Calibration method for engine stop position and stop method

Abstract

The invention relates to an engine stop position calibration method and a stop method. The calibration of the stop position of the engine comprises the following steps: driving a crankshaft of the engine to rotate in response to the stop state of the engine; in the process that the crankshaft rotates from the initial angle to the preset angle, the angle change rate of the crankshaft is determined every first preset duration, and an angle change rate set is obtained; determining at least two target change rates from the angle change rate set, and determining target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold; and according to the target angle set, a stop position set of the engine is determined. By means of the method, the position where the starting resistance of the engine is small can be determined, the torque of the engine in the next starting process is reduced, starting energy consumption is reduced, meanwhile, it is guaranteed that the engine can be rapidly and smoothly started in the next starting process, noise and vibration in the engine stopping and starting process are reduced, and the comfort of the whole vehicle is improved.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a method for calibrating an engine stop position and a method for stopping the engine. Background Art

[0002] When the battery power of an extended-range electric vehicle drops to a preset threshold, the built-in range extender in the vehicle starts to charge the battery, thereby extending the vehicle's range. When the range extender is running, the engine in the range extender starts, driving the generator to rotate and generate electricity. If the engine is not stopped at a position with less starting resistance when it stops, the generator needs a larger torque to drag the engine, and it will generate vibration and noise, affecting driving comfort. Therefore, a method for calibrating the engine stop position is urgently needed to determine the stop position with less resistance in the engine. Summary of the invention

[0003] Based on this, a method for calibrating an engine stop position and a method for stopping the engine are provided to solve the problem in the prior art that the engine cannot be stopped at a position with less starting resistance.

[0004] In a first aspect, a method for calibrating an engine stop position is provided, the method comprising:

[0005] In response to the engine being in a stopped state, driving a crankshaft of the engine to rotate;

[0006] In the process of the crankshaft rotating from the initial angle to the preset angle, determining the angle change rate of the crankshaft at intervals of a first preset time length to obtain an angle change rate set;

[0007] Determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold;

[0008] A stop position set of the engine is determined according to the target angle set.

[0009] Optionally, in response to the engine being in a stopped state, driving the crankshaft of the engine to rotate comprises:

[0010] In response to the engine being in a stopped state, a crankshaft driving the engine rotates clockwise and counterclockwise, respectively.

[0011] Optionally, determining at least two target change rates from the angle change rate set includes:

[0012] Divide the rotation angle interval into at least two sub-intervals according to a preset rule; the rotation angle interval indicates a range from the initial angle to the preset angle;

[0013] Determine the angle change rate corresponding to each subinterval from the angle change rate set;

[0014] The angle change rate that is greater than the change rate threshold is determined as the target change rate, thereby obtaining at least two target change rates.

[0015] Optionally, dividing the rotation angle interval into at least two sub-intervals according to a preset rule includes:

[0016] Dividing the rotation angle interval into at least two first sub-intervals according to a first rule; the preset rule includes the first rule;

[0017] The rotation angle interval is divided into at least two second sub-intervals according to a second rule; the preset rule includes the second rule, and the first rule and the first rule are separated by a preset difference angle.

[0018] Optionally, determining a target angle corresponding to the target change rate includes:

[0019] In response to the difference between the first angle and the second angle being not greater than a first threshold, the first angle is determined as the target angle; wherein the first angle is the angle corresponding to the target change rate in the first sub-interval, and the second angle is the angle corresponding to the target change rate in the second sub-interval.

[0020] Optionally, determining a target angle corresponding to the target change rate includes:

[0021] In response to the difference between the third angle and the fourth angle being less than a second threshold value, and the angle change rate corresponding to the third angle being greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle; the second threshold value is greater than the first threshold value; wherein the third angle and the fourth angle are angles corresponding to the target change rate in the first sub-interval, or the third angle and the fourth angle are angles corresponding to the target change rate in the second sub-interval;

[0022] In response to the difference between the third angle and the fourth angle being smaller than the second threshold, and the angle change rate corresponding to the fourth angle being larger than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle.

[0023] Optionally, the calibration method further includes:

[0024] During the process of the crankshaft rotating from an initial angle to a preset angle, in response to the angle of the crankshaft remaining unchanged within a second preset time period, the position of the crankshaft is determined as a resistance position; the resistance position indicates that the resistance encountered by the crankshaft at the resistance position is greater than the preset resistance.

[0025] In a second aspect, a method for stopping an engine is provided, the method comprising:

[0026] In response to the engine being in a stopped state, determining a current position of a crankshaft of the engine;

[0027] According to the current position, determining a target parking position from a parking position set; the target parking position is spaced from the current position by less than a first preset distance, and the parking position set is obtained according to the calibration method described in the first aspect;

[0028] In response to the presence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, and the absence of the resistance position during the process of the crankshaft rotating from the current position to the target position, driving the crankshaft to rotate to the target position; the resistance position is obtained according to the calibration method described in the first aspect;

[0029] Wherein, the parking position set includes the target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates from the current position to the target parking position in relative directions.

[0030] Optionally, the shutdown method further includes:

[0031] In response to the absence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, the crankshaft is driven to rotate to the target stop position.

[0032] In a third aspect, a system for calibrating an engine stop position is provided, the calibration system comprising:

[0033] A first driving module, configured to drive the crankshaft of the engine to rotate in response to the engine being in a stopped state;

[0034] A first determining module is used to determine the angle change rate of the crankshaft at intervals of a first preset time length during the process of the crankshaft rotating from an initial angle to a preset angle, so as to obtain an angle change rate set;

[0035] A second determination module is used to determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold;

[0036] The third determination module is used to determine a stop position set of the engine according to the target angle set.

