Air inlet control method based on vehicle engine and related device

Abstract

The invention discloses an air inlet control method based on a vehicle engine and a related device, and the method comprises the steps that after the vehicle engine is started, air inlet control is conducted on the vehicle engine according to the valve lift and the valve timing in the normal state; the current environment temperature and the intercooled temperature of the intercooler are obtained; when the temperature after intercooling is smaller than the first condensation temperature and the current environment temperature is smaller than the preset freezing temperature, the valve lift and the valve timing in the normal state are switched into the valve lift and the valve timing in the anti-freezing state; the first condensation temperature is determined by the pre-intercooling temperature, the pre-intercooling humidity and the pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is larger than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; and air inlet control is conducted on the vehicle engine according to the valve lift and the valve timing in the anti-icing state. According to the method, the freezing risk of the intercooler is reduced, and the vehicle driving safety is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to an intake control method and related devices based on a vehicle engine. Background Art

[0002] At present, in order to protect the vehicle engine, extend the oil life, and improve fuel economy, a forced crankcase ventilation system is often used. Usually, the forced crankcase ventilation system is composed of a full-load breathing pipe, a partial-load breathing pipe, an oil-gas separator, and a one-way valve.

[0003] When the intake pressure of the intake manifold connected to the vehicle engine is lower than the ambient pressure, the crankcase mixture is discharged from the partial load breathing pipe, pushing open the one-way valve and entering the intake manifold and the engine; when the intake pressure of the intake manifold is higher than the ambient pressure, the crankcase mixture is discharged from the full load breathing pipe, passing through the compressor, intercooler and throttle, and then entering the intake manifold and the engine.

[0004] However, the crankcase mixture discharged from the full-load breathing pipe is heated up by the compressor and then enters the intercooler for cooling. The crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water and freeze in a low temperature environment; when the intake pressure of the intake manifold is frequently higher than the ambient pressure, the ice gradually increases, affecting the driving safety of the vehicle. Summary of the invention

[0005] In view of this, the embodiment of the present application provides an intake control method and related devices based on a vehicle engine. By judging that the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, it is determined that the crankcase mixture is easily reduced to below the condensing temperature in the intercooler to precipitate condensed water. When freezing occurs in a low temperature environment, the variable valve lift is increased and the valve timing is adjusted later to improve the intake efficiency and intake pressure of the intake manifold, reduce the exhaust frequency of the full-load breathing pipe to reduce the intake humidity, increase the temperature after intercooling, thereby reducing the risk of freezing and improving the driving safety of the vehicle.

[0006] On the one hand, an embodiment of the present application provides an intake control method based on a vehicle engine, the method comprising:

[0007] After the vehicle engine is started, the intake control of the vehicle engine is performed according to the valve lift and valve timing in a normal state;

[0008] Get the current ambient temperature and the intercooler post-intercooler temperature;

[0009] If the post-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state;

[0010] The vehicle engine is controlled to have air intake according to the valve lift and valve timing in the anti-icing state.

[0011] Optionally, the step of determining the first condensation temperature includes:

[0012] determining absolute humidity according to the pre-intercooling temperature, the pre-intercooling humidity and the pre-intercooling pressure;

[0013] The first condensation temperature is calculated according to the absolute humidity.

[0014] Optionally, the method further includes:

[0015] Determine a first proportion of full-load breathing tube air outlet in a preset time period before the normal state is switched to the anti-icing state, and a second proportion of full-load breathing tube air outlet in a preset time period after the normal state is switched to the anti-icing state;

[0016] estimating a second condensation temperature for switching the valve lift and valve timing from the anti-icing state to the valve lift and valve timing in the normal state according to the intake air volume, the blowby gas volume, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine;

[0017] Obtaining the current ambient temperature and the post-intercooling temperature of the intercooler again;

[0018] If the intercooler temperature is greater than the second condensing temperature, or the current ambient temperature is greater than a preset non-icing temperature, the valve lift and valve timing in the anti-icing state are switched to the valve lift and valve timing in the normal state;

[0019] Intake control is performed on the vehicle engine according to the valve lift and valve timing in the normal state.

[0020] Optionally, the temperature after intercooling is greater than the second condensing temperature, specifically, the temperature after intercooling is greater than a preset non-condensing temperature; the preset non-condensing temperature is the sum of the second condensing temperature and a preset residual temperature, and the preset residual temperature is greater than 0°C.

[0021] Optionally, the estimating the second condensation temperature of the valve lift and valve timing switched from the anti-icing state to the normal state according to the intake air volume, the blowby gas volume, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine includes:

[0022] estimating increased humidity according to the intake air amount, the blowby gas amount, the water content, the first proportion, and the second proportion;

[0023] The second condensation temperature is calculated according to the increased humidity and the absolute humidity.

[0024] The optional step of determining the first proportion and the second proportion includes:

[0025] determining the first proportion according to the intake pressure of the intake manifold and the ambient pressure within a preset time period before the normal state is switched to the anti-icing state;

[0026] The second ratio is determined according to the intake pressure of the intake manifold and the ambient pressure within a preset time period after the normal state is switched to the anti-icing state.

