A method and device for determining an ignition advance angle and a vehicle

Abstract

The present invention provides a method and device for determining an ignition advance angle, and a vehicle, and relates to the field of vehicle control. The method comprises: determining a target correction value of the ignition advance angle of a target cylinder according to the current engine speed, and determining the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder. The method for determining the ignition advance angle of an embodiment of the present invention determines a target correction value of the ignition advance angle of a target cylinder according to the current engine speed, and finally determines the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder. The problem of the delay in the ignition advance angle of the target cylinder due to the delay time of the crankshaft signal is avoided, so that the performance of the engine is greatly improved, and the engine power, economy and emission become better, which indirectly improves the user experience and has a high practical value.

Description

Technical Field

[0001] The invention relates to the field of automobile control, and in particular to a method and device for determining an ignition advance angle and an automobile. Background Art

[0002] With the development of the automobile industry and the advancement of technology, the number of cylinders in engines has gradually increased. Widely known are 4-cylinder engines, 6-cylinder engines, 8-cylinder engines, 12-cylinder engines and even 16-cylinder engines.

[0003] Generally speaking, as the number of cylinders increases, the arrangement is not limited to in-line. For example, 4-cylinder engines are generally arranged in-line, while 6-cylinder engines have two types of in-line and V-shaped arrangements, namely V6 engines. The cylinder arrangement is V-shaped, generally with an angle of 60 degrees. The 6 cylinders are divided into two rows, 3 in each row, called double BANK. 8-cylinder engines and 12-cylinder engines generally use this V-shaped arrangement.

[0004] As we all know, the crankshaft position is a key parameter that determines the cylinder ignition advance angle. Generally, when the throttle opening and intake volume are determined, the electronic control unit (ECU) needs to control the cylinder ignition advance angle according to the crankshaft position signal. However, for the above-mentioned V-shaped cylinder arrangement, since there is only one crankshaft sensor, the crankshaft position signal can only be sent to the main ECU that controls the ignition advance angle of some cylinders, while the auxiliary ECU that controls the ignition advance angle of the other cylinders can only receive the crankshaft signal forwarded by the main ECU. There is a signal delay in the forwarding of the crankshaft signal, which will cause the auxiliary ECU to delay receiving the crankshaft signal, resulting in a delay in the ignition advance angle of the cylinder it controls, which in turn causes the engine performance to decline, and the engine power, economy and emissions are poor. Summary of the invention

[0005] The present invention provides a method and device for determining an ignition advance angle and a vehicle, which solves the problem of cylinder ignition advance angle delay error caused by signal delay in forwarding crankshaft signals.

[0006] In order to solve the above technical problem, a first aspect of an embodiment of the present invention provides a method for determining an ignition advance angle, which is applied to a first electronic control unit. The method includes:

[0007] Determine a target correction value of the ignition advance angle of the target cylinder according to the current engine speed, wherein the target correction value represents: an angle that the crankshaft rotates based on the current engine speed during a transmission time when the crankshaft position signal is transmitted from the second electronic control unit to the first electronic control unit;

[0008] A target ignition advance angle of the target cylinder is determined based on the target correction value and the original ignition advance angle of the target cylinder.

[0009] Optionally, determining a target correction value of the ignition advance angle of the target cylinder according to the current engine speed includes:

[0010] According to the current engine speed, a preset correction value curve is queried to determine the target correction value, wherein the correction value curve indicates the corresponding relationship between the engine speed and the correction value.

[0011] Optionally, determining the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder comprises:

[0012] The sum of the original ignition advance angle of the target cylinder and the target correction value is determined as the target ignition advance angle of the target cylinder.

[0013] Optionally, the crankshaft position signal is collected by a crankshaft position sensor and directly sent to the second electronic control unit;

[0014] After receiving the crankshaft position signal, the second electronic control unit transmits the crankshaft position signal to the first electronic control unit;

[0015] The transmission time of the crankshaft position signal from the second electronic control unit to the first electronic control unit is the delay time in the transmission process of the crankshaft position signal.

