Transient torque control method of parallel hybrid power system and related device

Abstract

The invention discloses a transient torque control method of a parallel hybrid power system and a related device, and relates to the technical field of hybrid diesel engines. When a whole vehicle is in a hybrid power mode, the torque demand state of the diesel engine is determined; if the torque demand state is torque increase, the working mode of the diesel engine is obtained, and the torque increase step length of the diesel engine is determined according to the working mode; and controlling the diesel engine to output torque according to the torque increasing step length. Under the transient working condition that the torque is increased, the torque increasing step length of the diesel engine can be determined according to the working mode of the diesel engine so as to control the diesel engine to output the torque, so that the torque increasing step length of the diesel engine can adapt to the working mode of the diesel engine, NOx original emission is converted in time in aftertreatment, the NOx tail emission peak value is reduced, and emission is prevented from exceeding the standard.

Description

Technical Field

[0001] The present application relates to the technical field of hybrid diesel engines, and in particular to a transient torque control method and related devices for a parallel hybrid system. Background Art

[0002] At present, hybrid diesel vehicles increase diesel engine output torque at a fixed step size under transient torque increase conditions. If the step size is too large, the diesel engine will quickly reach the high load area, resulting in NO x The original emission is high. Once the diesel engine aftertreatment temperature is low and the ammonia storage is small, the aftertreatment cannot convert NO in time. x Original row, NO appears x Tail exhaust peak, causing emissions to exceed the standard. Summary of the invention

[0003] In view of the above problems, the present application provides a method and a related device for transient torque control of a parallel hybrid system to reduce NOx in transient conditions of torque increase. x The purpose of the tail peak. The specific plan is as follows:

[0004] A first aspect of the present application provides a method for controlling transient torque of a parallel hybrid system, the method comprising:

[0005] When the vehicle is in hybrid mode, determine the torque demand state of the diesel engine;

[0006] If the torque demand state is torque increase, obtaining the working mode of the diesel engine, and determining the torque increase step length of the diesel engine according to the working mode;

[0007] The diesel engine is controlled to output torque according to the torque increase step.

[0008] In a possible implementation, the working mode includes a heating mode, and determining the torque increase step of the diesel engine according to the working mode includes:

[0009] Obtain the temperature before SCR, the SCR ammonia storage value, and the NO x Original row value;

[0010] determining a first torque increase rate in the heating mode according to the pre-SCR temperature and the SCR ammonia storage value, wherein the first torque increase rate is positively correlated with the pre-SCR temperature and the SCR ammonia storage value;

[0011] Determine the NO x The first correction factor that matches the original row value;

[0012] A first torque increase step length in the heating mode is calculated using the first torque increase rate and the first correction coefficient.

[0013] In a possible implementation, the working mode includes a regeneration mode, and determining the torque increase step of the diesel engine according to the working mode includes:

[0014] Obtaining a first excess air coefficient;

[0015] determining a second torque increase rate in the regeneration mode according to the first excess air coefficient, wherein the second torque increase rate is positively correlated with the first excess air coefficient;

[0016] The second torque increase rate is used as a second torque increase step size in the regeneration mode.

[0017] In a possible implementation, the working mode includes a normal mode, and determining the torque increase step of the diesel engine according to the working mode includes:

[0018] Obtaining DPF carbon load and second excess air coefficient;

[0019] determining a third torque increase rate in the normal mode according to the DPF carbon load and the second excess air coefficient, wherein the third torque increase rate is negatively correlated with the DPF carbon load and positively correlated with the second excess air coefficient;

[0020] The third torque increase rate is used as a third torque increase step size in the normal mode.

[0021] In a possible implementation, the transient torque control method of the parallel hybrid system further includes:

[0022] If the torque demand state is torque reduction, obtaining intake manifold pressure, actual intake air flow rate and pressure before the supercharger;

[0023] determining a torque reduction rate according to the intake manifold pressure and the actual intake air flow rate;

[0024] Determining a standard intake flow rate of a surge line according to the intake manifold pressure and the pressure before the supercharger, and calculating a surge margin using the actual intake flow rate and the standard intake flow rate;

[0025] determining a second correction coefficient matching the surge margin, wherein the second correction coefficient is positively correlated with the surge margin;

[0026] calculating a torque reduction step length using the torque reduction rate and the second correction coefficient;

[0027] The diesel engine is controlled to output torque according to the torque reduction step.

[0028] A second aspect of the present application provides a transient torque control device for a parallel hybrid system, the transient torque control device for the parallel hybrid system comprising:

[0029] A state determination module, used to determine the torque demand state of the diesel engine when the vehicle is in a hybrid mode;

[0030] The first torque control module is used to obtain the working mode of the diesel engine if the torque demand state is torque increase, and determine the torque increase step of the diesel engine according to the working mode; and control the diesel engine to output torque according to the torque increase step.