[0037] In a fourth aspect, a shutdown system of an engine is provided, the shutdown system comprising:

[0038] a fourth determination module, configured to determine a current position of a crankshaft of the engine in response to the engine being in a shutdown state;

[0039] a fifth determination module, configured to determine a target parking position from a parking position set according to the current position; the target parking position is spaced from the current position by less than a first preset distance, and the parking position set is obtained according to the calibration system described in the third aspect;

[0040] a second driving module, configured to drive the crankshaft to rotate to the target position in response to the presence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position and the absence of the resistance position during the process of the crankshaft rotating from the current position to the target position; the resistance position is obtained according to the calibration system described in the third aspect;

[0041] The stop position set includes the target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates to the target stop position in relative directions.

[0042] In a fifth aspect, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, wherein when the processor executes the computer program, the method described in the first aspect or the second aspect is implemented.

[0043] According to a sixth aspect, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the method described in the first aspect or the second aspect is implemented.

[0044] According to a seventh aspect, a computer program product is provided, comprising a computer program, wherein when the computer program is executed by a processor, the method described in the first aspect or the second aspect is implemented.

[0045] On the basis of conforming to the common sense in the art, the above-mentioned preferred conditions can be arbitrarily combined to obtain the preferred embodiments of the present application.

[0046] The above-mentioned calibration method and shutdown method of the engine stop position determine the angle change rate of the crankshaft at each first preset time interval during the process of the crankshaft rotating from the initial angle to the preset angle, determine the target change rate greater than the change rate threshold from the angle change rate, and obtain the engine stop position set according to the target angle corresponding to the target change rate. The position with the smaller starting resistance of the engine is determined by the target change rate, the torque of the engine is reduced when it is started next time, the energy consumption of the start is reduced, and at the same time, it is ensured that the engine can be started quickly and smoothly when it is started next time, the frustration during the engine shutdown and start process is reduced, and the comfort of the whole vehicle is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 is a flow chart of a method for calibrating an engine stop position in one embodiment;

[0048] Figure 2 A schematic flow chart of a method for stopping an engine in one embodiment;

[0049] Figure 3 is a structural schematic diagram of a system for calibrating an engine stop position in one embodiment;

[0050] Figure 4 is a schematic structural diagram of an engine shutdown system in one embodiment;

[0051] Figure 5 FIG. 1 is a schematic diagram of the structure of an electronic device in an embodiment. DETAILED DESCRIPTION

[0052] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0053] It should be noted that the diagram provided in the present embodiment only illustrates the basic concept of the present application in a schematic manner, so the diagram only shows the components related to the present application rather than drawing according to the number, shape and size of the components during actual implementation. The type, quantity and ratio of each component during actual implementation can be a random change, and its component layout type may also be more complicated. The structure, ratio, size, etc. illustrated by the accompanying diagram of this specification are only used to match the content disclosed in the specification, so that people familiar with this technology can understand and read, and are not used to limit the restrictive conditions that can be implemented in this application, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that can be produced by this application and the purpose that can be achieved, should still fall within the scope that the technical content disclosed in this application can cover. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are also only for the convenience of narration, rather than for limiting the scope that can be implemented in this application. The change or adjustment of its relative relationship, without substantial change of technical content, should also be regarded as the scope that can be implemented in this application.

[0054] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the text does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0055] As shown in this document, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "include" and "comprise" only indicate that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0056] The definitions of inclusion in this document, such as the terms "having", "may have", "include" or "may include" used herein, indicate the existence of the corresponding functions, operations, elements, etc. herein, and do not limit the existence of one or more other functions, operations, elements, etc. In addition, it should be understood that the terms "including" or "having" used herein indicate the existence of the features, numbers, steps, operations, elements, components, or a combination thereof described in the specification, without excluding the existence or addition of one or more other features, numbers, steps, operations, elements, components, or a combination thereof.

[0057] In the embodiments of the present application, prefixes such as "first" and "second" are used only to distinguish different description objects, and have no limiting effect on the position, order, priority, quantity or content of the described objects. The use of prefixes such as ordinal numbers to distinguish description objects in the embodiments of the present application does not constitute a limitation on the described objects. For the statement of the described objects, please refer to the description in the context of the claims or embodiments, and no unnecessary limitation should be constituted due to the use of such prefixes. In addition, in the description of the present embodiment, unless otherwise specified, the meaning of "multiple" is two or more.

[0058] Figure 1 A method for calibrating an engine stop position is provided for an exemplary embodiment of the present application, and the calibration method includes:

[0059] S11. In response to the engine being in a stopped state, driving the crankshaft of the engine to rotate.

[0060] The extended-range electric vehicle adds a range extender to the pure electric vehicle. When the battery power of the vehicle drops to the preset threshold, the built-in range extender in the vehicle starts to start and charge the battery, thereby extending the vehicle's range. The range extender includes an engine and a generator. When the range extender is running, the engine starts and drives the generator to rotate and generate electricity. Part of the generated electricity is directly supplied to the motor to maintain the normal driving of the vehicle, and the other part is stored in the battery, thereby extending the vehicle's range. If the engine is not stopped at a position with less starting resistance when it is shut down, the resistance when the engine is started is large, and the generator needs more torque to drag the engine, and it will generate vibration and noise, affecting driving comfort. The engine can be stopped at a position with less resistance to engine starting to make it easier to start the engine and reduce noise and vibration.

[0061] In order to determine the position of the engine with the least starting resistance in the clockwise and counterclockwise directions to ensure that the engine can be started quickly and smoothly the next time it is started, in one embodiment, in response to the engine being in a stopped state, driving the crankshaft of the engine to rotate includes:

[0062] In response to the engine being in a stopped state, a crankshaft driving the engine rotates clockwise and counterclockwise, respectively.