[0016] Optionally, the correction value curve is obtained by the following method:

[0017] Determining the number of the flywheel teeth that the crankshaft rotates through during the delay time according to the engine speed and the number of the flywheel teeth;

[0018] According to the angle corresponding to each tooth in the flywheel teeth and the number of the flywheel teeth rotated by the crankshaft during the delay period, the angle of rotation of the crankshaft during the delay period is determined, and the angle is the correction value;

[0019] The correction value curve is drawn with the engine speed as the horizontal axis and the correction value as the vertical axis.

[0020] Optionally, the delay time is determined by a software filter coefficient in the second electronic control unit.

[0021] A second aspect of an embodiment of the present invention provides a device for determining an ignition advance angle, which is applied to a first electronic control unit, and the device includes:

[0022] a target correction value determination module, configured to determine a target correction value of an ignition advance angle of a target cylinder according to a current engine speed, wherein the target correction value represents: an angle that a crankshaft rotates based on the current engine speed during a transmission time when a crankshaft position signal is transmitted from a second electronic control unit to the first electronic control unit;

[0023] The target ignition angle determination module is used to determine the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder.

[0024] Optionally, the target correction value determination module is specifically used to:

[0025] According to the current engine speed, a preset correction value curve is queried to determine the target correction value, wherein the correction value curve indicates the corresponding relationship between the engine speed and the correction value.

[0026] Optionally, the module for determining the target ignition angle is specifically used for:

[0027] The sum of the original ignition advance angle of the target cylinder and the target correction value is determined as the target ignition advance angle of the target cylinder.

[0028] Optionally, the device further comprises: a correction value curve acquisition module, wherein the correction value curve acquisition module specifically comprises:

[0029] A flywheel teeth number determination unit, used for determining the number of the flywheel teeth that rotate during the delay time according to the engine speed and the number of the flywheel teeth;

[0030] A crankshaft rotation angle determination unit is used to determine the crankshaft rotation angle within the delay time according to the angle corresponding to each tooth in the flywheel teeth, the number of the flywheel teeth rotated per unit time, and the delay time, and take the negative value of the angle as the correction value;

[0031] The curve drawing unit is used to draw the correction value curve with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate.

[0032] A third aspect of an embodiment of the present invention provides a vehicle, the vehicle comprising: a first electronic control unit, a second electronic control unit and a crankshaft position sensor;

[0033] The crankshaft position sensor collects the crankshaft position signal and directly sends it to the second electronic control unit;

[0034] After receiving the crankshaft position signal, the second electronic control unit transmits the crankshaft position signal to the first electronic control unit;

[0035] The first electronic control unit is used to execute the method for determining the ignition advance angle described in any one of the first aspects.

[0036] The method for determining the ignition advance angle provided by the present invention comprehensively considers the time lost during the transmission of the crankshaft position signal (i.e., signal delay), which will cause the actual position of the crankshaft to be inconsistent with the position reflected by the crankshaft position signal, and the influence of the two factors of the difference in the crankshaft rotation angle at different engine speeds during the loss time. Therefore, in the actual engine operation process, it is preferred to determine the target correction value of the ignition advance angle of the target cylinder according to the current engine speed. The target correction value represents: the angle of rotation of the crankshaft based on the current engine speed during the time lost during the transmission of the crankshaft position signal. After determining the target correction value, the target ignition advance angle of the target cylinder can be determined according to the target correction value and the original ignition advance angle of the target cylinder. In this way, the ignition advance angle of the target cylinder is corrected, and the problem of the delay error of the cylinder ignition advance angle caused by the signal delay in the forwarding of the crankshaft signal is avoided, so that the performance of the engine is greatly improved, and the natural engine power, economy and emission become better, which indirectly improves the user experience and has a high practical value. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0038] Figure 1 This is a diagram of the current arrangement of the cylinders of a V6 engine;

[0039] Figure 2 is a flow chart of a method for determining an ignition advance angle according to an embodiment of the present invention;

[0040] Figure 3 The invention is a block diagram of a device for determining an ignition advance angle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The inventors have discovered that the current V-shaped cylinder arrangement has only one crankshaft sensor, so the crankshaft position signal can only be sent to the main ECU that controls the ignition advance angle of some cylinders, while the sub-ECU that controls the ignition advance angle of another part of the cylinders can only receive the crankshaft signal forwarded by the main ECU. There will be a signal delay in the process of transmitting the crankshaft signal from the main ECU to the sub-ECU, which will cause the sub-ECU to delay in receiving the crankshaft signal, resulting in a delay and error in the ignition advance angle of the cylinder it controls, thereby causing a decline in engine performance, and poor engine power, economy and emissions.