[0027] Optionally, the method further includes:

[0028] If the post-intercooling temperature is lower than the second condensing temperature and the current ambient temperature is lower than the preset non-freezing temperature, the intake control of the vehicle engine continues according to the valve lift and valve timing in the anti-icing state.

[0029] On the other hand, an embodiment of the present application provides an intake control device based on a vehicle engine, the device comprising: a control unit, an acquisition unit and a switching unit;

[0030] The control unit is used to control the intake of the vehicle engine according to the valve lift and valve timing in a normal state after the vehicle engine is started;

[0031] The acquisition unit is used to acquire the current ambient temperature and the post-intercooling temperature of the intercooler;

[0032] The switching unit is used to switch the valve lift and valve timing in the normal state to the valve lift and valve timing in the anti-icing state if the post-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset icing temperature; the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state;

[0033] The control unit is also used to control the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state.

[0034] Optionally, the device further includes: a first determining unit;

[0035] The first determining unit is specifically configured to:

[0036] determining absolute humidity according to the pre-intercooling temperature, the pre-intercooling humidity and the pre-intercooling pressure;

[0037] The first condensation temperature is calculated according to the absolute humidity.

[0038] Optionally, the device further comprises: a second determining unit and an estimating unit;

[0039] The second determination unit is used to determine a first proportion of full-load breathing tube air outlet in a preset time period before the normal state is switched to the anti-icing state, and a second proportion of full-load breathing tube air outlet in a preset time period after the normal state is switched to the anti-icing state;

[0040] The estimation unit is used to estimate a second condensation temperature when the valve lift and valve timing are switched from the anti-icing state to the normal state according to the intake air amount, the blowby gas amount, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine;

[0041] The acquisition unit is further used to acquire the current ambient temperature and the post-intercooling temperature of the intercooler again;

[0042] The switching unit is further configured to switch the valve lift and valve timing in the anti-icing state to the valve lift and valve timing in the normal state if the intercooling temperature is greater than the second condensing temperature, or the current ambient temperature is greater than a preset non-icing temperature;

[0043] The control unit is also used to control the intake of the vehicle engine according to the valve lift and valve timing in the normal state.

[0044] Optionally, the temperature after intercooling is greater than the second condensing temperature, specifically, the temperature after intercooling is greater than a preset non-condensing temperature; the preset non-condensing temperature is the sum of the second condensing temperature and a preset residual temperature, and the preset residual temperature is greater than 0°C.

[0045] Optionally, the estimation unit is specifically used for:

[0046] estimating increased humidity according to the intake air amount, the blowby gas amount, the water content, the first proportion, and the second proportion;

[0047] The second condensation temperature is calculated according to the increased humidity and the absolute humidity.

[0048] Optionally, the device further includes: a third determining unit;

[0049] The third determining unit is specifically configured to:

[0050] determining the first proportion according to the intake pressure of the intake manifold and the ambient pressure within a preset time period before the normal state is switched to the anti-icing state;

[0051] The second ratio is determined according to the intake pressure of the intake manifold and the ambient pressure within a preset time period after the normal state is switched to the anti-icing state.

[0052] Optionally, the control unit is further used to:

[0053] If the post-intercooling temperature is lower than the second condensing temperature and the current ambient temperature is lower than the preset non-freezing temperature, the intake control of the vehicle engine continues according to the valve lift and valve timing in the anti-icing state.

[0054] On the other hand, an embodiment of the present application provides a vehicle, the vehicle comprising a processor and a memory:

[0055] The memory is used to store a computer program and transmit the computer program to the processor;

[0056] The processor is configured to execute the method described in the above aspects according to the instructions in the computer program.

[0057] On the other hand, an embodiment of the present application provides a computer-readable storage medium, which is used to store a computer program, and the computer program is executed by a processor to implement the method described in the above aspects.

[0058] Compared with the prior art, this application has at least the following advantages:

[0059] By adopting the technical solution of the embodiment of the present application, first, after the vehicle engine is started, the intake of the vehicle engine is controlled according to the valve lift and valve timing in the normal state; then, the current ambient temperature and the after-intercooling temperature of the intercooler are obtained; when the after-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined by the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; finally, the intake of the vehicle engine is controlled according to the valve lift and valve timing in the anti-icing state. It can be seen that this method determines that the crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water by judging that the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature. When freezing occurs in a low temperature environment, the variable valve lift is increased and the valve timing is adjusted later to improve the intake efficiency and intake pressure of the intake manifold, reduce the exhaust frequency of the full-load breathing pipe to reduce the intake humidity, and increase the temperature after intercooling, thereby reducing the risk of freezing and improving the driving safety of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the description of the embodiments of the present application will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0061] Figure 1 A schematic diagram of a system framework involved in an application scenario in an embodiment of the present application;

[0062] Figure 2 A schematic flow chart of an intake control method based on a vehicle engine provided in an embodiment of the present application;

