Self-checking strategy for position of gear shifting drum of hybrid transmission, electronic equipment and vehicle

Abstract

The invention relates to the technical field of vehicle hybrid gearbox control, in particular to a self-checking control strategy for the power-on position of a gear shifting drum of a multi-gear hybrid gearbox, electronic equipment and a vehicle. According to the position self-checking strategy for the gear shifting drum of the hybrid gearbox, after a vehicle is powered on, whether self-checking is allowed or not is recognized and judged, then the gear shifting drum is rotated towards the top dead center direction in a position closed-loop control mode, the effectiveness of the zero point of the stored position is calculated and judged, and therefore self-checking of the position of the powered-on gear shifting drum is achieved; the accuracy of the position zero point of the gear shifting drum at the beginning of each driving cycle can be ensured, and on the basis, the position calculation error of the gear shifting drum caused by the error of the stored position zero point can be effectively avoided, so that the gearbox can be prevented from being damaged, and the driving safety is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle hybrid transmission control, and in particular to a multi-speed hybrid transmission shift drum power-on position self-check control strategy, electronic equipment, and a vehicle. Background Art

[0002] The shift actuator of a multi-speed hybrid transmission usually adopts a drum-type shift actuator, that is, the HTCU (hybrid transmission control unit) issues a shift command and drives the BLDC (brushless DC) motor to rotate, which is decelerated and torque increased by the planetary gear mechanism, thereby driving the shift drum to rotate. The shift drum has two grooves, each of which is embedded with a shift fork. The rotational motion of the shift drum is converted into the linear reciprocating motion of the shift fork, driving the synchronizer to complete the shift. Each gear position corresponds to a fixed shift drum angle position. The intermediate transition process between two adjacent gear positions is the action of the synchronizer, during which the shift drum angle is in the non-gear position. Therefore, the accuracy of the shift drum position is very important.

[0003] However, before determining the shift drum angle position, a relative 0° point must be found as the shift drum position zero point. In the prior art, before the gearbox assembly product is off the production line, the host computer sends a command to the HTCU to first perform self-learning of the shift drum position, obtain the relative zero point of the shift drum position and store it in the HTCU. After the vehicle is powered on, based on this zero point, the HTCU controls the shift drum to move to the initial target gear position, that is, the initial shift drum position of the vehicle; Figure 1 As shown, there is a block in the circumferential position inside the shift drum, and the two sides of the block are the upper dead center and the lower dead center of the shift drum position respectively, wherein the upper dead center is used as the zero point of the shift drum position, and then the HTCU controls the shift drum to move to the target gear position based on this. However, in the prior art, when the stored HTCU position zero point is inconsistent with the actual zero point, it will cause the gear position of the gearbox to be disordered, thereby causing damage to the gearbox and even bringing driving safety risks. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a hybrid transmission shift drum position self-check strategy, which can ensure the accuracy of the shift drum position zero point at the beginning of each driving cycle, and use this as a benchmark to effectively avoid shift drum position calculation errors caused by stored position zero point errors, thereby preventing transmission damage and ensuring driving safety.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A hybrid transmission shift drum position self-check strategy, comprising:

[0007] S1, after the vehicle is powered on, the shift drum position self-check begins;

[0008] S2, determine whether the zero-point storage of the shift drum position is valid. If it is valid, continue to step S3. If it is invalid, re-perform position self-learning. After the self-learning is completed, the shift drum is controlled to return directly to the target gear position without performing position self-checking;

[0009] S3, determine the self-check permission condition. If the self-check permission condition is met, proceed to step S4. If not, the position self-check is no longer performed in the current driving cycle, and the shift drum returns directly to the target gear position.

[0010] S4, the shift motor drives the shift drum to rotate toward the top dead center through closed-loop control of the target shift drum position;

[0011] S5, when the shift motor and the shift drum are blocked, the control strategy of backing off after blocking is used to determine whether the current blocking point is the top dead center. If so, step S6 is continued. If not, it is considered that the stop block of the shift drum is damaged, and the vehicle is prohibited from starting;

[0012] S6, assigning the actual shift drum position during the current stall as the shift drum position zero point, and determining whether the shift drum position zero point is valid; if valid, the position zero point stored during the last power-off is still used as the position zero point for the current driving cycle for subsequent shift drum position calculation and control, while controlling the shift drum to return to the current target gear.