[0031] In a possible implementation, the transient torque control device of the parallel hybrid system further includes:

[0032] The second torque control module is used to obtain the intake manifold pressure, the actual intake flow rate and the pressure before the supercharger if the torque demand state is torque reduction; determine the torque reduction rate according to the intake manifold pressure and the actual intake flow rate; determine the standard intake flow rate of the surge line according to the intake manifold pressure and the pressure before the supercharger, and calculate the surge margin using the actual intake flow rate and the standard intake flow rate; determine a second correction coefficient that matches the surge margin, the second correction coefficient is positively correlated with the surge margin; calculate the torque reduction step length using the torque reduction rate and the second correction coefficient; and control the diesel engine to output torque according to the torque reduction step length.

[0033] A third aspect of the present application provides a computer program product, comprising computer-readable instructions. When the computer-readable instructions are executed on an electronic device, the electronic device implements the transient torque control method of a parallel hybrid system according to the first aspect or any implementation of the first aspect.

[0034] A fourth aspect of the present application provides an electronic device, comprising at least one processor and a memory connected to the processor, wherein:

[0035] The memory is used to store computer programs;

[0036] The processor is used to execute the computer program so that the electronic device can implement the transient torque control method of the parallel hybrid system according to the first aspect or any implementation method of the first aspect.

[0037] In a fifth aspect, the present application provides a computer storage medium, which carries one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can implement the transient torque control method of the parallel hybrid system according to the first aspect or any implementation method of the first aspect.

[0038] By means of the above technical solution, the present application provides a method and related device for transient torque control of a parallel hybrid system. When the vehicle is in hybrid mode, the torque demand state of the diesel engine is determined; if the torque demand state is torque increase, the working mode of the diesel engine is obtained, and the torque increase step length of the diesel engine is determined according to the working mode; the diesel engine is controlled to output torque according to the torque increase step length. Under the transient working condition of torque increase, the present application can determine the torque increase step length according to the working mode of the diesel engine, so as to control the diesel engine to output torque, which can make the torque increase step length of the diesel engine adapt to its working mode, so that the post-processing can convert NO in time. x Original discharge, reducing NO x Tail emission peak value to avoid exceeding emission standards. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. Throughout the accompanying drawings, the same or similar reference numerals represent the same or similar elements. It should be understood that the drawings are schematic and the originals and elements are not necessarily drawn to scale.

[0040] Figure 1 A schematic flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application;

[0041] Figure 2 A schematic diagram of a partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application;

[0042] Figure 3 Another partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application;

[0043] Figure 4 Another partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application;

[0044] Figure 5 A schematic structural diagram of a transient torque control device for a parallel hybrid system provided in an embodiment of the present application;

[0045] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following describes the embodiments of the present application in conjunction with the drawings in the embodiments of the present application. The terms used in the implementation method section of the present application are only used to explain the specific embodiments of the present application, and are not intended to limit the present application.

[0047] The embodiments of the present application are described below in conjunction with the accompanying drawings. Those skilled in the art will appreciate that, with the development of technology and the emergence of new scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0048] The terms "first", "second" etc. in the specification of the application and the above-mentioned drawings are used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the terms used in this way can be interchangeable in appropriate circumstances, and this is only to describe the distinction mode adopted by the objects of the same attributes when describing in the embodiments of the application. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, so that the process, method, system, product or equipment comprising a series of units need not be limited to those units, but may include other units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0049] In order to reduce NO as torque increases x Tail exhaust peak value, the embodiment of the present application provides a method for controlling transient torque of a parallel hybrid system. The following is a detailed description of the method for controlling transient torque of a parallel hybrid system according to the embodiment of the present application in conjunction with the accompanying drawings.

[0050] To facilitate understanding of this application, the following describes the relevant concepts involved in this application:

[0051] SCR (Selective Catalytic Reduction) is a part of diesel engine aftertreatment, which is aimed at NO in diesel vehicle exhaust emissions. x A treatment process in which ammonia or urea, a reducing agent, is injected into the SCR post-treatment system to reduce NO in diesel engine exhaust gas under the action of a catalyst. x Reduced to nitrogen (N2) and water (H2O).

[0052] DPF (Diesel Particulate Filter): It is a part of diesel engine aftertreatment and is located after DOC. DPF captures particulate matter in exhaust gas by physical blocking, and these particulate matter accumulates in the filter to form carbon load. When the carbon load reaches a certain level, DPF needs to be regenerated to remove these particulate matter.

