Clutch sliding friction fault judgment method, control device, vehicle and computer program product

Abstract

The embodiment of the invention provides a clutch sliding friction fault judgment method, a control device, a vehicle and a computer program product, and the method comprises the steps: obtaining a rotating speed signal communication state between a driving motor and the control device and between an engine and the control device in the process that the vehicle is driven by hybrid power; the rotating speed signal communication state comprises a communication normal state and a communication abnormal state; based on the rotating speed signal communication state, target rotating speed parameters of the vehicle are obtained, and based on the target rotating speed parameters, the rotating speed difference between the driving end and the driven end of the clutch is determined; the target rotating speed parameters comprise any two of a generator rotating speed, a driving motor rotating speed, a wheel rotating speed and an engine rotating speed; and according to the magnitude relation between the rotating speed difference and a preset rotating speed difference threshold value, a sliding friction fault judgment result of the clutch is obtained. And the sliding friction fault of the clutch can be accurately identified under the condition of normal communication or abnormal communication.

Description

Technical Field

[0001] The present application relates to the technical field of hybrid electric vehicles, and in particular to a clutch slip fault judgment method, a control device, a vehicle and a computer program product. Background Art

[0002] At present, with the increasing electrification of automobile transmissions, hybrid transmissions have gradually become mainstream. For traditional transmissions, the clutch system is involved in the realization of many functions such as vehicle starting, gear shifting, torque transmission, etc., and is a very important component of the transmission. However, compared with traditional transmissions, the starting process and gear shifting process of hybrid transmissions are completed by motors. The clutch mainly plays the function of torque transmission and disconnection. The clutch no longer has the ability to slip, so the definition and diagnosis method of clutch slip faults have also changed. With the further increase in the market share of hybrid transmissions, the diagnosis of clutch slip faults has become more important. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a clutch slip fault judgment method, a control device, a vehicle and a computer program product to achieve the technical effect of accurately diagnosing the clutch slip fault in a hybrid transmission.

[0004] In a first aspect, an embodiment of the present application provides a clutch slip fault judgment method, the method being applied to a control device in a hybrid vehicle; the hybrid vehicle comprising a clutch, an engine, a drive motor, and a generator; the method comprising:

[0005] During the driving of the vehicle by hybrid power, the speed signal communication status between the drive motor and the engine and the control device is obtained; the speed signal communication status includes a normal communication status and an abnormal communication status;

[0006] Based on the speed signal communication state, a target speed parameter of the vehicle is obtained, and based on the target speed parameter, a speed difference between the driving end and the driven end of the clutch is determined; the target speed parameter includes any two of the generator speed, the drive motor speed, the wheel speed, and the engine speed;

[0007] According to the magnitude relationship between the rotation speed difference and a preset rotation speed difference threshold, a slip fault determination result of the clutch is obtained.

[0008] In the above implementation process, by monitoring the communication status of the speed signal and selecting appropriate target speed parameters to calculate the speed difference, the slip fault of the clutch can be accurately identified regardless of whether the communication is normal or abnormal.

[0009] Furthermore, the hybrid vehicle further comprises a hydraulic control system; and before acquiring the communication state of the speed signal between the drive motor and the engine and the control device, further comprises:

[0010] Determine that the clutch meets the target condition; the target condition includes: any one or more of: the clutch is in a locked state, the clutch has no self-learning action, and the hydraulic control system has no leakage fault.

[0011] In the above implementation process, by ensuring that the clutch is in a specific state and that the hydraulic system has no leakage fault, the influence of external factors on the diagnosis result can be reduced and the accuracy of sliding fault judgment can be improved.

[0012] Further, acquiring a target speed parameter of the vehicle based on the speed signal communication state, and determining a speed difference between an active end and a driven end of the clutch based on the target speed parameter, includes:

[0013] Based on the speed signal communication state, acquiring the target speed parameter and the target speed ratio;

[0014] Based on the target speed parameter and the target speed ratio, a speed difference between the driving end and the driven end of the clutch is determined.

[0015] In the above implementation process, different speed parameters and speed ratios are selected according to the communication status, so that the clutch status can be accurately determined in different situations.

[0016] Further, the first speed signal communication state between the drive motor and the control device, and the second speed signal communication state between the engine and the control device are both in normal communication state;

[0017] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0018] Acquiring the engine speed and the drive motor speed as the target speed parameter;

[0019] Obtaining a first speed ratio, where the first speed ratio is a ratio between a speed of the driving motor and a speed of the driven end;

[0020] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0021] Determine the engine speed as the active end speed of the active end, and determine the driven end speed of the driven end according to the drive motor speed and the first speed ratio;

[0022] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0023] In the above implementation process, when the speed signal communication status between the drive motor and the engine and the control device is normal, the engine speed and the drive motor speed are selected as the target speed parameters, and the first speed ratio (the ratio between the drive motor speed and the driven end speed) is determined. Based on the target speed parameter and the first speed ratio, the speed difference between the active end and the driven end of the clutch is calculated. By monitoring the speed signal communication status and selecting a suitable speed parameter when the communication is normal, the accuracy of sliding fault judgment is improved.

