Gear selection method, device and equipment of hybrid electric vehicle and computer medium

Abstract

The invention provides a gear selection method, device and equipment for a hybrid electric vehicle and a computer medium. The method comprises the steps that torque required by a driver and allowable discharging power of a battery are determined; obtaining the current rotating speed of the driving motor, and determining a high-efficiency working interval of the driving motor in the efficiency characteristics of the driving motor based on the equipower line corresponding to the allowable discharge power of the battery and the current rotating speed of the driving motor; determining a power boundary required to be provided by an engine based on the torque required by the driver and the torque upper and lower limits of the efficient working interval of the driving motor; determining an engine feasible region in the working characteristics of the engine by combining the power boundary; executing an equivalent fuel consumption minimum algorithm in the feasible region of the engine and the efficient working region of the driving motor, and determining optimal working points of the engine and the driving motor; and the wheel end rotating speed is obtained, and the synchronizer gear of the power dividing mechanism is controlled according to the relation between the engine rotating speed corresponding to the optimal working point and the wheel end rotating speed.

Description

Technical Field

[0001] This disclosure relates to the field of hybrid electric vehicle control technology, and in particular to a method, apparatus, device, and computer medium for selecting gears in a hybrid electric vehicle. Background Technology

[0002] Hybrid electric vehicles integrate two or more energy sources, including fuel chemical energy and battery electrical energy. Under the coordinated control of the vehicle's energy management strategy, they can achieve better fuel economy and lower emissions through various drive modes such as parallel, series, and power split. In parallel drive mode, gear selection must be closely integrated with the power allocated by the engine in energy management. The core of energy management lies in the selection of drive mode and the power distribution among various power sources.

[0003] Existing technologies often employ improved solutions based on the P1P3 architecture, with parallel engine drive featuring only two gears. The gear selection strategy is a common two-parameter shifting strategy, using vehicle speed and throttle opening as shift control parameters, and determining the shift line based on the goal of optimal power or economy under steady-state conditions. However, this existing technology has significant drawbacks: its shifting method is based on straight roads and steady-state driving conditions, failing to consider the current remaining battery charge and battery charging / discharging power of the hybrid vehicle; furthermore, the shift line does not adjust the shift points according to actual road conditions and drive motor torque, nor does it utilize a combined drive motor and engine torque sweeping algorithm with an equivalent fuel consumption optimization algorithm to ensure real-time optimal economy.

[0004] Furthermore, some existing hybrid powertrain systems replace the engine power source in the traditional series-parallel structure with a power-separated planetary gear mechanism. However, there are few reference cases for this structure and its corresponding control methods. Therefore, there is an urgent need for a method for power distribution and gear selection between the engine and motor in parallel drive systems adapted to this structure, in order to improve calculation speed while ensuring optimal fuel economy. Summary of the Invention

[0005] This disclosure aims to solve at least one of the technical problems existing in the prior art, and proposes a method, apparatus, device and computer medium for selecting gears in a hybrid electric vehicle.

[0006] In a first aspect, embodiments of this disclosure provide a gear selection method for a hybrid electric vehicle, applicable to hybrid systems including a power splitting mechanism, comprising the following steps:

[0007] The required torque for the driver is determined based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal; the allowable discharge power of the battery is determined based on the current remaining state of charge (SOC) and temperature of the battery.

[0008] The current speed of the drive motor is obtained, and based on the isopower line corresponding to the allowable discharge power of the battery and the current speed of the drive motor, the high-efficiency operating range of the drive motor is determined in the efficiency characteristics of the drive motor.

[0009] Based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor, the power boundary that the engine needs to provide is determined; combined with the power boundary, the feasible region of the engine is determined in the engine operating characteristics.

[0010] Within the feasible region of the engine and the efficient operating range of the drive motor, an equivalent fuel consumption minimization algorithm is executed to determine the optimal operating point of the engine and the drive motor.

[0011] The wheel end speed is obtained, and the synchronizer gear of the power splitting mechanism is controlled according to the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

[0012] In some embodiments, determining the driver's required torque includes: querying a preset two-dimensional MAP table of vehicle speed and accelerator pedal depth, and matching the current vehicle speed with the accelerator pedal depth to obtain the driver's required torque;

[0013] Determining the allowable discharge power of the battery includes: querying a preset SOC-temperature two-dimensional MAP table, and obtaining the allowable discharge power of the battery based on the current battery SOC and temperature.

