A filtering method, device and medium based on engine crankshaft rotation angle segments

Abstract

This invention discloses a filtering method, device, and medium based on engine crankshaft rotation angle segments, comprising the following steps: acquiring the engine synchronization state; responding to the engine synchronization state being synchronized and receiving a crankshaft segment change enable signal, sequentially acquiring pressure signals collected by engine intake manifold pressure sensors at sampling points within the crankshaft segment; accumulating and averaging at least four pressure signals sequentially collected within the crankshaft segment; determining the original sensor pressure value based on the average voltage of the pressure signals; accumulating the corresponding original sensor pressure values ​​within the crankshaft segment; summing the accumulated pressure value of the crankshaft segment with the accumulated pressure value of the previous crankshaft segment; summing the number of accumulations of the crankshaft segment with the number of accumulations of the previous crankshaft segment, and dividing the sum to obtain the engine intake manifold pressure after filtering based on crankshaft signal rotation angle segments, which can improve the working stability of the engine under various operating conditions.

Description

Technical Field

[0001] This invention belongs to the field of engine pressure acquisition technology, specifically relating to a filtering method, device, and medium based on engine crankshaft rotation angle segments. Background Technology

[0002] To meet increasingly stringent emission regulations, drivability, economy, and stability requirements, precise and real-time electronic control is an effective way for diesel engines to meet increasingly stringent performance indicators. Among these, electronically controlled high-pressure common rail technology has become the most important and mature direction in the current development of diesel engines.

[0003] In electronically controlled high-pressure common rail technology, it is necessary to collect pressure data in real time, such as the pressure after the engine air filter, the intake manifold pressure, and the exhaust DPF differential pressure. Based on these real-time pressures, the engine intake volume, fuel injection, throttle opening, and EGR opening are calculated. In one engine working cycle, each cylinder intakes and exhausts once, while the pressure sampling frequency at various points in the engine is typically 10ms.

[0004] For electronically controlled high-pressure common rail engine controllers, timely and accurate acquisition of pressure data at various points on the engine is a fundamental requirement for ensuring stable engine operation. Pressure data acquired from different points in the engine's air passages may drift after ordinary filtering. During rapid engine acceleration or changes in external characteristics, this can cause fluctuations in the intake air volume calculated by the air system based on the model, affecting engine drivability and worsening engine emissions.

[0005] Taking engine intake manifold pressure acquisition as an example: Generally, the engine intake manifold pressure is highest at the beginning of cylinder intake and lowest at the end of cylinder intake. Under the same operating conditions, the acquisition point of the engine intake manifold pressure will move back and forth between the beginning and end of cylinder intake due to engine rotation. This results in a significant drift in the engine intake manifold pressure under the same operating conditions, and ordinary filtering cannot eliminate this effect. This affects the stability of the entire engine electronic control system's air circuit control, and deteriorates engine performance, emissions, and other indicators. Summary of the Invention

[0006] To address the pressure drift issue caused by the reciprocating movement of pressure collection points at various points in the engine during the intake of each cylinder, this invention provides a filtering method, device, and medium based on segments of engine crankshaft rotation angle. This method achieves pressure filtering by segmenting the crankshaft rotation, thereby improving the engine's operational stability under various operating conditions.

[0007] The objective of this invention is achieved through the following technical solution:

[0008] The first aspect of this invention provides a filtering method based on engine crankshaft rotation angle segments, comprising the following steps:

[0009] The synchronization status of the engine is obtained, which includes a synchronized state and an asynchronous state. The synchronized state includes a fully synchronized state and a semi-synchronized state, and the asynchronous state includes an unsynchronized state and a synchronization failure state.

[0010] In response to the engine being in a synchronized state and receiving a crankshaft segment change enable signal, the pressure signals collected by the engine intake manifold pressure sensor at the sampling point within the crankshaft segment are sequentially acquired. The crankshaft segment corresponds to a crankshaft rotation of 720 / X / 2 degrees, where X is the number of cylinders in the engine.

[0011] The average value of the pressure signal voltage is obtained by accumulating and averaging at least four pressure signals sequentially acquired within the crankshaft segment.

[0012] The original pressure value of the sensor is determined based on the average voltage value of the pressure signal.

[0013] The original sensor pressure values ​​within the corresponding crankshaft segment are accumulated to obtain the accumulated pressure value of the crankshaft segment.

[0014] The cumulative pressure value of this crankshaft segment is summed with the cumulative pressure value of the previous crankshaft segment, and the cumulative count of this crankshaft segment is summed with the cumulative count of the previous crankshaft segment. The two are then divided to obtain the engine intake manifold pressure after filtering based on the crankshaft signal angle segment.

[0015] A second aspect of the present invention provides a filtering device based on engine crankshaft rotation angle segments, comprising a memory and a controller connected in sequence, wherein the memory stores a computer program, and the controller is used to read the computer program and execute a filtering method based on engine crankshaft rotation angle segments as described in the first aspect and any of its possibilities.

