Simulation method and device of hybrid power transmission system gear shifting process and computer readable storage medium

Abstract

The embodiment of the application provides a simulation method and device of a hybrid power transmission system gear shifting process and a computer readable storage medium. The method comprises: establishing a one-dimensional torsional vibration model of the hybrid power transmission system under full throttle conditions; establishing a gear shifting control strategy model in an acceleration process based on a gear shifting map of the hybrid power transmission system under full throttle conditions, wherein the gear shifting control strategy model stores a formulated gear shifting control strategy; performing joint simulation based on the one-dimensional torsional vibration model and the gear shifting control strategy model; and optimizing the gear shifting control strategy and / or the hybrid power transmission system based on a simulation result. Thus, the hybrid power transmission system can be evaluated in the early stage of product development through the simulation method, and problems in the later stage are avoided to reduce development costs and time costs.

Description

Technical Field

[0001] The present invention relates to the field of automotive technology, and in particular to a simulation method and apparatus for the shifting process of a hybrid powertrain system, as well as a computer-readable storage medium. Background Technology

[0002] When developing and validating multi-speed hybrid systems, the primary method is prototype testing to verify the effectiveness of the technical solutions. In the early stages of development, once the clutch torque capacity and dual-mass flywheel torque capacity are selected, insufficient torque during subsequent gear shifts necessitates either reducing engine torque or redeveloping the clutch or dual-mass flywheel (as the design space is already fixed), resulting in high development costs and long development cycles. Furthermore, troubleshooting clutch slippage and shaft breakage issues arising from system matching is extremely difficult. Summary of the Invention

[0003] The purpose of this invention is to provide a simulation method, apparatus, and computer-readable storage medium for the shifting process of a hybrid powertrain, which enables the evaluation of the hybrid powertrain in the early stages of product development, avoiding increased development costs and time due to problems later on.

[0004] One aspect of this invention provides a simulation method for the shifting process of a hybrid powertrain. The simulation method includes: establishing a one-dimensional torsional vibration model of the hybrid powertrain under full throttle conditions; establishing a shift control strategy model during acceleration based on the shift map of the hybrid powertrain under full throttle conditions, wherein the shift control strategy model stores a predetermined shift control strategy; performing joint simulation based on the one-dimensional torsional vibration model and the shift control strategy model; and optimizing the shift control strategy and / or the hybrid powertrain based on the simulation results.

[0005] Another aspect of this invention provides a simulation apparatus for the gear shifting process of a hybrid powertrain. The simulation apparatus includes one or more processors for implementing the simulation method for the gear shifting process of a hybrid powertrain as described above.

[0006] Another aspect of the present invention provides a computer-readable storage medium having a program stored thereon, which, when executed by a processor, implements a simulation method for the shifting process of a hybrid powertrain as described above.

[0007] The present invention provides a simulation method, apparatus, and computer-readable storage medium for the shifting process of a hybrid powertrain system, comprising one or more embodiments. Utilizing computer-aided tools, it combines shift control strategies and transmission system torque to evaluate the entire hybrid system. This allows for early-stage product development assessment using virtual simulation to evaluate issues such as excessive torque surges during shifting caused by unreasonable hybrid shifting strategies or inadequate transmission system torque capacity design. Furthermore, by evaluating the components of the hybrid powertrain system, it avoids increasing development costs and time associated with later-stage problems. Attached Figure Description

[0008] Figure 1 A flowchart illustrating a simulation method for the gear shifting process of a hybrid powertrain system according to an embodiment of the present invention;

[0009] Figure 2 The following are the specific steps of a simulation method for the gear shifting process of a hybrid powertrain system according to an embodiment of the present invention.

[0010] Figure 3 This is a simplified model of a hybrid powertrain system according to an embodiment of the present invention;

[0011] Figure 4 This is a schematic diagram illustrating the torque change during a gear shift.

