A method, device, vehicle and medium for controlling engine speed

Abstract

The present invention discloses a method, device, vehicle and medium for controlling engine speed. The method for controlling engine speed comprises: obtaining the current engine speed, the current temperature of engine oil and the current gear position of transmission in real time; determining the first maximum speed limit of the engine according to the current temperature; determining the second maximum speed limit of the engine according to the current gear position; determining the current speed deviation of the engine according to the first maximum speed limit, the second maximum speed limit and the current speed; judging whether the current speed deviation is greater than a first preset value, and activating the oil cut-off protection function of the engine if the current speed deviation is greater than the first preset value, that is, timely controlling the fuel injector of the engine to stop injecting fuel so that the engine stops working, thereby improving the safety of engine use, extending the service life of the engine, and achieving real-time adjustment of the current speed of the engine to improve the adjustment efficiency.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a method, device, vehicle and medium for controlling engine speed. Background Art

[0002] If the engine speed is not limited during driving, there may be a danger of engine overspeed. Engine overspeed will not only damage the engine body and its accessories, reducing their service life, but may also cause the vehicle to lose control and threaten the driver's life. Therefore, the engine speed must be limited according to its operating status.

[0003] In the prior art, from the perspective of the entire vehicle, the engine speed limit is calculated through the vehicle speed limit value and the transmission ratio of the transmission system, and the engine speed is directly limited to achieve the speed limit. This method does not take into account the maximum speed allowed under the current operating state of the engine, which is easy to reduce the service life of the engine, and the speed regulation efficiency is low. Summary of the invention

[0004] The present invention provides a method, device, vehicle and medium for controlling the speed of an engine, so as to improve the speed regulation efficiency, improve the safety of the engine and prolong the service life of the engine.

[0005] In a first aspect, the present invention provides a method for controlling an engine speed, comprising:

[0006] Get the current engine speed, current oil temperature and current gear position of the transmission in real time;

[0007] determining a first maximum speed limit of the engine according to the current temperature;

[0008] determining a second maximum speed limit of the engine according to the current gear position;

[0009] determining a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed;

[0010] Determining whether the current rotation speed deviation value is greater than a first preset value;

[0011] If yes, the fuel cut-off protection function of the engine is activated, and the process returns to the steps of obtaining the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time to determining whether the current speed deviation value is greater than the first preset value;

[0012] Wherein, the fuel cut-off protection function of the engine includes: controlling the fuel injector of the engine to stop injecting fuel.

[0013] Optionally, determining a current speed deviation value of the engine according to the first maximum speed limit, the second maximum speed limit and the current speed includes:

[0014] determining the smaller one of the first maximum speed limit value and the second maximum speed limit value as the maximum speed limit value of the engine;

[0015] A current speed deviation value of the engine is determined according to a difference between the current speed and the maximum speed limit.

[0016] Optionally, determining a first maximum speed limit of the engine according to the current temperature includes:

[0017] Acquire a first mapping relationship between engine oil temperature and maximum speed limit;

[0018] According to the first mapping relationship, a maximum speed limit value corresponding to the current temperature is determined as a first maximum speed limit value of the engine.

[0019] Optionally, determining a second maximum speed limit of the engine according to the current gear position includes:

[0020] Acquire a second mapping relationship between the transmission gear position and the maximum speed limit;

[0021] According to the second mapping relationship, a maximum speed limit value corresponding to the current gear position is determined as a second maximum speed limit value of the engine.

[0022] Optionally, the engine speed control method further includes:

[0023] If the current speed deviation value is less than or equal to the first preset value, the oil cut-off protection function of the engine is turned off, and the steps of obtaining the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time to determining whether the current speed deviation value is greater than the first preset value are returned.

[0024] Optionally, the engine speed control method further includes:

[0025] If the current rotation speed deviation value is less than or equal to the first preset value, determining whether the current rotation speed deviation value is greater than a second preset value;

[0026] If so, activating a torque limiting function of the engine;

[0027] After activating the torque limiting function of the engine, determining a proportional coefficient and an integral time according to the current speed and the current gear position;

[0028] Determining the maximum allowable output torque of the engine according to the current speed deviation value, the proportional coefficient and the integration time;

[0029] The current output torque of the engine is controlled to be limited to be less than or equal to a maximum allowable output torque.