[0053] DOC (Diesel Oxidation Catalyst): The main functions are: ① Remove hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas and convert them into harmless carbon dioxide (CO2) and water (H2O); ② When the diesel engine enters the regeneration mode, the diesel in the exhaust reacts with oxygen inside the DOC to increase the exhaust temperature and remove carbon particles in the DPF post-treatment.

[0054] NO x : One of the pollutants emitted by diesel engines. Diesel engines generate more pollutants at high loads and need to be eliminated through SCR post-treatment. SCR post-treatment can only convert NO at above 200°C x , the conversion efficiency is higher at 250℃-350℃. x In the SCR, NO is converted into urea by the injected urea and the ammonia stored in the SCR (ammonia generated by the hydrolysis of urea). x Reduced to N2 and O2.

[0055] Surge: A vibration phenomenon under abnormal operating conditions that occurs when the intake air flow rate decreases to a certain extent. This vibration phenomenon will cause strong mechanical vibration and hot end overheating of the compressor, and cause serious damage to components in a short period of time. According to the supercharger surge map, the surge risk can be calculated based on the intake pressure and intake volume.

[0056] See also Figure 1 , Figure 1 The figure is a flow chart of a transient torque control method of a parallel hybrid system provided in an embodiment of the present application. Figure 1 As shown, a method for controlling transient torque of a parallel hybrid system provided in an embodiment of the present application may include steps S10 to S30. These steps are described in detail below.

[0057] S10, when the vehicle is in a hybrid mode, determining a torque demand state of the diesel engine.

[0058] In the embodiment of the present application, the whole vehicle is in hybrid mode, and the whole vehicle controller determines the required torque of the whole vehicle according to the depth of the accelerator pedal, and then allocates the required torques to the motor and the diesel engine considering the operating state of the whole vehicle, that is, the required torque of the whole vehicle is equal to the required torque of the motor and the required torque of the diesel engine.

[0059] In this regard, for a diesel engine, its torque demand state can be determined according to its diesel engine demand torque under continuous steps. For example, if the driver suddenly steps on the accelerator, the vehicle's demand torque will increase transiently, which will cause the diesel engine's demand torque to increase transiently. At this time, the diesel engine's torque demand state is torque increase. To continue with the example, if the driver releases the accelerator, the vehicle's demand torque will decrease transiently, which will cause the diesel engine's demand torque to decrease transiently. At this time, the diesel engine's torque demand state is torque decrease.

[0060] Of course, under conditions such as vehicle acceleration or climbing, the power demand of the entire vehicle will be very large. If the accelerator pedal depth is greater than a certain value (such as 80%), the motor's required torque reaches the maximum value of the motor's output torque and cannot meet the vehicle's required torque. At this time, in order to prioritize the vehicle's power output, the diesel engine no longer increases its output torque according to the step size, but outputs it according to the diesel engine's required torque.

[0061] S20: If the torque demand state is torque increase, obtain the working mode of the diesel engine, and determine the torque increase step of the diesel engine according to the working mode.

[0062] In the embodiment of the present application, if the torque demand state is torque increase, the working mode of the diesel engine can be determined according to the pre-SCR temperature and the DPF carbon load. Specifically, if the DPF carbon load is high, the working mode is the regeneration mode; if the DPF carbon load is within the normal range and the pre-SCR temperature is low, the working mode is the heating mode, and if the pre-SCR temperature is within the normal range, the working mode is the normal mode.

[0063] Based on this, taking into account the control objectives of different working modes, the torque increase step of the diesel engine in different working modes can be determined.

[0064] In a possible implementation, when the working mode is heating mode, the temperature before SCR is low, generally below 230°C, and the post-treatment conversion efficiency is low, with emission control as the primary goal. Figure 2 , Figure 2 A schematic diagram of a partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application. Figure 2 As shown, an embodiment of the present application provides a method for transient torque control of a parallel hybrid system, wherein "determining the torque increase step of the diesel engine according to the working mode" in step S20 may include steps S2011 to S2014. These steps are described in detail below.

[0065] S2011, obtain the temperature before SCR, SCR ammonia storage value, and NO x Original row value.

[0066] In the embodiment of the present application, the temperature before the SCR and the NO at the current moment are obtained by collecting relevant sensors. x The original emission value, in addition, the SCR ammonia storage value is obtained through the ammonia storage model.

[0067] S2012, determining a first torque increase rate in the heating mode according to the pre-SCR temperature and the SCR ammonia storage value, wherein the first torque increase rate is positively correlated with the pre-SCR temperature and the SCR ammonia storage value.