[0063] When the engine is in a shutdown state, the generator is controlled to be in a torque control mode. In the torque control mode, the generator base torque is used as input to drive the engine to rotate. Different generator base torques can be selected according to different engines and hybrid powertrains. Taking a four-stroke engine as an example, the judgment condition for determining the base torque is to rotate the crankshaft angle of the engine by 720° and the rotation time is between 60s and 80s, so that the engine remains in a state of rotation but with a low average speed. For example, the base torque can be 4N·m, 6N·m, 8N·m, 10N·m, etc. Different base torques are selected according to the engines of different vehicles. For example, 6N·m is selected in the embodiment of the present application, and 6N·m is used to continuously drive the engine to rotate forward and reversely for a complete power stroke respectively. The forward rotation can be clockwise rotation, and the reverse rotation can be counterclockwise rotation. Taking a four-stroke engine as an example, the crankshaft rotates 720° for a complete power stroke, and the generator drives the crankshaft of the engine to rotate 720° clockwise and counterclockwise respectively. The crankshaft that drives the engine rotates clockwise and counterclockwise respectively, which can determine the position with smaller starting resistance in the clockwise and counterclockwise directions respectively, ensuring that the engine can start quickly and smoothly at the next start, reducing the frustration during engine shutdown and starting, and improving the comfort of the entire vehicle.

[0064] If the engine crankshaft does not change within a certain period of time, such as 3 seconds, when the generator drives the engine with the basic torque, the torque is increased by 1N·m until the engine crankshaft angle changes or the engine crankshaft angle starts to rotate. When the engine crankshaft angle changes, the torque increased by the generator is written in, so that the torque driving the engine returns to the basic torque.

[0065] S12. When the crankshaft rotates from an initial angle to a preset angle, determine the angle change rate of the crankshaft at every first preset time interval to obtain an angle change rate set.

[0066] The initial angle is the initial position of the crankshaft, which may be the position of the crankshaft rotating 0°. The preset angle is set according to the actual situation, for example, the position after the crankshaft rotates 720°, 1080°, etc.

[0067] The first preset duration is set according to actual conditions, for example, it can be 5ms, 10ms, etc.

[0068] The generator drives the engine to rotate. During the process of the engine crankshaft rotating from an initial angle to a preset angle, the engine crankshaft angle signal can be collected at every first preset time interval based on sensors, such as a magnetic induction crankshaft position sensor, a Hall effect crankshaft position sensor, and a signal wheel tooth detection system, and the angle change rate of the engine crankshaft is calculated to obtain an angle change rate set consisting of at least two angle change rates.

[0069] S13. Determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set.

[0070] The target change rate is greater than a preset change rate threshold, and the change rate threshold is set according to actual conditions.

[0071] The target angle set includes at least two target angles, and the target angle indicates the angle of the crankshaft when the angle change rate of the crankshaft rotation is the target change rate. The target angle can be calculated based on the first preset time length and the target change rate. For example, the angle of the crankshaft rotation within the first preset time length can be calculated based on the product of the first preset time length and the target change rate, and then the angle is accumulated with the previous rotation angle of the crankshaft to obtain the target angle; the previous rotation angle of the crankshaft can be obtained by sequentially accumulating the product of the first preset time length and the angle change rate when the crankshaft starts to rotate from the initial angle.

[0072] When the target change rate is greater than the change rate threshold, it can be determined that the resistance of the crankshaft at the target angle corresponding to the target change rate is smaller. If the crankshaft of the engine stays at the target angle corresponding to the target change rate, the resistance of the engine at the next start will be smaller and the required torque will also be smaller, which can reduce the energy consumption of starting. The engine can start quickly and smoothly, reduce noise and vibration during engine starting, and improve the comfort of the entire vehicle.

[0073] In one embodiment, determining at least two target change rates from the set of angle change rates includes:

[0074] Divide the rotation angle interval into at least two sub-intervals according to a preset rule; the rotation angle interval indicates a range from an initial angle to a preset angle;

[0075] Determine the angle change rate corresponding to each subinterval from the angle change rate set;

[0076] The angle change rate that is greater than the change rate threshold is determined as the target change rate, and at least two target change rates are obtained.

[0077] Among them, the initial angle is the initial position of the crankshaft, which can be the position where the crankshaft rotates 0°. The preset angle is set according to the actual situation, for example, it is the position after the crankshaft rotates 720°, 1080°, etc. The rotation angle range can be composed of the angles of the crankshaft rotating clockwise and counterclockwise in a complete power stroke. Taking a four-stroke engine as an example, a crankshaft rotation of 720° is a complete power stroke. When the engine rotates clockwise and counterclockwise respectively, the crankshaft can first rotate clockwise from 0° to 720°, and then rotate counterclockwise back to 0°. The clockwise rotation angle range can be (0°, 720°), and the counterclockwise rotation angle range can be (720°, 0°). The rotation angle range is composed of the angle ranges of clockwise and counterclockwise rotation.

[0078] The preset rule is set according to the actual situation. For example, starting from the initial angle, the rotation angle intervals are divided into 90° intervals and the rotation angle intervals are divided into 180° intervals.

[0079] After the rotation angle interval is divided into at least two sub-intervals according to a preset rule, each sub-interval includes at least two angle change rates, and the angle change rate greater than the change rate threshold in each sub-interval is determined as the target change rate, and at least two target change rates can be obtained. For example, according to the preset rule of dividing the rotation angle interval at intervals of 90° starting from the initial angle, the rotation angle interval is divided into at least two sub-intervals, namely (0°, 180°), (180°, 360°), (360°, 540°), (540°, 720°), (720°, 540°), (540°, 360°), (360°, 180°), (180°, 0°).

[0080] Among them, (0°, 180°), (180°, 360°), (360°, 540°), (540°, 720°) are subintervals obtained after the crankshaft rotates clockwise, and (720°, 540°), (540°, 360°), (360°, 180°), (180°, 0°) are subintervals obtained after the crankshaft rotates counterclockwise. It can be understood that the target change rate determined according to the subinterval obtained after the crankshaft rotates clockwise indicates the position with less resistance when the crankshaft rotates clockwise, and the target change rate determined according to the subinterval obtained after the crankshaft rotates counterclockwise indicates the position with less resistance when the crankshaft rotates counterclockwise.