[0024] Further, the first speed signal communication state between the drive motor and the control device is a normal communication state, and the second speed signal communication state between the engine and the control device is an abnormal communication state;

[0025] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0026] Acquiring the generator speed and the drive motor speed as the target speed parameters;

[0027] Obtaining a first speed ratio and a second speed ratio; the first speed ratio is the ratio between the rotation speed of the driving motor and the rotation speed of the driven end; the second speed ratio includes any one of the ratio between the rotation speed of the engine and the rotation speed of the generator, and the ratio between the rotation speed of the generator and the rotation speed of the active end of the clutch;

[0028] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0029] The active end speed of the active end is determined according to the generator speed and the second speed ratio; the driven end speed of the driven end is determined according to the drive motor speed and the first speed ratio; and the difference between the active end speed and the driven end speed is determined as the speed difference.

[0030] In the above implementation process, the accuracy of sliding fault judgment is improved by monitoring the communication status of the speed signal and selecting the generator speed and the drive motor speed as the target speed parameters when the engine communication is abnormal.

[0031] Further, the first speed signal communication state between the drive motor and the control device is a communication abnormal state, and the second speed signal communication state between the engine and the control device is a communication normal state;

[0032] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0033] Acquiring the engine speed and the wheel speed as the target speed parameters;

[0034] Obtaining a third speed ratio; the third speed ratio is a ratio between the rotation speed of the wheel end and the rotation speed of the driven end of the clutch;

[0035] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0036] Determine the engine speed as the active end speed of the active end, and determine the driven end speed of the driven end according to the wheel speed and the third speed ratio;

[0037] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0038] In the above implementation process, by monitoring the communication status of the speed signal, and selecting the engine speed and wheel speed as the target speed parameters when the drive motor communication is abnormal, the speed difference of the clutch is determined in combination with the third speed ratio, and then it is determined whether the clutch has a slip failure.

[0039] Further, the first speed signal communication state between the drive motor and the control device is a communication abnormal state, and the second speed signal communication state between the engine and the control device is a communication abnormal state;

[0040] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0041] Acquiring the generator speed and the wheel speed as the target speed parameters;

[0042] Obtaining a second speed ratio and a third speed ratio; the second speed ratio includes any one of a ratio between the engine speed and the generator speed, and a ratio between the generator speed and the clutch driving end speed; the third speed ratio is a ratio between the wheel end speed and the clutch driven end speed;

[0043] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0044] Determining an active end speed of the active end according to the generator speed and the second speed ratio;

[0045] determining a driven end speed of the driven end according to the wheel speed and the third speed ratio;

[0046] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0047] In the above implementation process, when the communication between the drive motor and the engine is abnormal, the generator speed and the wheel speed are selected as the target speed parameters, and the speed difference of the clutch is determined in combination with the second speed ratio and the third speed ratio to determine whether the clutch has a slip failure.

[0048] Further, obtaining the clutch slip fault determination result according to the magnitude relationship between the speed difference and a preset speed difference threshold value includes:

[0049] If the duration that the speed difference of the clutch exceeds the preset speed difference threshold satisfies a preset time condition, a determination result that a slip fault occurs in the clutch is generated.

[0050] In the above implementation process, it is determined whether the speed difference exceeds the preset threshold value for a period of time. If the duration meets the preset time condition, it is determined that the clutch has a slip fault. This is because a short-term speed difference fluctuation may be caused by normal driving conditions, while a continuous speed difference is more likely to indicate a slip fault in the clutch.

[0051] A second aspect of an embodiment of the present application provides a control device, the control device comprising:

[0052] processor;

[0053] a memory for storing processor-executable instructions;

[0054] Wherein, when the processor calls the executable instruction, any method described in the first aspect is implemented.

[0055] A third aspect of an embodiment of the present application provides a vehicle, wherein the vehicle uses the control device as described in the second aspect.

[0056] A fourth aspect of the embodiments of the present application provides a computer program product, wherein the computer program product includes a computer program, and when the computer program is executed by a processor, any method described in the first aspect is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0058] Figure 1 A schematic flow chart of a clutch slip fault judgment method provided in an embodiment of the present application;

[0059] Figure 2 A schematic diagram of a hydraulically controlled clutch structure provided in an embodiment of the present application;

[0060] Figure 3 A schematic flow chart of another clutch slip fault judgment method provided in an embodiment of the present application;

[0061] Figure 4 A schematic flow chart of another clutch slip fault judgment method provided in an embodiment of the present application;

[0062] Figure 5 A schematic diagram of the overall flow of a system provided in an embodiment of the present application;

[0063] Figure 6 A schematic diagram of the structure of a control device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0064] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application.

