Control method and control device for a variable nozzle ring supercharger
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DONGFENG COMML VEHICLE CO LTD
- Filing Date
- 2023-10-18
- Publication Date
- 2026-05-29
Smart Images
Figure CN117231353B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of engine technology, specifically to a control method and control device for a variable nozzle ring turbocharger. Background Technology
[0002] Currently, VGT (Variable Geometry Turbocharger) turbochargers are characterized by their wide adaptability and strong adjustment capability, and can be set with different boost pressures according to different operating conditions.
[0003] In related technologies, the turbocharger turbine inlet pressure model, i.e., the exhaust manifold pressure model, is used as the basic condition for turbocharger position output. However, when the turbocharger system is aging or component measurements are drifting, the problems of turbocharger overspeed and limited turbocharger capacity also exist. Summary of the Invention
[0004] This application provides a control method and control device for a variable nozzle ring turbocharger, which can solve the technical problems of turbocharger overspeed and turbocharger capacity limitation when the turbocharger system fails in the prior art.
[0005] In a first aspect, embodiments of this application provide a control method for a variable nozzle ring intensifier, the control method for the variable nozzle ring intensifier comprising:
[0006] Obtain the measured value and the pressure model value of the exhaust manifold pressure, and take the difference between the two as the first difference value. The pressure model value is obtained based on the exhaust manifold pressure model.
[0007] When the first difference exceeds the first preset deviation range, the measured value of the intake manifold pressure is obtained, and the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure is obtained as the second difference.
[0008] If the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range, then the position of the booster nozzle ring is controlled according to the first difference.
[0009] If the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range, then the position of the booster nozzle ring is controlled according to the pressure model value.
[0010] In conjunction with the first aspect, in one embodiment, controlling the position of the turbocharger nozzle ring based on the aforementioned first difference specifically includes:
[0011] Based on the first difference mentioned above, obtain the correction value for the nozzle ring position;
[0012] The nozzle ring position is adjusted based on the aforementioned correction value.
[0013] In conjunction with the first aspect, in one embodiment, when the first difference does not exceed the first preset deviation range or the second difference does not exceed the second preset deviation range, the position of the turbocharger nozzle ring is controlled based on the measured value of the exhaust manifold pressure.
[0014] In conjunction with the first aspect, in one embodiment, after obtaining the first difference, the method further includes comparing the first difference with a first preset deviation range.
[0015] Before comparing the first difference with the first preset deviation range, the method further includes:
[0016] Based on the pre-stored pulse spectrum of the first deviation range between rotational speed and atmospheric pressure, the first deviation range of the current rotational speed and atmospheric pressure is obtained.
[0017] In conjunction with the first aspect, in one embodiment, after obtaining the second difference, the method further includes comparing the second difference with a second preset deviation range;
[0018] Before comparing the second difference with the second preset deviation range, the process also includes:
[0019] Based on the pre-stored pulse spectrum of the second deviation range between rotational speed and atmospheric pressure, the second deviation range under the current rotational speed and atmospheric pressure is obtained.
[0020] In conjunction with the first aspect, in one embodiment, before obtaining the measured value of the exhaust manifold pressure and the pressure model value, the method further includes:
[0021] Determine whether the diagnostic criteria for the reasonableness of the exhaust manifold pressure are met; if so, it indicates that both the measured value and the pressure model value of the exhaust manifold pressure are reasonable.
[0022] In conjunction with the first aspect, in one embodiment, the above-mentioned exhaust manifold pressure rationality diagnostic conditions include:
[0023] The engine speed is within the preset speed range;
[0024] The throttle opening is greater than the preset opening;
[0025] The ambient temperature is within the preset temperature range, or the engine coolant temperature is greater than or equal to the temperature threshold.
[0026] Atmospheric pressure is within the preset pressure range;
[0027] The exhaust manifold pressure sensor, intake manifold pressure sensor, and exhaust manifold pressure model are all functioning correctly.