[0063] Figure 3 A schematic diagram of a valve lift and valve timing in a normal state switched to a valve lift and valve timing in an anti-icing state provided by an embodiment of the present application;

[0064] Figure 4 A comparison diagram of full-load exhaust and part-load exhaust when the valve lift and valve timing in a normal state are switched to the valve lift and valve timing in an anti-icing state provided in an embodiment of the present application;

[0065] Figure 5 A specific flow chart of an intake control method based on a vehicle engine provided in an embodiment of the present application;

[0066] Figure 6 A schematic structural diagram of an air intake control device based on a vehicle engine provided in an embodiment of the present application. DETAILED DESCRIPTION

[0067] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0068] At present, when the intake pressure of the intake manifold connected to the vehicle engine is lower than the ambient pressure, the crankcase mixture is discharged from the partial load breathing pipe, pushes open the one-way valve and enters the intake manifold and the engine; when the intake pressure of the intake manifold is higher than the ambient pressure, the crankcase mixture is discharged from the full load breathing pipe, passes through the compressor, intercooler and throttle, and enters the intake manifold and the engine. However, the crankcase mixture discharged from the full load breathing pipe is heated by the compressor and then enters the intercooler for cooling. The crankcase mixture is easily reduced to below the condensation temperature in the intercooler, condensed water is precipitated, and ice is formed in a low temperature environment; when the intake pressure of the intake manifold is frequently higher than the ambient pressure, ice gradually increases, affecting the driving safety of the vehicle.

[0069] In order to solve this problem, in an embodiment of the present application, first, after the vehicle engine is started, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in a normal state; then, the current ambient temperature and the intercooler post-intercooling temperature of the intercooler are obtained; when the intercooler post-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in an anti-icing state; the first condensing temperature is determined by the intercooler pre-intercooling temperature, the intercooler pre-intercooling humidity and the intercooler pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; finally, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in the anti-icing state. It can be seen that this method determines that the crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water by judging that the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature. When freezing occurs in a low temperature environment, the variable valve lift is increased and the valve timing is adjusted later to improve the intake efficiency and intake pressure of the intake manifold, reduce the exhaust frequency of the full-load breathing pipe to reduce the intake humidity, and increase the temperature after intercooling, thereby reducing the risk of freezing and improving the driving safety of the vehicle.

[0070] For example, one of the scenarios of the embodiment of the present application may be applied to Figure 1 The scene includes an ambient temperature sensor 101, an air filter 102, a compressor 103, a temperature / humidity / pressure sensor before intercooling 104, an intercooler 105, a temperature sensor after intercooling 106, a throttle valve 107, an intake manifold 108, an intake manifold temperature sensor 109, an engine 110, a crankcase 110, an oil-gas separator 112, a partial load breathing pipe 113, a check valve 114, a full load breathing pipe 115, a variable valve timing and variable valve lift system 116, an intake pipe 117, and an intake passage 118.

[0071] The above scenario is only an example scenario provided by the embodiment of the present application, and the embodiment of the present application is not limited to this scenario.

[0072] The specific implementation of the intake control method and related devices based on the vehicle engine in the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0073] First, the specific implementation of the intake control method based on the vehicle engine in the embodiment of the present application is described in detail through an embodiment.

[0074] See also Figure 2 , shows a flow chart of an intake control method based on a vehicle engine in an embodiment of the present application. In this embodiment, the method may include the following steps:

[0075] S201: After the vehicle engine is started, the intake of the vehicle engine is controlled according to the valve lift and valve timing in a normal state.

[0076] In an embodiment of the present application, after the vehicle engine is started, the valve lift and valve timing need to be considered in order to control the intake of the vehicle engine; based on this, first, the intake of the vehicle engine is controlled according to the valve lift and valve timing under normal conditions.

[0077] S202: Acquire the current ambient temperature and the post-intercooling temperature of the intercooler.

[0078] S203: If the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined based on the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state.

[0079] When the intake pressure of the intake manifold connected to the vehicle engine is lower than the ambient pressure, the crankcase mixture is discharged from the partial load breathing pipe, pushes open the one-way valve and enters the intake manifold and the engine; when the intake pressure of the intake manifold is higher than the ambient pressure, the crankcase mixture is discharged from the full load breathing pipe, passes through the compressor, intercooler and throttle, and then enters the intake manifold and the engine. The crankcase mixture discharged from the full load breathing pipe is heated by the compressor and then enters the intercooler for cooling. The crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water and freeze in a low temperature environment; when the intake pressure of the intake manifold is frequently higher than the ambient pressure, the ice gradually increases, affecting the driving safety of the vehicle.

[0080] Therefore, in an embodiment of the present application, in order to solve the above-mentioned problem, when executing the above-mentioned S201 and controlling the intake of the vehicle engine according to the valve lift and valve timing in a normal state, it is necessary to obtain the current ambient temperature and the temperature after the intercooler of the intercooler, and judge whether the crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water and freeze in a low temperature environment based on whether the temperature after the intercooler is lower than the first condensing temperature and whether the current ambient temperature is lower than the preset freezing temperature; if so, switch the valve lift and valve timing in a normal state to a larger valve lift and a later valve timing, that is, the valve lift and valve timing in an anti-icing state, so as to reduce the intake pressure, improve the intake efficiency of the intake manifold, reduce the exhaust frequency of the full-load breathing pipe, reduce the intake humidity, and increase the temperature after the intercooler, thereby reducing the risk of freezing.