[0065] It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of this application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0066] As hybrid transmissions become mainstream, the diagnosis of clutch slippage has become particularly important. Especially when key input signals are invalid or communication is abnormal, how to continue to make correct diagnosis is a problem that needs to be solved urgently.

[0067] In view of any of the above problems, the present application provides a clutch slip fault judgment method, referring to Figure 1 , Figure 1 A schematic flow chart of a clutch slip fault diagnosis method provided in an embodiment of the present application.

[0068] In this embodiment, the method is applied to a control device in a hybrid vehicle; the hybrid vehicle includes a clutch, an engine, a drive motor, and a generator; the method includes:

[0069] Step S10: when the vehicle is driven by hybrid power, obtaining the speed signal communication status between the drive motor and the engine and the control device; the speed signal communication status includes a normal communication status and an abnormal communication status;

[0070] It should be noted that the control device may be any controller in a hybrid vehicle. This example and the following embodiments are described by taking the control device as an ECU (electronic control unit) as an example.

[0071] Engine: This can be an internal combustion engine, responsible for generating power and connected to the transmission system through a clutch.

[0072] Drive motor: It can assist the engine in providing power, or it can drive the vehicle alone. In a series hybrid system, the drive motor drives the wheels directly or indirectly.

[0073] Generator: In a hybrid system, the generator is usually driven by the engine and is used to generate electricity for the drive motor or to charge the battery.

[0074] Clutch: The clutch is located between the engine and the transmission system and is used to control the transfer of power. In a series hybrid system, the clutch may be located between the engine and the generator, or between the drive motor and the wheels.

[0075] For example, in a series hybrid system, the connection between the clutch, the engine, the drive motor, and the generator is as follows: the engine directly drives the generator, and the generator drives the wheels through the drive motor. The clutch is between the engine and the generator and is used to control the transmission of the engine power.

[0076] It should be understood that during driving, the vehicle control system will automatically select the most appropriate power source or power combination according to different driving conditions (such as low-speed driving, acceleration, high-speed cruising, etc.). When a vehicle is driven by hybrid power, it means that when the VCU (vehicle control unit) requests the vehicle to enter parallel operation, the vehicle is powered by a combination of the engine and the drive motor, that is, the vehicle enters parallel operation.

[0077] Exemplarily, the abnormality in the speed signal communication between the drive motor and the control device may be manifested as: the CheckSum or LiveCounter corresponding to the drive motor speed message is incorrect, or the drive motor speed signal is judged to be invalid.

[0078] The abnormality of the speed signal communication between the engine and the control device can be manifested as: the CheckSum or LiveCounter corresponding to the engine speed message is incorrect, or the speed signal is judged to be invalid.

[0079] The normal communication status of the speed signal between the drive motor and the engine and the control device usually includes the following aspects:

[0080] Smooth signal transmission: There is no interruption in the transmission of speed signals between the drive motor and the engine and the control device, and data can be smoothly transmitted from the sensor to the control device.

[0081] Data integrity: The received speed signal data is intact, with no missing or damaged parts.

[0082] Data accuracy: The received speed signal data accurately reflects the actual speed of the engine and drive motor.

[0083] The communication protocol complies with the standard: the communication follows the prescribed communication protocol, such as the CAN (Controller Area Network) bus protocol or other industry standard protocols.

[0084] No communication interference: There is no electromagnetic interference or other forms of interference during the communication process, ensuring the quality of the signal.

[0085] Stable communication frequency: The signal update frequency is stable during the communication process and meets the preset requirements.

[0086] Step S20: based on the speed signal communication state, obtaining the target speed parameter of the vehicle, and based on the target speed parameter, determining the speed difference between the driving end and the driven end of the clutch; the target speed parameter includes any two of the generator speed, the drive motor speed, the wheel speed, and the engine speed;

[0087] It should be noted that, according to the selected target speed parameter, data is obtained from the corresponding sensor:

[0088] Generator speed: Get the generator speed data from the generator speed sensor;

[0089] Drive motor speed: obtain the drive motor speed data from the drive motor speed sensor;

[0090] Wheel speed: Get wheel speed data from the wheel speed sensor;

[0091] Engine speed: Get the engine speed data from the engine speed sensor.

[0092] The driving end speed of the clutch is determined according to one of the selected target speed parameters; the driven end speed of the clutch is determined according to another target speed parameter; and the difference between the driving end speed and the driven end speed is calculated, that is, the speed difference between the driving end and the driven end.