[0012] Figure 5 This is a schematic diagram of the control logic of a shift control strategy according to an embodiment of the present invention;

[0013] Figure 6 This is a schematic diagram of the cylinder pressure curve at full load for a certain engine;

[0014] Figure 7 A schematic diagram showing the maximum operating torque of motors P1 / P3;

[0015] Figure 8 This is a shift map of a hybrid transmission.

[0016] Figure 9 This is a schematic diagram of the torsional vibration results under two WOT conditions;

[0017] Figure 10 A schematic diagram considering the torsional vibration results during gear shifting;

[0018] Figure 11 This is a schematic block diagram of a simulation device for the gear shifting process of a hybrid powertrain system according to an embodiment of the present invention. Detailed Implementation

[0019] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numerals in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatuses consistent with some aspects of the invention as detailed in the appended claims.

[0020] The terminology used in this invention embodiment is for the purpose of describing particular embodiments only and is not intended to limit the invention. Unless otherwise defined, the technical or scientific terms used in this invention embodiment should be understood in their ordinary sense by one of ordinary skill in the art to which this invention pertains. The terms "first," "second," and similar terms used in this specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, "a" or "one," and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. "A plurality" or "several" indicates two or more. Unless otherwise stated, "front," "rear," "lower," and / or "upper," and similar terms are for ease of description only and are not limited to a location or spatial orientation. The terms "comprising" or "including," and similar terms mean that the element or object preceding "comprising" covers the element or object listed following "comprising" or "including" and its equivalents, and do not exclude other elements or objects. The terms "connected," "linked," and similar terms are not limited to physical or mechanical connections and can include electrical connections, whether direct or indirect. The singular forms “a,” “the,” and “the” used in this specification and appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0021] This invention provides a simulation method for the gear shifting process of a hybrid powertrain. Figure 1 A flowchart illustrating a simulation method for the gear shifting process of a hybrid powertrain according to an embodiment of the present invention is provided. Figure 2 The specific steps of a simulation method for the gear shifting process of a hybrid powertrain system according to an embodiment of the present invention are disclosed. For example... Figure 1 and Figure 2 As shown, a simulation method for the shifting process of a hybrid powertrain system according to an embodiment of the present invention may include steps S1 to S4.

[0022] In step S1, a one-dimensional torsional vibration model of the hybrid powertrain under the whole open throttle (WOT) condition is established.

[0023] In some embodiments, the establishment of a one-dimensional torsional vibration model of the hybrid powertrain under full throttle conditions in step S1 may further include steps S11 to S13.

[0024] In step S11, parameters of the hybrid powertrain can be collected.

[0025] The parameters of a hybrid powertrain system may include, but are not limited to, those of the crankshaft system, dual-mass flywheel, clutch, P1 motor, P3 motor, gearbox, brakes, half-shafts, tires, and vehicle weight. Specifically, the crankshaft system includes the inertia and stiffness of the crankshaft, connecting rods, pistons, and balance shaft; the gearbox includes the stiffness and inertia of the shafts in each gear position; the clutch includes its corresponding torque limit capacity; the brakes include their corresponding torque limit capacity; and the dual-mass flywheel includes its spring stiffness curve and limiting angle.

[0026] The P1 motor mentioned in this specification refers to the motor located in front of the clutch at the engine output end; the P3 motor refers to the motor located between the transmission and the front axle wheels.

[0027] In step S12, a simplified approach to the hybrid powertrain under full throttle conditions can be determined.

[0028] In some embodiments, the hybrid powertrain can be modeled and simplified based on the axial torsional direction of the hybrid powertrain and the inertia of the motor under full throttle conditions.