[0043] For example: Figure 1 The diagram shows the arrangement of cylinders in the current V6 engine. Figure 1 It includes: engine body 10, crankshaft position sensor 20, engine harness 30, 40, crankshaft signal transmission line 50 (the transmission line is hard wire), main ECU 60 and sub-ECU 70. Among them, the engine body 10 includes: cylinders ①, ②, ③, ④, ⑤, ⑥, and the ignition sequence is ①, ④, ②, ⑤, ③, ⑥. Since there is only one crankshaft position sensor, the main ECU that controls the ignition advance angle of cylinders ①, ②, ③ can directly receive the crankshaft position signal sent by the crankshaft position sensor, but the sub-ECU that controls the ignition advance angle of cylinders ④, ⑤, ⑥ cannot directly receive the crankshaft position signal sent by the crankshaft position sensor, but is forwarded by the main ECU, so there is a crankshaft position signal delay, that is, when the sub-ECU receives the crankshaft position signal, the actual position of the crankshaft is no longer the position indicated in the crankshaft signal.

[0044] Generally, the ECU controls the ignition of each cylinder in the engine by relying on the crankshaft position signal. The ignition advance angle is fixed after the throttle opening and intake volume are determined. So after the cylinder arrangement in the engine is fixed, the corresponding cylinder ignition angle after the crankshaft rotates a certain angle is known. As an example: Figure 1 Take the V6 engine cylinder shown in the figure as an example. After the throttle opening and intake volume are determined, it is assumed that the ignition advance angle of the six cylinders is 6°. According to the engine movement law, the ignition timing difference between two adjacent cylinders is 720° / 6°=120°, that is, the corresponding cylinder will ignite in accordance with the ignition sequence every time the crankshaft rotates 120°. Assuming that cylinder ① ignites when the crankshaft is at a certain position, the position is set as the starting 0° of the crankshaft rotation. When the main ECU receives the position represented by the crankshaft position signal as the starting 0°, it sends an ignition signal to make the spark plug of cylinder ① ignite. Then, when the crankshaft continues to rotate 6° after the starting 0°, cylinder ① runs to the top dead center of its piston, and the oil-gas mixing reaches the best effect.

[0045] The crankshaft continues to rotate. When the position represented by the crankshaft position signal received by the sub-ECU is 120° based on the above-mentioned starting 0°, an ignition signal is sent to ignite the spark plug of cylinder ④. Then, when the crankshaft continues to rotate 6° after 120°, that is, when the crankshaft rotates to 126° based on the above-mentioned starting 0°, cylinder ④ runs to the top dead center of its piston, and the oil-gas mixing reaches the best effect.

[0046] However, since the slave ECU receives the crankshaft position signal forwarded by the main ECU, there will be a signal delay during the transmission of the crankshaft position signal. Therefore, the crankshaft signal received by the slave ECU can no longer correctly represent the actual position of the crankshaft. It can be understood that the actual position of the crankshaft must have rotated beyond the crankshaft position corresponding to the crankshaft signal received by the slave ECU, and the higher the engine speed, the greater the actual rotation angle of the crankshaft during the delay time.

[0047] In order to overcome the above problems, the inventors further studied and found that the delay of the main ECU forwarding the crankshaft position signal is determined by the software filter coefficient in the main ECU, and has nothing to do with the engine speed. That is, the delay time of the crankshaft position signal will not change with the change of the engine speed. Once the software filter coefficient is determined, the delay time of the crankshaft position signal is determined.

[0048] Based on the above findings, the inventors have conducted a lot of research, calculations, simulations and field tests, and creatively proposed a method for determining the ignition advance angle of the present invention. The technical solution of the present invention is described and explained in detail below.

