing embodiments, after step 104, the following steps are further included:

step 105, correcting the preset time based on the temperature distribution of the inlet exhaust gas temperature of the particulate filter of the diesel engine and the current ambient temperature to obtain the regeneration duration.

The oxidation catalyst of the diesel engine is connected with the particle filter through a pipeline, a cavity is formed in the joint between the particle filter and the pipeline, and a first temperature sensor is installed in the cavity and can be used for collecting the temperature of gas flowing through the pipeline. Typically, the gas temperature of the conduit is close to the gas temperature within the particulate filter. The gas temperature acquired by the first temperature sensor in real time is transmitted to the controller and stored in the controller. The temperature profile refers to the gas temperature of the particle sensor over a period of time.

A second temperature sensor is mounted in the appropriate position of the vehicle and can be used to collect a temperature value of the external environment, typically the air temperature. The current ambient temperature is the current ambient air temperature. When the operation condition of the vehicle is changed to a mild state in a transient manner, the vehicle is understood to not perform a high-intensity task or perform no task currently, and the diesel engine is not required to provide more energy. In this case, the exhaust temperature of the diesel engine is lower than when performing a high-intensity task or a task, and is regarded as a low exhaust temperature condition.

Wherein the preset duration is a constant temperature duration in which the set inlet exhaust temperature of the particulate filter is maintained at the set temperature value. Alternatively, the set temperature value may be set to 480 ℃, and the preset time period may be 20min, and the set temperature value and the preset time period are not particularly limited herein.

Since the inlet exhaust gas temperature of a diesel particulate filter is mainly affected by the temperature distribution and the current ambient temperature. Accordingly, the preset time period is corrected based on the temperature distribution and the current ambient temperature to obtain the regeneration time period.

Step 106, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to maintain the set temperature value for the regeneration period.

Specifically, because the regeneration time length is obtained by correcting the preset time length based on the temperature distribution and the current environmental temperature, the inlet exhaust temperature of the particulate filter of the diesel engine is controlled to keep a set temperature value to reach the regeneration time length, and the regeneration time length is longer than the preset time length under the low exhaust temperature working condition, so that the time length of keeping the inlet exhaust temperature of the particulate filter to keep the set temperature value can be prolonged, carbon deposition crystallization is reduced as much as possible, and catalyst sulfur poisoning is prevented; under the high exhaust temperature working condition, the regeneration time is shorter than the preset time, and the time for keeping the inlet exhaust temperature of the particulate filter at the set temperature value can be shortened, so that the maintenance and the operation of the diesel engine are facilitated.

According to the thermal management control method for the diesel engine aftertreatment system, the regeneration duration is obtained by correcting the preset time based on the temperature distribution of the inlet exhaust temperature of the particulate filter and the current environment temperature, and the particulate filter is controlled to keep the set temperature value for the regeneration duration. The constant temperature duration of the set temperature value is adjusted by considering the actual temperature change condition of the particle filter, so that the reduction of carbon deposition crystallization and the prevention of sulfur poisoning of the catalyst are facilitated.

As an alternative implementation, in this embodiment, step 105 includes the following steps:

in step 1051, if it is determined that the average temperature of the particulate filter of the diesel engine has a duty cycle in the temperature profile greater than a third duty cycle threshold within the current predetermined time period, a first correction factor is determined.

The average temperature of the particulate filter may be an average value of temperatures within a current preset time period, or may be at least one temperature with the largest occurrence number of temperatures within the current preset time period. As previously mentioned, the temperature profile is the gas temperature of the particle sensor over a period of time. The temperature distribution refers to all gas temperature values within the current preset time period. If the duty ratio of the average temperature in the temperature distribution within the current preset time period is larger than the third duty ratio threshold value, the first correction coefficient can be determined according to the average temperature and the stored first correction coefficient table. The first correction coefficient table is shown in table 2:

TABLE 2

Average temperature (. Degree. C.)	250 or less	250-300	300-350	350-400	400 or more
						First correction coefficient	1.3	1.1	0.5	0.3	0

For example, the average temperature of the particulate filter is 310 ℃, with a corresponding first correction factor of 0.5.

If it is determined that the duty cycle of the current ambient temperature in the collection temperature set is greater than the fourth duty cycle threshold, a second correction factor is determined, step 1052.

