P2 hybrid power tractor engine starting control method

Abstract

The invention provides a P2 hybrid power tractor engine starting control method which comprises the following steps: selecting an engine starting mode according to a mode selection condition; wherein the starting mode comprises a driving motor starting mode or a starter starting mode; judging whether the engine is successfully started; and if the first starting fails in the driving motor starting mode, restarting once to enter the starter starting mode under the condition that the vehicle is not powered off. According to the invention, the starting performance of the P2 hybrid traction vehicle is improved.

Description

Technical Field

[0001] The present application belongs to the field of engine starting control, and specifically relates to a method for starting a P2 hybrid tractor engine. Background Art

[0002] At present, automobile fuel consumption targets are becoming increasingly stringent, and traditional fuel vehicles are difficult to meet fuel consumption requirements. The P2 hybrid system is a technical solution widely used in hybrid vehicles. Figure 1 The basic information of the tractor power drive system shown is as follows: it is mainly composed of an engine (with a built-in starter), a transmission and a drive motor. The engine and the drive motor are connected by a clutch K0, which is a typical P2 hybrid system. The tractor power drive system is equipped with a starter and a drive motor. The output power and torque of the drive motor in a stable state are greater than those of the starter. The corresponding engine has two possible starting modes, namely the starter starting mode and the drive motor starting mode. For engineering tractors using diesel engines, the drive motor has good starting quietness and good fuel-saving performance (fast speed increase and short starting duration); while the starter has strong peak power generation and is easy to start. It can be used as a backup starting solution in special circumstances, and also realizes the function of starting the engine when the hybrid tractor is used in pure fuel mode.

[0003] The motor starting scheme used in the actual vehicle state is set by the vehicle control strategy. At present, the starting strategy of P2 hybrid tractors on the market focuses on fuel consumption performance. In extremely cold conditions, there are difficulties in starting or multiple operations under low temperature conditions to start normally. The user experience is poor and there is a need for improvement. Summary of the invention

[0004] The purpose of this application is to provide a P2 hybrid traction vehicle engine start control method, which can improve the starting performance of the P2 hybrid traction vehicle and enhance the user's driving experience.

[0005] The technical solution provided by this application is:

[0006] In a first aspect, the present application provides a P2 hybrid tractor engine starting control method, comprising: selecting an engine starting mode according to a mode selection condition; the starting mode includes a drive motor starting mode or a starter starting mode; judging whether the engine is started successfully; if the first start fails in the drive motor starting mode, restarting once to enter the starter starting mode without powering off the vehicle.

[0007] With this solution, when the vehicle is powered on, it will select the drive motor start mode or the starter start mode to start the engine based on the set mode selection conditions. If the first start fails in the drive motor start mode, the vehicle can enter the starter start mode by restarting once without powering off the vehicle. Because the peak power generation is strong, it can often reach the set speed value in a short time under the specified torque conditions, which is reflected in the successful engine start. This solution usually allows users to succeed in the second start under low temperature conditions. This can solve the problem of multiple failures to start under low temperature conditions.

[0008] In one possible implementation, the engine start mode is selected according to the mode selection conditions, including: when it is confirmed that the drive motor, inverter and battery inspection are normal, the battery SOC status, the forward drive power of the drive motor and the engine oil temperature meet the set conditions, select to enter the drive motor start mode.

[0009] Through this solution, when it is confirmed that the high-voltage components can be driven (the drive motor, inverter and battery are tested normally), the battery SOC status, the forward driving power of the drive motor and the engine oil temperature meet the set conditions, the drive motor start-up mode is selected to improve fuel saving performance and ensure quietness.

[0010] In one possible implementation, the determination of whether the engine is started successfully includes: adopting a torque control mode when the drive motor is started, and determining that the start is successful if the engine speed reaches a set value within a specified time under a given torque target value, otherwise determining that the start fails.

[0011] With this solution, the torque control mode is used when the drive motor is started. A successful start is defined as the engine speed reaching the set value within a specified time under a given torque target value. However, when the outside temperature is low, the resistance of the oil in the transmission and differential device will increase as the temperature decreases. The engine sometimes cannot reach the speed target value within the specified time and will be judged as a failed start, which is reflected in the engine being unable to start under low temperature conditions. Multiple starts in this setting mode may also be invalid. At this time, if the first start fails in the drive motor start mode, restarting once to enter the starter start mode without powering off the vehicle can improve the starter start performance.

