Plateau pollutant control method for hybrid electric vehicle

Abstract

The invention belongs to the technical field of energy conservation and emission reduction, and discloses a plateau pollutant control method for a hybrid electric vehicle. The method comprises the steps that an oil way correction factor W is set, wherein W = (MAP-A) * (MAP-B) * (MAP-C); wherein MAP-A is oil way pre-control of a plain, the vertical coordinate of the MAP-A is the rotating speed r / min of an engine, and the horizontal coordinate of the MAP-A is the air inlet pressure pa; the MAP-B is a first plateau correction factor, the vertical coordinate of the MAP-B is the rotating speed r / min of the engine, and the horizontal coordinate of the MAP-B is the altitude m; the MAP-C is a second plateau correction factor, the vertical coordinate of the MAP-C is the air inlet pressure pa, and the horizontal coordinate of the MAP-C is the altitude m; and calculating the oil path correction factor W and the pre-control oil quantity to obtain the oil quantity matched with the intake air. According to the method, the emission stability of the hybrid power vehicle type is improved, NOx in plateau emission can be effectively restrained, and it is ensured that plateau emission meets the law.

Description

Technical Field

[0001] The invention relates to the technical field, and in particular to a method for controlling plateau pollutants of a hybrid vehicle. Background Art

[0002] With the increasing requirements of regulations, high-altitude type I and type II emissions (RDE) have been included in the national assessment scope, so high-altitude type I and type II emissions need to be compliant. In recent years, there are more and more hybrid models, which also need to ensure high-altitude type I and type II emissions.

[0003] In plateau environments, the back pressure is reduced, the charging efficiency of the whole vehicle will be improved, and the original model of the engine will be smaller. That is, under the same intake pressure, the actual intake volume in plateau environments will increase, resulting in insufficient original oil volume pre-control. In the case of a closed loop, it is very easy to become lean, which can easily lead to excessive NOx. In addition, hybrid models often start and stop. When the engine is started for the first time, if the catalyst is not fully ignited, it will stall. During the subsequent start and normal operation, it is more likely to cause NO x pop up. Summary of the invention

[0004] The purpose of the present invention is to provide a hybrid vehicle plateau pollutant control method to solve the plateau environment, because the back pressure reduction leads to NO x The problem of easily exceeding the standard.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A method for controlling plateau pollutants of a hybrid vehicle, the method comprising the following steps:

[0007] Set the oil circuit correction factor W, W = (MAP-A) × (MAP-B) × (MAP-C); MAP-A is the oil circuit pre-control in the plain, the ordinate of MAP-A is the engine speed r / min, and the abscissa is the intake pressure pa; MAP-B is the first plateau correction factor, the ordinate of MAP-B is the engine speed r / min, and the abscissa is the altitude m; MAP-C is the second plateau correction factor, the ordinate of MAP-C is the intake pressure pa, and the abscissa is the altitude m;

[0008] The oil circuit correction factor W and the pre-controlled oil quantity are calculated to obtain the oil quantity matching the intake air, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

[0009] Preferably, the numerical range of MAP-A is 1±0.05.

[0010] Preferably, the value range of MAP-B is 1 to 1.1.

[0011] Preferably, the value range of MAP-C is 1 to 1.1.

[0012] A method for controlling plateau pollutants of a hybrid vehicle, the method comprising the following steps:

[0013] Set the catalyst decay temperature F when the hybrid vehicle is stationary to Among them, F1 is the heat dissipation rate at different ambient temperatures when the vehicle is stationary, G1 is the correction factor for F at different altitudes, and G2 is the correction factor for F at different vehicle speeds;

[0014] When the engine is stopped, the center temperature of the catalyst is D. During the engine shutdown process, the center temperature of the catalyst is E=DF. When the engine is started, when the center temperature E of the catalyst is less than the threshold, the catalyst ignition control is entered, otherwise the ignition control is not entered, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

[0015] Preferably, the value of G1 is 1 when the altitude is 0, and the value of G1 is greater than 1 when the altitude increases.

[0016] Preferably, G2 is defined as 1 when the vehicle speed is 0, and the value of G2 increases as the vehicle speed increases.