The temperature collection is all temperature values of the external environment collected by the second temperature sensor within the current preset time. If the duty ratio of the current ambient temperature in the collection temperature set is determined to be larger than the fourth duty ratio threshold value, a second correction coefficient can be determined according to the current ambient temperature and the second correction coefficient table. The second correction coefficient table is shown in table 3:

TABLE 3 Table 3

Current ambient temperature (DEG C)	-10-0	0-10	10-20	30 or more
					Second correction coefficient	1.2	1.1	1	0

For example, the current ambient temperature is 8 ℃, and the second correction factor is 1.1.

Step 1053, correcting the preset time length based on the first correction coefficient and the second correction coefficient to obtain the regeneration time length.

Wherein, a relational expression exists between the preset time length and the regeneration time length, and the relational expression is specifically t_heat ₁ ＝t_heat*y ₁ *y ₂ Wherein t_heat ₁ For regeneration duration, t_heat is a preset duration, y ₁ For the first correction coefficient, y ₂ Is the second correction coefficient. The relation is stored in the controller, and when the first correction coefficient and the second correction coefficient are obtained, the corresponding output, namely the regeneration time length, can be determined.

According to the thermal management control method for the diesel engine aftertreatment system, if the duty ratio of the average temperature of the particulate filter of the diesel engine in the temperature distribution is larger than the third duty ratio threshold value within the current preset duration, a first correction coefficient is determined; if the duty ratio of the current environmental temperature in the collection temperature set is larger than a fourth duty ratio threshold value, determining a second correction coefficient; and correcting the preset time based on the first correction coefficient and the second correction coefficient to obtain the regeneration time, wherein the obtained first correction coefficient and the second correction coefficient are screened, so that the accuracy of the obtained regeneration time can be improved by correcting the preset time based on the first correction coefficient and the second correction coefficient.

Fig. 3 is a thermal management control method of a diesel engine aftertreatment system according to another embodiment of the present application, as shown in fig. 3, where the thermal management control method of the diesel engine aftertreatment system according to the present embodiment includes the following steps:

step 301, obtaining an overall risk coefficient of a current operation condition of the diesel engine and a current transient condition state value.

Step 302, comparing the overall risk coefficient of the current operation condition with a first risk coefficient threshold.

And step 303, judging whether the current operation condition is a high risk condition according to the comparison result. If yes, step 305 is executed to determine that the diesel aftertreatment system satisfies the condition for entering the thermal management mode, and control the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value, so that exhaust emission is performed at the set temperature value.

When executing step 302, step 304 is also executed simultaneously, and whether the transient change of the current operation condition of the diesel engine aftertreatment system reaches the preset state is judged according to the current transient condition state value. If yes, step 305 is executed to determine that the diesel aftertreatment system satisfies the condition for entering the thermal management mode, and control the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value, so that exhaust emission is performed at the set temperature value.

If the determination results of step 303 and step 304 are both negative, step 306 is performed to determine that the diesel aftertreatment system satisfies the condition for entering the thermal management mode.

Fig. 4 is a schematic structural diagram of a thermal management control device of a diesel engine aftertreatment system according to an embodiment of the present application, as shown in fig. 4, where the thermal management control device of the diesel engine aftertreatment system according to the embodiment is located in a controller of a diesel engine, the thermal management control device of the diesel engine aftertreatment system according to the embodiment includes: a data acquisition module 41, a condition judgment module 42, and a temperature increase control module 44.

The data obtaining module 41 is configured to obtain an overall risk coefficient of a current operating condition of the diesel engine, and a current transient operating condition state value. The condition judgment module 42 is configured to judge whether the post-treatment system of the diesel engine meets the condition of entering the thermal management mode according to at least one of the overall risk coefficient of the current operation condition and the state value of the current transient condition. The temperature raising control module 44 is configured to control the temperature of the inlet exhaust gas of the particulate filter of the diesel engine to be raised to a set temperature value so that exhaust gas emission is performed at the set temperature value, if it is determined that the condition for entering the thermal management mode is satisfied.

Optionally, the condition judging module 42 is specifically configured to compare the overall risk coefficient of the current operation condition with the first risk coefficient threshold, and judge whether the current operation condition is a high risk condition according to the comparison result; judging whether the transient variation of the current operation working condition of the diesel engine aftertreatment system reaches a preset state or not according to the current transient working condition state value; if the current operation working condition is determined to be a high-risk working condition and/or the transient change of the current operation working condition reaches a preset state, determining that the diesel engine aftertreatment system meets the condition of entering a thermal management mode; if the current operation working condition is not the high risk working condition and the transient change of the current operation working condition does not reach the preset state, determining that the diesel engine aftertreatment system does not meet the condition of entering the thermal management mode.

