A mixing valve opening control method, device, equipment and medium

Abstract

The present invention discloses a method, device, equipment, and medium for controlling the opening of a mixing valve. The method includes: when the mixing valve is in a transitional operating state from fully open to partially open, obtaining the current mixing valve opening and the mixing valve opening change rate; determining the maximum boost pressure, minimum boost pressure, current target boost pressure, and current actual boost pressure, and determining a mixing valve opening change rate correction coefficient and a lock time based on the maximum boost pressure, minimum boost pressure, current target boost pressure, and current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged; after the lock time expires, correcting the mixing valve opening change rate based on the mixing valve opening change rate correction coefficient to obtain a final mixing valve opening change rate; and determining the mixing valve control opening based on the current mixing valve opening and the final mixing valve opening change rate. The present invention optimizes the control of the mixing valve opening change rate from the perspective of improving the boost pressure control accuracy.

Description

Technical Field

[0001] The present invention belongs to the technical field of engine control, and in particular relates to a mixing valve opening control method, device, equipment and medium for improving boost pressure control accuracy. Background Art

[0002] Exhaust Gas Recirculation (EGR) extracts exhaust gas from the exhaust and re-enters the intake system. Research has shown that EGR systems offer advantages in improving emissions, reducing fuel consumption, and improving anti-knock performance. In low-pressure EGR systems, optimizing the control of the mixing valve is particularly effective in improving EGR.

[0003] For example, the patent with application number CN202011247319.6 discloses a method and system for calculating the target EGR rate, which determines the basic target EGR rate based on the engine speed and load; obtains the corresponding correction rate based on special working conditions; determines the initial target EGR rate based on the basic target EGR rate and each correction rate; determines whether EGR is activated based on the EGR activation state conditions; divides the EGR state according to the judgment result, and determines the final target EGR rate. This patent calculates the initial target EGR rate from the throttle opening, manifold pressure difference and minimum ignition angle, can accurately calculate the target EGR rate, and introduces EGR control activation conditions to perform secondary corrections on the final target EGR rate. However, this patent does not take into account the control accuracy of the target opening of the mixing valve.

[0004] Therefore, it is necessary to consider the control accuracy when the mixing valve changes from fully open to partially open, optimize the mixing valve opening rate, and improve the control stability. Summary of the Invention

[0005] In response to the above defects or improvement needs of the prior art, the present invention provides a mixing valve opening control method, device, equipment and medium for improving the boost pressure control accuracy, and solves the control stability problem of the mixing valve in the process from fully open to partially open.

[0006] To achieve the above object, according to a first aspect of the present invention, a method for controlling the opening of a mixing valve for improving boost pressure control accuracy is provided. The method comprises:

[0007] When the mixing valve is in a transitional operating state from fully open to partially open, the current mixing valve opening and the mixing valve opening change rate are obtained;

[0008] determining a maximum boost pressure, a minimum boost pressure, a current target boost pressure, and a current actual boost pressure, and determining a mixing valve opening rate change correction coefficient and a lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged;

[0009] After the lock time ends, the mixing valve opening change rate is corrected based on the mixing valve opening change rate correction coefficient to obtain a final mixing valve opening change rate;

[0010] The mixing valve control opening is determined based on the current mixing valve opening and the final mixing valve opening change rate.

[0011] In the above scheme, the mixing valve opening rate change correction coefficient and the lock time are determined based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure, including:

[0012] If the ratio of the current target boost pressure to the maximum boost pressure is greater than a first preset value, the lock time is calibrated according to the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, and the mixing valve opening change rate correction coefficient is set to 1;

[0013] If the ratio of the current target boost pressure to the minimum boost pressure is less than the second preset value, the lock time is set to 0, and the mixing valve opening change rate correction coefficient is set to a third preset value;

[0014] In other cases, the lock time is set to 0, and the mixing valve opening rate change correction coefficient is determined based on the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, the ratio of the current target boost pressure to the maximum boost pressure, and the ratio of the current target boost pressure to the minimum boost pressure.

[0015] In the above scheme, the lock time is calibrated according to the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, including:

[0016] After calibration, ensure that the difference between the target boost pressure and the actual boost pressure after the mixing valve exits full opening is within the preset range, and that the fluctuation range of the target boost pressure and the actual boost pressure is within the preset range;

[0017] Among them, the first preset value is 0.95, the second preset value is 1.02, and the third preset value is 1.15.