[0081] Based on this, the current ambient temperature and the post-intercooling temperature of the intercooler are obtained. When the post-intercooling temperature is less than the first condensing temperature and the current ambient temperature is less than the preset freezing temperature, it means that the crankcase mixture is easily reduced to below the first condensing temperature in the intercooler to precipitate condensed water and freeze at the current ambient temperature. At this time, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state. Among them, the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state.

[0082] As an example, in Figure 1On the basis of this, the current ambient temperature T2 is measured by the ambient temperature sensor 101, the post-intercooler temperature T3 of the intercooler 105 is measured by the post-intercooler temperature sensor 106, and the pre-intercooler temperature T1, pre-intercooler humidity H1, and pre-intercooler pressure P1 of the intercooler 105 are measured by the pre-intercooler temperature / humidity / pressure sensor 104; the first condensation temperature Tc is determined based on T1, H1, and P1; the preset icing temperature is 0 °C. If T3 < Tc and T2 < 0 °C, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state. Refer to Figure 3 , which shows a schematic diagram of switching the valve lift and valve timing in the normal state to the valve lift and valve timing in the anti-icing state in an embodiment of the present application. Among them, the valve lift in the normal state is 145, the valve lift in the anti-icing state is 175, and the valve timing in the normal state is earlier than the valve timing in the anti-icing state.

[0083] S204: Perform intake control on the vehicle engine according to the valve lift and valve timing in the anti-icing state.

[0084] In an embodiment of the present application, after performing the above S202 - S203 to switch the valve lift and valve timing in the normal state to the valve lift and valve timing in the anti-icing state, in order to improve the intake efficiency and intake pressure of the intake manifold, reduce the outlet frequency of the full-load breather pipe, so as to reduce the intake humidity, increase the post-intercooler temperature, and thus reduce the icing risk, it is also necessary to perform intake control on the vehicle engine according to the valve lift and valve timing in the anti-icing state.

[0085] Since the valve lift in the anti-icing state is greater than the valve lift in the normal state, performing intake control on the vehicle engine according to the valve lift in the anti-icing state reduces the intake pressure of the intake manifold, thereby improving the intake efficiency of the intake manifold; at the same time, since the valve timing in the anti-icing state is later than the valve timing in the normal state, performing intake control on the vehicle engine according to the valve timing in the anti-icing state adjusts the combustion cycle from the Miller cycle towards the Otto cycle, further improving the intake efficiency of the intake manifold. After the intake efficiency of the intake manifold is improved, the intake air volume required to output the same torque decreases, that is, the intake pressure of the intake manifold decreases; based on this, the crankcase mixture is discharged more frequently from the part-load breather pipe, reducing the outlet frequency of the full-load breather pipe, so as to reduce the intake humidity, increase the post-intercooler temperature, and thus reduce the icing risk.

[0086] Refer to Figure 4, shows a comparison diagram of full-load exhaust and part-load exhaust when the valve lift and valve timing in a normal state are switched to the valve lift and valve timing in an anti-icing state in an embodiment of the present application; wherein, the vehicle engine is controlled for intake according to the valve lift and valve timing in the normal state, and is adjusted to control the vehicle engine for intake according to the valve lift and valve timing in the anti-icing state, the exhaust frequency of the full-load breathing pipe is reduced, that is, the exhaust area of ​​the full-load breathing pipe is reduced, and the exhaust frequency of the part-load breathing pipe is increased, that is, the exhaust area of ​​the part-load breathing is expanded.

[0087] Through the various implementation methods provided by this embodiment, first, after the vehicle engine is started, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in a normal state; then, the current ambient temperature and the intercooler temperature after intercooling are obtained; when the intercooler temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined by the intercooler temperature before intercooling, the intercooler humidity before intercooling and the intercooler pressure before intercooling, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; finally, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in the anti-icing state. It can be seen that this method determines that the crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water by judging that the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature. When freezing occurs in a low temperature environment, the variable valve lift is increased and the valve timing is adjusted later to improve the intake efficiency and intake pressure of the intake manifold, reduce the exhaust frequency of the full-load breathing pipe to reduce the intake humidity, and increase the temperature after intercooling, thereby reducing the risk of freezing and improving the driving safety of the vehicle.

[0088] In the embodiment of the present application, the first condensing temperature is actually determined by first determining the absolute humidity of the intercooler through the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler; and then calculating the first condensing temperature of the intercooler through the absolute humidity. Therefore, in an optional implementation of the embodiment of the present application, the step of determining the first condensing temperature includes the following S1-S2:

[0089] S1: Determine the absolute humidity based on the temperature before intercooling, the humidity before intercooling and the pressure before intercooling.

[0090] S2: Calculate the first condensation temperature according to the absolute humidity.