[0028] In conjunction with the first aspect, in one embodiment, when the ambient temperature is less than the lower limit of a preset temperature range, the engine coolant temperature is lower than a temperature threshold, and the exhaust manifold pressure model is fault-free, the position of the turbocharger nozzle ring is controlled according to the pressure model value.
[0029] Secondly, embodiments of this application provide a control device for a variable nozzle ring intensifier that implements the above-described control method. The control device for the variable nozzle ring intensifier includes:
[0030] The first acquisition module is used to acquire the measured value of the exhaust manifold pressure and the pressure model value, and to acquire the difference between the two as the first difference.
[0031] The second acquisition module is used to acquire the measured value of the intake manifold pressure when the first difference exceeds the first preset deviation range, and to acquire the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure as the second difference.
[0032] The control module is configured to control the position of the booster nozzle ring based on the first difference when the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range; and to control the position of the booster nozzle ring based on the pressure model value when the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range.
[0033] In conjunction with the second aspect, in one embodiment, the control module is further configured to control the position of the turbocharger nozzle ring based on the measured value of the exhaust manifold pressure when the first difference does not exceed the first preset deviation range or the second difference does not exceed the second preset deviation range.
[0034] The beneficial effects of the technical solutions provided in this application include at least the following:
[0035] By acquiring the measured value of exhaust manifold pressure and the pressure model value, and obtaining the difference between the two as the first difference, and then when the first difference exceeds the first preset deviation range, acquiring the measured value of intake manifold pressure, and obtaining the difference between the measured value of exhaust manifold pressure and the measured value of intake manifold pressure as the second difference; at this time, if the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the first difference; if the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the pressure model value. This solves the technical problems of turbocharger overspeed and turbocharger capacity limitation when the turbocharger system fails in related technologies, ensuring the safety and responsiveness of the engine. Attached Figure Description
[0036] Figure 1 This is a schematic flowchart of an embodiment of the control method for the variable nozzle ring booster of this application;
[0037] Figure 2 This is a schematic flowchart of another embodiment of the control method for the variable nozzle ring booster of this application. Detailed Implementation
[0038] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.
[0039] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.
[0040] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.
[0041] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.
[0042] In a first aspect, embodiments of this application provide a control method for a variable nozzle ring booster.
[0043] like Figure 1 As shown, a control method for a variable nozzle ring intensifier includes:
[0044] S1. Obtain the measured value and the pressure model value of the exhaust manifold pressure, and obtain the difference between the two as the first difference value. The pressure model value is obtained based on the exhaust manifold pressure model.
[0045] S2. When the first difference exceeds the first preset deviation range, the measured value of the intake manifold pressure is obtained, and the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure is obtained as the second difference.
[0046] S3. If the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range, then the position of the booster nozzle ring is controlled according to the first difference.
[0047] S4. If the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range, then the position of the booster nozzle ring is controlled according to the pressure model value.
[0048] In this embodiment, the measured value of exhaust manifold pressure and the pressure model value are obtained, and the difference between the two is taken as the first difference. Then, when the first difference exceeds the first preset deviation range, the measured value of intake manifold pressure is obtained, and the difference between the measured value of exhaust manifold pressure and the measured value of intake manifold pressure is taken as the second difference. At this time, if the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the first difference. If the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the pressure model value. This solves the technical problems of turbocharger overspeed and turbocharger capacity limitation when the turbocharger system fails in related technologies, ensuring the safety and responsiveness of the engine, and ensuring that the engine and actuator operate within the safe boundary range, without causing over-temperature, over-pressure, or over-emission control problems due to erroneous actuator control.
[0049] Furthermore, in one embodiment, step S3 above, controlling the position of the turbocharger nozzle ring based on the first difference, specifically includes:
[0050] First, based on the first difference mentioned above, obtain the correction value for the nozzle ring position;
[0051] Then, the nozzle ring position is adjusted according to the above correction value.