[0081] First, multiple angle change rates corresponding to the rotation angle in each sub-interval are determined from the angle change rate set, and then, from the multiple angle change rates in each sub-interval, the angle change rate greater than the change rate threshold is determined as the target change rate to obtain at least two target change rates. For example, the maximum angle change rate in each sub-interval can be determined as the target change rate.

[0082] The rotation angle interval is divided into sub-intervals according to preset rules, and then the angle change rate that is greater than the change rate threshold is determined as the target change rate from the multiple angle change rates in each sub-interval. This can obtain the position with less resistance in a complete working stroke of the crankshaft, so that the resistance at the next start of the engine can be smaller, and the required torque can also be smaller, which can reduce the energy consumption of starting, enable the engine to start quickly and smoothly, reduce noise and vibration during engine starting, and improve the comfort of the entire vehicle.

[0083] In one embodiment, the rotation angle is divided into at least two sub-intervals according to a preset rule, including:

[0084] Dividing the rotation angle interval into at least two first sub-intervals according to a first rule; the preset rule includes the first rule;

[0085] The rotation angle interval is divided into at least two second sub-intervals according to a second rule; the preset rule includes the second rule, and the first rule and the second rule are separated by a preset difference angle.

[0086] The first rule may be to start from the initial angle, divide the rotation angle interval at 90° intervals, and divide the rotation angle interval at 180° intervals. The second rule may be to start from the difference angle, divide the rotation angle interval at intervals, and divide the rotation angle interval at 180° intervals. The difference angle is set according to the actual situation, for example, it may be 45°, 60°, etc. It can be understood that the overall deviation between the second sub-interval and the first sub-interval is the difference angle.

[0087] For example, the first rule may be to start from 0° and divide the rotation angle interval into 180° intervals, so that the first sub-interval is (0°, 180°), (180°, 360°), (360°, 540°), (540°, 720°), (720°, 540°), (540°, 360°), (360°, 180°), (180°, 0°); the second rule may be to start from 45° and divide the rotation angle interval into 180° intervals, so that the second sub-interval is (45°, 225°), (225°, 405°), (405°, 585°), (585°, 45°), (45°, 585°), (585°, 405°), (405°, 225°), (225°, 45°). Among them, (0°, 180°), (180°, 360°), (360°, 540°), (540°, 720°) and (45°, 225°), (225°, 405°), (405°, 585°) are sub-intervals obtained after the crankshaft rotates clockwise, and (720°, 540°), (540°, 360°), (360°, 180°), (180°, 0°) and (45°, 585°), (585°, 405°), (405°, 225°), (225°, 45°) are sub-intervals obtained after the crankshaft rotates counterclockwise. It can be understood that the target change rate determined according to the sub-interval obtained after the crankshaft rotates clockwise indicates the position with less resistance when the crankshaft rotates clockwise, and the target change rate determined according to the sub-interval obtained after the crankshaft rotates counterclockwise indicates the position with less resistance when the crankshaft rotates counterclockwise.

[0088] First, multiple angle change rates corresponding to the rotation angles in each first subinterval and the second subinterval are determined from the angle change rate set, and then, from the multiple angle change rates in each first subinterval and the second subinterval, an angle change rate greater than a change rate threshold is determined as a target change rate to obtain at least two target change rates, for example, the maximum angle change rate in each subinterval can be determined as the target change rate. It can be understood that there is a target change rate in (0°, 180°) of the first subinterval, a target change rate in (180°, 360°), and so on.

[0089] The rotation angle interval is divided into multiple sub-intervals according to the first rule and the second rule, and the target change rate in each sub-interval is determined respectively. Based on the target change rate obtained in the second rule, it can be verified whether the angle corresponding to the target change rate in the first rule is the position with less resistance when the crankshaft rotates, thereby improving the accuracy of determining the position with less resistance.

[0090] In one embodiment, determining a target angle corresponding to a target change rate includes:

[0091] In response to the difference between the first angle and the second angle being greater than a first threshold, the first angle is determined as a target angle; wherein the first angle is an angle corresponding to a target change rate in a first subinterval, and the second angle is an angle corresponding to a target change rate in a second subinterval.

[0092] The first threshold is set according to actual conditions, for example, it can be 2°, 4°, 6°, etc.

[0093] Determine the target change rate in each first sub-interval and the second sub-interval respectively, and compare the angles corresponding to the target change rates in the first sub-interval and the second sub-interval. The angle corresponding to the target change rate in the first sub-interval is the first angle, and the angle corresponding to the target change rate in the second sub-interval is the second angle. If the difference between the first angle and the second angle is not greater than the first threshold, it is determined that the first angle and the second angle are the same angle, and the first angle is determined as the target angle. If the difference between the first angle and the second angle is greater than the first threshold, compare the angle change rates corresponding to the first angle and the second angle. If the angle change rate corresponding to the first angle is greater than the angle change rate corresponding to the second angle, the first angle is determined as the target angle. If the angle change rate corresponding to the second angle is greater than the angle change rate corresponding to the first angle, the second angle is determined as the target angle.

[0094] Based on the angle change rate corresponding to the second angle, it can be verified whether the angle corresponding to the angle change rate corresponding to the first angle is a position with less resistance when the crankshaft rotates, thereby improving the accuracy of determining the position with less resistance.

[0095] In one embodiment, determining a target angle corresponding to a target change rate includes:

[0096] In response to the difference between the third angle and the fourth angle being less than the second threshold, and the angle change rate corresponding to the third angle being greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle; the second threshold is greater than the first threshold; wherein the third angle and the fourth angle are angles corresponding to the target change rate in the first subinterval;

[0097] In response to the difference between the third angle and the fourth angle being less than the second threshold, and the angle change rate corresponding to the fourth angle being greater than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle.

[0098] The second threshold is set according to actual conditions, for example, it can be 45°, 50°, 90°, etc.