[0016] A third aspect of the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, perform a filtering method based on an engine crankshaft rotation angle segment as described in the first aspect and any of its possibilities.

[0017] Compared with the prior art, the present invention has at least the following advantages and beneficial effects:

[0018] This invention achieves pressure filtering by segmenting the crankshaft rotation, which can more accurately obtain the pressure of the engine's intake or exhaust system and improve the engine's working stability under various operating conditions. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the method of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0022] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined with each other.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only used for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. In addition, the terms "first," "second," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0027] The first aspect of this invention discloses a filtering method based on engine crankshaft rotation angle segments. This method can be, but is not limited to, executed by a filtering device based on engine crankshaft rotation angle segments. The filtering device can be software or a combination of software and hardware. Specifically, as... Figure 1 As shown, the filtering method based on engine crankshaft rotation angle segments includes the following steps S01 to S07. It should be noted that the step labels in this scheme are only for the convenience of describing the method and do not constitute a limitation on the order of steps. The order of each step is based on its verbal description and the sequential connection of each signal.

[0028] Step S01: Obtain the engine synchronization status. The engine synchronization status includes a synchronized state and an asynchronous state. The synchronized state includes a fully synchronized state and a semi-synchronized state. The asynchronous state includes an unsynchronized state and a synchronization failure state.

[0029] Step S02: In response to the engine being in a synchronized state and receiving a crankshaft segment change enable signal, sequentially acquire the pressure signals collected by the engine intake manifold pressure sensor at the sampling point within the crankshaft segment. The crankshaft segment corresponds to a crankshaft rotation of 720 / X / 2 degrees, where X is the number of cylinders in the engine.

[0030] In each working cycle of the engine, the crankshaft rotates twice, and each cylinder performs four working cycles: intake, compression, power, and exhaust. To eliminate pressure fluctuations caused by intake or exhaust in each cylinder, this design divides the crankshaft rotation into 2X crankshaft segments, each segment being 720 / X / 2 degrees.

[0031] For example, a four-cylinder engine divides the crankshaft rotation process in each working cycle into 8 crankshaft segments, each crankshaft segment being 90°; a six-cylinder engine divides the crankshaft rotation process in each working cycle into 12 crankshaft segments, each crankshaft segment being 60°.

[0032] Each time the crankshaft rotates into a crankshaft segment, a crankshaft segment change enable signal Air_SegChgTrig is generated. Taking a four-cylinder engine as an example, eight crankshaft segment change enable signals Air_SegChgTrig can be generated in one working cycle.

[0033] Step S03: Accumulate and average at least four pressure signals sequentially acquired within the crankshaft segment to obtain the average voltage value of the pressure signals.

[0034] The pressure signal is the original voltage signal Air_uRawPIntkVUs_HW from the engine intake manifold pressure sensor. The pressure sensor collects pressure at a preset frequency, so in a crankshaft segment, the pressure sensor will continuously collect multiple pressure signals.

[0035] For example, if a pressure sensor in a crankshaft segment collects N pressure signals, where N is a natural number greater than or equal to 4, the average voltage of the N-3 pressure signals can be calculated.

[0036] Step S04: Determine the original value of the sensor pressure based on the average voltage of the pressure signal.

[0037] Specifically, this step involves looking up the average pressure signal voltage in a table to convert it into the raw sensor pressure value, Air_pSensRaw. The table stores the correspondence between the average pressure signal voltage and the raw sensor pressure value, allowing for direct conversion via table lookup.

[0038] Step S05: Accumulate the original sensor pressure values ​​corresponding to the crankshaft segment to obtain the accumulated pressure value of the crankshaft segment.

[0039] This step involves accumulating the above N-3 pressure signals to obtain the accumulated pressure value Air_pSegSum.

[0040] Step S06: Sum the accumulated pressure value of the current crankshaft segment with the accumulated pressure value of the previous crankshaft segment, sum the accumulated number of the current crankshaft segment with the accumulated number of the previous crankshaft segment, and divide the two to obtain the engine intake manifold pressure after filtering based on the crankshaft signal angle segment.

[0041] This step involves calculating the average of the cumulative pressure values ​​Air_pSegSum of two adjacent crankshaft segments to obtain the average pressure value Air_pSensPIntkVUsAvr of the engine under synchronized conditions.

[0042] Step S07: In response to the engine's synchronization state being asynchronous and receiving a crankshaft segment change enable signal, sequentially acquire the pressure signals collected by the engine intake manifold pressure sensor at the sampling point within the crankshaft segment; accumulate and average the at least 4 pressure signals sequentially collected within the crankshaft segment to obtain the average pressure signal voltage; determine the original sensor pressure value based on the average pressure signal voltage; and use the original sensor pressure value as the average pressure value.

[0043] Specifically, the detailed operation process of this step can be found in steps S02 to S04. Repeated steps will not be described in detail here.