[0049] Figure 2 A flow chart of a method for determining an ignition advance angle according to an embodiment of the present invention is shown. The method is applied to a first electronic control unit and includes:

[0050] Step 201: Determine a target correction value of the ignition advance angle of the target cylinder according to the current engine speed, wherein the target correction value represents: the angle of rotation of the crankshaft based on the current engine speed during the transmission time of the crankshaft position signal from the second electronic control unit to the first electronic control unit.

[0051] In an embodiment of the present invention, the crankshaft position signal is collected by a crankshaft position sensor and directly sent to a second electronic control unit (i.e., a second ECU). After receiving the signal, the second ECU forwards it to the first electronic control unit (i.e., the first ECU). The transmission time of the crankshaft position signal from the second ECU to the first ECU is the delay time of the crankshaft signal, which is determined by the software filter coefficient in the second ECU. When the software filter coefficient in the second ECU is determined, the delay time t of the crankshaft signal can be obtained. Combined with the current engine speed, the angle of crankshaft rotation within the delay time t can be obtained, and the angle is the target correction value of the ignition advance angle of the target cylinder at the current engine speed.

[0052] In an embodiment of the present invention, a preferred method for determining the target correction value according to the current engine speed may be: according to the current engine speed, querying a preset correction value curve to determine the target correction value, wherein the correction value curve indicates the corresponding relationship between the engine speed and the correction value. The specific method for obtaining the correction value curve is described below and will not be repeated here.

[0053] Continuing with the above example: Figure 1 Take the V6 engine cylinders shown in as an example: the ignition advance angle of cylinders ①, ②, and ③ is controlled by the main ECU (i.e., the second ECU), and the ignition advance angle of cylinders ④, ⑤, and ⑥ is controlled by the auxiliary ECU (i.e., the first ECU). Assuming the delay time is 1ms and the engine speed is 1000rpm, the calculation can obtain that the actual rotation angle of the crankshaft within the delay time of 1ms is 6°, that is, this 6° angle is the target correction value of cylinders ④, ⑤, and ⑥; assuming the delay time is 1ms and the engine speed is 3000rpm, the calculation can obtain that the actual rotation angle of the crankshaft within the delay time of 1ms is 18°, that is, this 18° angle is the target correction value of cylinders ④, ⑤, and ⑥.

[0054] Step 202: Determine the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder.

[0055] In the embodiment of the present invention, after obtaining the target correction value of the ignition advance angle of the target cylinder, the first ECU can determine the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder. The so-called original ignition advance angle of the target cylinder refers to: the ignition advance angle of the target cylinder when there is no delay time in the transmission of the crankshaft signal, that is, when the throttle opening and the intake volume are determined, and the crankshaft position signal can accurately represent the actual position of the crankshaft.

[0056] In an embodiment of the present invention, a preferred method for determining the target ignition advance angle based on the target correction value and the original ignition advance angle may be: the sum of the original ignition advance angle of the target cylinder and the target correction value is determined as the target ignition advance angle of the target cylinder.

[0057] Continuing with the above example: Figure 1 Take the V6 engine cylinders shown in as an example: the ignition advance angle of cylinders ①, ②, and ③ is controlled by the main ECU (i.e., the second ECU), and the ignition advance angle of cylinders ④, ⑤, and ⑥ (i.e., the target cylinders) is controlled by the slave ECU (i.e., the first ECU). Assuming that the original ignition advance angles of cylinders ①, ②, ③, ④, ⑤, and ⑥ are all 6°, the delay time is 1ms, the engine speed is 1000rpm, and the target correction value of cylinders ④, ⑤, and ⑥ is 6°, then the target ignition advance angle of cylinders ④, ⑤, and ⑥ is: 6°+6°=12°, and when the slave ECU receives the crankshaft position signal indicating that the position is 114° (no longer 120°) based on the above starting 0°, it sends an ignition signal to ignite the spark plug of cylinder ④, then when the crankshaft continues to rotate 12° after 114°, that is, when the crankshaft rotates to 126° based on the above starting 0°, cylinder ④ runs to the top dead center of its piston, and the oil-gas mixing reaches the best effect.