[0068] The higher the temperature before SCR, the higher the NO x The higher the conversion efficiency, the higher the conversion efficiency. x The original high emission can also be converted inside the SCR, making NO x The tail exhaust is maintained at a low level. The SCR ammonia storage refers to the amount of ammonia in the gaseous state in the gaps inside the SCR. x When passing through the SCR, ammonia and NO are released inside the SCR. x reaction, the higher the SCR ammonia storage, the higher the NO x Therefore, when the temperature before SCR is high and the CR ammonia storage value is high, a higher NO x Original displacement, the output torque of the diesel engine can be increased at a greater rate.

[0069] In this regard, in the embodiment of the present application, the torque increase rate corresponding to the pre-SCR temperature and the SCR ammonia storage value is determined by a table lookup method, and the torque increase rate is the first torque increase rate in the heating mode. Specifically, the first torque increase rate is positively correlated with the pre-SCR temperature, and the first torque increase rate is positively correlated with the SCR ammonia storage value, that is, the higher the pre-SCR temperature and the higher the SCR ammonia storage value, the greater the first torque increase rate. See Table 1, which illustrates the first torque increase rate corresponding to different pre-SCR temperatures and SCR ammonia storage values.

[0070] Table 1

[0071]

[0072] S2013, OK and NO x The first correction factor to match the original row value.

[0073] In the present application, NO x When the original displacement exceeds a certain value, the first correction coefficient used to correct the first torque increase rate and NO x The original row value is negatively correlated, that is, NO x The higher the original discharge value, the smaller the first correction coefficient is, so as to reduce NO x The original method avoids NO x The tail exhaust is too high. The reasons are as follows:

[0074] 1) In NO x Under certain conversion efficiency, NO x The higher the original discharge, the higher the NO x The tail row is also higher, so when NO x When the original displacement exceeds a certain value, it is necessary to reduce the torque increase rate of the diesel engine to reduce the high-load operation time of the diesel engine; 2) NO x The higher the original emission, the more urea the SCR needs to inject. Continuous injection of a large amount of urea can easily lead to incomplete hydrolysis of urea, resulting in urea crystals at the front end of the SCR, which will cause the SCR conversion efficiency to continue to decrease. See Table 2, which shows different NO x The first correction coefficient corresponding to the original row value.

[0075] Table 2

[0076]

[0077] S2014: Calculate a first torque increase step in the heating mode using the first torque increase rate and the first correction coefficient.

[0078] In the embodiment of the present application, the product of the first torque increase rate and the first correction coefficient may be used as the torque increase step in the heating mode, that is, the first torque increase step.

[0079] In a possible implementation, when the working mode is the regeneration mode, since sufficient oxygen is required, the torque increase step size can be controlled to avoid the problem of too low oxygen concentration during the regeneration process leading to slow regeneration rate. Figure 3 , Figure 3 Another partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application. Figure 3 As shown, an embodiment of the present application provides a method for transient torque control of a parallel hybrid system, wherein "determining the torque increase step of the diesel engine according to the working mode" in step S20 may include steps S2021 to S2023. These steps are described in detail below.

[0080] S2021, obtaining the first excess air coefficient.

[0081] In regeneration mode, the diesel engine injects fuel into the cylinder during the exhaust stroke, and needs to burn with oxygen in the exhaust gas during post-processing. If the excess air coefficient in the intake air is too small, the oxygen content in the exhaust gas will be reduced, the diesel in the exhaust gas will not get enough oxygen to burn, and the post-processing will not get enough temperature, resulting in slow regeneration of the DPF post-processing. In this regard, when the excess air coefficient is low, the increase in the injection amount can be reduced by limiting the torque increase step length to maintain sufficient oxygen in the exhaust gas.

[0082] In the embodiment of the present application, the excess air coefficient at the current moment, i.e., the first excess air coefficient, can be calculated by the intake flow rate and the injection amount. Specifically, the excess air coefficient = intake flow rate / injection amount / 14.3 (14.3 kg of air is required for the complete combustion of 1 kg of diesel). When the excess air coefficient is 1, the diesel and air sprayed out can react completely at this time, but since the diesel atomization in the diesel engine cylinder is not bright and there is a local lack of air, the excess air coefficient of the diesel engine is generally greater than 1.

[0083] S2022: Determine a second torque increase rate in the regeneration mode according to the first excess air coefficient, where the second torque increase rate is positively correlated with the first excess air coefficient.