[0029] Specifically, the crankshaft system is simplified into a torsional system model of inertia-damping-stiffness, the dual-mass flywheel is simplified into an inertia-arc spring-dynamic damping model, the clutch / brake is simplified into an inertia-friction-closing torque model, and the P1 / P3 motors are only considered in terms of their inertia-stiffness and input torque. Other shafts and gears inside the transmission are also simplified into inertia-damping-stiffness models. The engine, dual-mass flywheel, P1 motor, clutch, transmission, differential, half-shaft, tires and the whole vehicle are connected in series to form a complete hybrid power transmission system model. Figure 3 A simplified model of a hybrid powertrain system according to an embodiment of the present invention is disclosed. Figure 2 As shown, 1 represents the engine, 2 represents the dual-mass flywheel, 3 represents the P1 motor, 4 represents the C0 clutch, 5 represents the transmission, 6 represents the B1 brake, 7 represents the B2 brake, 8 represents the P2 motor, 9 represents the main reducer, and 10 represents the tires and the whole vehicle.

[0030] In step S13, a one-dimensional torsional vibration model of the hybrid powertrain under full throttle conditions can be built based on the parameters of the hybrid powertrain and according to a simplified approach.

[0031] In step S2, a shift control strategy model is established based on the shift map of the hybrid powertrain under full throttle conditions during acceleration. The shift control strategy model stores the defined shift control strategy.

[0032] In some embodiments, a Simulink shift control strategy model for the acceleration process can be built in the Simulink platform based on the shift map of the hybrid powertrain under full throttle conditions.

[0033] The following will combine Figure 4 The working principle of gear shifting in a hybrid powertrain system is explained in detail.

[0034] Actual shift control ensures the wheel-end torque T out Under the condition of constant torque, coordinate the engine torque T ice Clutch torque T C0 Brake torque T B1 T B2 and motor torque T P1 T P2 The method of understanding the relationship between these factors ultimately achieves the process of reducing the inertia speed of the transmission system. The gear shifting process is divided into four parts: the original gear operation, the torque phase, the inertia phase, and the new gear operation.

[0035] Taking a vehicle accelerating from 1st gear to 2nd gear as an example, when the vehicle reaches the shift point in the original gear (the speed for upshifting / downshifting is determined by the vehicle speed, throttle, and current gear in the shift map), it enters the torque phase: the engine reduces torque, the P1 motor reduces torque, the B1 brake disengages to reduce torque, and simultaneously the B2 brake closes for slip friction to increase torque. When the B1 brake is fully disengaged, it enters the inertia phase: the B2 brake remains closed, torque increases, the P1 and P2 motors operate, reducing the inertia of the transmission system in 1st gear to reach the new shift speed. At this moment, the B2 brake completes the gear shift, slip friction ends, the relative speed of the clutch is 0 rpm, the brake torque decreases, and the vehicle shifts to 2nd gear. Figure 4 A schematic diagram illustrating torque changes during gear shifting is presented.

[0036] The following will combine Figure 5 The control logic of a shift control strategy according to an embodiment of the present invention will be described in detail below.

[0037] Figure 5 A schematic diagram of the control logic for a shift control strategy according to an embodiment of the present invention is shown. Figure 5 As shown, in some embodiments, in step S21, it is determined whether a gear shift is in progress. If the determination result is no, the process proceeds to step S22. If the determination result is yes, the process proceeds to step S23. In step S22, if it is determined that a gear shift is not in progress, the process enters non-gear shift control.

[0038] In step S23, when the gear shifting process is underway, the shifting time is determined according to the shifting map, and the torque phase stage is entered to perform torque phase control.

[0039] During the torque phase, the clutch torque and B1 brake torque are calculated based on the engine torque, P1 motor torque, and P3 motor torque to determine the torque phase adjustment method for gear shifting.

[0040] In step S24, after the torque phase control is completed, the inertia phase stage is entered to perform inertia phase control.

[0041] During the inertia phase, the torque adjustment methods for motors P1, P3, and B2 are determined based on the shift time requirements.

[0042] In step S25, the gear is switched to a new gear after the inertia phase phase is completed.