[0058] Assuming that the delay time is 1ms, the engine speed is 3000rpm, and the target correction value of cylinders ④, ⑤, and ⑥ is 18°, then the target ignition advance angle of cylinders ④, ⑤, and ⑥ is: 6°+18°=24°. Then, when the auxiliary ECU receives the crankshaft position signal representing a position that is 102° (no longer 120°) rotated based on the above-mentioned starting 0°, it sends an ignition signal to cause the spark plug of cylinder ④ to ignite. Then, when the crankshaft continues to rotate 24° after 102°, that is, when the crankshaft rotates to 126° based on the above-mentioned starting 0°, cylinder ④ runs to the top dead center of its piston, and the oil-gas mixing achieves the best effect.

[0059] In the embodiment of the present invention, the correction value curve is obtained by the following method:

[0060] Step S1: Determine the number of flywheel teeth that the crankshaft rotates through during the delay time according to the engine speed and the number of flywheel teeth.

[0061] In the embodiment of the present invention, the correction value curve is first determined by determining the number of flywheel teeth that the crankshaft rotates during the delay time based on the engine speed and the number of flywheel teeth. Generally, there are 60 teeth on the flywheel of the engine, 2 of which are missing, and the size of each flywheel tooth is the same. Then the higher the engine speed, the more flywheel teeth the crankshaft rotates during the same time. That is, after the delay time is determined, the higher the engine speed is during the delay time, the more flywheel teeth the crankshaft rotates. According to the specific delay time, the specific number of flywheel teeth and the specific engine speed, the number of flywheel teeth that the crankshaft rotates during the delay time can be determined.

[0062] For example: the engine speed is 1000rpm, which is 360000° / 60000ms, and the number of flywheel teeth is 60. Since the size of each flywheel tooth is the same, the time it takes to pass each flywheel tooth is equal. After calculation, it can be known that the crankshaft rotates through 1 flywheel tooth every 1ms. The same principle can be used to deduce that when the engine speed is 3000rpm, the crankshaft rotates through 3 flywheel teeth every 1ms. When the delay time is determined by the filter coefficient of the software, the number of flywheel teeth that the crankshaft rotates through at different engine speeds during the delay time can be known. Assuming the delay time is 0.5ms, when the engine speed is 1000rpm, the crankshaft rotates 0.5 flywheel teeth, and when the engine speed is 3000rpm, the crankshaft rotates 1.5 flywheel teeth; assuming the delay time is 1ms, when the engine speed is 1000rpm, the crankshaft rotates 1 flywheel tooth, and when the engine speed is 3000rpm, the crankshaft rotates 3 flywheel teeth.

[0063] Step S2: According to the angle corresponding to each tooth in the flywheel teeth and the number of the flywheel teeth rotated by the crankshaft during the delay time, the angle of rotation of the crankshaft during the delay time is determined, and the angle is the correction value.

[0064] In the embodiment of the present invention, after determining the number of flywheel teeth that the crankshaft rotates through during the delay time, since there are 60 teeth on the flywheel of the engine, it is equivalent to that each flywheel tooth corresponds to 6°. Therefore, the angle corresponding to each tooth in the flywheel and the number of flywheel teeth that the crankshaft rotates through during the delay time can be multiplied, and the product of the two can be determined as the angle of rotation of the crankshaft during the delay time, and this angle is the correction value.

[0065] For example: when the delay time is 0.5ms, if the engine speed is 1000rpm, the crankshaft rotates over 0.5 flywheel teeth, and the angle of the crankshaft rotation during the 0.5ms delay time is 0.5*6°=3°, and this 3° is the correction value; if the engine speed is 3000rpm, the crankshaft rotates over 1.5 flywheel teeth, and the angle of the crankshaft rotation during the 0.5ms delay time is 1.5*6°=9°, and this 9° is the correction value. Assuming the delay time is 1ms, if the engine speed is 1000rpm, the crankshaft rotates over 1 flywheel tooth, and the angle of the crankshaft rotation during the 0.5ms delay time is 1*6°=6°, and this 6° is the correction value. If the engine speed is 3000rpm, the crankshaft rotates over 3 flywheel teeth, and the angle of the crankshaft rotation during the 0.5ms delay time is 3*6°=18°, and this 18° is the correction value.