[0018] In the above scheme, the mixing valve opening change rate correction coefficient is determined based on the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, the ratio of the current target boost pressure to the maximum boost pressure, and the ratio of the current target boost pressure to the minimum boost pressure, including:

[0019]

[0020] Among them, r2 is the correction coefficient of the mixing valve opening rate change rate, The ratio of the current actual boost pressure to the current target boost pressure and the correction factor determined by the engine speed n, The ratio of the current target boost pressure to the maximum boost pressure Determine the correction factor, The ratio of the current target boost pressure to the minimum boost pressure Determine the correction factor.

[0021] In the above scheme, the method for determining each correction coefficient in the calculation formula of the mixing valve opening change rate correction coefficient is as follows:

[0022] The ratio of the current target boost pressure to the maximum boost pressure at different engine speeds n Not greater than 0.5, the ratio of the current target boost pressure to the minimum boost pressure When it is not less than 1.2, the ratio of the current actual boost pressure to the current target boost pressure is adjusted. Get the correction factor Ensure that the continuous time during which the difference between the target boost pressure and the actual boost pressure in the transition process from fully open to partially open of the mixing valve is within the preset range does not exceed a first preset time;

[0023] At the same time, the fluctuation of engine speed n and the ratio of current actual boost pressure to current target boost pressure When the fluctuations do not exceed the respective preset fluctuation ranges, the mixing valve opening change rate correction coefficient r2 is not updated;

[0024] In determining the correction factor Then, different engine speeds n are fixed, and the ratio of the current target boost pressure to the maximum boost pressure is tested. Greater than 0.5 and not greater than 0.95, the ratio of the current target boost pressure to the minimum boost pressure When it is not less than 1.2, adjust the ratio of the current target boost pressure to the maximum boost pressure To determine the correction factor Similarly, it is ensured that the continuous time during which the difference between the target boost pressure and the actual boost pressure in the transition process from fully open to partially open of the mixing valve is within the preset range does not exceed a first preset time;

[0025] In determining the correction factor and correction factor Then, different engine speeds n are fixed, and the ratio of the current target boost pressure to the maximum boost pressure is tested. Not greater than 0.5, the ratio of the current target boost pressure to the minimum boost pressure When it is less than 1.2 and not less than 1.02, adjust the ratio of the current target boost pressure to the minimum boost pressure To determine the correction factor This also ensures that the continuous time during which the difference between the target boost pressure and the actual boost pressure is within the preset range during the transition from fully open to partially open mixing valve does not exceed the first preset time.

[0026] In the above scheme, the mixing valve opening rate of change is corrected based on the mixing valve opening rate of change correction coefficient to obtain the final mixing valve opening rate of change, including:

[0027] dpct MGVNew =dpct MGVRaw ×r2×(1+r Adapt )

[0028] Among them, dpct MGVNew is the final mixing valve opening change rate, dpct MGVRaw is the mixing valve opening change rate, r2 is the mixing valve opening change rate correction coefficient, r Adapt is the learning update coefficient.

[0029] In the above scheme, the activation conditions for learning the update coefficients include:

[0030] The mixing valve is in the transition process from fully open to partially open;

[0031] The supercharger is in the closed-loop control active state;

[0032] The absolute value of the engine target intake pressure change rate does not exceed the preset change rate value;

[0033] The engine mileage corresponding to the learning update coefficient not being updated exceeds the preset mileage value;

[0034] When the above conditions are met at the same time, the activation condition of the learning update coefficient is met, and the learning update coefficient is updated at this time.

[0035] In the above scheme, the update method of the learning update coefficient includes:

[0036] In the first case, if:

[0037] The difference between the target boost pressure and the actual boost pressure exceeds a preset first difference value for a continuous period exceeding a second preset time;

[0038] The difference between the target EGR rate and the actual EGR rate does not exceed a first preset difference range;

[0039] The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range;

[0040] dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference;

[0041] Then: r Adapt =rAdapt (z)-0.1; where r Adapt (z) is the learning update coefficient obtained from the last learning;

[0042] In the second case, if:

[0043] The difference between the target boost pressure and the actual boost pressure does not exceed a preset first difference value for a continuous period exceeding a second preset time;

[0044] The difference between the target EGR rate and the actual EGR rate does not exceed a first preset difference range;

[0045] The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range;

[0046] dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference;

[0047] Then: r Adapt =r Adapt (z)+0.08;

[0048] The third case, if:

[0049] The difference between the target boost pressure and the actual boost pressure exceeds a preset first difference value for a continuous period exceeding a second preset time;

[0050] The difference between the target EGR rate and the actual EGR rate exceeds the first preset difference range for a continuous period exceeding the second preset time;

[0051] The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range;

[0052] dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference;

[0053] Then: r Adapt =r Adapt (z)-0.03;

[0054] The fourth case, if:

[0055] The difference between the target boost pressure and the actual boost pressure does not exceed a preset first difference value for a continuous period exceeding a second preset time;

[0056] The difference between the target EGR rate and the actual EGR rate exceeds the first preset difference range for a continuous period exceeding the second preset time;

[0057] The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range;

[0058] dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference;

[0059] Then: r Adapt =r Adapt (z)+0.02;

[0060] In other cases, r Adapt =r Adapt (z);

[0061] If the learning update coefficient has been updated once in this driving cycle, the learning update coefficient will not be updated again in this driving cycle.