[0099] When the difference between the third angle and the fourth angle is less than the second threshold, and the third angle and the fourth angle are angles in the first subinterval, it is determined that the third angle and the fourth angle are angles obtained by segmentation according to the same rule, that is, the first rule, and the third angle is the position with less resistance corresponding to clockwise rotation, and the fourth angle is the position with less resistance corresponding to counterclockwise rotation. If the difference between the third angle and the fourth angle is less than the second threshold, and the angle change rate corresponding to the third angle is greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle, that is, the position with less resistance corresponding to clockwise rotation is determined as the target angle of the crankshaft. For example, if the difference between 102° clockwise rotation and 114° counterclockwise rotation is less than the second threshold, and the angle change rate corresponding to 102° clockwise rotation is greater than the angle change rate corresponding to 114° counterclockwise rotation, 102° clockwise rotation is determined as the target angle.

[0100] If the difference between the third angle and the fourth angle is less than the second threshold, and the angle change rate corresponding to the fourth angle is greater than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle, that is, the position with less resistance corresponding to counterclockwise rotation is determined as the target angle of the crankshaft.

[0101] In one embodiment, in response to the difference between the third angle and the fourth angle being less than the second threshold value, and the angle change rate corresponding to the third angle being greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle; the second threshold value is greater than the first threshold value; the third angle and the fourth angle are angles corresponding to the target change rate in the second sub-interval;

[0102] In response to the difference between the third angle and the fourth angle being less than the second threshold, and the angle change rate corresponding to the fourth angle being greater than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle.

[0103] The second threshold is set according to actual conditions, for example, it can be 45°, 50°, 90°, etc.

[0104] When the difference between the third angle and the fourth angle is less than the second threshold value, and the third angle and the fourth angle are angles in the second subinterval, it is determined that the third angle and the fourth angle are angles obtained by segmentation according to the same rule, that is, the second rule, and the third angle is the position with less resistance corresponding to clockwise rotation, and the fourth angle is the position with less resistance corresponding to counterclockwise rotation. If the difference between the third angle and the fourth angle is less than the second threshold value, and the angle change rate corresponding to the third angle is greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle, that is, the position with less resistance corresponding to clockwise rotation is determined as the target angle of the crankshaft. If the difference between the third angle and the fourth angle is less than the second threshold value, and the angle change rate corresponding to the fourth angle is greater than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle, that is, the position with less resistance corresponding to counterclockwise rotation is determined as the target angle of the crankshaft.

[0105] S14. Determine a stop position set of the engine according to the target angle set.

[0106] The target angle set includes at least two target angles, the target angle is the angle of rotation of the crankshaft corresponding to the target change rate in a complete working stroke, and the target change rate is greater than the preset change rate threshold, indicating that the rotation speed of the crankshaft in the target angle corresponding to the target change rate is faster. It can be understood that when the crankshaft is at the target angle, the resistance to the rotation of the crankshaft is small.

[0107] It is understandable that the stop position when the crankshaft rotates clockwise and counterclockwise may be inconsistent. For example, in a complete working stroke, the crankshaft rotation angle corresponding to the target change rate is 462° clockwise, then the target angle is 462° clockwise, and the position after the crankshaft rotates clockwise by the target angle is the optimal stop position of the engine, which can also be understood as the position with less resistance when the engine is started. Alternatively, in a complete working stroke, the crankshaft rotation angle corresponding to the target change rate is 480° counterclockwise, then the target angle is 480° counterclockwise, and the position after the crankshaft rotates counterclockwise by the target angle is the optimal stop position of the engine, which can also be understood as the position with less resistance when the engine is started.

[0108] By controlling the engine's shutdown position, it can be ensured that the engine can start quickly and smoothly the next time it is started, reducing noise and vibration during engine shutdown and startup, and improving the comfort of the entire vehicle.

[0109] Each cylinder of a multi-cylinder engine completes the power stroke in a certain order. For example, a four-stroke engine includes four-cylinder, six-cylinder, eight-cylinder, etc. Each cylinder undergoes the intake, compression, power, and exhaust strokes in sequence. In order to make the engine run smoothly, the four cylinders do not perform the same stroke at the same time, but work in a certain order. The crankshaft will also have different resistances in the working strokes of different cylinders. The resistance is the largest in the power stroke. Since there are four cylinders, there may be four locations with large resistance in a complete working stroke of the crankshaft.

[0110] Therefore, in order to determine the position of the engine with greater resistance, avoid the engine from stopping at the position of greater resistance, reduce the torque of the engine when it is started next time, and reduce the energy consumption of starting, in one embodiment, the calibration method also includes:

[0111] During the process of the crankshaft rotating from an initial angle to a preset angle, in response to the crankshaft angle remaining unchanged within a second preset time period, the position of the crankshaft is determined as a resistance position; the resistance position indicates that the resistance encountered by the crankshaft at the resistance position is greater than the preset resistance.

[0112] The second preset time length is set according to actual conditions, for example, 0.1s, 0.2s, or 0.5s.

[0113] The preset resistance can be set according to the actual situation.

[0114] When the engine is running and the crankshaft is rotating, there is a situation where the crankshaft cannot rotate and needs to be rotated by increasing the torque. Then, the position of the crankshaft when the crankshaft angle does not change for a period longer than a second preset period during the process of the engine crankshaft rotating from the initial angle to the preset angle is determined, and the position of the crankshaft at this time is determined as the resistance position, indicating that the resistance when the crankshaft rotates is greater than the preset resistance. If the engine stops at this position, the resistance encountered next time it is started is relatively large.