[0093] Specifically, if the communication between the drive motor and the control device is normal, and the communication between the engine and the control device is also normal, the generator speed and the drive motor speed can be selected as the target speed parameters;

[0094] If the communication between the drive motor and the control device is abnormal, but the communication between the engine and the control device is normal, the engine speed and the wheel speed may be selected as the target speed parameters;

[0095] If the communication between the drive motor and the control device is normal, but the communication between the engine and the control device is abnormal, the generator speed and the drive motor speed can be selected as the target speed parameter;

[0096] If the communication between the drive motor and the control device is abnormal, and the communication between the engine and the control device is also abnormal, the generator speed and the wheel speed may be selected as the target speed parameters.

[0097] Step S30: obtaining a slip fault determination result of the clutch according to a magnitude relationship between the speed difference and a preset speed difference threshold.

[0098] It should be noted that the preset speed difference threshold is a pre-set value used to determine whether the speed difference exceeds the normal range, which is helpful to distinguish between normal working state and fault state. The preset speed difference threshold is usually determined based on the design and performance requirements of the vehicle and experimental data. This embodiment does not limit the value and number of the preset speed difference threshold, and the preset speed difference threshold may include multiple ones.

[0099] For example, when the communication of the driving motor speed signal is normal, the clutch driven end speed is converted to the driving motor speed. At this time, the preset speed difference threshold can be set to 10 rpm.

[0100] When the communication of the drive motor speed signal is abnormal, such as when the CheckSum or LiveCounter corresponding to the drive motor speed message is incorrect, or when the drive motor speed signal is judged to be invalid, the clutch driven end speed is converted by the wheel speed. At this time, the preset speed difference threshold can be set to 100rpm.

[0101] When the communication of the engine speed signal is normal, the clutch active end speed is the engine speed.

[0102] When the communication of the engine speed signal is abnormal, such as when the CheckSum or LiveCounter corresponding to the engine speed message is incorrect, or when the speed signal is judged to be invalid, the active end speed of the clutch is converted to the generator speed.

[0103] The speed difference between the active end and the driven end of the clutch is calculated, and the speed difference is compared with the corresponding preset speed difference threshold. If the speed difference exceeds the preset speed difference threshold, it is determined that a slip fault has occurred in the clutch.

[0104] It should be noted that the conversion can be performed through the speed ratio (i.e. transmission ratio).

[0105] In this embodiment, during the driving process of the hybrid drive vehicle, the speed signal communication state between the drive motor and the engine and the control device is monitored, wherein the communication state is divided into a normal communication state and an abnormal communication state. According to the speed signal communication state, any two of the generator speed, the drive motor speed, the wheel speed, and the engine speed are selected as target speed parameters. Based on the target speed parameter, the speed difference between the active end and the driven end of the clutch is calculated. According to the size relationship between the speed difference and the preset speed difference threshold, it is determined whether the clutch has a slip fault. According to the communication state, a suitable target speed parameter is selected so that effective fault diagnosis can be performed under different communication states. Specifically, even in the case of abnormal communication between the drive motor or the engine and the control device, the speed difference of the clutch can be determined by selecting other available speed parameters, so as to continue fault diagnosis, which improves the adaptability and robustness of the system and maintains accurate fault judgment capabilities even under adverse conditions.

[0106] Based on any of the above embodiments, the hybrid vehicle further includes a hydraulic control system; and before acquiring the speed signal communication status between the drive motor and the engine and the control device, further includes:

[0107] Determine that the clutch meets the target condition; the target condition includes: any one or more of: the clutch is in a locked state, the clutch has no self-learning action, and the hydraulic control system has no leakage fault.

[0108] It should be understood that in the locked state: when the clutch is fully locked, there should theoretically be no speed difference. In this case, if a speed difference is detected between the active end and the driven end of the clutch (i.e., the engine flywheel and the clutch plate and pressure plate), this strongly indicates that there may be slippage inside the clutch. The locked state ensures the consistency and reliability of the test conditions.

[0109] No self-learning action: Modern vehicle control systems often perform self-learning or adaptive adjustments to optimize performance. If the clutch is self-learning or adjusting when slip fault detection is performed, this may interfere with normal speed difference measurement and lead to misjudgment. Ensuring no self-learning action can eliminate this interference and obtain more accurate measurement results.

[0110] No leakage fault: Leakage in the hydraulic system will directly affect the pressure applied to the clutch, thereby affecting the clutch engagement state. If there is a leak in the hydraulic system, the clutch may not reach the proper locking state, even when it should be locked in theory. Therefore, before detecting a slip fault, confirming that the system has no leakage can ensure the accuracy of the detection.

[0111] Optionally, after the clutch simultaneously satisfies the conditions of being in a locked state, having no self-learning action, and having no leakage fault in the hydraulic control system, the speed signal communication status between the drive motor and the engine and the control device is obtained.