[0012] In a possible implementation, in the starter starting mode, the clutch K0 connecting the engine and the drive motor is disconnected.

[0013] Under normal starting conditions, the clutch K0 is in a closed state. The above scheme disconnects the clutch K0 under starter starting mode, which can avoid the influence of the oil resistance inside the transmission and differential at the rear end of the clutch when the engine is started at idle speed (this resistance usually increases with decreasing temperature), and can further improve the starting performance of the starter under low temperature conditions.

[0014] In a possible implementation, if a start fails in the drive motor starting mode, the following operations are performed:

[0015] The engine oil temperature and the drive motor torque target value at this time are automatically recorded, and the drive motor torque target value when the vehicle is restarted after power is turned off at the corresponding engine oil temperature is set to increase the preset value based on the drive motor torque target value at this time.

[0016] In a possible implementation, the preset value is 50 NM.

[0017] With this solution, in the drive motor start mode, if a start fails, the engine oil temperature and the drive motor torque target value (program control) at this time are automatically recorded. The drive motor torque target value automatically increases by a preset value when the vehicle is powered off and restarted. If it still fails, it is accumulated each time after power off and restart, and the drive motor torque target value (corresponding to the engine oil temperature) is recorded when the final successful start is made. The torque target value of the successful start is used for the next start, which can improve the vehicle's one-time start performance in the drive motor mode under low temperature conditions and ensure a one-time start in the drive motor mode. Among them, recording the engine oil temperature can be used to determine whether to choose the drive motor mode or the starter mode at the next start, and is also used to record and select the motor torque target value corresponding to each engine oil temperature.

[0018] In one possible implementation, if the drive motor starting mode is selected when the ambient temperature is lower than a certain threshold (extremely low temperature condition), and the engine still fails to start after the drive motor torque target value is increased to the peak torque of the drive motor, the engine oil temperature threshold in the mode selection condition is added so that when the ambient temperature is lower than a certain threshold, the starter starting mode is entered at the first start.

[0019] Because the peak torque of the drive motor has a certain limit, if the peak torque of the drive motor is increased under extremely low temperature conditions and it still cannot start, this application adopts the following solution: modify (add) the engine oil temperature threshold in the mode selection condition, so that the starter start mode is entered at the first start under extremely low temperature conditions, ensuring one-time starting performance.

[0020] In a second aspect, the present application provides an electronic device, including: a memory and a processor;

[0021] The memory is used to store computer programs;

[0022] The processor is used to call the computer program to execute the method as described above.

[0023] In a third aspect, the present application provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed on an electronic device, the electronic device implements the method as described above.

[0024] In a fourth aspect, the present application provides a computer program product, including a computer program, and when the computer program is executed on an electronic device, the electronic device implements the method as described above.

[0025] The specific implementation methods of the second to fourth aspects of the present application can refer to the implementation methods of the first aspect, which will not be repeated here.

[0026] Beneficial effects:

[0027] This application improves the starting performance of the P2 hybrid traction vehicle and enhances the user's driving experience by setting a linkage control strategy for the drive motor and the starter. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the structure of the P2 hybrid power system;

[0029] Figure 2 This is an engine starting flow chart in an embodiment of the present application;

[0030] Figure 3 This is an engine starting flow chart in an embodiment of the present application. DETAILED DESCRIPTION

[0031] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.

[0032] The present application provides a P2 hybrid tractor engine start control method, comprising the following steps:

[0033] According to the mode selection condition, an engine starting mode is selected; the starting mode includes a drive motor starting mode or a starter starting mode;

[0034] The drive motor refers to the drive motor in the power drive system of the P2 hybrid tractor; the starter refers to the starter in the power drive system of the P2 hybrid tractor;

[0035] In some embodiments, the engine start mode is selected according to the mode selection conditions, including: when it is confirmed that the drive motor, inverter and battery inspection are normal, the battery SOC status, the forward drive power of the drive motor and the engine oil temperature meet the set conditions, select to enter the drive motor start mode.

[0036] Determine whether the engine is started successfully; if the first start fails in the drive motor starting mode, restart once without powering off the vehicle to enter the starter starting mode.