[0052] In this embodiment, the nozzle ring position is corrected based on the difference between the measured exhaust manifold pressure and the pressure model value. That is, a correction is made based on the actual exhaust manifold pressure and the nozzle ring position. By combining the measured exhaust manifold pressure value, the position of the turbocharger nozzle ring is limited to ensure that the turbocharger operates within a safe pressure range and to prevent high-cycle fatigue caused by excessive exhaust manifold pressure.
[0053] Optionally, when the first difference between the measured value of the exhaust manifold pressure and the pressure model value is greater than the upper limit of the first preset deviation range, and the second difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure is greater than the upper limit of the second preset deviation range, the nozzle ring position is corrected according to the first difference by looking up a preset correction pulse table. If the nozzle ring position is 50% at this time and the table correction value is -5%, then the nozzle ring position is controlled to 45%.
[0054] Furthermore, in one embodiment, when the first difference does not exceed the first preset deviation range or the second difference does not exceed the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the measured value of the exhaust manifold pressure.
[0055] In this embodiment, when the first difference does not exceed the first preset deviation range, it indicates that the engine is in normal control state, and there is no need to obtain the measured value of the intake manifold pressure, and therefore there is no need to calculate the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure.
[0056] In this embodiment, when the first difference exceeds the first preset deviation range, but the second difference does not exceed the second preset deviation range, it still indicates that the engine is in normal control state.
[0057] When the engine is in normal control mode, the measured value of the exhaust manifold pressure is used for control. At this time, the turbocharger position is controlled according to the opening degree of the opening model and is corrected according to the closed-loop control state.
[0058] Therefore, when the first difference exceeds the first preset deviation range, the difference between the measured values of the exhaust manifold pressure and the intake manifold pressure is calculated. When the second difference is within the second preset deviation range, it is considered that the overspeed risk of the turbocharger is controllable, and the normal logic control state is maintained. When the second difference exceeds the second preset deviation range, it is considered that the turbocharger will be restricted or overspeed, and the air system control can be performed according to the specific situation using the measured value or the open-loop value of EGR (Exhaust Gas Recirculation) obtained from the model value.
[0059] Based on the above embodiments, in this embodiment, after obtaining the first difference, the method further includes comparing the first difference with a first preset deviation range.
[0060] Furthermore, before comparing the aforementioned first difference with the first preset deviation range, the method further includes:
[0061] Based on the pre-stored pulse spectrum of the first deviation range between rotational speed and atmospheric pressure, the first deviation range of the current rotational speed and atmospheric pressure is obtained.
[0062] Furthermore, after obtaining the second difference, the method also includes comparing the second difference with a second preset deviation range.
[0063] In this embodiment, before comparing the second difference with the second preset deviation range, the method further includes:
[0064] Based on the pre-stored pulse spectrum of the second deviation range between rotational speed and atmospheric pressure, the second deviation range under the current rotational speed and atmospheric pressure is obtained.
[0065] Optionally, the first and second preset deviation ranges can be set according to the failure mode. It is generally believed that the increase in the measured value of exhaust manifold pressure compared with the pressure model value is mainly due to the position offset of the variable nozzle ring (e.g., the control opening is 50%, but the actual nozzle ring position is already 70%). It is generally believed that the decrease in the measured value of exhaust manifold pressure compared with the pressure model value is mainly due to exhaust manifold leakage (the main cause), exhaust manifold intake pipe seal failure or breakage, or exhaust manifold pressure sensor failure.
[0066] Through bench testing, at each engine speed and atmospheric pressure, the measured value of exhaust manifold pressure was simulated to increase (simulating variable nozzle ring offset) and the measured value of exhaust manifold pressure was simulated to decrease (adjusting exhaust manifold pressure sensor calibration).