[0091] As an example, based on the above example, the absolute humidity is determined to be AH1 based on the pre-intercooling temperature T1, the pre-intercooling humidity H1 and the pre-intercooling pressure P1; and the first condensing temperature is calculated to be Tc based on AH1.

[0092] In addition, in an embodiment of the present application, when it is determined that the crankcase mixture is easily lowered to below the condensing temperature in the intercooler to precipitate condensed water and freeze in a low temperature environment, the valve lift and valve timing in a normal state are switched to the valve lift and valve timing in an anti-icing state, and after the vehicle engine is controlled to have an intake air according to the valve lift and valve timing in the anti-icing state, considering that the crankcase mixture may not be lowered to below the condensing temperature in the intercooler to precipitate condensed water after a period of time, or may not freeze in a higher temperature environment, at this time, in order to further protect the vehicle engine, extend the life of the engine oil, and improve fuel economy, it is also necessary to switch the valve lift and valve timing in the anti-icing state to the valve lift and valve timing in the normal state, and control the intake air of the vehicle engine according to the valve lift and valve timing in the normal state.

[0093] Based on this, firstly, determine the first proportion of full-load breathing pipe outlet air in a preset time period before the normal state switches to the anti-icing state, and the second proportion of full-load breathing pipe outlet air in a preset time period after the normal state switches to the anti-icing state; so as to estimate the second condensation temperature when the valve lift and valve timing are switched from the anti-icing state to the valve lift and valve timing in the normal state through the intake volume, blowby volume, water content, first proportion, second proportion and absolute humidity of the vehicle engine; then, determine the current ambient temperature and the post-intercooling temperature of the intercooler again to determine whether the post-intercooling temperature is greater than the second condensation temperature. If so, it means that the crankcase mixture may not be reduced to below the condensation temperature in the intercooler to precipitate condensed water, or, whether the current ambient temperature is greater than the preset non-icing temperature. If so, it means that it will not freeze in a higher temperature environment; based on this, switch the valve lift and valve timing in the anti-icing state to the valve lift and valve timing in the normal state, and control the intake of the vehicle engine according to the valve lift and valve timing in the normal state. Therefore, in an optional implementation manner of the embodiment of the present application, the method further includes the following S3-S7:

[0094] S3: Determine a first proportion of full-load breathing tube air outlet in a preset time period before the normal state is switched to the anti-icing state, and a second proportion of full-load breathing tube air outlet in a preset time period after the normal state is switched to the anti-icing state.

[0095] Among them, when S3 is specifically implemented, it is considered that when the intake pressure of the intake manifold connected to the vehicle engine is lower than the ambient pressure, the crankcase mixture is discharged from the partial load breathing pipe, pushing open the one-way valve to enter the intake manifold and the engine; when the intake pressure of the intake manifold is higher than the ambient pressure, the crankcase mixture is discharged from the full load breathing pipe, passes through the compressor, intercooler and throttle, and enters the intake manifold and the engine; therefore, the first proportion of the full load breathing pipe outlet in the preset time period before the normal state switches to the anti-icing state is actually determined by the intake pressure and ambient pressure of the intake manifold in the preset time period before the normal state switches to the anti-icing state; the second proportion of the full load breathing pipe outlet in the preset time period after the normal state switches to the anti-icing state is actually determined by the intake pressure and ambient pressure of the intake manifold in the preset time period after the normal state switches to the anti-icing state. That is, in an optional implementation of the embodiment of the present application, S3 includes the following S3a-S3b:

[0096] S3a: Determine a first ratio according to the intake pressure of the intake manifold and the ambient pressure within a preset time period before switching from the normal state to the anti-icing state.

[0097] S3b: Determine a second ratio according to the intake pressure of the intake manifold and the ambient pressure within a preset time period after the normal state is switched to the anti-icing state.

[0098] If the preset time period is not reached after the normal state is switched to the anti-icing state, the second proportion is determined according to the intake pressure of the intake manifold and the ambient pressure in the actual time period after the normal state is switched to the anti-icing state.

[0099] As an example, the preset time period is 1 minute, the intake pressure is Psr, and the ambient pressure is Pu; Figure 1 On this basis, the first proportion of the air outlet of the full-load breathing tube 112 1 minute before the normal state is switched to the anti-icing state is determined to be N1% through the Psr and Pu of the intake manifold 108 within 1 minute before the normal state is switched to the anti-icing state; the second proportion of the air outlet of the full-load breathing tube 112 1 minute after the normal state is switched to the anti-icing state is determined to be N2% through the Psr and Pu of the intake manifold 108 within 1 minute after the normal state is switched to the anti-icing state (if it does not reach 1 minute after the normal state is switched to the anti-icing state, the actual time period after the normal state is switched to the anti-icing state is taken).

[0100] S4: estimating a second condensation temperature when the valve lift and valve timing are switched from the anti-icing state to the normal state according to the intake air volume, the blowby gas volume, the water content, the first ratio, the second ratio and the absolute humidity of the vehicle engine.