[0013] Furthermore, the method for determining whether the zero-point storage of the shift drum position is valid includes:

[0014] 1) The hybrid transmission control unit stores the position of the last power-off hibernation while calculating the verification value corresponding to the last storage position based on a preset verification algorithm and storing it;

[0015] 2) After the current power-on wake-up, the stored last position and check value are read, and based on the current stored position, the preset check algorithm is used to calculate the check value corresponding to the current storage position and store it;

[0016] 3) Compare the verification value stored last time with the verification value stored this time. If the error between the two is less than the preset error threshold, the zero point storage of the shift drum position is considered valid, otherwise the zero point storage of the shift drum position is considered invalid.

[0017] Furthermore, the self-check permission conditions include: first, the vehicle must be kept in P gear and stationary after power is turned on, and at the same time, the speeds of the engine, generator, and drive motor in the hybrid powertrain are all less than the corresponding preset speed thresholds, and the shift motor supply voltage is within a preset range.

[0018] Furthermore, the target shift drum position closed-loop control includes:

[0019] 1) Add the current actual shift drum angle to the preset value of the self-check shift drum angle (this preset value is a negative value) to obtain the target shift drum angle;

[0020] 2) performing PID control on the rotation angle of the shift motor based on the target shift drum angle;

[0021] 3) After converting the shift motor rotation angle into a shift drum angle, the current actual shift drum angle is replaced.

[0022] Furthermore, the stall identification method includes: if the shift drum position difference exceeds a preset angle threshold and the shift drum rotation angular velocity is lower than a preset angular velocity threshold, and the duration exceeds a preset time threshold, then it is considered that a stall has occurred.

[0023] Furthermore, the control strategy of falling back and trying again after stalling includes:

[0024] 1) When the gear shift drum is blocked, it moves back a certain angle in the opposite direction, and after the driving torque of the gear shift motor is increased by a preset value, step S4 is executed again to drive the gear shift drum to rotate toward the top dead center again;

[0025] 2) When it is identified that the number of stalled rotor back-off attempts exceeds the preset number, the current stalled rotor point is considered to be the top dead center.

[0026] Further, the shift drum position self-learning and the shift drum position self-checking are not triggered at the same time. When the shift drum position self-learning is not completed, the shift drum position self-checking is not allowed to be executed.

[0027] Compared with the prior art, the present invention has the following main advantages:

[0028] The present invention proposes a hybrid transmission shift drum position self-check strategy. After the vehicle is powered on, it identifies and determines whether self-check is allowed, then rotates the shift drum toward the top dead center in a position closed-loop control mode, calculates and determines the validity of the stored position zero point, so as to realize power-on shift drum position self-check. The accuracy of the shift drum position zero point at the beginning of each driving cycle can be ensured, and based on this, the shift drum position calculation error caused by the stored position zero point error can be effectively avoided, thereby preventing the transmission from being damaged and ensuring driving safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a plan view schematic diagram of the stop point and position of the shift drum in the background technology of the present invention;

[0030] Figure 2 It is a flow chart of the self-check control strategy for the power-on position of the shift drum of a multi-speed hybrid transmission in the first embodiment of the present invention;

[0031] Figure 3This is a logic block diagram of self-check permission condition judgment in Embodiment 2 of the present invention;

[0032] Figure 4 A logic block diagram of the self-checking and top dead center position control in the second embodiment of the present invention;

[0033] Figure 5 This is a logic block diagram of the stop point judgment and position validity judgment control according to the second embodiment of the present invention. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0035] It should be pointed out that, according to the needs of implementation, the various steps / components described in this application can be split into more steps / components, and two or more steps / components or partial operations of steps / components can be combined into new steps / components to achieve the purpose of the present invention.

[0036] In the present invention, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically limited.