[0030] Optionally, the engine speed control method further includes:

[0031] If the current speed deviation value is less than or equal to the second preset value, return to execute the steps of obtaining the current speed of the engine, the current temperature of the engine oil and the current gear of the transmission in real time to determine whether the current speed deviation value is greater than the first preset value.

[0032] In a second aspect, the present invention provides an engine speed control device, comprising:

[0033] A real-time information acquisition module is used to obtain the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission in real time;

[0034] a first maximum speed limit value determining module, configured to determine a first maximum speed limit value of the engine according to the current temperature;

[0035] a second maximum speed limit value determining module, configured to determine a second maximum speed limit value of the engine according to the current gear position;

[0036] a speed deviation value determining module, configured to determine a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed;

[0037] A judging module, used to judge whether the current rotation speed deviation value is greater than a first preset value;

[0038] The fuel cut-off protection function activation module is used to activate the fuel cut-off protection function when the current rotation speed deviation value is greater than a first preset value.

[0039] In a third aspect, the present invention provides a vehicle, comprising at least: an engine and a controller,

[0040] The controller is used to execute the engine speed control method described in the first aspect of the present invention.

[0041] In a fourth aspect, the present invention provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, wherein the computer instructions are used to enable a processor to implement the engine speed control method described in the first aspect of the present invention when executed.

[0042] The technical solution provided by the present invention determines the first maximum speed limit of the engine according to the current temperature and the second maximum speed limit of the engine according to the current gear after obtaining the current speed of the engine, the current temperature of the engine oil and the current gear of the transmission, so as to determine the current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed, and activates the fuel cut-off protection function of the engine when the current speed deviation value is greater than a first preset value, that is, promptly controls the engine's injector to stop injecting fuel, so that the engine stops working, thereby improving the engine's safety and extending the engine's service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 A flow chart of a method for controlling engine speed provided in Embodiment 1 of the present invention;

[0044] Figure 2 A flow chart of a method for controlling engine speed provided in Embodiment 2 of the present invention;

[0045] Figure 3 A flow chart of a method for controlling engine speed provided in Embodiment 3 of the present invention;

[0046] Figure 4 A flow chart of a method for controlling engine speed provided in Embodiment 4 of the present invention;

[0047] Figure 5 This is a schematic diagram of the structure of an engine speed control device provided in Embodiment 5 of the present invention. DETAILED DESCRIPTION

[0048] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0049] Embodiment 1

[0050] Figure 1 The flow chart of a method for controlling engine speed provided in the first embodiment of the present invention is applicable to the case of controlling engine speed. The method can be executed by the engine speed control device provided by the present invention, and the control device is implemented in the form of software and / or hardware. Figure 1 As shown, the method for controlling the engine speed includes:

[0051] S101. Acquire the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time.

[0052] The current speed of the engine refers to the speed of the engine in the current operating state.

[0053] Specifically, the current speed of the engine can be obtained through the crankshaft position sensor. The crankshaft position sensor can be set next to the pulley at the front end of the engine crankshaft bearing or next to the flywheel signal ring gear at the rear end of the crankshaft. The current temperature of the engine oil can be obtained through a temperature sensor, etc., and the current gear position of the transmission can be obtained through a gear position sensor, etc.

[0054] S102: Determine a first maximum speed limit of the engine according to the current temperature.

[0055] Specifically, different oil temperatures will result in different oil lubrication capabilities. At this time, once the engine speed exceeds the speed limit at the current oil temperature, the oil film will be overloaded and ruptured, and the oil lubrication capability will gradually be lost. The engine may experience cylinder scuffing or even jamming and other adverse conditions. Therefore, it is necessary to determine the first maximum speed limit under the current operating state of the engine according to the current temperature of the oil, so as to adjust the current speed of the engine according to the limit, prevent the engine from overspeeding and causing failures, and improve the operating safety of the engine.

