Torque learning method and hybrid module

Abstract

The present invention relates to a torque learning method and a hybrid power module. A torque learning method for a hybrid vehicle is disclosed. The hybrid vehicle includes an engine for generating engine torque, an electric motor for generating motor torque, a separation clutch, a transmission and a clutch device. The separation clutch is arranged between the engine and the electric motor to selectively connect or disconnect the transmission of the engine torque of the engine. The clutch device is arranged between the electric motor and the transmission to selectively connect or disconnect the transmission of the motor torque of the electric motor and / or the engine torque of the engine to the transmission. The torque learning method includes: when a torque learning condition is met, controlling the clutch torque of the separation clutch so that the absolute value of the difference between the rotation speed of the engine and the rotation speed of the electric motor reaches a predetermined value, and storing and associating the motor torque of the electric motor with the clutch torque of the separation clutch.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid vehicles, and more particularly to a torque learning method and a hybrid vehicle module for hybrid vehicles. Background Art

[0002] A hybrid vehicle can combine the torque generated by the engine and the torque generated by the electric motor and transmit it to the clutch and transmission, and then to the drive shaft of the wheels. A P2 hybrid module is a hybrid module installed between the engine and the transmission. A P2 hybrid module generally includes a connecting device, a disconnect clutch, an electric motor, and a dual clutch device. The connecting device is used to mechanically connect the engine. The disconnect clutch can transfer the engine torque to the hybrid module and can disconnect the hybrid module from the engine. The dual clutch device can transfer torque from the electric motor and / or from the disconnect clutch to the transmission.

[0003] During the driving process of a hybrid vehicle, it is very important to learn and determine the torque actually transmitted by the clutch. In the prior art, the torque actually transmitted by the disconnect clutch is usually learned based on the engine torque. For example, when both the disconnect clutch and the dual clutch device are engaged, the clutch torque of the disconnect clutch is gradually reduced from the fully engaged state of the disconnect clutch. When the disconnect clutch produces micro-slip, the control unit considers that the current torque of the engine is roughly equivalent to the output torque of the disconnect clutch. However, the engine torque is inaccurate, and the error of the engine torque becomes larger and larger over time. In this case, an incorrect value may be obtained when learning the torque actually transmitted by the clutch. If the learned torque value is less than the actual value, the torque is not enough to actuate the disconnect clutch, which may cause the engine to fail to start. If the learned torque value is greater than the actual value, the torque is too high to actuate the disconnect clutch, and the motor compensates for the excess torque, which may cause excessive acceleration.

[0004] To this end, an accurate torque learning method for hybrid vehicles is needed. Summary of the invention

[0005] One object of the present invention is to provide an accurate torque learning method and a hybrid power module for a hybrid vehicle. Another object of the present invention is to provide a decoupling clutch torque learning method and a hybrid power module based on motor torque. Another object of the present invention is to provide a torque learning method and a hybrid power module that facilitate excellent driving performance.

[0006] One aspect of the present invention provides a torque learning method for a hybrid vehicle, the hybrid vehicle comprising an engine for generating engine torque, an electric motor for generating motor torque, a separating clutch, a transmission and a clutch device, the separating clutch being arranged between the engine and the electric motor to selectively connect or disconnect the transmission of the engine torque of the engine, the clutch device being arranged between the electric motor and the transmission to selectively connect or disconnect the transmission of the motor torque of the electric motor and / or the engine torque of the engine to the transmission, the torque learning method comprising: when the torque learning condition is met, controlling the clutch torque of the separating clutch so that the absolute value of the difference between the rotational speed of the engine and the rotational speed of the electric motor reaches a predetermined value, storing and associating the motor torque of the electric motor with the clutch torque of the separating clutch.

[0007] According to an embodiment of the present invention, the torque learning condition includes: the clutch device is disconnected, the engine torque of the engine is positive torque, and the motor torque of the motor is negative torque.

[0008] According to an embodiment of the present invention, the torque learning method further comprises: when the hybrid vehicle is running, determining the clutch torque currently required by the separation clutch according to the relationship between the motor torque and the clutch torque.

[0009] According to an embodiment of the present invention, the predetermined value is between 20 rpm and 80 rpm.

[0010] According to an embodiment of the present invention, the predetermined value is 50 rpm.

[0011] According to an embodiment of the present invention, controlling the clutch torque of the separation clutch so that the absolute value of the difference between the engine speed and the motor speed reaches a predetermined value includes: gradually reducing the clutch torque from the closed state of the separation clutch so that the difference between the engine speed and the motor speed reaches a predetermined value.

[0012] According to an embodiment of the present invention, when the torque learning condition is met, when the motor has different motor torques, the clutch torque of the separation clutch is controlled separately so that the absolute value of the difference between the engine speed and the motor speed reaches a predetermined value, and the motor torque of the motor and the clutch torque of the separation clutch are stored and associated.

[0013] According to an embodiment of the present invention, the clutch torque is controlled by hydraulic, pneumatic or electric means.