[0062] According to a second aspect of the present invention, there is provided a mixing valve opening control device for improving boost pressure control accuracy, comprising:

[0063] an acquisition unit, configured to acquire the current mixing valve opening and the mixing valve opening change rate when the mixing valve is in a transitional operating state from fully open to partially open;

[0064] an intermediate unit for determining a maximum boost pressure, a minimum boost pressure, a current target boost pressure, and a current actual boost pressure, and determining a mixing valve opening rate change correction coefficient and a lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged;

[0065] a correction unit, configured to correct the mixing valve opening change rate based on the mixing valve opening change rate correction coefficient after the locking time ends, to obtain a final mixing valve opening change rate;

[0066] The determining unit is configured to determine the control opening of the mixing valve based on the current mixing valve opening and the final mixing valve opening change rate.

[0067] According to a third aspect of the present invention, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the mixing valve opening control method for improving the boost pressure control accuracy as described above are implemented.

[0068] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the steps of the mixing valve opening control method for improving the boost pressure control accuracy as described above are implemented.

[0069] In general, the above technical solutions conceived by the present invention can achieve the following beneficial effects compared with the prior art:

[0070] The present invention determines the mixing valve change rate correction coefficient and the locking time based on the boost pressure limit, the target boost pressure and the actual boost pressure difference. After the locking time ends, the mixing valve opening change rate is corrected based on the mixing valve opening change rate correction coefficient, and the mixing valve opening change rate is controlled and optimized from the perspective of improving the boost pressure control accuracy.

[0071] In addition, when determining the final rate of change of the mixing valve opening, a learning update coefficient is introduced. Through the self-learning update of the learning update coefficient, the boost pressure responsiveness can be improved, the intake pressure responsiveness overshoot can be avoided, the boost pressure responsiveness can be avoided to be too poor or too aggressive, and the control stability of the mixing valve in the process from fully open to partially open can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A flow chart of a mixing valve opening control method for improving boost pressure control accuracy provided by an embodiment of the present invention;

[0073] Figure 2 A schematic structural diagram of a low-pressure EGR system provided in an embodiment of the present invention;

[0074] Figure 3 A flow chart for determining a mixing valve opening rate change correction coefficient and a locking time provided by an embodiment of the present invention;

[0075] Figure 4 A schematic diagram of a mixing valve opening control device for improving boost pressure control accuracy provided by an embodiment of the present invention;

[0076] Figure 5 A schematic structural diagram of a computer device provided in an embodiment of the present invention.

[0077] In the figure: 1-air filter, 2-mixing valve, 3-supercharger compressor, 4-throttle, 5-engine, 6-supercharger turbine, 7-catalyst, 8-particulate matter trap, 9-EGR cooler, 10-EGR valve, 11-EGR temperature sensor, 12-EGR differential pressure sensor. DETAILED DESCRIPTION

[0078] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0079] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0080] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0081] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0082] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0083] The present invention optimizes the mixing valve opening change rate from the perspective of control stability during the process of the mixing valve changing from fully open to partially open.

[0084] like Figure 2As shown, the low-pressure EGR system includes: an air filter 1, a mixing valve 2, a supercharger compressor 3, a throttle valve 4, an engine 5, a supercharger turbine 6, a catalyst 7, a particulate matter trap 8, an EGR cooler 9, an EGR valve 10, an EGR temperature sensor 11, and an EGR differential pressure sensor 12.

[0085] The supercharger compressor 3 compresses fresh air for supercharging; the supercharger turbine 6 controls the working efficiency of the turbine by controlling the opening of the supercharger's exhaust bypass valve, thereby achieving different supercharging capabilities; the low-pressure EGR system has the following additional components compared to the non-low-pressure EGR system: an EGR cooler 9, an EGR temperature sensor 11, an EGR valve 10, an EGR pressure difference sensor 12, and a mixing valve 2; the mixing valve 2 is used to adjust the pressure at the outlet of the EGR valve 10, increase the pressure difference at both ends of the EGR valve 10, and increase the EGR rate; the EGR cooler 9 is used to cool the exhaust gas to facilitate increasing the exhaust gas flow rate and reducing the exhaust gas temperature; the EGR valve 10 has a throttling effect to control the exhaust gas flow rate entering the cylinder; the EGR temperature sensor 11 is used to detect the exhaust gas temperature entering the EGR valve; the EGR pressure difference sensor 12 is used to detect the pressure at the EGR inlet and outlet.