[0084] In the embodiment of the present application, the torque increase rate corresponding to the first excess air coefficient is determined by a table lookup method, and the torque increase rate is the second torque increase rate in the regeneration mode. Specifically, the second torque increase rate is positively correlated with the first excess air coefficient, that is, the higher the first excess air coefficient, the greater the second torque increase rate. See Table 3, which illustrates the second torque increase rate corresponding to different first excess air coefficients.

[0085] Table 3

[0086]

[0087] S2023: Using the second torque increase rate as the second torque increase step in the regeneration mode.

[0088] In the embodiment of the present application, the second torque increase rate is used as the torque increase step in the regeneration mode, that is, the second torque increase step.

[0089] In a possible implementation, when the working mode is normal mode, the temperature before the SCR is high, and the NO x The conversion efficiency is high, and the transient condition is aimed at controlling smoke density. Figure 4 , Figure 4 Another partial flow chart of a transient torque control method for a parallel hybrid system provided in an embodiment of the present application. Figure 4 As shown, an embodiment of the present application provides a method for transient torque control of a parallel hybrid system, wherein "determining the torque increase step of the diesel engine according to the working mode" in step S20 may include steps S2031 to S2033. These steps are described in detail below.

[0090] S2031, obtaining the DPF carbon load and the second excess air coefficient.

[0091] During the combustion process of a diesel engine, the smaller the excess air coefficient, the worse the combustion, and the more likely it is to produce large amounts of soot. Therefore, when the excess air coefficient is small, the transient torque should increase slowly, so that the amount of fuel injection can increase slowly and the generation of soot can be reduced as much as possible. On the contrary, when the excess air coefficient is large, it means that the intake air is sufficient and the torque can be increased in larger steps, and there will not be much soot at this time. In addition, the DPF carbon load reflects the degree of soot accumulation in the DPF post-treatment. When the DPF carbon load is high, it is necessary to slow down the increase in torque to avoid too fast an increase in torque, resulting in a high soot value, causing the DPF carbon load to increase too quickly and triggering the regeneration mode. In the regeneration mode, the diesel engine needs to inject additional diesel into the cylinder, which enters the post-treatment with the exhaust gas. The oxygen involved in the combustion in the DOC post-treatment and the exhaust gas will generate high temperatures (about 600°C) to burn the carbon captured in the DPF post-treatment. This process will increase the fuel consumption of the vehicle. In this regard, the present application reduces the transient smoke density during the torque increase process to avoid causing the carbon load of the DPF post-treatment to increase too quickly, delays the time to enter the regeneration mode as much as possible, and reduces the fuel consumption of the entire vehicle.

[0092] In the embodiment of the present application, the DPF carbon load can be obtained through the internal carbon load model. In addition, the excess air coefficient at the current moment, that is, the second excess air coefficient, is calculated by the intake flow rate and the fuel injection amount.

[0093] S2032: Determine a third torque increase rate in the normal mode according to the DPF carbon load and the second excess air coefficient, where the third torque increase rate is negatively correlated with the DPF carbon load and positively correlated with the second excess air coefficient.

[0094] In the embodiment of the present application, the torque increase rate corresponding to the DPF carbon load and the second excess air coefficient is determined by a table lookup method, and the torque increase rate is the third torque increase rate in the normal mode. Specifically, the third torque increase rate is negatively correlated with the DPF carbon load, and the third torque increase rate is positively correlated with the second excess air coefficient, that is, the higher the DPF carbon load, the smaller the third torque increase rate, and the higher the second excess air coefficient, the greater the third torque increase rate. See Table 4, which illustrates the third torque increase rate corresponding to different DPF carbon loads and second excess air coefficients.

[0095] Table 4

[0096]

[0097] S2033: Use the third torque increase rate as the third torque increase step in the normal mode.

[0098] In the embodiment of the present application, the third torque increase rate is used as the torque increase step in the normal mode, that is, the third torque increase step.

[0099] S30, controlling the diesel engine to output torque according to the torque increase step.

[0100] In the embodiment of the present application, after obtaining the torque increase step length, the output torque of the diesel engine at the current step length can be calculated. Specifically, assuming that the torque increase step length is △T1 and the output torque of the diesel engine at the previous step length is T1 -1 , then the output torque of the diesel engine at the current step length is T1=T1 -1 +△T1. Of course, in actual applications, when controlling the diesel engine to output torque, the smaller output value can be obtained between the output torque T1 at the current step length and the required torque of the diesel engine.