[0056] In an optional embodiment, determining the first maximum speed limit of the engine based on the current temperature may specifically include: obtaining a first mapping relationship between the oil temperature and the maximum speed limit; and determining the maximum speed limit corresponding to the current temperature as the first maximum speed limit of the engine based on the first mapping relationship.

[0057] The first mapping relationship may be a curve diagram of the maximum speed limit and the oil temperature or a correspondence table of the maximum speed limit and the oil temperature, which may be obtained through experiments or experience.

[0058] Specifically, when the first mapping relationship is a curve diagram of the maximum speed limit and the oil temperature, after the current oil temperature of the oil is known, the curve diagram of the maximum speed limit and the oil temperature can be directly compared to determine the horizontal and vertical coordinate values ​​of the coordinate points on the curve diagram corresponding to the current oil temperature, and the maximum speed limit corresponding to the current oil temperature can be determined according to the horizontal and vertical coordinate values, and the maximum speed limit is determined as the first maximum speed limit of the engine. Alternatively, when the first mapping relationship is a corresponding table of the maximum speed limit and the oil temperature, after the current oil temperature of the oil is known, the maximum speed limit corresponding to the current oil temperature can be directly obtained by looking up the table, and the maximum speed limit is determined as the first maximum speed limit of the engine.

[0059] S103: Determine a second maximum speed limit of the engine according to the current gear position.

[0060] Among them, the gear position can affect the second maximum speed limit of the engine. The higher the gear position, the greater the second maximum speed limit of the engine, and the lower the gear position, the lower the second maximum speed limit of the engine.

[0061] Specifically, if the current speed of the engine exceeds the second maximum speed limit allowed by the current gear, the vehicle will become uneven, which will easily affect the driver's driving experience and increase fuel consumption. If the current speed of the engine exceeds the second maximum speed limit allowed by the current gear frequently, it will easily cause the gear meshing clearance of the transmission to increase and increase wear, causing the transmission and engine to be damaged prematurely, shortening the service life of the transmission and the engine. Therefore, it is necessary to determine the second maximum speed limit of the engine under the current operating state according to the current gear of the transmission, so as to adjust the current speed of the engine in time according to the limit, prevent the engine from overspeeding and causing damage to the engine and transmission, improve the operating safety of the engine, and extend the service life of the engine and the transmission.

[0062] In an optional embodiment, determining the second maximum speed limit of the engine according to the current gear may specifically include: obtaining a second mapping relationship between the transmission gear and the maximum speed limit; and determining the maximum speed limit corresponding to the current gear as the second maximum speed limit of the engine according to the second mapping relationship.

[0063] The second mapping relationship may be a curve diagram of the maximum speed limit and the transmission gear position or a correspondence table of the maximum speed limit and the transmission gear position, etc., which may be obtained through experiments or experience.

[0064] Specifically, when the second mapping relationship is a curve diagram of the maximum speed limit and the transmission gear position, after the current gear position of the transmission is known, the curve diagram of the maximum speed limit and the transmission gear position can be directly compared to determine the horizontal and vertical coordinate values ​​of the coordinate point on the curve diagram corresponding to the current gear position, and the maximum speed limit corresponding to the current gear position can be determined according to the horizontal and vertical coordinate values, and the maximum speed limit is determined as the second maximum speed limit of the engine. Alternatively, when the second mapping relationship is a correspondence table of the maximum speed limit and the transmission gear position, after the current gear position of the transmission is known, the maximum speed limit corresponding to the current gear position can be directly obtained by looking up the table, and the maximum speed limit is determined as the second maximum speed limit of the engine.

[0065] S104: Determine a current speed deviation value of the engine according to the first maximum speed limit, the second maximum speed limit and the current speed.

[0066] The current speed deviation value of the engine indicates the difference between the current speed and the maximum speed limit value currently allowed by the engine. The difference between the current speed and the first maximum speed limit value determined according to the current temperature of the engine oil is used as the current speed difference value of the engine; or the difference between the current speed and the second maximum speed limit value determined according to the current gear position of the transmission is used as the current speed difference value of the engine.

[0067] S105, determining whether the current rotation speed deviation value is greater than a first preset value; if so, executing S106.