[0086] The purpose of the present invention is to propose a method for controlling the opening of a mixing valve that improves the accuracy of boost pressure control, so as to solve problems such as control stability in the process. Patent CN202110184826.8 "Method for determining the target opening of a mixing valve in an EGR system" and patent CN202110184815.X "Method for determining the activation state of a mixing valve in a low-pressure EGR system" both mention transition control in the process of the mixing valve changing from fully open (non-activated state) to non-fully open (activated), and determine the rate of change of the target opening of the mixing valve and the shortest time for the mixing valve to be non-fully open. The present invention optimizes the rate of change of the target opening of the mixing valve when the mixing valve requests to enter the non-fully open process, so as to further improve the control stability problem in the control process.

[0087] like Figure 1 As shown, the mixing valve opening control method for improving boost pressure control accuracy according to an embodiment of the present invention includes the following steps:

[0088] S1. When the mixing valve is in a transitional operating state from fully open to partially open, obtain the current mixing valve opening and the mixing valve opening change rate.

[0089] Assume that based on the current public technology, the current mixing valve is in a transition state from fully open to partially open, and the current mixing valve opening is pct MGVRaw , and the rate of change is dpct MGVRaw .

[0090] S2. Determine the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure, and determine the mixing valve opening rate change correction coefficient and the lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged.

[0091] Based on the maximum boost pressure, the minimum boost pressure (the description of the maximum boost pressure and the minimum boost pressure can be found in patent CN202311487573.7 "A boost pressure control method") and the current target boost pressure (the target boost pressure can be found in patent CN202010109549.X "Method for determining target boost pressure of an exhaust gas turbocharger engine, storage medium"), and the actual boost pressure, the mixing valve opening change rate correction coefficient r2 and the locking time t1 are determined, where the locking time t1 refers to the time to maintain the current mixing valve opening unchanged (of course, the mixing valve opening rate change correction coefficient that affects the change of the mixing valve opening in other cases still works). After the locking time t1 ends, the mixing valve opening rate is corrected based on the mixing valve opening rate change correction coefficient r2.

[0092] like Figure 3 The specific steps are as follows:

[0093] S201, the ratio of the current target boost pressure to the maximum boost pressure When it is greater than the preset value, which is 0.95 in this example, the lock time t1 depends on At the same time, the mixing valve target opening rate change correction coefficient r2 is set to 1 to meet the boost pressure requirements, achieve boost control stability, and meet the vehicle dynamics requirements. BoostAct is the actual boost pressure.

[0094] The calibration method is: 1) ensure that the difference between the target boost pressure and the actual boost pressure is controlled within ±2kPa, 2) at the same time, when the target boost pressure fluctuation range is within ±2kPa, the actual boost pressure fluctuation range is also within ±2kPa.

[0095] S202, the ratio of the current target boost pressure to the minimum boost pressure When it is less than the preset value, which is 1.02 in this example, the locking time t1 is 0, and the correction coefficient r2 of the target opening rate of the mixing valve is set to 1.15, so as to quickly reduce the boost pressure and improve the vehicle dynamics.

[0096] S203. In other cases, t1 is equal to 0, and:

[0097]

[0098] in, Based on and the correction factor determined by the engine speed n, Based on Determine the correction factor, Based on Determine the correction factor.

[0099] In the pressure ratio The smaller the value, the slower the boost pressure control response. In order to improve the boost pressure control accuracy, it is necessary to reduce the mixing valve opening change rate, thereby increasing the gas flow entering the supercharger compressor, improving the boost capacity, and thus increasing the actual boost pressure. If it is too large, it means that the boost pressure control response is too fast. In order to improve the boost pressure control accuracy, the mixing valve opening change rate is increased to reduce the gas flow entering the supercharger compressor as quickly as possible, reduce the boost capacity, and thus reduce the actual boost pressure. In this example, at different engine speeds n, Not more than 0.5, When it is not less than 1.2, adjust the pressure ratio Get Ensure that during the transition from fully open to partially open mixing valve, the difference between the target boost pressure and the actual boost pressure is controlled within ±2kPa for no more than 0.5s.