[0115] It is understandable that the resistance position when the crankshaft rotates clockwise and counterclockwise may be inconsistent. For example, in a complete working stroke of the crankshaft, when the crankshaft rotates 187° clockwise, the time length during which the crankshaft angle does not change is greater than the second preset time length, then the position at which the crankshaft rotates 187° clockwise is determined as the positive resistance position. For another example, in a complete working stroke of the crankshaft, when the crankshaft rotates 343° counterclockwise, the time length during which the crankshaft angle does not change is greater than the second preset time length, then the position at which the crankshaft rotates 343° counterclockwise is determined as the reverse resistance position. Taking a four-stroke engine as an example, when the engine rotates clockwise, there may be 4 resistance positions, and when it rotates counterclockwise, there may be 4 resistance positions, and the resistance positions corresponding to clockwise and counterclockwise rotations are inconsistent. The specific resistance positions of different engines are obtained based on actual calibration.

[0116] Determining the position of the engine with the greatest resistance and avoiding the engine from stopping at the position with the greatest resistance can reduce the torque when the engine is started next time and reduce the energy consumption during starting.

[0117] Corresponding to the calibration method of the engine stop position, as shown in Figure 2 As shown, an exemplary embodiment of the present application further provides a method for stopping an engine, the method comprising:

[0118] S21. In response to the engine being in a stopped state, determining a current position of a crankshaft of the engine.

[0119] When the range extender is shut down, if the engine speed is lower than 10rpm / min (speed change rate is 10 revolutions per minute) and the engine operation state is stopping or stop, and the crankshaft angle does not change within 0.1s, it is determined that the engine is in the shutdown state. At this time, the current position of the engine crankshaft is determined to determine whether the current position is the optimal shutdown position of the engine.

[0120] S22. Determine a target parking position from a parking position set according to the current position.

[0121] The stop position set is obtained according to the calibration method of the engine stop position in the above embodiment. The target stop position is less than the first preset distance from the current position, and the first preset distance is set according to the actual situation.

[0122] When the engine is completely stopped, a target stop position whose distance from the current position is less than a first preset distance is determined from the stop position set. It can be understood that the target stop position indicates the stop position closest to the current position.

[0123] S23, in response to the presence of a resistance position during the crankshaft rotating from the current position to the target stop position and the absence of a resistance position during the crankshaft rotating from the current position to the target position, driving the crankshaft to rotate to the target position.

[0124] The resistance position is obtained according to the calibration method of the engine stop position in the above embodiment.

[0125] The stop position set includes a target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates to the target stop position in relative directions.

[0126] If the target stop position closest to the current position is the stop position obtained by clockwise rotation, that is, the position with less resistance obtained by clockwise rotation, it indicates that when starting at the target stop position, it is necessary to rotate clockwise to achieve the effect of minimum resistance. If the target stop position closest to the current position is the stop position obtained by counterclockwise rotation, that is, the position with less resistance obtained by counterclockwise rotation, it indicates that when starting at the target stop position, it is necessary to rotate counterclockwise to achieve the effect of less resistance.

[0127] If the target stop position closest to the current position is a stop position obtained by clockwise rotation, and there is a resistance position in the process of the crankshaft rotating clockwise from the current position to the target stop position, but there is no resistance position in the process of the crankshaft rotating counterclockwise from the current position to the target position, it is determined to adjust the crankshaft angle counterclockwise to drive the crankshaft to the target position. It can be understood that if the target stop position closest to the current position is a stop position obtained by clockwise rotation, and there is a resistance position in the process of the crankshaft rotating clockwise from the current position to the target stop position, it is determined whether there is a resistance position at a position with less resistance in the counterclockwise direction. If not, the crankshaft is driven to avoid the resistance position and rotate the crankshaft counterclockwise to a position with less resistance when rotating counterclockwise, that is, the target position.

[0128] Correspondingly, if the target stopping position closest to the current position is the stopping position obtained by counterclockwise rotation, there is a resistance position in the process when the crankshaft rotates counterclockwise from the current position to the target stopping position, but there is no resistance position in the process when the crankshaft rotates clockwise from the current position to the target position, then it is determined to adjust the crankshaft angle clockwise to drive the crankshaft to rotate to the target position.

[0129] After the crankshaft angle adjustment direction is determined, the torque is loaded from 0 to the target torque that can drive the engine at a certain torque slope. The torque slope is obtained according to the actual calibration. When the crankshaft angle is close to the target position, for example, the angle difference between the crankshaft and the target position is less than 12°, the torque slope is slowly reduced to make the engine crankshaft angle stop within a range of one tooth before and after the target position. When the crankshaft angle is adjusted and the crankshaft angle does not change within 0.5s, it is determined that the crankshaft has stabilized and the engine has completed shutdown.

[0130] Stopping the engine at a position with less resistance ensures that the engine can start quickly and smoothly the next time it is started, reduces noise and vibration during engine shutdown and starting, and improves the comfort of the entire vehicle.

[0131] In one embodiment, the shutdown method further includes:

[0132] In response to the absence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, the crankshaft is driven to rotate to the target stop position.

[0133] If the target stop position closest to the current position is the stop position obtained by clockwise rotation, and there is no resistance position in the process of the crankshaft rotating clockwise from the current position to the target stop position, it is determined to adjust the crankshaft angle clockwise to drive the crankshaft to rotate to the target stop position.

[0134] If the target stop position closest to the current position is the stop position obtained by counterclockwise rotation, and there is no resistance position during the process of the crankshaft rotating counterclockwise from the current position to the target stop position, it is determined to adjust the crankshaft angle counterclockwise to drive the crankshaft to rotate to the target stop position.

[0135] After the crankshaft angle adjustment direction is determined, the torque is loaded from 0 to the target torque that can drive the engine at a certain torque slope. The torque slope is obtained according to the actual calibration. When the crankshaft angle is close to the target position, for example, the angle difference between the crankshaft and the target position is less than 12°, the torque slope is slowly reduced to make the engine crankshaft angle stop within a range of one tooth before and after the target position. When the crankshaft angle is adjusted and the crankshaft angle does not change within 0.5s, it is determined that the crankshaft has stabilized and the engine has completed shutdown.