[0014] Another aspect of the present invention provides a hybrid power module, comprising: a separation clutch for selectively receiving engine torque from an engine; an electric motor for generating motor torque; a transmission; a clutch device arranged between the electric motor and the transmission for adjusting the input torque of the transmission; and a control device for executing a torque learning method according to an embodiment of the present invention.

[0015] According to an embodiment of the present invention, the torque learning method learns the clutch torque of the separation clutch based on the motor torque. Since the accuracy of the motor torque is much higher than the engine torque, a more accurate clutch torque can be learned. As a result, problems such as engine start failure or over-acceleration caused by inaccurate learned torque values ​​can be avoided. At the same time, excellent driving performance can be provided. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of a hybrid vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] Hereinafter, embodiments of the present invention are described with reference to the accompanying drawings. The following detailed description and the accompanying drawings are used to exemplarily illustrate the principles of the present invention, and the present invention is not limited to the preferred embodiments described. The scope of the present invention is defined by the claims. The present invention is now described in detail with reference to exemplary embodiments, and some embodiments are illustrated in the accompanying drawings. The following description is made with reference to the accompanying drawings, and unless otherwise indicated, the same reference numerals in different drawings represent the same or similar elements. The schemes described in the following exemplary embodiments do not represent all schemes of the present invention. On the contrary, these schemes are merely examples of systems and methods of various aspects of the present invention involved in the appended claims.

[0018] The present invention provides a torque learning method for a hybrid vehicle. Figure 1 Schematic diagram of a hybrid vehicle according to an embodiment of the present invention. Figure 1 As shown, the hybrid vehicle includes an engine 10 for generating engine torque, a motor 20 for generating motor torque, a separation clutch 30, a clutch device 40, a transmission 50 and a control device 60. According to an embodiment of the present invention, a hybrid module may include the motor 20, the separation clutch 30 and the clutch device 40.

[0019] The separation clutch 30 is disposed between the engine 10 and the motor 20. The separation clutch 30 can selectively connect or disconnect the transmission of the engine torque of the engine 10. When the separation clutch 30 is in the disconnected state, the engine torque of the engine 10 cannot be transmitted to the clutch device 40 and the transmission 50. Figure 1 As shown, when the separation clutch 30 is in an engaged state, the engine torque of the engine 10 can be transmitted to the clutch device 40 and the transmission 50. The separation clutch 30 may include a clutch actuator for controlling the clutch torque applied to the separation clutch. In an exemplary embodiment, the separation clutch 30 can be engaged or disengaged by the action of a hydraulic actuation force. In other embodiments, the separation clutch 30 can also control the clutch torque by pneumatic, electric, etc.

[0020] The clutch device 40 is arranged between the motor 20 and the transmission 50. The clutch device 40 can adjust the input torque of the transmission 50. Specifically, the clutch device 40 can selectively connect or disconnect the transmission of the engine torque of the engine 10 and / or the motor torque of the motor 20 to the transmission 50. According to certain embodiments of the present invention, the transmission 50 can be an automatic transmission. In an exemplary embodiment, the clutch device 40 can be a dual clutch device, and the transmission 50 can be a dual clutch transmission. In this case, the clutch device 40 may include two clutches, which are respectively torsionally connected to the inner input shaft and the outer input shaft of the transmission 50. The clutch device 40 may include a clutch actuator for controlling the clutch torque applied to the clutch device 40. In an exemplary embodiment, the clutch device 40 can be engaged or disconnected by the action of a hydraulic actuation force. In other embodiments, the clutch device 40 can also control the clutch torque by pneumatic, electric, etc.

[0021] The control device 60 is used in the hybrid vehicle to control the operation of various components and execute the method according to the embodiment of the present invention. The control device 60 can communicate with the engine 10, the motor 20, the separation clutch 30, the clutch device 40 and the transmission 50, and thus transmit data and control commands, etc.

[0022] The control device 60 may include various devices with processing functions, including but not limited to general-purpose processors, special-purpose processors, microprocessors, microcontrollers, graphics processors (GPUs), digital signal processors (DSPs), application-specific integrated circuits (ASICs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), etc. The control device 60 may include computer-executable instructions that are executed to perform the actions described in the present application. The control device 60 may include one or more memories. The memory may be used to store data, instructions, software, codes, etc. The memory may include semiconductor memories, such as random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, etc. The memory may also include, for example, any memory using paper media, magnetic media, and / or optical media, such as paper tape, hard disk, magnetic tape, floppy disk, magneto-optical disk (MO), CD, DVD, Blue-ray, etc.

[0023] The torque learning method according to an embodiment of the present invention will be described below. The torque learning method can be applied to Figure 1 A hybrid vehicle is shown in FIG.