[0068] The first preset value is a positive number greater than zero, and the value can be determined according to the actual use of the engine inside the vehicle, and the embodiment of the present invention does not make any specific limitation on this.

[0069] S106: Activate the fuel cut-off protection function of the engine.

[0070] Among them, the fuel cut-off protection function of the engine includes: controlling the fuel injector of the engine to stop injecting fuel.

[0071] Specifically, when the current speed deviation value of the engine is greater than zero, it indicates that the current speed of the engine has exceeded the maximum speed limit currently allowed by the engine, and when the current speed deviation value is greater than the first preset value, it indicates that the current speed has largely exceeded the maximum speed limit currently allowed by the engine. In this case, it is very easy to damage the engine and cause engine failure. At this time, the engine injector is promptly controlled to stop injecting fuel, so that the engine stops working, improves the safety of the engine, and prolongs the service life of the engine. Exemplarily, the first preset value is 200. If the current speed deviation value is greater than 200, the engine injector is controlled to stop injecting fuel.

[0072] In an optional embodiment, after activating the fuel cut-off protection function of the engine, the process returns to obtain the current engine speed, the current temperature of the engine oil and the current gear of the transmission. If the calculated current speed deviation value is still greater than the first preset value, the fuel cut-off protection function of the engine is still activated, and the process continues to return to obtain the current engine speed, the current temperature of the engine oil and the current gear of the transmission. In this process, the relationship between the current speed deviation value and the first preset value is cyclically obtained to activate the fuel cut-off protection function of the engine in time, adjust the current speed of the engine in real time, and improve the adjustment efficiency.

[0073] The technical solution provided by the embodiment of the present invention determines the first maximum speed limit of the engine according to the current temperature and the second maximum speed limit of the engine according to the current gear after obtaining the current speed of the engine, the current temperature of the engine oil and the current gear of the transmission, so as to determine the current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed, and activates the fuel cut-off protection function of the engine when the current speed deviation value is greater than a first preset value, that is, promptly controls the engine's injector to stop injecting fuel, so that the engine stops working, thereby improving the safety of engine use and extending the service life of the engine.

[0074] Embodiment 2

[0075] Figure 2 A flow chart of a method for controlling the engine speed provided in the second embodiment of the present invention is provided. Based on the above embodiment, the method describes the situation where the current speed deviation value is less than or equal to the first preset value, such as Figure 2 As shown, the method specifically includes:

[0076] S201. Acquire the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time.

[0077] S202: Determine a first maximum speed limit of the engine according to the current temperature.

[0078] S203: Determine a second maximum speed limit of the engine according to the current gear position.

[0079] S204: Determine a current speed deviation value of the engine according to the first maximum speed limit, the second maximum speed limit and the current speed.

[0080] S205, determine whether the current speed deviation value is greater than the first preset value; if so, execute S206; if not, execute S207.

[0081] S206: Activate the fuel cut-off protection function of the engine.

[0082] S207, turn off the fuel cut-off protection function of the engine, and return to execute each step from S201 to S205. Specifically, if the current speed deviation value is less than or equal to the first preset value, it indicates that the current speed of the engine has not reached the situation that causes damage or failure to the engine. At this time, there is no need to activate the fuel cut-off protection function of the engine, that is, turn off the fuel cut-off protection function of the engine, and control the fuel injector of the engine to spray fuel to the engine normally, so that the engine can run normally; at the same time, after turning off the fuel cut-off protection function of the engine, return to obtain the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission again. If the current speed deviation value after calculation is greater than the first preset value, activate the fuel cut-off protection function of the engine, and continue to return to the steps of obtaining the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission. If the current speed deviation value after calculation is less than or equal to the first preset value, turn off the fuel cut-off protection function of the engine. In this process, the size relationship between the current speed deviation value and the first preset value is cyclically obtained, so as to activate or turn off the fuel cut-off protection function of the engine in time, adjust the current speed of the engine in real time, and improve the adjustment efficiency.