[0067] Based on the engine's power, economy, smoke opacity, NOx emissions, knock pressure, and exhaust manifold temperature, determine whether the current nozzle ring offset is within an acceptable range. For example, in a flat environment, an acceptable range is considered to be a 5% loss in power, a 2% deterioration in economy, a 20% deterioration in smoke opacity and NOx emissions, a knock pressure increase of less than 5 bar, and an exhaust manifold temperature not exceeding 680°C. The above limits are defined based on whichever is met first.
[0068] Based on the above boundary conditions, a steady-state universal characteristic test was conducted, and the measured pressure values of the exhaust manifold pressure sensor, the exhaust manifold pressure model value, and the measured pressure values of the intake manifold were recorded.
[0069] Furthermore, the two differences between the measured value of the exhaust manifold pressure and the pressure model value at each speed and atmospheric pressure are identified and set as the first preset deviation range; the two differences between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure at each speed and atmospheric pressure are identified and set as the second preset deviation range.
[0070] Furthermore, in one embodiment, before obtaining the measured value and the pressure model value of the exhaust manifold pressure, the method further includes:
[0071] Determine whether the diagnostic conditions for the reasonableness of the exhaust manifold pressure are met; if so, it indicates that both the measured value and the pressure model value of the exhaust manifold pressure are reasonable. At this time, the measured value and the pressure model value of the exhaust manifold pressure can be obtained for subsequent diagnostic control.
[0072] Preferably, the above-mentioned exhaust manifold pressure rationality diagnostic conditions include:
[0073] Condition 1: The engine speed is within the preset speed range;
[0074] Condition 2: The throttle opening is greater than the preset opening;
[0075] Condition 3: The ambient temperature is within the preset temperature range, or the engine coolant temperature is greater than or equal to the temperature threshold. That is, when the ambient temperature is within the preset temperature range, or the engine coolant temperature is greater than or equal to the temperature threshold, condition 3 is satisfied.
[0076] Condition 4: Atmospheric pressure is within the preset pressure range;
[0077] Condition 5: The exhaust manifold pressure sensor, the intake manifold pressure sensor, and the exhaust manifold pressure model are all fault-free.
[0078] In this embodiment, the preset speed range can be set according to the engine's allowable operating range. Optionally, the preset speed range is from low idle speed to high idle speed. Here, low idle speed represents the stable speed after startup, and high idle speed represents the speed achievable at full throttle with the clutch disengaged.
[0079] Optionally, the preset opening is 2%. When the engine is under throttle and under engine braking, the measured value of the exhaust manifold pressure will deviate significantly from the pressure model value. Therefore, no further diagnostic control is performed under 0 throttle and braking conditions. When confirming the throttle range, diagnosis must be performed when the throttle opening is greater than 2%.
[0080] Optionally, the preset temperature range is 0-45℃, the preset temperature threshold is 60℃, and the preset pressure range is 50kPa-110kPa. Because the pressure model is more susceptible to conditional factors under extreme environmental conditions, no subsequent diagnostic control is performed under these conditions to prevent parallel problems caused by false alarms.
[0081] Furthermore, when the exhaust manifold pressure sensor and the intake manifold pressure sensor are valid, subsequent diagnostic control is performed. When a fault occurs that affects the exhaust manifold pressure model, it is determined that the exhaust manifold pressure rationality diagnostic conditions are not met, and subsequent diagnostic control is not performed.
[0082] In this embodiment, when the above-mentioned exhaust manifold pressure rationality diagnostic conditions are met, it indicates that the sensor status and vehicle status are good, that is, the exhaust manifold pressure sensor and intake manifold pressure sensor in the system are fault-free, the measured values are true and valid, the components in the vehicle are normal during operation, and there are no air system-related fault items.
[0083] Furthermore, when the ambient temperature is lower than the lower limit of the preset temperature range, the engine coolant temperature is lower than the temperature threshold, and the exhaust manifold pressure model is fault-free, the position of the turbocharger nozzle ring is controlled according to the pressure model value.