[0066] Step S3: Draw a correction value curve with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate.

[0067] Through the above steps S1 to S2, the correction value of the target cylinder at different engine speeds within a specific delay time can be obtained, and then the correction value curve is drawn with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate. The correction value curve can be saved in the first ECU. In actual use, since the software filter coefficient of the second ECU can be known in advance, the delay time is actually a fixed value. According to the specific delay time, the correction value curve suitable for the target cylinder of the engine can be obtained. The first ECU only needs to query this correction value curve according to the actual speed of the current engine to obtain the target correction value, and then add it to the original advance ignition angle of the target cylinder to obtain the target ignition advance angle of the target cylinder.

[0068] Of course, it is also possible to not need the correction value curve, input the delay time, the number of flywheel teeth and the generator speed into the first ECU, and let the first ECU perform calculations according to the above method to obtain the target ignition advance angle of the target cylinder. This requires the first ECU to have a high computing power to ensure the correct target ignition advance angle.

[0069] Based on the above-mentioned method for determining the ignition advance angle, an embodiment of the present invention further provides a device for determining the ignition advance angle, which is applied to a first electronic control unit, referring to Figure 3 , shows a block diagram of a device for determining an ignition advance angle according to the present invention, the device for determining an ignition advance angle comprising:

[0070] The target correction value determination module 310 is used to determine a target correction value of the ignition advance angle of the target cylinder according to the current engine speed, wherein the target correction value represents: an angle that the crankshaft rotates based on the current engine speed during the transmission time of the crankshaft position signal from the second electronic control unit to the first electronic control unit;

[0071] The target ignition angle determination module 320 is used to determine the target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder.

[0072] Optionally, the target correction value determination module 310 is specifically configured to:

[0073] According to the current engine speed, a preset correction value curve is queried to determine the target correction value, wherein the correction value curve indicates the corresponding relationship between the engine speed and the correction value.

[0074] Optionally, the target ignition angle determination module 320 is specifically used for:

[0075] The sum of the original ignition advance angle of the target cylinder and the target correction value is determined as the target ignition advance angle of the target cylinder.

[0076] Optionally, the device further comprises: a correction value curve acquisition module, wherein the correction value curve acquisition module specifically comprises:

[0077] A flywheel teeth number determination unit, used for determining the number of the flywheel teeth that rotate during the delay time according to the engine speed and the number of the flywheel teeth;

[0078] A crankshaft rotation angle determination unit is used to determine the crankshaft rotation angle within the delay time according to the angle corresponding to each tooth in the flywheel teeth, the number of the flywheel teeth rotated per unit time, and the delay time, and take the negative value of the angle as the correction value;

[0079] The curve drawing unit is used to draw the correction value curve with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate.

[0080] Based on the above method for determining the ignition advance angle, an embodiment of the present invention further provides a vehicle, the vehicle comprising: a first electronic control unit, a second electronic control unit and a crankshaft position sensor;

[0081] The crankshaft position sensor collects the crankshaft position signal and directly sends it to the second electronic control unit;

[0082] After receiving the crankshaft position signal, the second electronic control unit transmits the crankshaft position signal to the first electronic control unit;

[0083] The first electronic control unit is used to execute the method for determining the ignition advance angle described in steps 201 to 202 above.

[0084] Through the above embodiments, the method for determining the ignition advance angle of the embodiment of the present invention comprehensively considers the delay time of the crankshaft position signal transmission, which will cause the actual position of the crankshaft to be inconsistent with the position reflected by the crankshaft position signal, and the influence of the two factors of the difference in the crankshaft rotation angle at different engine speeds during the loss time. According to the delay time determined by the software filter coefficient, the correction value of the target cylinder at different engine speeds is obtained. In actual use, according to the current engine speed, the target correction value of the ignition advance angle of the target cylinder is determined, and finally, according to the target correction value and the original ignition advance angle of the target cylinder, the target ignition advance angle of the target cylinder is determined. In this way, the ignition advance angle of the target cylinder is corrected, and the problem of the delay error of the cylinder ignition advance angle caused by the delay time of the crankshaft signal is avoided, so that the performance of the engine is greatly improved, and the natural engine power, economy and emission become better, which indirectly improves the user experience and has a high practical value.