Optionally, the data acquisition module 41 is specifically configured to, when acquiring the overall risk coefficient of the current operating condition of the diesel engine: acquiring the operation parameters of the diesel engine at each moment in the current preset time length to obtain the operation conditions of the aftertreatment system of the diesel engine at each moment in the current preset time length, wherein the operation conditions are represented by the operation parameters at the corresponding moment; based on the operation working condition at each moment and a pre-stored working condition risk mapping table, respectively determining moment risk coefficients corresponding to the operation working conditions at each moment; and determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the moment risk coefficient and the frequency occupation ratio in the current preset time.

Optionally, the data obtaining module 41 is specifically configured to, when determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the risk coefficient at the moment and the frequency of occurrence duty ratio within the current preset duration: if the moment risk coefficient is larger than the first risk coefficient threshold value, determining the moment risk coefficient as a target risk coefficient; and determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the frequency occupation ratio of the target risk coefficient in the current preset time.

Optionally, the data obtaining module 41 is specifically configured to, when determining the overall risk system of the current operation condition of the diesel engine aftertreatment system according to the frequency occupation ratio of the target risk coefficient in the current preset duration: acquiring the number of the target risk coefficients; if the number of the target risk coefficients is one, and the occurrence frequency duty ratio of the target risk coefficients in the current preset duration is larger than a first duty ratio threshold value, determining the target risk coefficients as the overall risk coefficients of the current operation working condition. If the number of the target risk coefficients is at least two, respectively determining a second duty ratio threshold corresponding to each target risk coefficient, wherein the second duty ratio threshold is inversely related to the size of the target risk coefficient; if any target risk coefficient exists, the occurrence frequency proportion of the target risk coefficient in the current preset duration is larger than a corresponding second duty ratio threshold value, and the target risk coefficient is determined to be the overall risk coefficient of the current operation condition.

Optionally, the data acquisition module 41 is specifically configured to, when acquiring the current transient operating condition state value of the diesel engine: and acquiring transient variation characteristics of the diesel engine and determining the current transient working condition state value based on the transient variation characteristics.

Optionally, the data acquisition module 41 is specifically configured to, when acquiring the transient variation characteristic of the diesel engine and determining the current transient state value based on the transient variation characteristic: acquiring driving behavior data of the diesel engine and determining the driving rough degree; acquiring the torque change rate of the diesel engine in a preset time window; determining the current transient operating condition state value according to the driving rough degree and the torque change rate; wherein the transient variation characteristics of the diesel engine include the cruising rough degree and the torque variation rate.

Optionally, the data acquisition module 41 is specifically configured to, when acquiring the driving behavior data of the diesel engine and determining the driving rough degree: acquiring the throttle opening and the throttle acceleration of the diesel engine; and determining the driving rough degree according to the accelerator opening degree and the accelerator acceleration.

Optionally, the data acquisition module 41 is specifically configured to, when acquiring the torque change rate of the diesel engine within the preset time window: respectively calculating the torque of the diesel engine at each moment in a preset time window, and calculating the torque difference value corresponding to every two adjacent moments; determining the transient change degree of the operation working condition corresponding to each two adjacent moments based on the torque difference values; calculating the ratio of the moment corresponding to the severe transient change degree of the operation working condition to all moments in the whole preset time window; the ratio is determined as a torque rate of change of the diesel engine.

Optionally, the thermal management control device of a diesel engine aftertreatment system provided in this embodiment further includes a duration update module, configured to correct the preset time based on a temperature distribution of an inlet exhaust temperature of a particulate filter of the diesel engine and a current ambient temperature, to obtain a regeneration duration; and controlling the inlet exhaust gas temperature of the particulate filter of the diesel engine to maintain a set temperature value for a regeneration duration.

Optionally, the duration updating module is specifically configured to, when the preset time is corrected based on the temperature distribution of the inlet exhaust gas temperature of the particulate filter of the diesel engine and the current ambient temperature to obtain the regeneration duration: if the ratio of the average temperature of the particulate filter of the diesel engine in the temperature distribution is larger than a third ratio threshold value within the current preset duration, a first correction coefficient is determined; if the duty ratio of the current environmental temperature in the collection temperature set is larger than a fourth duty ratio threshold value, determining a second correction coefficient; and correcting the preset time length based on the first correction coefficient and the second correction coefficient to obtain the regeneration time length.