[0136] It should be understood that although Figure 1-2 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1-2 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0137] like Figure 3 As shown, the embodiment of the present application further provides a calibration system for an engine stop position, the calibration system comprising:

[0138] A first driving module 31, configured to drive the crankshaft of the engine to rotate in response to the engine being in a stopped state;

[0139] A first determining module 32 is used to determine the angle change rate of the crankshaft at intervals of a first preset time length during the process of the crankshaft rotating from an initial angle to a preset angle, so as to obtain an angle change rate set;

[0140] A second determination module 33 is used to determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold;

[0141] The third determination module 34 is used to determine a stop position set of the engine according to the target angle set.

[0142] In one embodiment, the first driving module 31 is further used for:

[0143] In response to the engine being in a stopped state, a crankshaft driving the engine rotates clockwise and counterclockwise, respectively.

[0144] In one embodiment, the second determining module 33 is further configured to:

[0145] Divide the rotation angle interval into at least two sub-intervals according to a preset rule; the rotation angle interval indicates a range from the initial angle to the preset angle;

[0146] Determine the angle change rate corresponding to each subinterval from the angle change rate set;

[0147] The angle change rate that is greater than the change rate threshold is determined as the target change rate, thereby obtaining at least two target change rates.

[0148] In one embodiment, the second determining module 33 is further configured to:

[0149] Dividing the rotation angle interval into at least two first sub-intervals according to a first rule; the preset rule includes the first rule;

[0150] The rotation angle interval is divided into at least two second sub-intervals according to a second rule; the preset rule includes the second rule, and the first rule and the first rule are separated by a preset difference angle.

[0151] In one embodiment, the second determining module 33 is further configured to:

[0152] In response to the difference between the first angle and the second angle being not greater than a first threshold, the first angle is determined as the target angle; wherein the first angle is the angle corresponding to the target change rate in the first sub-interval, and the second angle is the angle corresponding to the target change rate in the second sub-interval.

[0153] In one embodiment, the second determining module 33 is further configured to:

[0154] In response to the difference between the third angle and the fourth angle being less than a second threshold value, and the angle change rate corresponding to the third angle being greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle; the second threshold value is greater than the first threshold value; wherein the third angle and the fourth angle are angles corresponding to the target change rate in the first sub-interval, or the third angle and the fourth angle are angles corresponding to the target change rate in the second sub-interval;

[0155] In response to the difference between the third angle and the fourth angle being smaller than the second threshold, and the angle change rate corresponding to the fourth angle being larger than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle.

[0156] In one embodiment, the calibration system further includes a sixth determination module, configured to:

[0157] During the process of the crankshaft rotating from an initial angle to a preset angle, in response to the angle of the crankshaft remaining unchanged within a second preset time period, the position of the crankshaft is determined as a resistance position; the resistance position indicates that the resistance encountered by the crankshaft at the resistance position is greater than the preset resistance.

[0158] like Figure 4 As shown, the embodiment of the present application further provides an engine shutdown system, the shutdown system comprising:

[0159] A fourth determination module 41 is used to determine a current position of a crankshaft of the engine in response to the engine being in a shutdown state;

[0160] A fifth determination module 42 is used to determine a target parking position from a parking position set according to the current position; the target parking position is less than a first preset distance from the current position, and the parking position set is obtained according to the above-mentioned calibration system;

[0161] A second driving module 43 is configured to drive the crankshaft to rotate to the target position in response to the presence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position and the absence of the resistance position during the process of the crankshaft rotating from the current position to the target position; the resistance position is obtained according to the calibration system;

[0162] Wherein, the parking position set includes the target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates from the current position to the target parking position in relative directions.

[0163] In one embodiment, the shutdown system further includes a third driving module, configured to:

[0164] In response to the absence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, the crankshaft is driven to rotate to the target stop position.

[0165] For the system embodiment, since it basically corresponds to the method embodiment, the relevant parts can refer to the partial description of the method embodiment. The system embodiment described above is only illustrative, wherein the units described as separate components may or may not be physically separated, and the components as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the present application solution.

[0166] Figure 5 This is a schematic diagram of the structure of an electronic device shown in an example embodiment of the present application. The electronic device includes a memory, a processor, and a computer program stored in the memory and used to run on the processor. When the processor executes the computer program, the method described in any of the above embodiments is implemented. Figure 5 The electronic device 50 shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0167] like Figure 5 As shown, the electronic device 50 may be in the form of a general-purpose computing device, for example, it may be a server device. The components of the electronic device 50 may include, but are not limited to: at least one processor 51, at least one memory 52, and a bus 53 connecting different system components (including the memory 52 and the processor 51).

[0168] The bus 53 includes a data bus, an address bus, and a control bus.

[0169] The memory 52 may include a volatile memory, such as a random access memory (RAM) 521 and / or a cache memory 522 , and may further include a read-only memory (ROM) 523 .

[0170] The memory 52 may also include a program tool 525 (or utility) having a set (at least one) of program modules 524, such program modules 524 including but not limited to: an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment.

[0171] The processor 51 executes various functional applications and data processing by running the computer program stored in the memory 52, such as the method provided in any of the above embodiments.

[0172] The electronic device 50 may also communicate with one or more external devices 54 (e.g., keyboards, pointing devices, etc.). Such communication may be performed via an input / output (I / O) interface 55. Furthermore, the electronic device 50 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 56. As shown, the network adapter 56 communicates with other modules of the electronic device 50 via a bus 53. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 50, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID (disk array) systems, tape drives, and data backup storage systems, etc.

[0173] It should be noted that although several units / modules or sub-units / modules of the electronic device are mentioned in the above detailed description, this division is merely exemplary and not mandatory. In fact, according to the embodiments of the present application, the features and functions of two or more units / modules described above can be embodied in one unit / module. Conversely, the features and functions of one unit / module described above can be further divided into multiple units / modules to be embodied.

[0174] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, and when the program is executed by a processor, the method provided in any of the above embodiments is implemented.