[0100] Likewise, to avoid the engine speed n and Too frequent fluctuations lead to If the adjustment changes too much, which causes the correction coefficient r2 to change too much and the mixing valve opening control fluctuates too much, resulting in poor mixing valve control stability, the following treatment should be performed:

[0101] The engine speed fluctuation n (the difference between the engine speed in this sampling period and the engine speed in the previous sampling period, the sampling period in this example is 10ms) does not exceed the preset value (in this example, ±40rpm) and Fluctuation (pressure ratio in this sampling period The pressure ratio compared with the previous sampling period When the sampling period (10ms in this example) does not exceed the preset value (±0.15 in this example), the correction coefficient r2 is not updated.

[0102] After calibration Then, fix different engine speed n, and test Greater than 0.5 and not greater than 0.95, When it is not less than 1.2, adjust to determine Similarly, it is ensured that during the transition from fully open to partially open mixing valve, the difference between the target boost pressure and the actual boost pressure is controlled within ±2kPa for no more than 0.5s.

[0103] After calibration and Then, fix different engine speed n, and test Not more than 0.5, When it is less than 1.2 and not less than 1.02, adjust to determine Similarly, it is ensured that during the transition from fully open to partially open mixing valve, the difference between the target boost pressure and the actual boost pressure is controlled within ±2kPa for no more than 0.5s.

[0104] S3. After the locking time ends, the mixing valve opening change rate is corrected based on the mixing valve opening change rate correction coefficient to obtain a final mixing valve opening change rate.

[0105] In the transition process from fully open to partially open, the final mixing valve opening change rate dpct MGVNew :

[0106] dpct MGVNew =dpct MGVRaw ×r2×(1+r Adapt )

[0107] Among them, r Adapt To learn the update coefficient, its default value is 0 and can be saved after the vehicle is powered off.

[0108] To improve the boost pressure responsiveness and EGR rate response accuracy during control, the update method can only be activated when the following conditions are met simultaneously:

[0109] (1) The mixing valve is in the transition process from fully open to partially open;

[0110] (2) The supercharger is in the closed-loop control active state;

[0111] (3) The absolute value of the engine target intake pressure change rate does not exceed the preset value, which is 2 kPa / 10 ms in this example;

[0112] (4) The engine mileage corresponding to the learning coefficient not being updated exceeds the preset value, which is 20,000 kilometers in this example.

[0113] When all of the above conditions are met, then:

[0114] In the first case, the boost pressure response is poor, but the EGR rate response is good:

[0115] 1) The difference between the target boost pressure and the actual boost pressure exceeds the preset value (in this example, 5kPa) for a continuous period of more than 0.1s

[0116] 2) The difference between the target EGR rate and the actual EGR rate does not exceed the preset value ±0.1;

[0117] 3) The difference between the target mixing valve opening and the actual mixing valve opening shall not exceed the preset value (in this example, ±1%);

[0118] 4)dpct MGVNew -dpct MGVRaw The value does not exceed the preset value. In this example, it is -15% / 10ms.

[0119] Improve boost pressure responsiveness:

[0120] r Adapt =r Adapt (z)-0.1, where r Adapt (z) is the self-learning correction coefficient obtained from the last learning.

[0121] In the second case, the boost pressure response is too aggressive, but the EGR rate response is good:

[0122] 1) The difference between the target boost pressure and the actual boost pressure is less than the preset value. In this example, the continuous time of -5kPa exceeds 0.1s.

[0123] 2) The difference between the target EGR rate and the actual EGR rate does not exceed the preset value ±0.1;

[0124] 3) The difference between the target mixing valve opening and the actual mixing valve opening shall not exceed the preset value (in this example, ±1%);

[0125] 4)dpct MGVNew -dpct MGVRaw The value does not exceed the preset value. In this example, it is -15% / 10ms.

[0126] To avoid severe overshoot of intake pressure response:

[0127] r Adapt =r Adapt (z)+0.08.

[0128] In the third case, the boost pressure responsiveness is poor and the EGR rate responsiveness is poor:

[0129] 1) The difference between the target boost pressure and the actual boost pressure is greater than the preset value (5 kPa in this example) for more than 0.1 seconds;

[0130] 2) The difference between the target EGR rate and the actual EGR rate exceeds the preset value ±0.15 for more than 0.1s continuously;

[0131] 3) The difference between the target mixing valve opening and the actual mixing valve opening shall not exceed the preset value (in this example, ±1%);

[0132] 4)dpct MGVNew -dpct MGVRaw The value does not exceed the preset value. In this example, it is -15% / 10ms.