[0037] Embodiment 1: This embodiment provides a hybrid transmission shift drum position self-check strategy, such as Figure 2 As shown, it mainly includes:

[0038] S1, after the vehicle is powered on, the shift drum position self-check begins;

[0039] S2, determine whether the zero-point storage of the shift drum position is valid. If it is valid, continue to step S3. If it is invalid, re-perform position self-learning. After the self-learning is completed, the shift drum is controlled to return directly to the target gear position without performing position self-checking;

[0040] S3, determine the self-check permission condition. If the self-check permission condition is met, proceed to step S4. If not, the position self-check is no longer performed in the current driving cycle, and the shift drum returns directly to the target gear position.

[0041] S4, the shift motor drives the shift drum to rotate toward the top dead center through closed-loop control of the target shift drum position;

[0042] S5, when the shift motor and the shift drum are blocked, the control strategy of backing off after blocking is used to determine whether the current blocking point is the top dead center. If so, step S6 is continued. If not, it is considered that the stop block of the shift drum is damaged, and the vehicle is prohibited from starting;

[0043] S6, assigning the actual shift drum position during the current stall as the shift drum position zero point, and determining whether the shift drum position zero point is valid; if valid, using the current power-off stored position zero point as the position zero point in the current driving cycle for subsequent shift drum position calculation and control, while controlling the shift drum to return to the current target gear.

[0044] Furthermore, the method for determining whether the zero-point storage of the shift drum position is valid includes:

[0045] 1) The hybrid transmission control unit stores the position of the last power-off hibernation while calculating the verification value corresponding to the last storage position based on a preset verification algorithm and storing it;

[0046] 2) After the current power-on wake-up, the stored last position and check value are read, and based on the current stored position, the preset check algorithm is used to calculate the check value corresponding to the current storage position and store it;

[0047] 3) Compare the verification value stored last time with the verification value stored this time. If the error between the two is less than the preset error threshold, the zero point storage of the shift drum position is considered valid, otherwise the zero point storage of the shift drum position is considered invalid.

[0048] Furthermore, the self-check permission conditions include: first, the vehicle must be kept in P gear and stationary after power is turned on, and at the same time, the speeds of the engine, generator, and drive motor in the hybrid powertrain are all less than the corresponding preset speed thresholds, and the shift motor supply voltage is within a preset range.

[0049] Furthermore, the target shift drum position closed-loop control includes:

[0050] 1) Add the current actual shift drum angle to the preset value of the self-check shift drum angle (this preset value is a negative value) to obtain the target shift drum angle;

[0051] 2) performing PID control on the rotation angle of the shift motor based on the target shift drum angle;

[0052] 3) After converting the shift motor rotation angle into a shift drum angle, the current actual shift drum angle is replaced.

[0053] Furthermore, the stall identification method includes: if the shift drum position difference exceeds a preset angle threshold and the shift drum rotation angular velocity is lower than a preset angular velocity threshold, and the duration exceeds a preset time threshold, then it is considered that a stall has occurred.

[0054] Furthermore, the control strategy of falling back and trying again after stalling includes:

[0055] 1) When the gear shift drum is blocked, it moves back a certain angle in the opposite direction, and after the driving torque of the gear shift motor is increased by a preset value, step S4 is executed again to drive the gear shift drum to rotate toward the top dead center again;

[0056] 2) When it is identified that the number of stalled rotor back-off attempts exceeds the preset number, the current stalled rotor point is considered to be the top dead center.

[0057] Further, the shift drum position self-learning and the shift drum position self-checking are not triggered at the same time. When the shift drum position self-learning is not completed, the shift drum position self-checking is not allowed to be executed.

[0058] Embodiment 2: This embodiment provides a hybrid transmission shift drum position self-check strategy, and the specific control strategy includes:

[0059] 1) After HTCU receives KL15 hard line wake-up, the HTCU bottom-level software feedback key status signal is On, the application layer identifies the key status from off to on rising edge triggering self-test, at the same time, the bottom-level software determines whether the shift drum position zero point storage itself is valid, and the application layer continues to the next self-test permission judgment after receiving the storage is valid. If the storage is invalid, the application layer will re-perform position self-learning. After the self-learning is completed, the HTCU controls the shift drum to return directly to the target gear position, and no longer performs position self-test. Among them, the bottom-level method for judging the validity of the position zero point storage is to calculate the corresponding verification value of the storage position based on the established verification algorithm when the HTCU last powered down and hibernated and stored the position. After the next power-on wake-up, the bottom-level reads the stored position and verification value, and uses the same verification algorithm to calculate the corresponding verification value based on the stored position again, and compares the recalculated verification value with the stored verification value. If the two are consistent, the position zero point storage is considered valid, otherwise the position is lost.