[0112] It should be noted that the hydraulic control system consists of a BLDC motor, an oil pump and a hydraulic control valve. The electro-hydraulic actuator system controls the separation and engagement of the clutch, thereby ensuring the torque transmission of the clutch, thereby realizing the series-parallel connection of the hybrid system. When the VCU (vehicle control unit) requests the vehicle to enter parallel connection, the oil pump works to establish system pressure, and the hydraulic system pushes the clutch to engage. Figure 2 As shown, Figure 2 A schematic diagram of a hydraulically controlled clutch structure provided in an embodiment of the present application.

[0113] In the figure, 1 is a pressure relief valve, 2 is a clutch oil circuit, 3 is an electronic oil pump, 4 is an oil pool, 5 is an oil filter, and 6 is a pressure sensor. The system structure shown in the figure requires high pressure control accuracy, so it is equipped with a pressure sensor.

[0114] In this embodiment, before obtaining the speed signal communication status between the drive motor and the engine and the control device, it is first ensured that the clutch meets the target conditions. The target conditions include any one or more of the clutch being in a locked state, the clutch having no self-learning action, and the hydraulic control system having no leakage fault. In this way, the accuracy of the clutch slip fault detection can be further ensured.

[0115] Based on any of the above embodiments, acquiring a target speed parameter of the vehicle based on the speed signal communication state, and determining a speed difference between an active end and a driven end of the clutch based on the target speed parameter, comprises:

[0116] Based on the speed signal communication state, acquiring the target speed parameter and the target speed ratio;

[0117] It should be noted that the transmission ratio between the target speed parameters (i.e., the target speed ratio) is determined according to the specific configuration of the vehicle. Usually, the transmission ratio data between the various transmission components are provided in the design documents or user manual of the vehicle. This embodiment does not limit the method for determining the target speed ratio, and the target speed ratio can be set in advance and stored in the vehicle memory.

[0118] Based on the target speed parameter and the target speed ratio, a speed difference between the driving end and the driven end of the clutch is determined.

[0119] In the specific implementation, according to the communication state of the speed signal, any two of the generator speed, the drive motor speed, the wheel speed, and the engine speed are selected as the target speed parameters. Subsequently, the specific data of the target speed parameter collected by the corresponding sensor is obtained, and then the transmission ratio (i.e., the target speed ratio) of the target speed parameter is determined according to the specific configuration of the vehicle. The speeds of the active end and the driven end of the clutch are determined according to the selected target speed parameter and the corresponding speed ratio. The difference between the active end speed and the driven end speed is calculated, which is the speed difference between the active end and the driven end.

[0120] In this embodiment, a suitable target speed parameter is selected according to the communication state, so that effective clutch slip fault diagnosis can be performed under different communication states.

[0121] On the basis of any of the above embodiments, the first speed signal communication state between the drive motor and the control device, and the second speed signal communication state between the engine and the control device are both in normal communication state;

[0122] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0123] Acquiring the engine speed and the drive motor speed as the target speed parameter;

[0124] Specifically, when the speed signal communication state between the drive motor and the control device is in a normal communication state, and the speed signal communication state between the engine and the control device is in a normal communication state, the engine speed and the drive motor speed are used as target speed parameters.

[0125] Obtaining a first speed ratio, where the first speed ratio is a ratio between a speed of the driving motor and a speed of the driven end;

[0126] It should be noted that the first speed ratio is a transmission ratio between the rotational speed of the driving motor and the rotational speed of the driven end determined according to the specific configuration of the vehicle.

[0127] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0128] Determine the engine speed as the active end speed of the active end, and determine the driven end speed of the driven end according to the drive motor speed and the first speed ratio;

[0129] For example, if the engine speed is 2000RPM, the drive motor speed is 1000RPM, and the first speed ratio is 1:2 (i.e., the ratio between the drive motor speed and the driven end speed), then the driving end speed is 2000RPM, and the driven end speed is: drive motor speed × first speed ratio = 1000RPM × 2 = 2000RPM.

[0130] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0131] For example, if the driving end speed is 2000RPM, the driven end speed is: driving motor speed × first speed ratio = 1000RPM × 2 = 2000RPM, then the speed difference is the absolute value of the driving end speed minus the driven end speed, that is, the speed difference = |driving end speed - driven end speed| = |2000RPM-2000RPM| = 0RPM.

[0132] In this embodiment, if the speed signal between the drive motor and the control device and the speed signal between the engine and the control device are both in a normal communication state, the engine speed and the drive motor speed are obtained as target speed parameters, and the first speed ratio is obtained, the engine speed is determined as the active end speed, and then the driven end speed is determined according to the drive motor speed and the first speed ratio. Finally, the speed difference is determined according to the difference between the active end speed and the driven end speed. The engine speed and the drive motor speed are selected as the target speed parameters under normal communication conditions to ensure the validity of the data.