[0133] Then properly adjust the mixing valve full opening rate to avoid poor boost pressure responsiveness:

[0134] r Adapt =r Adapt (z)-0.03.

[0135] In the fourth case, the boost pressure response is too aggressive, but the EGR rate response is poor:

[0136] 1) The difference between the target boost pressure and the actual boost pressure is less than the preset value (in this example, -5 kPa) for more than 0.1 seconds;

[0137] 2) The difference between the target EGR rate and the actual EGR rate exceeds the preset value ±0.15 for more than 0.1s continuously;

[0138] 3) The difference between the target mixing valve opening and the actual mixing valve opening shall not exceed the preset value (in this example, ±1%);

[0139] 4)dpct MGVNew -dpct MGVRaw The value does not exceed the preset value. In this example, it is -15% / 10ms.

[0140] Then appropriately adjust the mixing valve full opening rate to avoid overly aggressive boost pressure response:

[0141] r Adapt =r Adapt (z)+0.02

[0142] In other cases, r Adapt =r Adapt (z).

[0143] If the learning coefficient is updated, it will not be updated in this driving cycle.

[0144] S4. Determine the mixing valve control opening based on the current mixing valve opening and the final mixing valve opening change rate.

[0145] Finally, the action behavior of the mixing valve is determined based on the target opening of the mixing valve and the optimized opening change rate of the mixing valve.

[0146] The above completes the entire description of the control method of the mixing valve from fully open to partially open.

[0147] The mixing valve opening control device for improving the boost pressure control accuracy based on the above embodiment is as follows: Figure 4 As shown, including:

[0148] The acquisition unit 501 is used to acquire the current mixing valve opening and the mixing valve opening change rate when the mixing valve is in a transitional operating state from fully open to partially open;

[0149] The intermediate unit 502 is configured to determine the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure, and determine the mixing valve opening rate change rate correction coefficient and the lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged;

[0150] A correction unit 503 is configured to correct the mixing valve opening rate of change based on the mixing valve opening rate of change correction coefficient after the locking time expires to obtain a final mixing valve opening rate of change;

[0151] The determining unit 504 is configured to determine the control opening of the mixing valve based on the current mixing valve opening and the final mixing valve opening change rate.

[0152] like Figure 5 The figure shows a schematic diagram of the structure of a computer device provided by an embodiment of the present invention, such as a smart phone, tablet computer, laptop computer, desktop computer, rack server, blade server, tower server or cabinet server (including a standalone server or a server cluster composed of multiple servers), etc. The computer device 20 of this embodiment includes at least but not limited to: a memory 21 and a processor 22 that can be interconnected via a system bus, such as Figure 5 It should be pointed out that Figure 5 Computer device 20 is shown only with components 21 - 22 , but it should be understood that implementing all of the illustrated components is not a requirement, and greater or fewer components may alternatively be implemented.

[0153] In this embodiment, the memory 21 (i.e., a readable storage medium) includes flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory), random access memory (RAM), static random access memory (SRAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and programmable read-only memory (PROM). The memory 21 may also be an external storage device of the computer device 20, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash memory card, etc. equipped on the computer device 20. Of course, the memory 21 may also include both the internal storage unit of the computer device 20 and its external storage device. In this embodiment, the memory 21 is generally used to store the operating system and various application software installed on the computer device 20, such as the program code of the mixing valve opening control method for improving boost pressure control accuracy in the method embodiment. In addition, the memory 21 may also be used to temporarily store various data that has been output or is about to be output.

[0154] In some embodiments, the processor 22 may be a central processing unit (CPU), a controller, a microcontroller, a microprocessor, or other data processing chip. The processor 22 is generally used to control the overall operation of the computer device 20. In this embodiment, the processor 22 is used to execute program code stored in the memory 21 or process data. For example, the processor 22 executes a device storing program code for a mixing valve opening control method for improving boost pressure control accuracy to implement the mixing valve opening control method for improving boost pressure control accuracy described in the method embodiment.

[0155] The present application also provides a computer-readable storage medium, such as a flash memory, a hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a disk, an optical disk, a server, an App application store, etc., on which a computer program is stored, and when the program is executed by a processor, a corresponding function is implemented. The computer-readable storage medium of this embodiment is used to store program code of a mixing valve opening control method for improving boost pressure control accuracy, and when executed by a processor, implements the mixing valve opening control method for improving boost pressure control accuracy of the method embodiment.