Fig. 5 is a block diagram of an electronic device, which may be as shown in fig. 5, according to an exemplary embodiment, including: a memory 51, a processor 52; memory 51 is a memory for storing the processor-executable instructions; the processor 52 is operable to execute computer programs or instructions to implement the thermal management control method of the diesel aftertreatment system provided in any one of the embodiments above.

The memory 51 is used for storing programs. In particular, the program may include program code including computer-operating instructions. The memory 51 may comprise a high-speed RAM memory or may further comprise a non-volatile memory (non-volatile memory), such as at least one disk memory.

The processor 52 may be a central processing unit (Central Processing Unit, abbreviated as CPU), or an application specific integrated circuit (Application Specific Integrated Circuit, abbreviated as ASIC), or one or more integrated circuits configured to implement embodiments of the present disclosure.

Alternatively, in a specific implementation, if the memory 51 and the processor 52 are implemented independently, the memory 51 and the processor 52 may be connected to each other through a bus and perform communication with each other. The bus may be an industry standard architecture (Industry Standard Architecture, abbreviated ISA) bus, an external device interconnect (Peripheral Component, abbreviated PCI) bus, or an extended industry standard architecture (Extended Industry Standard Architecture, abbreviated EISA) bus, among others. The buses may be classified as address buses, data buses, control buses, etc. For ease of illustration, only one thick line is shown in fig. 1, but not only one bus or one type of bus.

Alternatively, in a specific implementation, if the memory 51 and the processor 52 are integrated on a chip, the memory 51 and the processor 52 may perform the same communication through an internal interface.

Another embodiment of the present disclosure also provides a computer-readable storage medium having stored therein computer-executable instructions that, when executed by a processor, are configured to implement a thermal management control method for a diesel aftertreatment system as provided in any one of the embodiments above.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

It is to be understood that the present disclosure is not limited to the precise arrangements and instrumentalities shown in the drawings, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A method of thermal management control of a diesel aftertreatment system, the method comprising:

acquiring the operation parameters of the diesel engine at each moment in the current preset time length to obtain the operation conditions of the aftertreatment system of the diesel engine at each moment in the current preset time length, wherein the operation conditions are represented by the operation parameters at the corresponding moment;

based on the operation working conditions at each moment and a pre-stored working condition risk mapping table, respectively determining moment risk coefficients corresponding to the operation working conditions at each moment;

determining an overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the moment risk coefficient and the frequency occupation ratio in the current preset time period;

acquiring transient variation characteristics of the diesel engine and determining a current transient working condition state value based on the transient variation characteristics; wherein, the transient change characteristic refers to the parameter characteristic of transient change in the running process of the diesel engine;

judging whether the diesel engine aftertreatment system meets the condition of entering a thermal management mode or not according to at least one of the overall risk coefficient of the current operation working condition and the state value of the current transient working condition;

if it is determined that the condition for entering the thermal management mode is satisfied, controlling the inlet exhaust temperature of the particulate filter of the diesel engine to rise to a set temperature value so that exhaust emission is performed at the set temperature value.

2. The method of claim 1, wherein said determining whether the diesel aftertreatment system satisfies a condition to enter a thermal management mode based on at least one of an overall risk factor for a current operating condition and a state value for the current transient operating condition comprises:

comparing the overall risk coefficient of the current operation working condition with a first risk coefficient threshold value, and judging whether the current operation working condition is a high risk working condition according to a comparison result;

judging whether the transient variation of the current operation condition of the diesel engine aftertreatment system reaches a preset state or not according to the current transient condition state value;

if the current operation working condition is determined to be a high-risk working condition and/or the transient change of the current operation working condition reaches a preset state, determining that the diesel engine aftertreatment system meets the condition of entering a thermal management mode;

if the current operation working condition is not the high risk working condition and the transient change of the current operation working condition does not reach the preset state, determining that the diesel engine aftertreatment system does not meet the condition of entering the thermal management mode.

3. The method of claim 2, wherein determining the overall risk factor for the current operating condition of the diesel aftertreatment system based on the magnitude of the moment risk factor and the frequency of occurrence duty cycle within the current predetermined time period comprises:

If the moment risk coefficient is larger than the first risk coefficient threshold value, determining the moment risk coefficient as a target risk coefficient;

and determining the overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the frequency occupation ratio of the target risk coefficient in the current preset time.