[0017] Preferably, the conditions for the ignition control are: setting the ignition speed K and torque J, J = L×M, where L is the limiting torque, M is the correction coefficient of the limiting torque, and the M value increases with increasing altitude; when the intake volume during engine operation is greater than a threshold value and the center temperature of the catalyst is greater than 350-450°C, exit the ignition control.

[0018] Preferably, the torque J has a value of 5 to 30 NM.

[0019] Preferably, the ignition speed K is set at 1200-1400 r / min.

[0020] Beneficial effects of the invention: The invention improves the emission stability of hybrid vehicles and can effectively curb NO emissions in plateaus. x , ensuring that plateau emissions are in compliance with the law. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0022] Figure 1 This is a flow chart of an engine plateau model correction method of a hybrid vehicle plateau pollutant control method of the present invention;

[0023] Figure 2 It is a flow chart of a method for exhausting temperature during a hybrid shutdown process of a hybrid vehicle plateau pollutant control method of the present invention;

[0024] Figure 3 The present invention is a flow chart of a hybrid vehicle ignition control method of a hybrid vehicle plateau pollutant control method. DETAILED DESCRIPTION

[0025] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0026] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0028] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0030] like Figure 1-3 As shown, the present invention provides a method for controlling plateau pollutants of a hybrid vehicle, the control method comprising the following steps:

[0031] To solve the problem of intake deviation of the engine model caused by plateau factors, the oil circuit correction factor W is set, W = (MAP-A) × (MAP-B) × (MAP-C); it can solve the deviation of the actual vehicle oil circuit pre-control and solve the problem of lean combustion in the open loop process. MAP-A is the oil circuit pre-control of the plain, the ordinate of MAP-A is the engine speed r / min, and the abscissa is the intake pressure pa; the value range of MAP-A is 1 ± 0.05, and the relationship between the intake volume and speed of MAP-A is shown in Table 1.

[0032] Table 1 Relationship between MAP-A intake volume and speed

[0033]

[0034] MAP-B is the first plateau correction factor, the ordinate of MAP-B is the engine speed r / min, and the abscissa is the altitude m; the value range of MAP-B is 1 to 1.1, and the value generally increases with the increase of altitude. The relationship between MAP-B altitude and speed is shown in Table 2.

[0035] Table 2 Relationship between MAP-B altitude and speed

[0036]

[0037] MAP-C is the second plateau correction factor. The ordinate of MAP-C is the intake pressure pa, and the abscissa is the altitude m. The value range of MAP-C is 1 to 1.1. As the altitude increases, the value generally increases. The relationship between MAP-C altitude and intake pressure is shown in Table 3.

[0038] Table 3 Relationship between MAP-C altitude and intake pressure

[0039]

[0040] The oil circuit correction factor W and the pre-controlled oil quantity are calculated to obtain the oil quantity matching the intake air, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

[0041] A method for controlling plateau pollutants of a hybrid vehicle, the method comprising the following steps:

[0042] For hybrid vehicles, which often need to start and stop, in order to ensure the full activity of the catalyst (that is, to maintain a certain temperature above 450°C after successful ignition), it is necessary to establish a temperature decay model for the catalyst during shutdown. Set the catalyst decay temperature F when the hybrid vehicle is stationary to Among them, F1 is the heat dissipation rate at different ambient temperatures when the vehicle is stationary, and the relationship between F1 and ambient temperature is shown in Table 4.

[0043] Table 4 Relationship between F1 and ambient temperature

[0044] Ambient temperature (℃) -30 -15 -7 0 10 20 30 40 F1(℃ / s)

[0045] G1 is a correction factor for F at different altitudes, and G1 takes a value of 1 when the altitude is 0. When the altitude increases, the value of G1 is greater than 1. The relationship between G1 and ambient temperature is shown in Table 5.

[0046] Table 5 Relationship between G1 and ambient temperature

[0047] Altitude (m) 0 500 1000 1500 2000 2500 3000 4000 G1 1

[0048] G2 is the correction factor of F at different vehicle speeds; G2 is defined as 1 when the vehicle speed is 0, and the value of G2 increases with the increase of vehicle speed. The relationship between G2 and vehicle speed is shown in Table 6.