[0101] In one possible implementation, when the torque decreases, the diesel engine stops injecting fuel instantly, the intake volume decreases instantly, and the supercharger turbine shaft cannot respond immediately due to inertia, so that the supercharger speed and boost ratio remain unchanged for a certain period of time. This is reflected in the supercharger surge map, which runs from right to left and approaches a horizontal line. It will quickly approach the surge line. If the diesel engine torque drops too quickly, it will exceed the surge line, causing the supercharger to surge. In order to avoid diesel engine surge when the torque decreases and to improve the transient performance of the diesel engine, the embodiment of the present application sets the torque reduction rate according to the supercharger surge map. In this regard, the embodiment of the present application provides a transient torque control method for a parallel hybrid system, which also includes the following steps:

[0102] If the torque demand state is torque reduction, obtain the intake manifold pressure, actual intake flow and pressure before the supercharger; determine the torque reduction rate according to the intake manifold pressure and the actual intake flow; determine the standard intake flow of the surge line according to the intake manifold pressure and the pressure before the supercharger, and calculate the surge margin using the actual intake flow and the standard intake flow; determine a second correction coefficient that matches the surge margin, the second correction coefficient is positively correlated with the surge margin; calculate the torque reduction step using the torque reduction rate and the second correction coefficient; and control the diesel engine to output torque according to the torque reduction step.

[0103] In the embodiment of the present application, if the torque demand state is torque reduction, the intake manifold pressure, actual intake flow rate and pressure before the supercharger are obtained through relevant sensors. On the one hand, the torque reduction rate corresponding to the intake manifold pressure and the actual intake flow rate is determined by table lookup. On the other hand, the ratio of the intake manifold pressure to the pressure before the supercharger is used as the boost ratio, and the supercharger surge map is queried with the boost ratio to determine the intake flow rate of the surge line, that is, the standard intake flow rate, and then the actual intake flow rate and the standard intake flow rate are used to calculate the surge margin, surge margin = (actual intake flow rate-standard intake flow rate) / standard intake flow rate, and further, the second correction coefficient for correcting the torque reduction rate corresponding to the surge margin is determined by table lookup, and the second correction coefficient is positively correlated with the surge margin, that is, the larger the surge margin, the larger the second correction coefficient. See Table 5, which illustrates the second correction coefficient corresponding to different surge margins.

[0104] Table 5

[0105]

[0106] Further, the product of the torque reduction rate and the second correction coefficient is taken as the torque reduction step length, and the output torque of the diesel engine at the current step length is calculated with the torque reduction step length.

[0107] Specifically, assuming that the torque reduction step is △T2 and the output torque of the diesel engine at the previous step is T2 -1 , then the output torque of the diesel engine at the current step length is T2=T2 -1 +△T2.

[0108] Through the above description, the instantaneous torque control method of a parallel hybrid system provided in the embodiment of the present application can reduce the NO x On the one hand, it can reduce the tail exhaust peak to avoid exceeding the emission standard; on the other hand, it can reduce the transient smoke peak to prevent excessive carbon deposition; on the other hand, it can avoid regeneration interruption; on the other hand, it can avoid supercharger surge.

[0109] A method for controlling transient torque of a parallel hybrid system provided in an embodiment of the present application is introduced above. A device for executing the method for controlling transient torque of a parallel hybrid system will be introduced below.

[0110] See also Figure 5 , Figure 5 The schematic diagram of the structure of a transient torque control device for a parallel hybrid system provided in an embodiment of the present application is shown in FIG. Figure 5 As shown, an embodiment of the present application provides a transient torque control device for a parallel hybrid system, comprising:

[0111] The state determination module 10 is used to determine the torque demand state of the diesel engine when the vehicle is in the hybrid mode;

[0112] The first torque control module 20 is used to obtain the working mode of the diesel engine if the torque demand state is torque increase, and determine the torque increase step of the diesel engine according to the working mode; and control the diesel engine to output torque according to the torque increase step.

[0113] In a possible implementation, the working mode includes a heating mode, and the first torque control module 20 for determining the torque increase step of the diesel engine according to the working mode is specifically configured to:

[0114] Obtain the temperature before SCR, SCR ammonia storage value, and NO of diesel engine x Original exhaust value; determine the first torque increase rate in the heating mode according to the pre-SCR temperature and the SCR ammonia storage value, the first torque increase rate is positively correlated with the pre-SCR temperature and the SCR ammonia storage value; determine the NO x A first correction coefficient that matches the original displacement value; and a first torque increase step length in the heating mode are calculated using the first torque increase rate and the first correction coefficient.

[0115] In a possible implementation, the working mode includes a regeneration mode, and the first torque control module 20 for determining the torque increase step of the diesel engine according to the working mode is specifically configured to:

[0116] Acquire a first excess air coefficient; determine a second torque increase rate in the regeneration mode according to the first excess air coefficient, the second torque increase rate being positively correlated with the first excess air coefficient; and use the second torque increase rate as a second torque increase step in the regeneration mode.