[0084] In this embodiment, under extreme ambient temperatures, the pressure pipeline before the vortex may freeze. When the ambient temperature is below 0°C and the water temperature is below 60°C, the VGT turbocharger position is controlled using the pressure model value. When the water temperature exceeds 60°C or the ambient temperature rises above 0°C, the judgment of the aforementioned exhaust manifold pressure rationality diagnosis conditions is restored.
[0085] In one embodiment, the above control method is mainly based on exhaust manifold pressure regulation. This control method consists of two stages: the first stage includes determining the reasonableness of exhaust manifold pressure diagnostic conditions and fault diagnosis; the second stage includes turbocharger nozzle ring position limitation protection control based on the fault diagnosis results. Specifically, fault diagnosis is only performed when the reasonableness of exhaust manifold pressure diagnostic conditions is met.
[0086] In this embodiment, during fault diagnosis, the measured value of exhaust manifold pressure is compared with the model value of exhaust manifold pressure. When the first difference between the two is within the first preset deviation range, or when the first difference exceeds the first preset deviation range and the second difference between the measured value of exhaust manifold pressure and the measured value of intake manifold pressure is within the second preset deviation range, it is considered that the engine is in good working condition, the system is working normally as a whole, and no exhaust manifold pressure deviation fault is reported, that is, the turbocharger position executes the normal logic control strategy.
[0087] When the first difference between the measured value of the exhaust manifold pressure and the model value of the exhaust manifold pressure exceeds the first preset deviation range, and the second difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure exceeds the upper limit of the second preset deviation range, the exhaust manifold pressure deviation upper limit fault is activated.
[0088] When the first difference between the measured value of the exhaust manifold pressure and the model value of the exhaust manifold pressure exceeds the first preset deviation range, and the second difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure is less than the lower limit of the second preset deviation range, the exhaust manifold pressure deviates below the lower limit fault is activated.
[0089] At this point, the second stage of limiting and protecting control is implemented. If no exhaust manifold pressure deviation fault is reported, i.e., the turbocharger position is executed according to the normal logic control strategy, the measured value of the exhaust manifold pressure is used for control. At this time, the turbocharger nozzle ring position is controlled according to the model opening degree and corrected according to the closed-loop control status.
[0090] When an exhaust manifold pressure exceeds the upper limit, it is assumed that there is a deviation in the exhaust manifold pressure model, which may cause the turbocharger to overspeed or have a limited position. In this case, the turbocharger nozzle ring position control is set to the first difference value for corresponding logic control. The turbocharger nozzle ring position is limited according to the actual exhaust manifold pressure to ensure that the turbocharger operates within a safe pressure range and prevent high-cycle fatigue caused by excessive exhaust manifold pressure.
[0091] When a fault occurs where the exhaust manifold pressure is below the lower limit, it is assumed that there is a problem with the exhaust manifold pressure sensor or pipeline. In this state, it is assumed that the pressure model value of the turbocharger is more accurate than the measured pressure. To ensure the safety and responsiveness of the engine, the turbocharger position control will execute an open-loop control strategy.
[0092] like Figure 2 As shown, the control method in this embodiment includes:
[0093] A1. Determine if the diagnostic conditions for reasonable exhaust manifold pressure are met; if yes, proceed to A2; otherwise, proceed to A1.
[0094] A2. Obtain the first difference between the measured value of the exhaust manifold pressure and the pressure model value;
[0095] A3. Determine whether the first difference is greater than the upper limit of the first preset deviation range. If yes, proceed to A5; otherwise, proceed to A4.
[0096] A4. Determine whether the first difference is less than the lower limit of the first preset deviation range. If yes, proceed to A6; otherwise, proceed to A8.
[0097] A5. Obtain the second difference and determine whether the second difference is greater than the upper limit of the second preset deviation range. If yes, proceed to A7; otherwise, proceed to A8. In this case, the second difference is assumed to be greater than or equal to the lower limit of the second preset deviation range.