[0085] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0086] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation modes, which are merely illustrative rather than restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A method for determining an ignition advance angle, characterized in that: Applied to a first electronic control unit, the method comprises: Determine a target correction value of the ignition advance angle of the target cylinder according to the current engine speed, wherein the target correction value represents: an angle that the crankshaft rotates based on the current engine speed during a transmission time when the crankshaft position signal is transmitted from the second electronic control unit to the first electronic control unit; Determining a target ignition advance angle of the target cylinder according to the target correction value and an original ignition advance angle of the target cylinder; According to the current engine speed, a target correction value of the ignition advance angle of the target cylinder is determined, including: According to the current engine speed, a preset correction value curve is queried to determine the target correction value, wherein the correction value curve indicates a corresponding relationship between the engine speed and the correction value; The correction value curve is obtained by the following method: Determining the number of the flywheel teeth that the crankshaft rotates through during the delay time of the crankshaft position signal transmission according to the engine speed and the number of the flywheel teeth; According to the angle corresponding to each tooth in the flywheel teeth and the number of the flywheel teeth rotated by the crankshaft during the delay period, the angle of rotation of the crankshaft during the delay period is determined, and the angle is the correction value; The correction value curve is drawn with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate.

2. The method according to claim 1, characterized in that Determining a target ignition advance angle of the target cylinder according to the target correction value and the original ignition advance angle of the target cylinder includes: The sum of the original ignition advance angle of the target cylinder and the target correction value is determined as the target ignition advance angle of the target cylinder.

3. The method according to claim 1, characterized in that The crankshaft position signal is collected by a crankshaft position sensor and directly sent to the second electronic control unit; After receiving the crankshaft position signal, the second electronic control unit transmits the crankshaft position signal to the first electronic control unit; The transmission time of the crankshaft position signal from the second electronic control unit to the first electronic control unit is the delay time in the transmission process of the crankshaft position signal.

4. The method according to claim 3, characterized in that: The delay time is determined by a software filter coefficient in the second electronic control unit.

5. A device for determining an ignition advance angle, characterized in that: Applied to a first electronic control unit, the device comprises: a target correction value determination module, configured to determine a target correction value of an ignition advance angle of a target cylinder according to a current engine speed, wherein the target correction value represents: an angle that a crankshaft rotates based on the current engine speed during a transmission time when a crankshaft position signal is transmitted from a second electronic control unit to the first electronic control unit; A target ignition angle determination module, used to determine a target ignition advance angle of the target cylinder according to the target correction value and an original ignition advance angle of the target cylinder; The target correction value determination module is specifically used for: According to the current engine speed, a preset correction value curve is queried to determine the target correction value, wherein the correction value curve indicates a corresponding relationship between the engine speed and the correction value; The device further comprises: a correction value curve acquisition module, wherein the correction value curve acquisition module specifically comprises: A flywheel teeth number determination unit, used for determining the number of the flywheel teeth that rotate during the delay time according to the engine speed and the number of the flywheel teeth; A crankshaft rotation angle determination unit is used to determine the crankshaft rotation angle within the delay time according to the angle corresponding to each tooth in the flywheel teeth, the number of the flywheel teeth rotated per unit time, and the delay time, and take the negative value of the angle as the correction value; The curve drawing unit is used to draw the correction value curve with the engine speed as the horizontal coordinate and the correction value as the vertical coordinate.

6. A car, characterized in that: The automobile comprises: a first electronic control unit, a second electronic control unit and a crankshaft position sensor; The crankshaft position sensor collects the crankshaft position signal and directly sends it to the second electronic control unit; After receiving the crankshaft position signal, the second electronic control unit transmits the crankshaft position signal to the first electronic control unit; The first electronic control unit is used to execute the method for determining the ignition advance angle as described in any one of claims 1-4.

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