[0117] In a possible implementation, the working mode includes a normal mode, and the first torque control module 20 for determining the torque increase step of the diesel engine according to the working mode is specifically configured to:

[0118] Obtain the DPF carbon load and the second excess air coefficient; determine a third torque increase rate in normal mode according to the DPF carbon load and the second excess air coefficient, the third torque increase rate is negatively correlated with the DPF carbon load and positively correlated with the second excess air coefficient; use the third torque increase rate as the third torque increase step in normal mode.

[0119] In a possible implementation, the transient torque control device of the parallel hybrid system further includes:

[0120] The second torque control module is used to obtain the intake manifold pressure, the actual intake flow rate and the pressure before the supercharger if the torque demand state is torque reduction; determine the torque reduction rate according to the intake manifold pressure and the actual intake flow rate; determine the standard intake flow rate of the surge line according to the intake manifold pressure and the pressure before the supercharger, and calculate the surge margin using the actual intake flow rate and the standard intake flow rate; determine a second correction coefficient that matches the surge margin, the second correction coefficient is positively correlated with the surge margin; calculate the torque reduction step length using the torque reduction rate and the second correction coefficient; and control the diesel engine to output torque according to the torque reduction step length.

[0121] It should be noted that the detailed functions of each module in the embodiment of the present application can be found in the corresponding disclosed part of the embodiment of the transient torque control method of the parallel hybrid system mentioned above, and will not be repeated here.

[0122] The present application also provides an electronic device in an embodiment. Figure 6 , Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device in the embodiment of the present application may include but is not limited to fixed terminals such as mobile phones, laptops, PDAs (personal digital assistants), PADs (tablet computers), desktop computers, etc. Figure 6 The electronic device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0123] like Figure 6 As shown, the electronic device may include a processing device (e.g., a central processing unit, a graphics processing unit, etc.) 601, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 602 or a program loaded from a storage device 608 to a random access memory (RAM) 603. When the electronic device is powered on, various programs and data required for the operation of the electronic device are also stored in the RAM 603. The processing device 601, the ROM 602, and the RAM 603 are connected to each other via a bus 604. An input / output (I / O) interface 605 is also connected to the bus 604.

[0124] Typically, the following devices may be connected to the I / O interface 605: an input device 606 including, for example, a touch screen, a touch pad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 607 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 608 including, for example, a memory card, a hard disk, etc.; and a communication device 609. The communication device 609 may allow the electronic device to communicate with other devices wirelessly or by wire to exchange data. Although Figure 6An electronic device having various devices is shown, but it should be understood that it is not required to implement or possess all the devices shown. More or fewer devices may be implemented or possessed instead.

[0125] An embodiment of the present application also provides a computer program product including computer-readable instructions. When the computer-readable instructions are executed on an electronic device, the electronic device implements any method for transient torque control of a parallel hybrid system provided in the embodiment of the present application.

[0126] A computer-readable storage medium is also provided in an embodiment of the present application. The storage medium carries one or more computer programs. When the one or more computer programs are executed by an electronic device, the electronic device can implement any of the transient torque control methods for the parallel hybrid system provided in the embodiment of the present application.

[0127] It should also be noted that the device embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed over multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. In addition, in the drawings of the device embodiments provided by the present application, the connection relationship between the modules indicates that there is a communication connection between them, which may be specifically implemented as one or more communication buses or signal lines.

[0128] Through the description of the above implementation mode, the technicians in the field can clearly understand that the present application can be implemented by means of software plus necessary general hardware, and of course, it can also be implemented by special hardware including special integrated circuits, special CPUs, special memories, special components, etc. In general, all functions completed by computer programs can be easily implemented by corresponding hardware, and the specific hardware structure used to implement the same function can also be various, such as analog circuits, digital circuits or special circuits. However, for the present application, software program implementation is a better implementation mode in more cases. Based on such an understanding, the technical solution of the present application is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a readable storage medium, such as a computer floppy disk, a U disk, a mobile hard disk, a ROM, a RAM, a magnetic disk or an optical disk, etc., including a number of instructions to enable a computer device (which can be a personal computer, a training device, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0129] In the above embodiments, all or part of the embodiments may be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments may be implemented in the form of a computer program product.

[0130] The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer may be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions may be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a website site, a computer, a training device, or a data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, training device, or data center. The computer-readable storage medium may be any available medium that a computer can store or a data storage device such as a training device, a data center, etc. that includes one or more available media integrations. The available medium may be a magnetic medium, (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)), etc.