[0133] Based on any of the above embodiments, the first speed signal communication state between the drive motor and the control device is a normal communication state, and the second speed signal communication state between the engine and the control device is an abnormal communication state;

[0134] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0135] Acquiring the generator speed and the drive motor speed as the target speed parameters;

[0136] Obtaining a first speed ratio and a second speed ratio; the first speed ratio is the ratio between the rotation speed of the driving motor and the rotation speed of the driven end; the second speed ratio includes any one of the ratio between the rotation speed of the engine and the rotation speed of the generator, and the ratio between the rotation speed of the generator and the rotation speed of the active end of the clutch;

[0137] It should be noted that the connection mode between the engine, the generator, the clutch and the drive motor is determined according to the specific connection structure of the vehicle transmission system, so as to select a suitable second speed ratio. Specifically, if the generator is indirectly connected to the active end of the clutch (for example, through the engine), the second speed ratio is the ratio between the engine speed and the generator speed. If the generator is directly connected to the active end of the clutch, the second speed ratio is the ratio between the generator speed and the clutch active end speed.

[0138] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0139] Determining an active end speed of the active end according to the generator speed and the second speed ratio;

[0140] For example, if the ratio between the engine speed and the generator speed is selected as the second speed ratio, the second speed ratio=engine speed / generator speed, and the driving end speed=generator speed×second speed ratio.

[0141] The driven end speed of the driven end is determined according to the driving motor speed and the first speed ratio; specifically, the first speed ratio is obtained, and the driven end speed=driving motor speed / first speed ratio.

[0142] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0143] For example, if the engine speed = 2000RPM, the generator speed = 1000RPM, the drive motor speed = 1000RPM, the first speed ratio = 2:1, and the second speed ratio = 2:1, then the driving end speed = generator speed × second speed ratio = 1000RPM × 2 = 2000RPM, the driven end speed = drive motor speed / first speed ratio = 1000RPM / 2 = 500RPM, and the speed difference = 2000RPM-500RPM = 1500RPM.

[0144] In this embodiment, reliable speed data is selected for fault diagnosis between the speed of the driving motor in a normal communication state and the speed of the engine in an abnormal communication state, thereby improving the accuracy of fault diagnosis.

[0145] Based on any of the above embodiments, the first speed signal communication state between the drive motor and the control device is a communication abnormal state, and the second speed signal communication state between the engine and the control device is a communication normal state;

[0146] The obtaining of the target speed parameter and the target speed ratio based on the speed signal communication state includes: Figure 3 Steps S31-S32 shown:

[0147] Step S31: acquiring the engine speed and the wheel speed as the target speed parameter;

[0148] It is understandable that between the driving motor speed in the abnormal communication state and the engine speed in the normal communication state, the engine speed and the wheel speed are selected as the target speed parameters.

[0149] Step S32: obtaining a third speed ratio; the third speed ratio is a ratio between the rotation speed of the wheel end and the rotation speed of the driven end of the clutch;

[0150] It can be understood that the third speed ratio=wheel end speed / clutch driven end speed.

[0151] Determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes: Figure 4 Steps S41-S42 shown:

[0152] Step S41: determining the engine speed as the active end speed of the active end, and determining the driven end speed of the driven end according to the wheel speed and the third speed ratio;

[0153] Step S42: determining the difference between the driving end speed and the driven end speed as the speed difference.

[0154] For example, if the engine speed = 2000RPM, the wheel end speed = 1000RPM, and the third speed ratio = wheel end speed / driven end speed = 2:1, then the driving end speed = engine speed = 2000RPM, the driven end speed = wheel end speed / third speed ratio = 1000RPM / 2 = 500RPM, and the speed difference = |driving end speed - driven end speed| = |2000RPM-500RPM| = 1500RPM.

[0155] In this embodiment, between the driving motor speed in the abnormal communication state and the engine speed in the normal communication state, the engine speed and the wheel speed are selected for fault diagnosis, thereby improving the accuracy of fault diagnosis.

[0156] Based on any of the above embodiments, the first speed signal communication state between the drive motor and the control device is a communication abnormality state, and the second speed signal communication state between the engine and the control device is a communication abnormality state;

[0157] The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes:

[0158] Acquiring the generator speed and the wheel speed as the target speed parameters;

[0159] Obtaining a second speed ratio and a third speed ratio; the second speed ratio includes any one of a ratio between the engine speed and the generator speed, and a ratio between the generator speed and the clutch driving end speed; the third speed ratio is a ratio between the wheel end speed and the clutch driven end speed;

[0160] In a specific implementation, when the speed signal communication status between the drive motor and the control device is abnormal and the speed signal communication status between the engine and the control device is also abnormal, the generator speed and wheel speed collected by the sensor are used as target speed parameters, and the second speed ratio and the third speed ratio are obtained.