[0083] The technical solution provided by the embodiment of the present invention determines in real time whether the current speed deviation value of the engine is greater than a first preset value. If the current speed deviation value is less than or equal to the first preset value, the fuel cut-off protection function of the engine is turned off in time to achieve normal fuel supply to the engine and put the engine into normal operating state. At the same time, after turning off the fuel cut-off protection function of the engine, it returns again to obtain the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission, so as to adjust the current speed of the engine in real time and improve the adjustment efficiency.

[0084] Real-time Example 3

[0085] Figure 3 A flow chart of a method for controlling an engine speed provided in Embodiment 3 of the present invention is provided. Based on the above embodiments, the method describes a case where a current speed deviation value of the engine is determined according to a first maximum speed limit value, a second maximum speed limit value and a current speed, such as Figure 3 As shown, the method specifically includes:

[0086] S301. Acquire the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time.

[0087] S302: Determine a first maximum speed limit of the engine according to the current temperature.

[0088] S303: Determine a second maximum speed limit of the engine according to the current gear position.

[0089] S304: Determine the smaller one of the first maximum speed limit value and the second maximum speed limit value as the maximum speed limit value of the engine.

[0090] Specifically, after obtaining the first maximum speed limit and the second maximum speed limit, the size relationship between the first maximum speed limit and the second maximum speed limit can be determined, so that when the second maximum speed limit is less than or equal to the first maximum speed limit, the smaller second maximum speed limit is determined as the maximum speed limit of the engine; when the first maximum speed limit is less than or equal to the second maximum speed limit, the smaller first maximum speed limit is determined as the maximum speed limit of the engine.

[0091] S305: Determine a current speed deviation value of the engine according to a difference between the current speed and the maximum speed limit.

[0092] The current speed deviation value of the engine is the difference between the current speed and the maximum speed limit. The speed deviation value can represent the difference between the current speed and the maximum speed limit, so as to adjust the current speed according to the difference.

[0093] S306, determine whether the current rotation speed deviation value is greater than the first preset value; if so, execute S307.

[0094] S307: Activate the fuel cut-off protection function of the engine.

[0095] In an embodiment of the present invention, after the smaller one of the first maximum speed limit and the second maximum speed limit is determined as the maximum speed limit of the engine, the current speed deviation value of the engine is determined according to the difference between the current speed and the maximum speed limit. Since the speed deviation value is determined according to the smaller one of the first maximum speed limit and the second maximum speed limit, when the current speed is adjusted according to the current speed deviation value, the engine can be protected in time and the operating safety of the engine can be improved.

[0096] Embodiment 4

[0097] Figure 4 A flow chart of a method for controlling engine speed provided in Embodiment 4 of the present invention is provided. Based on the above embodiments, the method describes the situation where the current speed deviation value is less than or equal to the first preset value, such as Figure 4 As shown, the method specifically includes:

[0098] S401. Acquire the current speed of the engine, the current temperature of the engine oil, and the current gear position of the transmission in real time.

[0099] S402: Determine a first maximum speed limit of the engine according to the current temperature.

[0100] S403: Determine a second maximum speed limit of the engine according to the current gear position.

[0101] S404: Determine a current speed deviation value of the engine according to the first maximum speed limit, the second maximum speed limit and the current speed.

[0102] S405, determine whether the current rotation speed deviation value is greater than the first preset value; if so, execute S406; if not, execute S407.

[0103] S406: Activate the fuel cut-off protection function of the engine.

[0104] S407, determine whether the current speed deviation value is greater than the second preset value; if so, execute S408; if not, return to execute each step from S401 to S405.

[0105] The second preset value is related to the current usage of the engine and / or transmission and can be set according to actual needs, and the embodiment of the present invention does not make any specific limitation to this.

[0106] Specifically, if the current speed deviation value is less than or equal to the first preset value and less than the second preset value, it indicates that the current speed will not cause damage to the engine and other components, that is, there is no need to execute the oil cut-off protection function or the torque function to protect the engine and other components. The process can be returned to execute the steps of obtaining the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission in real time to determine whether the current speed deviation value is greater than the first preset value, thereby realizing real-time adjustment of the current speed and improving the speed regulation efficiency.