[0101] Among them, when S4 is specifically implemented, first, the increased humidity can be estimated through the intake volume, blowby volume, water content, first proportion, and second proportion of the vehicle engine; then, on the basis of absolute moderation, the absolute humidity of the intercooler when the valve lift and valve timing in the anti-icing state are switched to the valve lift and valve timing in the normal state is obtained in combination with the increased humidity to calculate the second condensing temperature of the intercooler. Therefore, in an optional implementation of the embodiment of the present application, S4 includes the following S4a-S4b:

[0102] S4a: Estimate the added humidity based on the intake air volume, blowby gas volume, water content, first proportion, and second proportion.

[0103] S4b: Calculate the second condensation temperature according to the increased humidity and the absolute humidity.

[0104] As an example, through the intake volume ml, blowby volume L, water content AH2, first proportion N1% and second proportion N2% of the vehicle engine, it can be estimated that the increased humidity is L / ml×AH2×(N1%-N2%); through the absolute humidity AH1 and L / ml×AH2×(N1%-N2%), the absolute humidity of the intercooler when the valve lift and valve timing are switched from the anti-icing state to the normal state is calculated to be AHc=L / ml×AH2×(N1%-N2%)+AH1; the second condensing temperature of the intercooler is calculated to be Tc'.

[0105] S5: Obtain the current ambient temperature and the post-intercooling temperature of the intercooler again.

[0106] S6: If the temperature after the intercooler is greater than the second condensing temperature, or the current ambient temperature is greater than the preset non-freezing temperature, the valve lift and valve timing in the anti-freezing state are switched to the valve lift and valve timing in the normal state.

[0107] Among them, in order to further ensure that the crankcase mixture may not be lowered to below the condensation temperature in the intercooler to precipitate condensed water, the judgment of whether the temperature after intercooling is greater than the second condensation temperature can be optimized to judge whether the temperature after intercooling is greater than the preset non-condensation temperature higher than the second condensation temperature. If so, it more accurately indicates that the crankcase mixture will not be lowered to below the condensation temperature in the intercooler to precipitate condensed water; based on this, a preset margin temperature is configured, and the temperature of the second condensation temperature and the preset margin temperature are used as the preset non-condensation temperature, so that when judging whether the temperature after intercooling is greater than the second condensation temperature, it can be optimized to judge whether the temperature after intercooling is greater than the preset non-condensation temperature. Therefore, in an optional implementation of the embodiment of the present application, the temperature after intercooling is greater than the second condensation temperature specifically means that the temperature after intercooling is greater than the preset non-condensation temperature, the preset non-condensation temperature is the sum of the second condensation temperature and the preset margin temperature, and the preset margin temperature is greater than 0°C.

[0108] As an example, the preset non-freezing temperature is 5°C. Based on the above example, the current ambient temperature is T2 and the intercooler's intercooler temperature is T3; if T3>Tc' or T2>5°C, the valve lift and valve timing in the anti-icing state are switched to the valve lift and valve timing in the normal state.

[0109] S7: Control the intake of the vehicle engine according to the valve lift and valve timing in a normal state.

[0110] In addition, after executing S3-S5, there may be a situation where the temperature after the intercooler is less than the second condensing temperature and the current ambient temperature is less than the preset non-freezing temperature, indicating that the crankcase mixture is still easily reduced to below the condensing temperature in the intercooler to precipitate condensed water and freeze in a low temperature environment; in this case, it is necessary to continue to control the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state, improve the intake efficiency and intake pressure of the intake manifold, and reduce the exhaust frequency of the full-load breathing tube to reduce the intake humidity, increase the temperature after the intercooler, and thus reduce the risk of icing. Therefore, in an optional implementation of the embodiment of the present application, after executing S3-S5, the method also includes S8: if the temperature after the intercooler is less than the second condensing temperature and the current ambient temperature is less than the preset non-freezing temperature, continue to control the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state.

[0111] Based on the above description, see Figure 5, shows a specific flow chart of an intake control method based on a vehicle engine in an embodiment of the present application, the specific flow refers to: after the vehicle engine is started, the intake of the vehicle engine is controlled according to the valve lift and valve timing in a normal state; according to the pre-intercooling temperature T1, the pre-intercooling humidity H1 and the pre-intercooling pressure P1, the first condensation temperature Tc is determined, and the current ambient temperature T2 and the post-intercooling temperature T3 of the intercooler are obtained; it is judged that T3<Tc and T2<0℃, if so, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state, if not, return to the step of controlling the intake of the vehicle engine according to the valve lift and valve timing in the normal state. According to the valve lift and valve timing in the anti-icing state, the vehicle engine is controlled for intake; according to the intake volume ml, the blowby volume L, the water content AH2, the first proportion N1% of the full-load breathing pipe outlet in the preset time period before the normal state is switched to the anti-icing state, and the second proportion N2% of the full-load breathing pipe outlet in the preset time period after the normal state is switched to the anti-icing state, the second condensation temperature Tc' when the valve lift and valve timing are switched from the anti-icing state to the valve lift and valve timing in the normal state is estimated, and the current ambient temperature T2 and the intercooling temperature T3 of the intercooler are obtained again; it is judged that T3>Tc' or T2>5℃, if so, the valve lift and valve timing in the anti-icing state are switched to the valve lift and valve timing in the normal state, and the step of controlling the intake of the vehicle engine according to the valve lift and valve timing in the normal state is returned; if not, the step of controlling the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state is returned.