[0161] The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes:

[0162] Determining an active end speed of the active end according to the generator speed and the second speed ratio;

[0163] determining a driven end speed of the driven end according to the wheel speed and the third speed ratio;

[0164] The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

[0165] For example, if the generator speed = 1000RPM, the second speed ratio = engine speed / generator speed = 2:1, the wheel speed = 1000RPM, the third speed ratio = wheel end speed / driven end speed = 2:1, then the driving end speed = 1000RPM×2 = 2000RPM, the driven end speed = 1000RPM / 2 = 500RPM, and the speed difference = |2000RPM-500RPM| = 1500RPM.

[0166] In this embodiment, when the communication between the drive motor and the engine and the control device is abnormal, the generator speed and the wheel speed are selected as the target speed parameters to continue the fault diagnosis, thereby improving the adaptability and robustness of the system.

[0167] On the basis of any of the above embodiments, the step of obtaining the clutch slip fault determination result according to the magnitude relationship between the speed difference and a preset speed difference threshold value includes:

[0168] If the duration that the speed difference of the clutch exceeds the preset speed difference threshold satisfies a preset time condition, a determination result that a slip fault occurs in the clutch is generated.

[0169] It should be noted that in actual operation, the speed difference of the clutch may briefly exceed the threshold for various reasons, but it does not necessarily mean that there is a fault. By setting the preset time condition, these short-term fluctuations can be filtered out to avoid false alarms. Different clutch designs may have different tolerances, so the preset time conditions will also be different. The operating status of the vehicle under different working conditions will also affect the setting of the preset time conditions. Secondly, for some vehicles, there may be higher requirements for safety and performance, which may also affect the setting of the preset time conditions. This embodiment does not limit the preset time conditions. Generally, the preset time conditions can be set between a few seconds and tens of seconds. For example, if the speed difference exceeds the preset speed difference threshold for 2 seconds or more, it is considered that there is a slip fault in the clutch.

[0170] Optionally, when it is determined that the clutch has a slip fault, the oil pump reverses to control the clutch to disengage, and notifies the VCU (vehicle control unit) that the clutch cannot be engaged, and stores the clutch cannot be engaged fault code. A slip fault is not recoverable in a single driving cycle, that is, after a slip fault occurs, it is necessary to exit the parallel connection, that is, exit the mode of driving through hybrid power, and the vehicle will not enter the parallel connection again until the repair is completed.

[0171] like Figure 5 As shown, Figure 5 A schematic diagram of the overall process of a system provided for an embodiment of the present application. The figure shows the overall process of determining whether a slip fault occurs in the clutch. First, monitor whether the engine speed signal is faulty. If there is a fault, the EMG motor speed signal is used to determine the clutch active end speed. If there is no fault, the engine speed signal is directly used to determine the clutch active end speed. At the same time, monitor whether the drive motor signal is faulty. If there is a fault, the ABS wheel end signal is used to determine the clutch driven end speed. If there is no fault, the EMD motor speed signal is used to determine the clutch driven end speed. Calculate the difference between the clutch active end speed and the driven end speed. Check again whether the drive motor signal is faulty. If there is a fault, and the speed difference between the active end and the driven end is greater than 100rpm, and the duration exceeds the preset time, it is directly judged as a clutch slip fault; if there is a fault, but the speed difference between the active end and the driven end is less than or equal to 100rpm, then recheck whether the drive motor signal is faulty. If there is no motor signal fault and the speed difference is greater than 10rpm, and the duration exceeds the preset time, it is directly judged as a clutch slip fault; if there is no motor signal fault but the speed difference is less than or equal to 10rpm, recheck whether the drive motor signal is faulty. In addition, other conditions (such as pressure, speed difference duration, etc.) can be combined to comprehensively judge whether a slip fault occurs.

[0172] In this embodiment, by setting reasonable preset time conditions, the abnormal working state of the clutch can be effectively identified, reducing false alarms and missed alarms.

[0173] Based on the method described in any of the above embodiments, the present application also provides Figure 6 A schematic diagram of the structure of a control device is shown in FIG. Figure 6 At the hardware level, the control device includes a processor, an internal bus, a network interface, a memory, and a non-volatile memory, and may also include hardware required for other services. The processor reads the corresponding computer program from the non-volatile memory into the memory and then runs it to implement the method described in any of the above embodiments.

[0174] Based on the method described in any of the above embodiments, the present application also provides a vehicle, which uses the control device described in any of the above embodiments.

[0175] Based on the method described in any of the above embodiments, the present application also provides a computer program product, which includes one or more computer programs or instructions. The computer program or instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. When the computer program is executed by a processor, the method described in any of the above embodiments is implemented.

[0176] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram and / or flowchart, and the combination of boxes in the block diagram and / or flowchart can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0177] In addition, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist separately, or two or more modules may be integrated to form an independent part.