[0043] In step S26, it is checked whether the engine (ICE) torque, P1 motor torque, P3 motor torque, C0 clutch torque, B1 brake torque, and B2 brake torque exceed their respective torque capacities.

[0044] In step S27, after confirming that the engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque, and B2 brake torque do not exceed their respective torque capacities, the engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque, and B2 brake torque are imported into the one-dimensional torsional vibration model in step S1.

[0045] Continue to refer to Figure 5 As shown, the shift control strategy further includes steps S28 and S29. In step S28, the wheel-end output torque is estimated. In step S29, the torque changes of the engine, P1 motor, P3 motor, clutch, B1 brake, and B2 brake can be obtained based on the wheel-end output torque.

[0046] In step S3, a joint simulation is performed based on the one-dimensional torsional vibration model and the shift control strategy model.

[0047] The load parameters of the hybrid powertrain are collected and input into a one-dimensional torsional vibration model. Load excitation is then applied to the one-dimensional torsional vibration model.

[0048] First, the cylinder pressure curves of the engine under full throttle conditions are collected as the input boundary conditions for full throttle operation. Figure 6 A schematic diagram of the full-load cylinder pressure curve of a certain engine is shown. Secondly, the maximum torque curves of motors P1 and P3 are collected to represent the limiting operating range of the motors. Figure 7 A schematic diagram showing the maximum operating torque of motors P1 / P3 is presented. Finally, the shift map of the hybrid powertrain under full throttle conditions is determined, showing the vehicle speed and corresponding engine speed corresponding to upshifts. Figure 8 The shift map of a certain hybrid transmission is revealed.

[0049] The engine speed, vehicle speed, engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque, and B2 brake torque are transmitted to the shift control strategy model. Simultaneously, the shift control strategy model outputs and feeds back the corresponding engine speed, engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque, and B2 brake torque to the one-dimensional torsional vibration model. Since the Simulink shift control strategy model only involves torque triggering and variation, and does not involve changes in the inertia-stiffness of the one-dimensional torsional vibration model, it does not affect the characteristics of the transmission system.

[0050] The hybrid power transmission system of this invention takes torsional vibration into account, checks the torsional vibration of the shaft system and the torque on each component, and also takes into account the torque switching caused by gear shifting, so as to comprehensively evaluate the actual torsional vibration under WOT conditions and the overload problem caused by torque transformation.

[0051] In step S4, the shift control strategy and / or hybrid powertrain are optimized based on the simulation results.

[0052] In some embodiments, optimizing the shift control strategy and / or hybrid powertrain based on simulation results in step S4 includes: evaluating the various components of the hybrid powertrain based on simulation results; and optimizing the components and / or shift control logic of the hybrid powertrain based on the evaluation results.

[0053] Simulation results can be used to verify whether the torque capacity of the engine, clutch, B1 brake, B2 brake, and dual-mass flywheel is excessive or insufficient. Therefore, the torque capacity of each component of the hybrid powertrain can be optimized based on simulation results.

[0054] Figure 9 A schematic diagram showing the torsional vibration results under two WOT conditions is presented. (For example...) Figure 9 As shown, affected by torsional vibration (torsional vibration speed 3500rpm), the limit angle of the dual-mass flywheel is 39°, the C0 clutch torque is 377Nm, and the B2 brake torque is 489Nm.

[0055] Figure 10 A schematic diagram showing the torsional vibration results considering gear shifting is presented. For example... Figure 10As shown, for the case of rapidly shifting from 1st gear to 2nd gear during acceleration (gear shift to 3500rpm), the maximum rotation angle of the dual-mass flywheel is 45.3°, the minimum torque requirement of the C0 clutch is 542Nm, and the minimum torque requirement of the B2 brake is 495Nm.