[0156] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0157] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0158] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0159] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0160] In summary, the present invention proposes a mixing valve opening control method, device, equipment and medium for improving the boost pressure control accuracy. The method determines the mixing valve change rate correction coefficient and locking time based on the boost pressure limit, the target boost pressure and the actual boost pressure difference. After the locking time ends, the mixing valve opening change rate is corrected based on the mixing valve opening change rate correction coefficient, and the mixing valve opening change rate is controlled and optimized from the perspective of improving the boost pressure control accuracy.

[0161] It should be noted that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0162] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, or two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0163] It will be easily understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for controlling the opening of a mixing valve to improve the control accuracy of boost pressure, characterized in that: The method includes: When the mixing valve is in a transitional operating state from fully open to partially open, the current mixing valve opening and the mixing valve opening change rate are obtained; determining a maximum boost pressure, a minimum boost pressure, a current target boost pressure, and a current actual boost pressure, and determining a mixing valve opening rate change correction coefficient and a lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged; After the lock time ends, the mixing valve opening change rate is corrected based on the mixing valve opening change rate correction coefficient to obtain a final mixing valve opening change rate; The mixing valve control opening is determined based on the current mixing valve opening and the final mixing valve opening change rate.

2. The mixing valve opening control method for improving boost pressure control accuracy according to claim 1, characterized in that: The mixing valve opening rate change correction coefficient and the lock time are determined based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure, including: If the ratio of the current target boost pressure to the maximum boost pressure is greater than a first preset value, the lock time is calibrated according to the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, and the mixing valve opening change rate correction coefficient is set to 1; If the ratio of the current target boost pressure to the minimum boost pressure is less than the second preset value, the lock time is set to 0, and the mixing valve opening change rate correction coefficient is set to a third preset value; In other cases, the lock time is set to 0, and the mixing valve opening rate change correction coefficient is determined based on the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, the ratio of the current target boost pressure to the maximum boost pressure, and the ratio of the current target boost pressure to the minimum boost pressure.

3. The mixing valve opening control method for improving boost pressure control accuracy according to claim 2, characterized in that: The lock time is calibrated based on the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, including: After calibration, ensure that the difference between the target boost pressure and the actual boost pressure after the mixing valve exits full opening is within the preset range, and at the same time, the fluctuation range of the target boost pressure and the actual boost pressure is within the preset range.

4. The mixing valve opening control method for improving boost pressure control accuracy according to claim 2, characterized in that: The first preset value is 0.95, the second preset value is 1.02, and the third preset value is 1.

15.

5. The mixing valve opening control method for improving boost pressure control accuracy according to claim 2, characterized in that: The mixing valve opening change rate correction coefficient is determined based on the ratio of the current actual boost pressure to the current target boost pressure and the engine speed, the ratio of the current target boost pressure to the maximum boost pressure, and the ratio of the current target boost pressure to the minimum boost pressure, including: Among them, r2 is the correction coefficient of the mixing valve opening rate change rate, The ratio of the current actual boost pressure to the current target boost pressure and the correction factor determined by the engine speed n, The ratio of the current target boost pressure to the maximum boost pressure Determine the correction factor, The ratio of the current target boost pressure to the minimum boost pressure Determine the correction factor.

6. The mixing valve opening control method for improving boost pressure control accuracy according to claim 5, characterized in that: The method for determining each correction coefficient in the calculation formula of the mixing valve opening change rate correction coefficient is as follows: The ratio of the current target boost pressure to the maximum boost pressure at different engine speeds n Not greater than 0.5, the ratio of the current target boost pressure to the minimum boost pressure When it is not less than 1.2, the ratio of the current actual boost pressure to the current target boost pressure is adjusted. Get the correction factor Ensure that the continuous time during which the difference between the target boost pressure and the actual boost pressure in the transition process from fully open to partially open of the mixing valve is within the preset range does not exceed a first preset time; At the same time, the fluctuation of engine speed n and the ratio of current actual boost pressure to current target boost pressure When the fluctuations do not exceed the respective preset fluctuation ranges, the mixing valve opening change rate correction coefficient r2 is not updated; In determining the correction factor Then, different engine speeds n are fixed, and the ratio of the current target boost pressure to the maximum boost pressure is tested. Greater than 0.5 and not greater than 0.95, the ratio of the current target boost pressure to the minimum boost pressure When it is not less than 1.2, adjust the ratio of the current target boost pressure to the maximum boost pressure To determine the correction factor Similarly, it is ensured that the continuous time during which the difference between the target boost pressure and the actual boost pressure in the transition process from fully open to partially open of the mixing valve is within the preset range does not exceed a first preset time; In determining the correction factor and correction factor Then, different engine speeds n are fixed, and the ratio of the current target boost pressure to the maximum boost pressure is tested. Not greater than 0.5, the ratio of the current target boost pressure to the minimum boost pressure When it is less than 1.2 and not less than 1.02, adjust the ratio of the current target boost pressure to the minimum boost pressure To determine the correction factor This also ensures that the continuous time during which the difference between the target boost pressure and the actual boost pressure is within the preset range during the transition from fully open to partially open mixing valve does not exceed the first preset time.