[0178] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium, including several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0179] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of 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 scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0180] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0181] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

Claims

1. A clutch slip fault judgment method, characterized in that: The method is applied to a control device in a hybrid drive vehicle; The hybrid vehicle includes a clutch, an engine, a drive motor, and a generator; the method includes: During the driving of the vehicle by hybrid power, the speed signal communication status between the drive motor and the engine and the control device is obtained; the speed signal communication status includes a normal communication status and an abnormal communication status; Based on the speed signal communication state, a target speed parameter of the vehicle is obtained, and based on the target speed parameter, a speed difference between the driving end and the driven end of the clutch is determined; the target speed parameter includes any two of the generator speed, the drive motor speed, the wheel speed, and the engine speed; According to the magnitude relationship between the rotation speed difference and a preset rotation speed difference threshold, a slip fault determination result of the clutch is obtained.

2. The method according to claim 1, characterized in that The hybrid vehicle further includes a hydraulic control system; and before acquiring the speed signal communication status between the drive motor and the engine and the control device, further includes: Determine that the clutch meets the target condition; the target condition includes: any one or more of: the clutch is in a locked state, the clutch has no self-learning action, and the hydraulic control system has no leakage fault.

3. The method according to claim 1, characterized in that The step of acquiring a target speed parameter of the vehicle based on the speed signal communication state, and determining a speed difference between an active end and a driven end of the clutch based on the target speed parameter, comprises: Based on the speed signal communication state, acquiring the target speed parameter and the target speed ratio; Based on the target speed parameter and the target speed ratio, a speed difference between the driving end and the driven end of the clutch is determined.

4. The method according to claim 3, characterized in that The first speed signal communication state between the drive motor and the control device, and the second speed signal communication state between the engine and the control device are both in normal communication state; The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes: Acquiring the engine speed and the drive motor speed as the target speed parameter; Obtaining a first speed ratio, where the first speed ratio is a ratio between a speed of the driving motor and a speed of the driven end; The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes: Determine the engine speed as the active end speed of the active end, and determine the driven end speed of the driven end according to the drive motor speed and the first speed ratio; The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

5. The method according to claim 3, characterized in that The first speed signal communication state between the drive motor and the control device is a normal communication state, and the second speed signal communication state between the engine and the control device is an abnormal communication state; The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes: Acquiring the generator speed and the drive motor speed as the target speed parameters; Obtaining a first speed ratio and a second speed ratio; the first speed ratio is the ratio between the rotation speed of the driving motor and the rotation speed of the driven end; the second speed ratio includes any one of the ratio between the rotation speed of the engine and the rotation speed of the generator, and the ratio between the rotation speed of the generator and the rotation speed of the active end of the clutch; The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes: Determining an active end speed of the active end according to the generator speed and the second speed ratio; Determining a driven end speed of the driven end according to the driving motor speed and the first speed ratio; The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

6. The method according to claim 3, characterized in that The first speed signal communication state between the drive motor and the control device is a communication abnormal state, and the second speed signal communication state between the engine and the control device is a communication normal state; The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes: Acquiring the engine speed and the wheel speed as the target speed parameter; Obtaining a third speed ratio; the third speed ratio is a ratio between the rotation speed of the wheel end and the rotation speed of the driven end of the clutch; The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes: Determine the engine speed as the active end speed of the active end, and determine the driven end speed of the driven end according to the wheel speed and the third speed ratio; The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

7. The method according to claim 3, characterized in that The first speed signal communication state between the drive motor and the control device is a communication abnormal state, and the second speed signal communication state between the engine and the control device is a communication abnormal state; The acquiring the target speed parameter and the target speed ratio based on the speed signal communication state includes: Acquiring the generator speed and the wheel speed as the target speed parameters; Obtaining a second speed ratio and a third speed ratio; the second speed ratio includes any one of a ratio between the engine speed and the generator speed, and a ratio between the generator speed and the clutch driving end speed; the third speed ratio is a ratio between the wheel end speed and the clutch driven end speed; The step of determining the speed difference between the driving end and the driven end of the clutch based on the target speed parameter and the target speed ratio includes: Determining an active end speed of the active end according to the generator speed and the second speed ratio; determining a driven end speed of the driven end according to the wheel speed and the third speed ratio; The difference between the driving end rotation speed and the driven end rotation speed is determined as the rotation speed difference.

8. The method according to claim 1, characterized in that The step of obtaining the clutch slip fault determination result according to the magnitude relationship between the speed difference and a preset speed difference threshold comprises: If the duration that the speed difference of the clutch exceeds the preset speed difference threshold satisfies a preset time condition, a determination result that a slip fault occurs in the clutch is generated.

9. A control device, characterized in that: The control device comprises: processor; a memory for storing processor-executable instructions; Wherein, when the processor calls the executable instruction, the method described in any one of claims 1-8 is implemented.

10. A vehicle, characterized in that: The vehicle uses the control device according to claim 9.

11. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the method according to any one of claims 1 to 8 is implemented.

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