[0112] Next, the specific implementation of the intake control device based on the vehicle engine in the embodiment of the present application is described in detail through an embodiment.

[0113] See also Figure 6 , shows a schematic diagram of the structure of an intake control device based on a vehicle engine in an embodiment of the present application. In this embodiment, the device may specifically include: a control unit 601, an acquisition unit 602 and a switching unit 603;

[0114] A control unit 601 is used to control the intake of the vehicle engine according to the valve lift and valve timing in a normal state after the vehicle engine is started;

[0115] An acquisition unit 602 is used to acquire the current ambient temperature and the post-intercooling temperature of the intercooler;

[0116] The switching unit 603 is used to switch the valve lift and valve timing in the normal state to the valve lift and valve timing in the anti-icing state if the temperature after the intercooling is less than the first condensing temperature and the current ambient temperature is less than the preset icing temperature; the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state;

[0117] The control unit 601 is also used to control the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state.

[0118] In an optional implementation of the embodiment of the present application, the device further includes: a first determining unit;

[0119] The first determining unit is specifically used for:

[0120] Determine the absolute humidity based on the temperature before intercooling, the humidity before intercooling, and the pressure before intercooling;

[0121] The first condensation temperature is calculated based on the absolute humidity.

[0122] In an optional implementation of the embodiment of the present application, the device further includes: a second determination unit and an estimation unit;

[0123] A second determining unit is used to determine a first proportion of full-load breathing tube air outlet in a preset time period before the normal state is switched to the anti-icing state, and a second proportion of full-load breathing tube air outlet in a preset time period after the normal state is switched to the anti-icing state;

[0124] an estimating unit, for estimating a second condensing temperature of the valve lift and valve timing when switching from the valve lift and valve timing in the anti-icing state to the valve lift and valve timing in the normal state according to the intake air volume, the blowby gas volume, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine during operation;

[0125] The acquisition unit 602 is further used to acquire the current ambient temperature and the post-intercooling temperature of the intercooler again;

[0126] The switching unit 603 is further used to switch the valve lift and valve timing in the anti-icing state to the valve lift and valve timing in the normal state if the temperature after the intercooling is greater than the second condensing temperature, or the current ambient temperature is greater than the preset non-icing temperature;

[0127] The control unit 601 is also used to control the intake of the vehicle engine according to the valve lift and valve timing in a normal state.

[0128] In an optional implementation of the embodiment of the present application, the temperature after intercooling is greater than the second condensing temperature, specifically, the temperature after intercooling is greater than the preset non-condensing temperature; the preset non-condensing temperature is the sum of the second condensing temperature and the preset residual temperature, and the preset residual temperature is greater than 0°C.

[0129] In an optional implementation of the embodiment of the present application, the estimation unit is specifically configured to:

[0130] Estimate the added humidity based on the intake volume, blowby volume, water content, first proportion, and second proportion;

[0131] Based on the added humidity and the absolute humidity, the second condensation temperature is calculated.

[0132] In an optional implementation of the embodiment of the present application, the apparatus further includes: a third determining unit;

[0133] The third determining unit is specifically configured to:

[0134] Determining a first ratio according to the intake pressure of the intake manifold and the ambient pressure within a preset time period before switching from the normal state to the anti-icing state;

[0135] The second ratio is determined according to the intake pressure of the intake manifold and the ambient pressure within a preset time period after the normal state is switched to the anti-icing state.

[0136] In an optional implementation of the embodiment of the present application, the control unit 601 is further configured to:

[0137] If the temperature after the intercooler is lower than the second condensing temperature and the current ambient temperature is lower than the preset non-freezing temperature, the intake of the vehicle engine continues to be controlled according to the valve lift and valve timing in the anti-icing state.

[0138] Through the various implementation methods provided by this embodiment, first, after the vehicle engine is started, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in a normal state; then, the current ambient temperature and the intercooler temperature after intercooling are obtained; when the intercooler temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined by the intercooler temperature before intercooling, the intercooler humidity before intercooling and the intercooler pressure before intercooling, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; finally, the vehicle engine is controlled to have air intake according to the valve lift and valve timing in the anti-icing state. It can be seen that the device determines that the crankcase mixture is easily reduced to below the condensation temperature in the intercooler to precipitate condensed water by judging that the temperature after intercooling is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature. When freezing occurs in a low temperature environment, the device increases the variable valve lift and adjusts the valve timing later to improve the intake efficiency and intake pressure of the intake manifold, reduces the exhaust frequency of the full-load breathing pipe to reduce the intake humidity, and increases the temperature after intercooling, thereby reducing the risk of freezing and improving the driving safety of the vehicle.