7. The mixing valve opening control method for improving boost pressure control accuracy according to claim 1, characterized in that: The mixing valve opening rate of change is corrected based on the mixing valve opening rate of change correction coefficient to obtain a final mixing valve opening rate of change, including: dpct MGVNew =dpct MGVRaw ×r2×(1+r Adapt ) Among them, dpct MGVNew is the final mixing valve opening change rate, dpct MGVRaw is the mixing valve opening change rate, r2 is the mixing valve opening change rate correction coefficient, r Adapt is the learning update coefficient.

8. The method for controlling the opening of a mixing valve to improve the boost pressure control accuracy according to claim 7, characterized in that: The activation conditions for learning update coefficients include: The mixing valve is in the transition process from fully open to partially open; The supercharger is in the closed-loop control active state; The absolute value of the engine target intake pressure change rate does not exceed the preset change rate value; The engine mileage corresponding to the learning update coefficient not being updated exceeds the preset mileage value; When the above conditions are met at the same time, the activation condition of the learning update coefficient is met, and the learning update coefficient is updated at this time.

9. The method for controlling the opening of a mixing valve to improve the boost pressure control accuracy according to claim 7, wherein: The update methods for learning update coefficients include: In the first case, if: The difference between the target boost pressure and the actual boost pressure exceeds a preset first difference value for a continuous period exceeding a second preset time; The difference between the target EGR rate and the actual EGR rate does not exceed a first preset difference range; The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range; dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference; Then: r Adapt =r Adapt (z)-0.1; where r Adapt (z) is the learning update coefficient obtained from the last learning; In the second case, if: The difference between the target boost pressure and the actual boost pressure does not exceed a preset first difference value for a continuous period exceeding a second preset time; The difference between the target EGR rate and the actual EGR rate does not exceed a first preset difference range; The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range; dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference; Then: r Adapt =r Adapt (z)+0.08; The third case, if: The difference between the target boost pressure and the actual boost pressure exceeds a preset first difference value for a continuous period exceeding a second preset time; The difference between the target EGR rate and the actual EGR rate exceeds the first preset difference range for a continuous period exceeding the second preset time; The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range; dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference; Then: r Adapt =r Adapt (z)-0.03; The fourth case, if: The difference between the target boost pressure and the actual boost pressure does not exceed a preset first difference value for a continuous period exceeding a second preset time; The difference between the target EGR rate and the actual EGR rate exceeds the first preset difference range for a continuous period exceeding the second preset time; The difference between the target mixing valve opening and the actual mixing valve opening does not exceed a second preset difference range; dpct MGVNew -dpct MGVRaw The value of does not exceed the second preset difference; Then: r Adapt =r Adapt (z)+0.02; In other cases, r Adapt =r Adapt (z).

10. The mixing valve opening control method for improving boost pressure control accuracy according to claim 9, characterized in that: If the learning update coefficient has been updated once in this driving cycle, the learning update coefficient will not be updated again in this driving cycle.

11. A mixing valve opening control device for improving boost pressure control accuracy, characterized in that: include: an acquisition unit, configured to acquire the current mixing valve opening and the mixing valve opening change rate when the mixing valve is in a transitional operating state from fully open to partially open; an intermediate unit for determining a maximum boost pressure, a minimum boost pressure, a current target boost pressure, and a current actual boost pressure, and determining a mixing valve opening rate change correction coefficient and a lock time based on the maximum boost pressure, the minimum boost pressure, the current target boost pressure, and the current actual boost pressure; wherein the lock time refers to the time for maintaining the current mixing valve opening unchanged; a correction unit, configured to correct the mixing valve opening change rate based on the mixing valve opening change rate correction coefficient after the locking time ends, to obtain a final mixing valve opening change rate; The determining unit is configured to determine the control opening of the mixing valve based on the current mixing valve opening and the final mixing valve opening change rate.

12. A computer device, characterized in that: It includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the steps of the mixing valve opening control method for improving the boost pressure control accuracy as described in any one of claims 1 to 10 are implemented.

13. A computer-readable storage medium, characterized in that A computer program is stored thereon, and when the computer program is executed by a processor, the steps of the mixing valve opening control method for improving the boost pressure control accuracy as claimed in any one of claims 1 to 10 are implemented.

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