[0098] A6. Obtain the second difference and determine whether the second difference is less than the lower limit of the second preset deviation range. If yes, go to A9; otherwise, go to A8. In this case, the second difference is assumed to be less than or equal to the upper limit of the second preset deviation range.
[0099] A7. Control the position of the turbocharger nozzle ring based on the first difference.
[0100] A8. Control the position of the turbocharger nozzle ring based on the measured value of the exhaust manifold pressure.
[0101] A9. Control the position of the booster nozzle ring based on the pressure model value.
[0102] The control method in this embodiment is designed for use when the turbocharger malfunctions. Without changing the current engine and aftertreatment layout or the turbocharger control logic of the main control unit, the method uses exhaust manifold pressure rationality fault judgment to control the pressure condition option for turbocharger position limitation (selecting actual sensor or model value) to solve the problem of turbocharger overspeed or premature position limitation.
[0103] Secondly, embodiments of this application also provide a control device for a variable nozzle ring booster that implements the above-described control method.
[0104] The control device for the aforementioned variable nozzle ring booster includes a first acquisition module, a second acquisition module, and a control module.
[0105] The first acquisition module is used to acquire the measured value of the exhaust manifold pressure and the pressure model value, and to acquire the difference between the two as the first difference.
[0106] The second acquisition module is used to acquire the measured value of the intake manifold pressure when the first difference exceeds the first preset deviation range, and to acquire the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure as the second difference.
[0107] The control module is used to control the position of the booster nozzle ring according to the first difference when the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range; the control module is also used to control the position of the booster nozzle ring according to the pressure model value when the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range.
[0108] Furthermore, in one embodiment, the control module is also used to control the position of the turbocharger nozzle ring based on the measured value of the exhaust manifold pressure when the first difference does not exceed the first preset deviation range or the second difference does not exceed the second preset deviation range.
[0109] Furthermore, in one embodiment, the control module is further configured to obtain a correction value for the nozzle ring position based on the first difference; and then correct the nozzle ring position based on the correction value.
[0110] Furthermore, in one embodiment, the first acquisition module is further configured to acquire the first deviation range of the current rotational speed and atmospheric pressure based on a pre-stored pulse spectrum of the first deviation range of rotational speed and atmospheric pressure, and after acquiring the first difference, compare the first difference with the first preset deviation range.
[0111] Furthermore, in one embodiment, the second acquisition module is further configured to acquire the second deviation range of the current rotational speed and atmospheric pressure based on a pre-stored pulse spectrum of the second deviation range of rotational speed and atmospheric pressure, and after acquiring the second difference, compare the second difference with the second preset deviation range.
[0112] Furthermore, in one embodiment, the control device further includes a judgment module, which is used to determine whether the exhaust manifold pressure rationality diagnosis conditions are met; if so, it indicates that both the measured value and the pressure model value of the exhaust manifold pressure are reasonable, and the result of the reasonable judgment is sent to the first acquisition module.
[0113] After receiving the result indicating that the judgment is reasonable, the first acquisition module obtains the measured value of the exhaust manifold pressure and the pressure model value.
[0114] The functions of each module in the control device of the variable nozzle ring booster correspond to the steps in the control method embodiment of the variable nozzle ring booster. Their functions and implementation processes will not be described in detail here.
[0115] The control device in this embodiment is applicable to the above-mentioned control methods and can be used in engines with variable nozzle ring turbocharger control strategies. It does not change the original logic architecture and the logic expansion is convenient. It solves the problems of turbocharger overspeed or position advance limitation, ensuring the safety of customers before repairing faults and reducing economic losses caused by vehicle breakdowns.
[0116] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.
[0117] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.
[0118] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.