[0139] In addition, an embodiment of the present application further provides a vehicle, the vehicle including a processor and a memory:

[0140] The memory is used to store the computer program and transmit the computer program to the processor;

[0141] The processor is configured to execute the method of the above embodiment according to the instructions in the computer program.

[0142] The embodiments of the present application also provide a computer-readable storage medium, which is used to store a computer program, and the computer program is used to implement the method of the above embodiment.

[0143] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0144] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0145] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "include", "comprises" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprises a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0146] The above is only a preferred embodiment of the present application and does not constitute any formal limitation to the present application. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any technician familiar with the art can make many possible changes and modifications to the technical solution of the present application using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present application, or modify it into an equivalent embodiment of equivalent changes. Therefore, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present application without departing from the content of the technical solution of the present application still fall within the scope of protection of the technical solution of the present application.

Claims

1. An intake control method based on a vehicle engine, characterized in that: include: After the vehicle engine is started, the intake control of the vehicle engine is performed according to the valve lift and valve timing in a normal state; Get the current ambient temperature and the intercooler post-intercooler temperature; If the post-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset freezing temperature, the valve lift and valve timing in the normal state are switched to the valve lift and valve timing in the anti-icing state; the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; The vehicle engine is controlled to have air intake according to the valve lift and valve timing in the anti-icing state.

2. The method according to claim 1, characterized in that The step of determining the first condensation temperature comprises: determining absolute humidity according to the pre-intercooling temperature, the pre-intercooling humidity and the pre-intercooling pressure; The first condensation temperature is calculated according to the absolute humidity.

3. The method according to claim 2, characterized in that The method further comprises: Determine a first proportion of full-load breathing tube air outlet in a preset time period before the normal state is switched to the anti-icing state, and a second proportion of full-load breathing tube air outlet in a preset time period after the normal state is switched to the anti-icing state; estimating a second condensation temperature for switching the valve lift and valve timing from the anti-icing state to the valve lift and valve timing in the normal state according to the intake air volume, the blowby gas volume, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine; Obtaining the current ambient temperature and the post-intercooling temperature of the intercooler again; If the intercooler temperature is greater than the second condensing temperature, or the current ambient temperature is greater than a preset non-icing temperature, the valve lift and valve timing in the anti-icing state are switched to the valve lift and valve timing in the normal state; Intake control is performed on the vehicle engine according to the valve lift and valve timing in the normal state.

4. The method according to claim 3, characterized in that Specifically, the temperature after intercooling is greater than the second condensing temperature, which means that the temperature after intercooling is greater than a preset non-condensing temperature; the preset non-condensing temperature is the sum of the second condensing temperature and a preset residual temperature, and the preset residual temperature is greater than 0°C.

5. The method according to claim 3, characterized in that: The estimating, based on the intake air volume, the blowby gas volume, the water content, the first proportion, the second proportion and the absolute humidity of the vehicle engine, the second condensation temperature when the valve lift and valve timing are switched from the anti-icing state to the valve lift and valve timing in the normal state includes: estimating increased humidity according to the intake air amount, the blowby gas amount, the water content, the first proportion, and the second proportion; The second condensation temperature is calculated according to the increased humidity and the absolute humidity.

6. The method according to claim 3, characterized in that The steps of determining the first proportion and the second proportion include: determining the first proportion according to the intake pressure of the intake manifold and the ambient pressure within a preset time period before the normal state is switched to the anti-icing state; The second ratio is determined according to the intake pressure of the intake manifold and the ambient pressure within a preset time period after the normal state is switched to the anti-icing state.

7. The method according to claim 3, characterized in that The method further comprises: If the post-intercooling temperature is lower than the second condensing temperature and the current ambient temperature is lower than the preset non-freezing temperature, the intake control of the vehicle engine continues according to the valve lift and valve timing in the anti-icing state.

8. An air intake control device based on a vehicle engine, characterized in that: include: A control unit, an acquisition unit and a switching unit; The control unit is used to control the intake of the vehicle engine according to the valve lift and valve timing in a normal state after the vehicle engine is started; The acquisition unit is used to acquire the current ambient temperature and the post-intercooling temperature of the intercooler; The switching unit is used to switch the valve lift and valve timing in the normal state to the valve lift and valve timing in the anti-icing state if the post-intercooling temperature is lower than the first condensing temperature and the current ambient temperature is lower than the preset icing temperature; the first condensing temperature is determined according to the pre-intercooling temperature, pre-intercooling humidity and pre-intercooling pressure of the intercooler, the valve lift in the anti-icing state is greater than the valve lift in the normal state, and the valve timing in the anti-icing state is later than the valve timing in the normal state; The control unit is also used to control the intake of the vehicle engine according to the valve lift and valve timing in the anti-icing state.

9. A vehicle, characterized in that: The vehicle comprises a processor and a memory: The memory is used to store a computer program and transmit the computer program to the processor; The processor is configured to execute the method according to any one of claims 1 to 7 according to the instructions in the computer program.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program, and when the computer program is executed by a processor, it is used to implement the method according to any one of claims 1 to 7.

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