[0107] S408: Activate the torque limiting function of the engine.

[0108] The torque limiting function refers to limiting the current output torque of the engine to achieve the effect of reducing the current engine speed.

[0109] Specifically, if the current speed deviation value of the engine is less than or equal to the first preset value and greater than the second preset value, it indicates that the current speed of the engine can be smoothly adjusted by the torque limiting function, thereby improving the driver's driving experience without using the fuel cut-off protection function.

[0110] S409: After activating the torque limiting function of the engine, determine the proportional coefficient and the integral time according to the current speed and the current gear position.

[0111] Among them, the proportional coefficient is determined by the engine speed and the gear of the transmission, the integral time is also determined by the engine speed and the gear of the transmission, the relationship between the proportional coefficient and the speed and gear can be reflected in the form of a graph or table, and the relationship between the integral time and the speed and gear can also be reflected in the form of a graph or table.

[0112] Specifically, the proportional coefficient and the integral time are determined according to the current rotation speed and the current gear position through a curve graph or a table.

[0113] S410: Determine the maximum allowable output torque of the engine according to the current speed deviation value, the proportional coefficient and the integration time.

[0114] The maximum allowable output torque of the engine is related to the current speed deviation value, the proportional coefficient and the integration time. Any change in the current speed deviation value, the proportional coefficient and the integration time will cause the maximum allowable output torque of the engine to change.

[0115] Specifically, the current speed deviation value, proportionality coefficient and integration time may be input into the PI controller, and the PI controller outputs the maximum allowable output torque of the engine according to the current speed deviation value, proportionality coefficient and integration time and internal operation logic.

[0116] S411. Control the current output torque of the engine to be limited to be less than or equal to the maximum allowable output torque.

[0117] Specifically, the current output torque of the engine may be limited to be less than or equal to the maximum allowable output torque by a device such as an engine controller, and this is not specifically limited in the embodiment of the present invention.

[0118] The technical solution of the embodiment of the present invention is that when the current speed deviation value is less than or equal to the first preset value, it continues to determine whether the current speed deviation value is greater than the second preset value. If the current speed deviation value is greater than the second preset value, the torque limit function of the engine is activated, and the proportional coefficient and the integral time are determined according to the current speed and the current gear. According to the current speed deviation value, the proportional coefficient and the integral time, the maximum allowable output torque of the engine is determined, and the current output torque limit of the engine is controlled to be less than or equal to the maximum allowable output torque, so as to achieve smooth adjustment of the current speed of the engine and improve the driving experience of the driver. If the current speed deviation value is less than or equal to the second preset value, it returns to execute the steps of obtaining the current speed of the engine, the current temperature of the engine oil and the current gear of the transmission in real time to determining whether the current speed deviation value is greater than the first preset value, so as to achieve real-time adjustment of the current speed and improve the speed adjustment efficiency.

[0119] Embodiment 5

[0120] Figure 5 FIG. 1 is a schematic diagram of a structure of an engine speed control device provided in Embodiment 5 of the present invention. The engine speed control device can be implemented in the form of hardware and / or software, such as Figure 5 As shown, the control device includes:

[0121] The real-time information acquisition module 11 is used to acquire the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission in real time;

[0122] A first maximum speed limit value determining module 12, configured to determine a first maximum speed limit value of the engine according to the current temperature;

[0123] A second maximum speed limit value determining module 13, used to determine a second maximum speed limit value of the engine according to the current gear position;

[0124] A speed deviation value determination module 14, configured to determine a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed;

[0125] A judging module 15 is used to judge whether the current speed deviation value is greater than a first preset value;

[0126] The fuel cut-off protection function activation module 16 is used to activate the fuel cut-off protection function when the current rotation speed deviation value is greater than a first preset value.

[0127] The engine speed control device provided in an embodiment of the present invention can execute the engine speed control method provided in any embodiment of the present invention, and has corresponding functional modules and beneficial effects of the execution method. The similarities can be referred to the above description.

[0128] Embodiment 6

[0129] Based on the same inventive concept, an embodiment of the present invention provides a vehicle, comprising at least: an engine and a controller, the controller is used to execute the control method for limiting the engine speed of any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method, and the same parts can be referred to the above description. .