[0175] The readable storage medium may include but is not limited to: a portable disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical storage device, a magnetic storage device or any suitable combination of the above.

[0176] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0177] An embodiment of the present application further provides a computer program product, including a computer program, which implements any of the above methods when executed by a processor.

[0178] Among them, the program code for executing the computer program product of the present application can be written in any combination of one or more programming languages, and the program code can be executed completely on the user device, partially on the user device, as an independent software package, partially on the user device and partially on a remote device, or completely on the remote device.

[0179] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0180] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A method for calibrating an engine stop position, characterized in that: The calibration method comprises: In response to the engine being in a stopped state, driving a crankshaft of the engine to rotate; In the process of the crankshaft rotating from the initial angle to the preset angle, determining the angle change rate of the crankshaft at intervals of a first preset time length to obtain an angle change rate set; Determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold; A stop position set of the engine is determined according to the target angle set.

2. The calibration method according to claim 1, characterized in that: In response to the engine being in a stopped state, driving the crankshaft of the engine to rotate comprises: In response to the engine being in a stopped state, a crankshaft driving the engine rotates clockwise and counterclockwise, respectively.

3. The calibration method according to claim 1, characterized in that: The determining at least two target change rates from the angle change rate set comprises: Divide the rotation angle interval into at least two sub-intervals according to a preset rule; the rotation angle interval indicates a range from the initial angle to the preset angle; Determine the angle change rate corresponding to each subinterval from the angle change rate set; The angle change rate that is greater than the change rate threshold is determined as the target change rate, thereby obtaining at least two target change rates.

4. The calibration method according to claim 3, characterized in that: The step of dividing the rotation angle interval into at least two sub-intervals according to a preset rule includes: Dividing the rotation angle interval into at least two first sub-intervals according to a first rule; the preset rule includes the first rule; The rotation angle interval is divided into at least two second sub-intervals according to a second rule; the preset rule includes the second rule, and the first rule and the first rule are separated by a preset difference angle.

5. The calibration method according to claim 4, characterized in that: The determining the target angle corresponding to the target change rate includes: In response to the difference between the first angle and the second angle being not greater than a first threshold, the first angle is determined as the target angle; wherein the first angle is the angle corresponding to the target change rate in the first sub-interval, and the second angle is the angle corresponding to the target change rate in the second sub-interval.

6. The calibration method according to claim 4, characterized in that: The determining the target angle corresponding to the target change rate includes: In response to the difference between the third angle and the fourth angle being less than a second threshold value, and the angle change rate corresponding to the third angle being greater than the angle change rate corresponding to the fourth angle, the third angle is determined as the target angle; the second threshold value is greater than the first threshold value; wherein the third angle and the fourth angle are angles corresponding to the target change rate in the first sub-interval, or the third angle and the fourth angle are angles corresponding to the target change rate in the second sub-interval; In response to the difference between the third angle and the fourth angle being smaller than the second threshold, and the angle change rate corresponding to the fourth angle being larger than the angle change rate corresponding to the third angle, the fourth angle is determined as the target angle.

7. The calibration method according to any one of claims 1 to 6, characterized in that: The calibration method further comprises: During the process of the crankshaft rotating from an initial angle to a preset angle, in response to the angle of the crankshaft remaining unchanged within a second preset time period, the position of the crankshaft is determined as a resistance position; the resistance position indicates that the resistance encountered by the crankshaft at the resistance position is greater than the preset resistance.

8. A method for stopping an engine, characterized in that: The shutdown method comprises: In response to the engine being in a stopped state, determining a current position of a crankshaft of the engine; According to the current position, determining a target parking position from a parking position set; the target parking position is spaced from the current position by less than a first preset distance, and the parking position set is obtained according to the calibration method according to any one of claims 1 to 7; In response to the presence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, and the absence of the resistance position during the process of the crankshaft rotating from the current position to the target position, driving the crankshaft to rotate to the target position; the resistance position is obtained according to the calibration method according to claim 7; Wherein, the parking position set includes the target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates from the current position to the target parking position in relative directions.

9. The shutdown method according to claim 8, characterized in that: The shutdown method further comprises: In response to the absence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position, the crankshaft is driven to rotate to the target stop position.

10. A system for calibrating an engine stop position, characterized in that: The calibration system comprises: A first driving module, configured to drive the crankshaft of the engine to rotate in response to the engine being in a stopped state; A first determining module is used to determine the angle change rate of the crankshaft at intervals of a first preset time length during the process of the crankshaft rotating from an initial angle to a preset angle, so as to obtain an angle change rate set; A second determination module is used to determine at least two target change rates from the angle change rate set, and determine the target angles corresponding to the target change rates to obtain a target angle set; the target change rate is greater than a preset change rate threshold; The third determination module is used to determine a stop position set of the engine according to the target angle set.

11. An engine shutdown system, characterized in that: The shutdown system comprises: a fourth determination module, configured to determine a current position of a crankshaft of the engine in response to the engine being in a shutdown state; a fifth determination module, configured to determine a target parking position from a parking position set according to the current position; the target parking position is spaced from the current position by less than a first preset distance, and the parking position set is obtained according to the calibration system according to claim 10; a second driving module, configured to drive the crankshaft to rotate to the target position in response to the presence of a resistance position during the process of the crankshaft rotating from the current position to the target stop position and the absence of the resistance position during the process of the crankshaft rotating from the current position to the target position; the resistance position is obtained from the calibration system according to claim 10; The stop position set includes the target position, the target position is spaced from the current position by less than a second preset distance, and the crankshaft rotates from the current position to the target position and rotates to the target stop position in relative directions.

12. An electronic device comprising a memory, a processor, and a computer program stored in the memory and used to run on the processor, characterized in that: When the processor executes the computer program, the method according to any one of claims 1 to 9 is implemented.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 9 is implemented.

14. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the method according to any one of claims 1 to 9 is implemented.

Images