[0024] According to an embodiment of the present invention, in order to perform torque learning, the control device 60 first determines whether the torque learning conditions are met. In an exemplary embodiment, the torque learning conditions include: the clutch device 40 is disconnected, the engine torque of the engine 10 is positive torque, and the motor torque of the motor 20 is negative torque. In this article, positive torque means that the direction of the force generated by the torque will cause the transmission shaft to rotate in the direction of the vehicle's forward movement, and negative torque means that the direction of the force generated by the torque will hinder the transmission shaft from rotating in the direction of the vehicle's forward movement. Figure 1 As shown, when the clutch device 40 is disconnected, the engine torque of the engine 10 is positive torque, and the motor torque of the motor 20 is negative torque, the control device 60 considers that torque learning of the separation clutch 30 can be performed.

[0025] According to an embodiment of the present invention, when performing torque learning, the control device 60 controls the clutch torque of the separation clutch 30 so that the absolute value of the difference between the rotation speed of the engine 10 and the rotation speed of the motor 20 reaches a predetermined value. In an exemplary embodiment, the predetermined value is between 20 RPM (revolutions per minute) and 80 RPM, for example, 50 RPM.

[0026] In some embodiments, starting from the fully engaged state of the separation clutch 30, the control device 60 gradually reduces the clutch torque of the separation clutch 30. In the fully engaged state of the separation clutch 30, the rotation speed of the engine 10 is the same as the rotation speed of the motor 20. As the clutch torque of the separation clutch 30 gradually decreases, the separation clutch 30 will produce micro-slip, and the rotation speed of the motor 20 will be slightly lower than the rotation speed of the engine 10. When the difference between the rotation speed of the engine 10 and the rotation speed of the motor 20 reaches, for example, 50 RPM, the control device 60 considers that the current motor torque of the motor 20 is substantially equivalent to the clutch torque of the separation clutch 30. Then, the control device 60 stores and associates the current motor torque and the corresponding clutch torque of the separation clutch 30.

[0027] During vehicle driving, the control device 60 can perform clutch torque learning for different motor torques when the torque learning condition is met. For different motor torques of the motor 20, the control device 60 can perform torque learning at predetermined torque intervals (for example, at intervals of 10 NM).

[0028] According to an embodiment of the present invention, the torque learning method further includes: when the hybrid vehicle is traveling, determining the clutch torque currently required by the separation clutch 30 according to the stored association between the motor torque and the clutch torque. In an exemplary embodiment, the control device 60 can retrieve the clutch torque corresponding to the motor torque. In some embodiments, for an intermediate torque value that has not been learned, the control device 60 can interpolate and calculate the corresponding clutch torque according to the torque value that has been learned, or use the pre-set clutch torque corresponding to the torque value.

[0029] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to the configuration and method of the above-described embodiments. On the contrary, the present invention is intended to cover various modifications and equivalent configurations. In addition, although the various elements and method steps of the disclosed invention are shown in various exemplary combinations and configurations, other combinations including more or less elements or methods also fall within the scope of the present invention.

Claims

1. A torque learning method for a hybrid vehicle, the hybrid vehicle comprising an engine for generating engine torque, an electric motor for generating motor torque, a separation clutch, a transmission and a clutch device, the separation clutch being arranged between the engine and the electric motor to selectively connect or disconnect the transmission of the engine torque of the engine, the clutch device being arranged between the electric motor and the transmission to selectively connect or disconnect the transmission of the motor torque of the electric motor and / or the engine torque of the engine to the transmission, The torque learning method comprises: When the torque learning condition is met, the clutch torque of the separation clutch is controlled so that the absolute value of the difference between the rotational speed of the engine and the rotational speed of the motor reaches a predetermined value, and the motor torque of the motor and the clutch torque of the separation clutch are stored and associated; wherein the torque learning condition includes: the clutch device is disconnected, the engine torque of the engine is positive torque and the motor torque of the motor is negative torque.

2. The torque learning method according to claim 1, further comprising: When the hybrid vehicle is running, the clutch torque currently required by the separation clutch is determined based on the correlation between the motor torque and the clutch torque.

3. The torque learning method according to claim 1, wherein: The predetermined value is between 20 rpm and 80 rpm.

4. The torque learning method according to claim 3, wherein: The predetermined value is 50 revolutions per minute.

5. The torque learning method according to any one of claims 1 to 4, wherein: Controlling the clutch torque of the separation clutch so that the absolute value of the difference between the speed of the engine and the speed of the motor reaches a predetermined value includes: gradually reducing the clutch torque from the closed state of the separation clutch so that the difference between the speed of the engine and the speed of the motor reaches the predetermined value.

6. The torque learning method according to any one of claims 1 to 4, wherein: When the torque learning condition is met, when the motor has different motor torques, the clutch torque of the separation clutch is controlled separately so that the absolute value of the difference between the speed of the engine and the speed of the motor reaches a predetermined value, and the motor torque of the motor and the clutch torque of the separation clutch are stored and associated.

7. The torque learning method according to any one of claims 1 to 4, wherein: The clutch torque is controlled hydraulically, pneumatically or electrically.

8. A hybrid power module, comprising: a disconnect clutch for selectively receiving engine torque from the engine; an electric motor for generating a motor torque; transmission; a clutch device, disposed between the motor and the transmission, for adjusting the input torque of the transmission; and A control device for executing the torque learning method according to any one of claims 1 to 7.

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