[0130] Embodiment 7

[0131] An embodiment of the present invention provides a computer-readable storage medium, which stores computer instructions. The computer instructions are used to enable a processor to implement a control method for limiting the engine speed of any embodiment of the present invention when executed, and have the same beneficial effects as the method, which will not be repeated here.

[0132] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and that various obvious changes, readjustments, combinations and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for controlling engine speed, characterized in that: include: Get the current engine speed, current oil temperature and current gear position of the transmission in real time; determining a first maximum speed limit of the engine according to the current temperature; determining a second maximum speed limit of the engine according to the current gear position; determining a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed; Determining whether the current rotation speed deviation value is greater than a first preset value; If yes, activating the fuel cut-off protection function of the engine; The fuel cut-off protection function of the engine includes: controlling the fuel injector of the engine to stop injecting fuel; If the current speed deviation value is less than or equal to the first preset value, determining whether the current speed deviation value is greater than a second preset value; If so, activating a torque limiting function of the engine; After activating the torque limiting function of the engine, determining a proportional coefficient and an integral time according to the current speed and the current gear position; Determining the maximum allowable output torque of the engine according to the current speed deviation value, the proportional coefficient and the integration time; Controlling the current output torque of the engine to be limited to be less than or equal to the maximum allowable output torque; Determining a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed includes: determining the smaller one of the first maximum speed limit value and the second maximum speed limit value as the maximum speed limit value of the engine; A current speed deviation value of the engine is determined according to a difference between the current speed and the maximum speed limit.

2. The method for controlling the engine speed according to claim 1, characterized in that: Determining a first maximum speed limit of the engine according to the current temperature includes: Acquire a first mapping relationship between engine oil temperature and maximum speed limit; According to the first mapping relationship, a maximum speed limit value corresponding to the current temperature is determined as a first maximum speed limit value of the engine.

3. The method for controlling the engine speed according to claim 1, characterized in that: Determining a second maximum speed limit of the engine according to the current gear position includes: Acquire a second mapping relationship between the transmission gear position and the maximum speed limit; According to the second mapping relationship, a maximum speed limit value corresponding to the current gear position is determined as a second maximum speed limit value of the engine.

4. The method for controlling the engine speed according to claim 1, characterized in that: Also includes: If the current rotation speed deviation value is less than or equal to the second preset value, the process returns to the step of acquiring the current rotation speed of the engine, the current temperature of the engine oil and the current gear position of the transmission in real time.

5. A control device for engine speed, characterized in that: include: A real-time information acquisition module is used to obtain the current speed of the engine, the current temperature of the engine oil and the current gear position of the transmission in real time; a first maximum speed limit value determining module, configured to determine a first maximum speed limit value of the engine according to the current temperature; a second maximum speed limit value determining module, configured to determine a second maximum speed limit value of the engine according to the current gear position; a speed deviation value determining module, configured to determine a current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed; Determining the current speed deviation value of the engine according to the first maximum speed limit value, the second maximum speed limit value and the current speed, comprising: determining the smaller one of the first maximum speed limit value and the second maximum speed limit value as the maximum speed limit value of the engine; determining the current speed deviation value of the engine according to the difference between the current speed and the maximum speed limit value; A judging module, used to judge whether the current rotation speed deviation value is greater than a first preset value; A fuel cut-off protection function activation module is used to activate the fuel cut-off protection function when the current speed deviation value is greater than the first preset value; when the current speed deviation value is less than or equal to the first preset value, determine whether the current speed deviation value is greater than a second preset value; if so, activate the torque limiting function of the engine; after activating the torque limiting function of the engine, determine the proportional coefficient and the integral time according to the current speed and the current gear; determine the maximum allowable output torque of the engine according to the current speed deviation value, the proportional coefficient and the integral time; control the current output torque limit of the engine to be less than or equal to the maximum allowable output torque.

6. A vehicle, characterized in that: At least: Engine and controller, The controller is used to execute the engine speed control method according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the engine speed control method according to any one of claims 1 to 4 when executed.

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