[0060] 2) After determining that the position storage is valid, perform self-check permission condition determination: Figure 3As shown, first of all, the vehicle must be kept in P gear and stationary after power is turned on. At the same time, the speed of each power source (engine, generator, drive motor) in the hybrid powertrain should theoretically be stationary, but the actual software is set to be lower than a certain threshold. This is mainly because when the shift drum rotates between the current gear position and the top dead center during the self-test execution, it will drive the shift fork-synchronizer to move, which may cause the power source to rotate slightly for a short time. If the power source speed condition is strictly set to 0, it may cause the self-test process to be triggered. After the power source conditions are met, in order to ensure that the shift motor can drive the shift drum normally, the corresponding shift motor power supply voltage is also in the normal range (9~16V). In addition, the shift drum position self-learning and self-test should not be triggered at the same time. The premise of self-test is that the position self-learning is completed or self-learning is not performed. If the self-test conditions are not allowed, the current driving cycle will no longer perform self-test and directly return to the target gear.

[0061] 3) After allowing self-test, HTCU controls the shift motor to drive the shift drum to rotate towards the top dead center. Figure 4 As shown, the control method is closed-loop control of the target shift drum position. The corresponding target shift drum angle is the current shift drum angle plus the self-check shift drum angle preset value (such as -5°). This preset value must be a negative value, so that the shift drum will rotate toward the top dead center at a certain angular velocity.

[0062] 4) According to the above control method, when the shift drum rotates to the top dead center, the HTCU will still output the duty cycle to drive the shift motor. At this time, the shift motor-shift drum will be blocked. The HTCU regards the shift drum position corresponding to this block as the zero point of the shift drum position. In addition, to ensure that the shift drum has actually reached the top dead center instead of being blocked before the top dead center due to mechanical stagnation, the software should avoid misidentifying this blocked position as the top dead center. Figure 5 As shown in the figure, a strategy of retreating and retrying after stalling is designed in the shift drum position rotation control, that is, when stalling, the shift drum retreats a certain angle in the opposite direction, and continues to move toward the top dead center using the control method mentioned in 3). At the same time, when trying again, the shift drum position control output increases by a certain coefficient (such as 1.5), that is, the shift motor drive torque increases by a certain coefficient. Finally, when it is identified that the number of stalling retreat attempts exceeds 2 times, the current stall point is considered to be the top dead center. Among them, the method for identifying stalling is: when the shift drum position difference exceeds 2° and the shift drum rotation angular velocity is less than 10° / s, and waits for 250ms, it is considered to be stalled. The principle is that the shift motor output duty cycle will continue to increase due to the position PID control, and the shift drum has almost no movement, which is a stall. If the top dead center is not found, it is very likely that the shift drum stop block is damaged, that is, the hybrid transmission hardware is damaged, and the vehicle will be prohibited from starting.

[0063] 5) After finding the top dead center, the actual shift drum position at the current stall is assigned as the shift drum position zero point. If this zero point is basically consistent with the position zero point stored before the last power-off, the stored shift drum position zero point is considered valid. In actual software, mechanical and control errors are taken into account, and the absolute value of the difference between the two is used to judge the validity of the position zero point, such as if the difference is less than 0.5°.

[0064] 6) After judging that the position is valid, the software will still use the position zero point stored at the last power-off as the position zero point in the current driving cycle for subsequent shift drum position calculation and control, and control the shift drum to the current target gear position. At this point, the entire power-on shift drum position self-check is completed.

[0065] Embodiment 3: Based on the same inventive concept, this embodiment also provides a vehicle electronic device, including a memory, a processor, and a program stored in the memory and executable on the processor, wherein when the processor executes the program, the power-on position self-check control strategy of the multi-speed hybrid transmission shift drum as described above is implemented.

[0066] Embodiment 4: Based on the same inventive concept, this embodiment further provides a hybrid vehicle, wherein the vehicle is provided with the vehicle electronic device as described above.