[0049] Table 6 Relationship between G2 and vehicle speed

[0050] Vehicle speed (Km / h) 0 10 20 30 50 70 100 140 G2 1

[0051] When the engine is stopped, the center temperature of the catalyst is D. During the engine shutdown process, the center temperature of the catalyst is E=DF. When the engine is started, when the center temperature E of the catalyst is less than the threshold, the catalyst ignition control is entered, otherwise the ignition control is not entered, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

[0052] The conditions for the ignition control are: setting the ignition speed K and the torque J, wherein the value of K is 1200-1400 r / min. The relationship between k and the water temperature is shown in Table 7.

[0053] Table 7 Relationship between k and water temperature

[0054] Water temperature (℃) -20 -7 0 10 20 30 50 70 Ignition speed K

[0055] J=L×M, where L is the limit torque, M is the correction coefficient of the limit torque, and the value of M increases with the increase of altitude; the value of J is 5 to 30 NM. The relationship between M and altitude is shown in Table 8.

[0056] Table 8 Relationship between M and altitude

[0057] Altitude (m) 0 500 1000 1500 2000 2500 3000 4000 Correction factor M 1

[0058] When the intake air volume during engine operation is greater than the threshold and the catalyst center temperature is greater than 350-450°C, the light-off control is exited. The relationship between P and altitude is shown in Table 9.

[0059] Table 9 Relationship between P and altitude

[0060] Altitude (m) 0 500 1000 1500 2000 2500 3000 4000 Total air intake volume P 1

[0061] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for controlling plateau pollutants of a hybrid vehicle, characterized in that: The control method comprises the following steps: Set the oil circuit correction factor W, W = (MAP-A) × (MAP-B) × (MAP-C); MAP-A is the oil circuit pre-control in the plain, the ordinate of MAP-A is the engine speed r / min, and the abscissa is the intake pressure pa; MAP-B is the first plateau correction factor, the ordinate of MAP-B is the engine speed r / min, and the abscissa is the altitude m; MAP-C is the second plateau correction factor, the ordinate of MAP-C is the intake pressure pa, and the abscissa is the altitude m; The oil circuit correction factor W and the pre-controlled oil quantity are calculated to obtain the oil quantity matching the intake air, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

2. A hybrid vehicle plateau pollutant control method according to claim 1, characterized in that: The numerical range of MAP-A is 1±0.

05.

3. A hybrid vehicle plateau pollutant control method according to claim 1, characterized in that: The numerical range of MAP-B is 1 to 1.

1.

4. A method for controlling plateau pollutants of a hybrid vehicle according to claim 1, characterized in that: The numerical range of MAP-C is 1 to 1.

1.

5. A method for controlling plateau pollutants of a hybrid vehicle, characterized in that: The control method comprises the following steps: Set the catalyst decay temperature F when the hybrid vehicle is stationary to Among them, F1 is the heat dissipation rate at different ambient temperatures when the vehicle is stationary, G1 is the correction factor for F at different altitudes, and G2 is the correction factor for F at different vehicle speeds; When the engine is stopped, the center temperature of the catalyst is D. During the engine shutdown process, the center temperature of the catalyst is E=DF. When the engine is started, when the center temperature E of the catalyst is less than the threshold, the catalyst ignition control is entered, otherwise the ignition control is not entered, thereby realizing a method for controlling plateau pollutants of a hybrid vehicle.

6. A method for controlling plateau pollutants of a hybrid vehicle according to claim 5, characterized in that: The value of G1 is 1 when the altitude is 0, and the value of G1 is greater than 1 when the altitude increases.

7. A method for controlling plateau pollutants of a hybrid vehicle according to claim 5, characterized in that: The G2 is defined as 1 when the vehicle speed is 0, and the value of G2 increases as the vehicle speed increases.

8. A method for controlling plateau pollutants of a hybrid vehicle according to claim 5, characterized in that: The conditions for the ignition control are: setting the ignition speed K and torque J, J=L×M, where L is the limit torque, M is the correction coefficient of the limit torque, and the M value increases with increasing altitude; when the intake volume during engine operation is greater than the threshold and the center temperature of the catalyst is greater than 350-450°C, exit the ignition control.

9. A method for controlling plateau pollutants of a hybrid vehicle according to claim 8, characterized in that: The torque J has a value of 5 to 30 NM.

10. A method for controlling plateau pollutants of a hybrid vehicle according to claim 8, characterized in that: The ignition speed K is set at 1200-1400 r / min.

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