4. The method of claim 3, wherein said determining the overall risk factor for the current operating condition of the diesel aftertreatment system based on the frequency of occurrence of the target risk factor over the current predetermined time period comprises:

acquiring the number of the target risk coefficients;

if the number of the target risk coefficients is one, and the frequency of occurrence of the target risk coefficients in the current preset duration is larger than a first duty ratio threshold, determining the target risk coefficients as the overall risk coefficients of the current operation working condition;

if the number of the target risk coefficients is at least two, respectively determining a second duty ratio threshold corresponding to each target risk coefficient, wherein the second duty ratio threshold is inversely related to the size of the target risk coefficient;

if any target risk coefficient exists, the occurrence frequency proportion of the target risk coefficient in the current preset duration is larger than a corresponding second duty ratio threshold value, and the target risk coefficient is determined to be the overall risk coefficient of the current operation condition.

5. The method of claim 1, wherein obtaining a transient change characteristic of the diesel engine and determining the current transient operating condition state value based on the transient change characteristic comprises:

acquiring driving behavior data of the diesel engine and determining the driving rough degree;

acquiring the torque change rate of the diesel engine in a preset time window;

determining the current transient operating condition state value according to the driving rough degree and the torque change rate;

wherein the transient variation characteristics of the diesel engine include the cruising rough degree and the torque variation rate.

6. The method of claim 5, wherein obtaining the driving behavior data of the diesel engine and determining the driving rough comprises:

acquiring the throttle opening and the throttle acceleration of the diesel engine;

and determining the driving rough degree according to the accelerator opening degree and the accelerator acceleration.

7. The method of claim 5, wherein said obtaining a rate of change of torque of said diesel engine over a predetermined time window comprises:

respectively calculating the torque of the diesel engine at each moment in a preset time window, and calculating the torque difference value corresponding to every two adjacent moments;

Calculating the ratio of the corresponding moment to all moments in the whole preset time window when the torque difference value does not fall in the preset difference value range;

the ratio is determined as a torque rate of change of the diesel engine.

8. The method of claim 7, wherein after the temperature of the inlet exhaust gas of the particulate filter of the diesel engine is raised to the set temperature value, further comprising:

correcting the preset time based on the temperature distribution of the inlet exhaust temperature of the particle filter of the diesel engine and the current environment temperature to obtain regeneration time;

and controlling the inlet exhaust gas temperature of the particulate filter of the diesel engine to maintain a set temperature value for a regeneration duration.

9. The method of claim 8, wherein modifying the preset time to obtain a regeneration duration based on a temperature profile of an inlet exhaust temperature of a particulate filter of the diesel engine and a current ambient temperature comprises:

if the ratio of the average temperature of the particulate filter of the diesel engine in the temperature distribution is larger than a third ratio threshold value within the current preset duration, a first correction coefficient is determined;

if the duty ratio of the current environmental temperature in the collection temperature set is larger than a fourth duty ratio threshold value, determining a second correction coefficient;

And correcting the preset time based on the first correction coefficient and the second correction coefficient to obtain the regeneration duration.

10. A thermal management control device for a diesel aftertreatment system, the device comprising:

the data acquisition module is used for acquiring the operation parameters of the diesel engine at each moment in the current preset time length so as to obtain the operation conditions of the diesel engine aftertreatment system at each moment in the current preset time length, wherein the operation conditions are represented by the operation parameters at the corresponding moment; based on the operation working conditions at each moment and a pre-stored working condition risk mapping table, respectively determining moment risk coefficients corresponding to the operation working conditions at each moment; determining an overall risk coefficient of the current operation condition of the diesel engine aftertreatment system according to the magnitude of the moment risk coefficient and the frequency occupation ratio in the current preset time period; acquiring transient variation characteristics of the diesel engine and determining a current transient working condition state value based on the transient variation characteristics; wherein, the transient change characteristic refers to the parameter characteristic of transient change in the running process of the diesel engine;

11. An electronic device, comprising: a memory, a processor; the memory is used for storing the processor executable instructions; the processor is configured to execute a computer program or instructions to implement a method of thermal management control of a diesel aftertreatment system according to any one of claims 1 to 9.

12. A computer readable storage medium, wherein computer executable instructions are stored in the computer readable storage medium, which when executed by a processor are adapted to implement the thermal management control method of a diesel aftertreatment system according to any one of claims 1 to 9.