Claims

1. A method for transient torque control of a parallel hybrid system, characterized in that: The transient torque control method of the parallel hybrid system includes: When the vehicle is in hybrid mode, determine the torque demand state of the diesel engine; If the torque demand state is torque increase, obtaining the working mode of the diesel engine, and determining the torque increase step length of the diesel engine according to the working mode; The diesel engine is controlled to output torque according to the torque increase step.

2. The method for controlling the transient torque of a parallel hybrid system according to claim 1, characterized in that: The working mode includes a heating mode, and determining the torque increase step of the diesel engine according to the working mode includes: Obtain the temperature before SCR, the SCR ammonia storage value, and the NO x Original row value; determining a first torque increase rate in the heating mode according to the pre-SCR temperature and the SCR ammonia storage value, wherein the first torque increase rate is positively correlated with the pre-SCR temperature and the SCR ammonia storage value; Determine the NO x The first correction factor that matches the original row value; A first torque increase step length in the heating mode is calculated using the first torque increase rate and the first correction coefficient.

3. The transient torque control method of a parallel hybrid system according to claim 1, characterized in that: The working mode includes a regeneration mode, and determining the torque increase step of the diesel engine according to the working mode includes: Obtaining a first excess air coefficient; determining a second torque increase rate in the regeneration mode according to the first excess air coefficient, wherein the second torque increase rate is positively correlated with the first excess air coefficient; The second torque increase rate is used as a second torque increase step size in the regeneration mode.

4. The method for transient torque control of a parallel hybrid system according to claim 1, characterized in that: The working mode includes a normal mode, and determining the torque increase step of the diesel engine according to the working mode includes: Obtaining DPF carbon load and second excess air coefficient; determining a third torque increase rate in the normal mode according to the DPF carbon load and the second excess air coefficient, wherein the third torque increase rate is negatively correlated with the DPF carbon load and positively correlated with the second excess air coefficient; The third torque increase rate is used as a third torque increase step size in the normal mode.

5. The method for controlling transient torque of a parallel hybrid system according to claim 1, characterized in that: The transient torque control method of the parallel hybrid system further includes: If the torque demand state is torque reduction, obtaining intake manifold pressure, actual intake air flow rate and pressure before the supercharger; determining a torque reduction rate according to the intake manifold pressure and the actual intake air flow rate; Determining a standard intake flow rate of a surge line according to the intake manifold pressure and the pressure before the supercharger, and calculating a surge margin using the actual intake flow rate and the standard intake flow rate; determining a second correction coefficient matching the surge margin, wherein the second correction coefficient is positively correlated with the surge margin; calculating a torque reduction step length using the torque reduction rate and the second correction coefficient; The diesel engine is controlled to output torque according to the torque reduction step.

6. A transient torque control device for a parallel hybrid system, characterized in that: The transient torque control device of the parallel hybrid system comprises: A state determination module, used to determine the torque demand state of the diesel engine when the vehicle is in a hybrid mode; The first torque control module is used to obtain the working mode of the diesel engine if the torque demand state is torque increase, and determine the torque increase step of the diesel engine according to the working mode; and control the diesel engine to output torque according to the torque increase step.

7. The transient torque control device of the parallel hybrid system according to claim 6, characterized in that: The transient torque control device of the parallel hybrid system further includes: The second torque control module is used to obtain the intake manifold pressure, the actual intake flow rate and the pressure before the supercharger if the torque demand state is torque reduction; determine the torque reduction rate according to the intake manifold pressure and the actual intake flow rate; determine the standard intake flow rate of the surge line according to the intake manifold pressure and the pressure before the supercharger, and calculate the surge margin using the actual intake flow rate and the standard intake flow rate; determine a second correction coefficient that matches the surge margin, the second correction coefficient is positively correlated with the surge margin; calculate the torque reduction step length using the torque reduction rate and the second correction coefficient; and control the diesel engine to output torque according to the torque reduction step length.

8. A computer program product, characterized in that The method comprises computer-readable instructions, and when the computer-readable instructions are executed on an electronic device, the electronic device implements the transient torque control method of a parallel hybrid system as claimed in any one of claims 1 to 5.

9. An electronic device, characterized in that: The method comprises at least one processor and a memory connected to the processor, wherein: The memory is used to store computer programs; The processor is used to execute the computer program so that the electronic device can implement the transient torque control method of the parallel hybrid system as described in any one of claims 1 to 5.

10. A computer storage medium, characterized in that: The storage medium carries one or more computer programs, and when the one or more computer programs are executed by an electronic device, the electronic device can implement the transient torque control method of the parallel hybrid system as described in any one of claims 1 to 5.

Images