[0056] The simulation method for the shifting process of the hybrid powertrain system in this invention can be used in the state of a hybrid multi-gear transmission to avoid torsional vibration and torque shock in the transmission system caused by gear switching. At the same time, it can quickly match the entire hybrid system and verify whether the torque capacity of the selected engine, clutch / brake, and dual-mass flywheel is excessive or insufficient, while avoiding shaft breakage caused by torque shock.

[0057] The simulation method for the shifting process of a hybrid powertrain system in this invention utilizes computer-aided tools to combine shifting control strategies and transmission system torque to evaluate the entire hybrid system. In the early stages of product development, virtual simulation can be used to assess issues such as excessive torque surges during shifting caused by unreasonable hybrid shifting strategies or inadequate transmission system torque capacity design. Furthermore, by evaluating the components of the hybrid powertrain system, it is possible to avoid increasing development costs and time due to problems that arise later.

[0058] This invention also provides a simulation device 200 for the gear shifting process of a hybrid powertrain system. Figure 11 A schematic block diagram of a simulation device 200 for the gear shifting process of a hybrid powertrain system according to an embodiment of the present invention is shown. Figure 11 As shown, the simulation device 200 for the gear shifting process of a hybrid powertrain may include one or more processors 201 for implementing the simulation method for the gear shifting process of a hybrid powertrain as described in any of the above embodiments. In some embodiments, the simulation device 200 for the gear shifting process of a hybrid powertrain may include a computer-readable storage medium 202, which may store a program that can be called by the processor 201, and may include a non-volatile storage medium. In some embodiments, the simulation device 200 for the gear shifting process of a hybrid powertrain may include a memory 203 and an interface 204. In some embodiments, the simulation device 200 for the gear shifting process of a hybrid powertrain according to the present invention may also include other hardware depending on the actual application.

[0059] The simulation device 200 for the shifting process of a hybrid powertrain system according to this embodiment of the invention has similar beneficial technical effects to the simulation method for the shifting process of a hybrid powertrain system described above, and therefore will not be repeated here.

[0060] This invention also provides a computer-readable storage medium. The computer-readable storage medium stores a program that, when executed by a processor, can implement the simulation method for the gear shifting process of a hybrid powertrain as described in any of the above embodiments.

[0061] This invention can take the form of a computer program product implemented on one or more storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing program code. Computer-readable storage media include permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer-readable storage media include, but are not limited to: novel memories such as phase-change memory / resistive random access memory / magnetic memory / ferroelectric memory (PRAM / RRAM / MRAM / FeRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, read-only optical disc read-only memory (CD-ROM), digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transfer medium that can be used to store information accessible by a computing device.

[0062] The simulation method, apparatus, and computer-readable storage medium for the gear shifting process of a hybrid powertrain system provided in the embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the simulation method, apparatus, and computer-readable storage medium for the gear shifting process of a hybrid powertrain system according to the embodiments of the present invention. The descriptions of the above embodiments are only for helping to understand the core ideas of the present invention and are not intended to limit the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the spirit and principles of the present invention, and these improvements and modifications should all fall within the protection scope of the appended claims.

Claims

1. A method of simulating a hybrid driveline shift process, characterized by: The method comprises: establishing a one-dimensional torsional vibration model of the hybrid powertrain system under full throttle conditions; establishing a shift control strategy model in the acceleration process based on a shift map of the hybrid powertrain system under full throttle conditions, the shift control strategy model having a shift control strategy saved therein; jointly simulating based on the one-dimensional torsional vibration model and the shift control strategy model, comprising: transmitting engine speed, vehicle speed, engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque and B2 brake torque to the shift control strategy model; and the shift control strategy model outputting and feeding back corresponding engine speed and engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque and B2 brake torque to the one-dimensional torsional vibration model; and optimizing the shift control strategy and / or the hybrid powertrain system based on the simulation results.