[0037] In some embodiments, the above-mentioned determination of whether the engine is started successfully includes: adopting a torque control mode when the drive motor is started, and determining that the start is successful if the engine speed reaches a set value within a specified time under a given torque target value, otherwise determining that the start fails.

[0038] In some embodiments, in the starter starting mode, the clutch K0 connecting the engine and the drive motor is disconnected.

[0039] In some embodiments, if a start fails in the drive motor start mode, the following operations are also performed:

[0040] The engine oil temperature and the drive motor torque target value at this time are automatically recorded, and the drive motor torque target value when the vehicle is restarted after power is turned off at the corresponding engine oil temperature is set to increase the preset value based on the drive motor torque target value at this time.

[0041] In some embodiments, the preset value is 50 NM.

[0042] In some embodiments, if the drive motor starting mode is selected when the ambient temperature is lower than a certain threshold, and the engine still fails to start after the drive motor torque target value increases to the peak torque of the drive motor, the engine oil temperature threshold is added to the mode selection condition so that when the ambient temperature is lower than a certain threshold, the starter starting mode is entered at the first start.

[0043] The embodiment of the present application also provides an electronic device, including: a memory and a processor;

[0044] The memory is used to store computer programs;

[0045] The processor is used to call the computer program to execute the method as described above.

[0046] An embodiment of the present application further provides a computer-readable storage medium, in which a computer program is stored. When the computer program is executed on an electronic device, the electronic device implements the method as described above.

[0047] An embodiment of the present application further provides a computer program product, including a computer program. When the computer program is executed on an electronic device, the electronic device implements the method as described above.

[0048] The embodiments of the present application also provide a system, an electronic device, a computer-readable storage medium, and a computer program product. The specific implementation methods can refer to the specific embodiments of the above methods and will not be repeated here.

[0049] Obviously, those skilled in the art should understand that the above-mentioned units or steps of the present application can be implemented by a general-purpose computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. In this way, the present application is not limited to any specific combination of hardware and software.

[0050] The above description of the embodiments of the present application is only a partial embodiment of the present application, which is used to enable professionals in the field to implement or use the content of the present application, and is not used to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A P2 hybrid tractor engine start control method, characterized in that: include: According to the mode selection condition, an engine starting mode is selected; the starting mode includes a drive motor starting mode or a starter starting mode; Determine whether the engine is started successfully; If the first start fails in the drive motor start mode, restart once to enter the starter start mode without powering off the vehicle.

2. The method according to claim 1, characterized in that The engine start mode is selected according to the mode selection conditions, including: when it is confirmed that the drive motor, inverter and battery inspection are normal, the battery SOC state, the forward driving power of the drive motor and the engine oil temperature meet the set conditions, select to enter the drive motor start mode.

3. The method according to claim 1, characterized in that The determination of whether the engine is started successfully includes: adopting a torque control mode when the drive motor is started, and determining that the start is successful if the engine speed reaches a set value within a specified time under a given torque target value, otherwise determining that the start fails.

4. The method according to claim 1, characterized in that In the starter starting mode, the clutch K0 connecting the engine and the drive motor is disconnected.

5. The method according to claim 1, characterized in that If the start fails in the drive motor starting mode, do the following: The engine oil temperature and the drive motor torque target value at this time are automatically recorded, and the drive motor torque target value when the vehicle is restarted after power is turned off at the corresponding engine oil temperature is set to increase the preset value based on the drive motor torque target value at this time.

6. The method according to claim 5, characterized in that The preset value is 50NM.

7. The method according to claim 5, characterized in that If the drive motor starting mode is selected when the ambient temperature is lower than a certain threshold, and the engine still fails to start after the drive motor torque target value is increased to the peak torque of the drive motor, the engine oil temperature threshold in the mode selection condition is increased so that the starter starting mode is entered at the first start when the ambient temperature is lower than a certain threshold.

8. An electronic device, characterized in that: include: Memory and processor; The memory is used to store computer programs; The processor is configured to call the computer program to execute the method according to any one of claims 1 to 7.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed on an electronic device, the electronic device implements the method according to any one of claims 1 to 7.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed on an electronic device, the electronic device implements the method according to any one of claims 1 to 7.

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