[0044] Using the above method, when the engine is in a synchronized state, the average pressure value Air_pSensPIntkVUsAvr is used as the final average pressure value of the engine intake manifold pressure sensor for filtering. When the engine is in a asynchronous state, the original sensor pressure value Air_pSensRaw is directly used as the final average pressure value of the engine intake manifold pressure sensor.

[0045] This method can solve the problem of pressure drift caused by the back-and-forth movement of pressure collection points at various points in the engine as the engine rotates from the start to the end of intake in each cylinder, thus improving the working stability of the engine under various operating conditions.

[0046] Using this method, the existing configuration of the engine's electronically controlled high-pressure common rail system can be improved without adding any other hardware. Only by adding a software control module, namely a filtering device, and using a filtering strategy based on the engine crankshaft rotation angle segment, the pressure collected from various parts of the engine can be processed, which can effectively improve the working stability of the engine under various operating conditions.

[0047] Based on engine bench and vehicle tests, after adopting the filtering strategy based on engine crankshaft rotation angle segments, the pressure sensors at various points such as the engine intake manifold and DPF differential pressure can remain stable near the actual value under stable conditions throughout the entire engine operating conditions, without fluctuations in the strategy pressure due to different engine speeds; and under dynamic conditions, they can quickly and accurately follow the actual pressure value.

[0048] A second aspect of this invention provides a filtering device based on engine crankshaft rotation angle segments, comprising a memory and a controller connected in sequence. The memory stores a computer program, and the controller is used to read the computer program and execute a filtering method based on engine crankshaft rotation angle segments as described in the first aspect and any possible embodiment thereof. Specifically, the memory may include, but is not limited to, random-access memory (RAM), read-only memory (ROM), flash memory, first-in-first-out (FIFO) memory, and / or first-in-last-out (FILO) memory, etc.; the controller may not be limited to using a microcontroller of the STM32F105 series. Furthermore, the computer device may also include, but is not limited to, a power supply unit, a display screen, and other necessary components.

[0049] A third aspect of the present invention provides a computer-readable storage medium storing instructions that, when executed on a computer, perform a filtering method based on an engine crankshaft rotation angle segment as described in the first aspect and any of its possibilities.

[0050] The apparatus and medium provided in the second and third aspects of the present invention operate on the same principle as those in the first aspect, as detailed in the first aspect, and will not be repeated here.

[0051] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A filtering method based on engine crankshaft rotation angle segments, characterized in that, Includes the following steps: The synchronization status of the engine is obtained, which includes a synchronized state and an asynchronous state. The synchronized state includes a fully synchronized state and a semi-synchronized state, and the asynchronous state includes an unsynchronized state and a synchronization failure state. In response to the engine being in a synchronized state and receiving a crankshaft segment change enable signal, the pressure signals collected by the engine intake manifold pressure sensor at the sampling point within the crankshaft segment are sequentially acquired. The crankshaft segment corresponds to a crankshaft rotation of 720 / X / 2 degrees, where X is the number of cylinders in the engine. The average value of the pressure signal voltage is obtained by accumulating and averaging at least four pressure signals sequentially acquired within the crankshaft segment. The original pressure value of the sensor is determined based on the average voltage value of the pressure signal. The original sensor pressure values ​​within the corresponding crankshaft segment are accumulated to obtain the accumulated pressure value of the crankshaft segment. The cumulative pressure value of this crankshaft segment is summed with the cumulative pressure value of the previous crankshaft segment, and the cumulative count of this crankshaft segment is summed with the cumulative count of the previous crankshaft segment. The two are then divided to obtain the engine intake manifold pressure after filtering based on the crankshaft signal angle segment.

2. The filtering method based on engine crankshaft rotation angle segments according to claim 1, characterized in that: The original pressure value of the sensor is determined based on the average voltage value of the pressure signal: The average pressure signal voltage is used to look up a table and convert the average pressure signal voltage into the original sensor pressure value.

3. The filtering method based on engine crankshaft rotation angle segments according to claim 1, characterized in that: After obtaining the engine's synchronization status, the process also includes: In response to the engine being out of sync and receiving a crankshaft segment change enable signal, the pressure signals collected by the engine intake manifold pressure sensor at the sampling point within the crankshaft segment are acquired sequentially. The average value of the pressure signal voltage is obtained by accumulating and averaging at least four pressure signals sequentially acquired within the crankshaft segment. The original pressure value of the sensor is determined based on the average voltage value of the pressure signal. The original pressure value of the sensor is used as the average pressure value.

4. A filtering device based on engine crankshaft rotation angle segments, comprising a memory and a controller connected in sequence, wherein the memory stores a computer program, characterized in that: The controller is used to read the computer program and execute the filtering method based on engine crankshaft rotation angle segments as described in any one of claims 1-3.

5. A computer-readable storage medium storing instructions thereon, characterized in that: When the instruction is executed on a computer, it performs a filtering method based on engine crankshaft rotation angle segments as described in any one of claims 1-3.

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