2. The simulation method of claim 1, wherein: The method of establishing a one-dimensional torsional vibration model of the hybrid powertrain system under full throttle conditions comprises: collecting parameters of the hybrid powertrain system; determining a simplified approach of the hybrid powertrain system under full throttle conditions; and establishing a one-dimensional torsional vibration model of the hybrid powertrain system under full throttle conditions based on the parameters of the hybrid powertrain system and according to the simplified approach.

3. The simulation method of claim 2, wherein: The method of determining a simplified approach of the hybrid powertrain system under full throttle conditions comprises: model simplifying the hybrid powertrain system under full throttle conditions based on the axial torsional direction of the hybrid powertrain system and the inertia of the motor.

4. The emulation method of claim 1, wherein: The method of establishing a shift control strategy model in the acceleration process based on a shift map of the hybrid powertrain system under full throttle conditions comprises: establishing a shift control strategy model in the acceleration process based on a shift map of the hybrid powertrain system under full throttle conditions in a simulink platform.

5. The emulation method of claim 1, wherein: The method of jointly simulating based on the one-dimensional torsional vibration model and the shift control strategy model comprises: collecting load parameters of the hybrid powertrain system; and inputting the load parameters of the hybrid powertrain system into the one-dimensional torsional vibration model.

6. The emulation method of claim 5, wherein: The method of collecting load parameters of the hybrid powertrain system comprises: collecting cylinder pressure curves of the engine under full throttle conditions; collecting maximum torque curves of the P1 motor and the P3 motor; and determining corresponding vehicle speed and corresponding speed of the shift map upshift of the hybrid powertrain system under full throttle conditions.

7. The emulation method of claim 1, wherein: The shift control strategy comprises: judging whether it is in the shift process; when it is in the shift process, determining a shift time according to the shift map, entering a torque phase stage and performing torque phase control; after the torque phase control is completed, entering an inertia phase stage and performing inertia phase control; after the inertia phase stage is completed, switching the gear to a new gear; checking whether the engine torque, P1 motor torque, P3 motor torque, clutch torque, B1 brake torque and B2 brake torque exceed their respective torque capacities; and When it is confirmed that the engine torque, the P1 motor torque, the P3 motor torque, the clutch torque, the B1 brake torque and the B2 brake torque do not exceed the respective torque capacities, the engine torque, the P1 motor torque, the P3 motor torque, the clutch torque, the B1 brake torque and the B2 brake torque are introduced into the one-dimensional torsional vibration model.

8. The emulation method of claim 7, wherein: The shift control strategy further comprises: estimating a wheel end output torque; and acquiring torque changes of the engine, the P1 motor, the P3 motor, the clutch, the B1 brake and the B2 brake based on the wheel end output torque.

9. The emulation method of claim 7, wherein: The shift control strategy further comprises: in the torque phase, calculating the clutch torque and the B1 brake torque according to the engine torque, the P1 motor torque and the P3 motor torque, and determining a torque phase adjustment mode of the shift; and in the inertia phase, determining torque adjustment modes of the P1 motor, the P3 motor and the B2 brake according to the shift time requirement.

10. The emulation method of claim 1, wherein: The optimization of the shift control strategy and / or the hybrid power transmission system based on the simulation result comprises: evaluating each part of the hybrid power transmission system based on the simulation result; and optimizing the parts of the hybrid power transmission system and / or the shift control logic based on the evaluation result.

11. The emulation method of claim 10, wherein: The evaluation of each part of the hybrid power transmission system based on the simulation result comprises: checking whether there is excess or deficiency in the engine torque capacity, the clutch torque capacity, the B1 brake torque capacity, the B2 brake torque capacity and the torque capacity of the dual mass flywheel based on the simulation result.

12. A simulation device for a hybrid driveline shift process, characterized in that: one or more processors for implementing the simulation method of the shift process of the hybrid power transmission system according to any one of claims 1 to 11.

13. A computer-readable storage medium, characterized in that, a program stored thereon, which, when executed by a processor, implements the simulation method of the shift process of the hybrid power transmission system according to any one of claims 1 to 11.

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