Claims
1. A control method for a variable nozzle ring intensifier, characterized in that, The control method for the variable nozzle ring intensifier includes: Obtain the measured value and the pressure model value of the exhaust manifold pressure, and take the difference between the two as the first difference value. The pressure model value is obtained based on the exhaust manifold pressure model. When the first difference exceeds the first preset deviation range, the measured value of the intake manifold pressure is obtained, and the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure is obtained as the second difference. If the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range, then the position of the turbocharger nozzle ring is controlled according to the first difference. If the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range, then the position of the booster nozzle ring is controlled according to the pressure model value. The position of the turbocharger nozzle ring is controlled based on the first difference, specifically including: Based on the first difference, obtain the correction value for the nozzle ring position; The nozzle ring position is corrected according to the correction value.
2. The control method for the variable nozzle ring intensifier as described in claim 1, characterized in that: When the first difference does not exceed the first preset deviation range, or the second difference does not exceed the second preset deviation range, the position of the turbocharger nozzle ring is controlled according to the measured value of the exhaust manifold pressure.
3. The control method for the variable nozzle ring intensifier as described in claim 1, characterized in that, After obtaining the first difference, the method further includes comparing the first difference with a first preset deviation range; Before comparing the first difference with the first preset deviation range, the method further includes: Based on the pre-stored pulse spectrum of the first deviation range between rotational speed and atmospheric pressure, the first deviation range of the current rotational speed and atmospheric pressure is obtained.
4. The control method for the variable nozzle ring intensifier as described in claim 1, characterized in that, After obtaining the second difference, the method further includes comparing the second difference with a second preset deviation range; Before comparing the second difference with the second preset deviation range, the method further includes: Based on the pre-stored pulse spectrum of the second deviation range between rotational speed and atmospheric pressure, the second deviation range under the current rotational speed and atmospheric pressure is obtained.
5. The control method for the variable nozzle ring intensifier as described in claim 1, characterized in that: Before obtaining the measured and model values of the exhaust manifold pressure, the following steps are also included: Determine whether the diagnostic criteria for the reasonableness of the exhaust manifold pressure are met; if so, it indicates that both the measured value and the pressure model value of the exhaust manifold pressure are reasonable.
6. The control method for the variable nozzle ring intensifier as described in claim 5, characterized in that, The diagnostic criteria for the reasonableness of the exhaust manifold pressure include: The engine speed is within the preset speed range; The throttle opening is greater than the preset opening; The ambient temperature is within the preset temperature range, or the engine coolant temperature is greater than or equal to the temperature threshold. Atmospheric pressure is within the preset pressure range; The exhaust manifold pressure sensor, intake manifold pressure sensor, and exhaust manifold pressure model are all functioning correctly.
7. The control method for the variable nozzle ring intensifier as described in claim 5, characterized in that: When the ambient temperature is lower than the lower limit of the preset temperature range, the engine coolant temperature is lower than the temperature threshold, and the exhaust manifold pressure model is fault-free, the position of the turbocharger nozzle ring is controlled according to the pressure model value.
8. A control device for a variable nozzle ring intensifier implementing the control method of claim 1, characterized in that, The control device for the variable nozzle ring intensifier includes: The first acquisition module is used to acquire the measured value of the exhaust manifold pressure and the pressure model value, and to acquire the difference between the two as the first difference. The second acquisition module is used to acquire the measured value of the intake manifold pressure when the first difference exceeds the first preset deviation range, and to acquire the difference between the measured value of the exhaust manifold pressure and the measured value of the intake manifold pressure as the second difference. The control module is configured to control the position of the booster nozzle ring based on the first difference when the first difference is greater than the upper limit of the first preset deviation range and the second difference is greater than the upper limit of the second preset deviation range; and to control the position of the booster nozzle ring based on the pressure model value when the first difference is less than the lower limit of the first preset deviation range and the second difference is less than the lower limit of the second preset deviation range.
9. The control device for the variable nozzle ring intensifier as described in claim 8, characterized in that, The control module is also used to control the position of the turbocharger nozzle ring based on the measured value of the exhaust manifold pressure when the first difference does not exceed the first preset deviation range or the second difference does not exceed the second preset deviation range.