[0067] Furthermore, all parts involved in this application that are not described in detail are the same as the prior art or are implemented using the prior art.

[0068] In summary:

[0069] The present invention proposes a hybrid transmission shift drum position self-check strategy. After the vehicle is powered on, it identifies and determines whether self-check is allowed, then rotates the shift drum toward the top dead center in a position closed-loop control mode, calculates and determines the validity of the stored position zero point, so as to realize power-on shift drum position self-check. The accuracy of the shift drum position zero point at the beginning of each driving cycle can be ensured, and based on this, the shift drum position calculation error caused by the stored position zero point error can be effectively avoided, thereby preventing the transmission from being damaged and ensuring driving safety.

[0070] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0071] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0072] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0073] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0074] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A hybrid transmission shift drum position self-check strategy, characterized in that: include: After the vehicle is powered on, it starts to perform the shift drum position self-check and determines whether the shift drum position zero point storage is valid; If the zero-point storage of the shift drum position is valid and meets the self-check permission conditions, the shift motor drives the shift drum to rotate toward the top dead center through the closed-loop control of the target shift drum position; When the shift motor and the shift drum are blocked, the control strategy is used to determine whether the current blocking point is the top dead center by backing off after blocking; If the current stall point is the top dead center, the actual shift drum position at the current stall is assigned as the shift drum position zero point, and it is determined again whether the current shift drum position zero point is valid; If the current shift drum position zero point is valid, the current shift drum position zero point is used as the position zero point in the current driving cycle for subsequent shift drum position calculation and control, and the shift drum is controlled to return to the current target gear.

2. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: The method for determining whether the zero-point storage of the shift drum position is valid comprises: The hybrid transmission control unit stores the position when it was powered off and dormant last time, and at the same time calculates the verification value corresponding to the last stored position based on a preset verification algorithm and stores it; After the current power-on wake-up, the stored last position and check value are read, and based on the current stored position, the check value corresponding to the current stored position is calculated using the preset check algorithm and stored; The check value stored last time is compared with the check value stored this time. If the error between the two is less than the preset error threshold, the shift drum position zero point storage is considered valid, otherwise the shift drum position zero point storage is considered invalid.

3. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: The self-check permission conditions include: First, after the vehicle is powered on, it must be kept in P gear and stationary. At the same time, the speed of the engine, generator, and drive motor in the hybrid powertrain are all less than the corresponding preset speed threshold, and the shift motor supply voltage is within the preset range.

4. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: The target shift drum position closed-loop control comprises: The current actual shift drum angle is added to the preset value of the self-check shift drum angle to obtain the target shift drum angle; Performing PID control on the rotation angle of the shift motor based on the target shift drum angle; After the shift motor rotation angle is converted into a shift drum angle, the current actual shift drum angle is replaced.

5. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: The stall identification method includes: if the shift drum position difference exceeds a preset angle threshold and the shift drum rotation angular velocity is lower than a preset angular velocity threshold, and the duration exceeds a preset time threshold, then it is considered that a stall occurs.

6. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: The control strategy of falling back and trying again after stalling includes: When the gear shift drum is blocked, it moves back a certain angle in the opposite direction, and after the shift motor driving torque is increased by a preset value, the shift drum is driven to rotate toward the top dead center again; When it is identified that the number of stalled rotor back-off attempts exceeds the preset number, the current stalled rotor point is considered to be the top dead center.

7. A hybrid transmission shift drum position self-checking strategy according to claim 1, characterized in that: If it is determined that the current stall point is not the top dead center, it is considered that the shift drum stop block is damaged and the vehicle is prohibited from starting.

8. A vehicle electronic device, comprising a memory, a processor, and a program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, the power-on position self-check control strategy of the multi-speed hybrid transmission shift drum is implemented as described in any one of claims 1 to 7.

9. A non-transitory readable storage medium having a program stored thereon, characterized in that: When the program is executed by the vehicle electronic device, the power-on position self-check control strategy of the multi-speed hybrid transmission shift drum as claimed in any one of claims 1 to 7 is implemented.

10. A hybrid vehicle, characterized in that: The vehicle electronic device comprising the vehicle electronic device as claimed in claim 8.

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