[0014] In some embodiments, the high-efficiency operating range of the drive motor is the torque range corresponding to when the efficiency of the drive motor is not lower than a preset efficiency threshold.

[0015] The current speed of the drive motor is calculated based on the wheel end speed and the transmission ratio between the drive motor and the wheel end.

[0016] In some embodiments, the power boundary is determined by the difference between the driver's required torque and the upper and lower limits of the torque in the high-efficiency operating range of the drive motor, combined with the wheel-end speed conversion.

[0017] The feasible region of the engine is the operating condition region where the engine fuel consumption rate is lower than the preset fuel consumption threshold.

[0018] In some embodiments, the execution of the equivalent fuel consumption minimum algorithm includes:

[0019] Within the feasible region of the engine, a speed-torque search grid is established according to preset speed intervals and torque intervals; within the high-efficiency operating range of the drive motor, torque search points are established according to preset torque intervals.

[0020] Calculate the equivalent fuel consumption rate corresponding to the combination of each search grid node and torque search point, and select the operating point corresponding to the minimum value as the optimal operating point.

[0021] In some embodiments, the control synchronizer position includes:

[0022] The synchronizer is pre-set to engage the first gear with the first gear and the second gear with the second gear, wherein the first gear ratio is greater than the second gear ratio;

[0023] If the actual ratio of engine speed to wheel speed is greater than the first gear ratio, then the synchronizer is controlled to engage the first gear.

[0024] If the actual ratio is less than the second gear ratio, then engage the second gear;

[0025] If it falls between the two, place it in the middle position to achieve continuously variable transmission (CVT) mode.

[0026] In some embodiments, the method is executed once in each control cycle, and the control cycle is no more than 10 milliseconds.

[0027] Secondly, embodiments of this disclosure provide a gear selection device for a hybrid electric vehicle, the device comprising:

[0028] The first determining module is configured to determine the driver's required torque based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal; and to determine the battery's allowable discharge power based on the battery's current remaining charge (SOC) and temperature.

[0029] The second determining module is configured to obtain the current speed of the drive motor, and determine the high-efficiency operating range of the drive motor based on the isopower line corresponding to the allowable discharge power of the battery and the current speed of the drive motor in the efficiency characteristics of the drive motor.

[0030] The third determining module is configured to determine the power boundary that the engine needs to provide based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor; and to determine the engine's feasible domain in the engine's operating characteristics in combination with the power boundary.

[0031] The fourth determining module is configured to execute an equivalent fuel consumption minimization algorithm within the engine's feasible region and the drive motor's efficient operating range to determine the optimal operating point of the engine and drive motor.

[0032] The control module is configured to acquire the wheel end speed and control the synchronizer gear of the power splitting mechanism based on the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

[0033] Thirdly, embodiments of this disclosure provide an electronic device, including:

[0034] One or more processors;

[0035] Memory, used to store one or more programs;

[0036] When one or more programs are executed by one or more processors, the one or more processors implement the gear selection method for hybrid vehicles provided in the first aspect.

[0037] Fourthly, embodiments of this disclosure provide a computer-readable medium storing a computer program that, when executed by a processor, implements the gear selection method for a hybrid electric vehicle provided in the first aspect.

[0038] The gear selection method for hybrid electric vehicles disclosed herein achieves multi-parameter coordinated gear selection by sequentially determining the required torque, battery discharge power, motor high-efficiency range, engine power boundary, optimal operating point, and gear control through a complete logic chain. This method is compatible with special hybrid systems that include power splitting mechanisms, ensures fuel economy through an equivalent fuel consumption minimization algorithm, and controls the gear based on the relationship between engine and wheel speeds to ensure precise matching of power output and driving conditions. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the structure of a P1P3 architecture hybrid power system in the prior art;

[0040] Figure 2 This is a schematic diagram of the structure of a multi-gear hybrid power transmission system provided in an embodiment of the present disclosure;

[0041] Figure 3 A schematic flowchart illustrating a gear selection method for a hybrid electric vehicle provided in this embodiment of the present disclosure;

[0042] Figure 4 A drive motor efficiency map provided for embodiments of this disclosure;

[0043] Figure 5 Engine characteristic curves provided for embodiments of this disclosure;

[0044] Figure 6 A schematic diagram of the structure of a gear selection device for a hybrid electric vehicle provided in an embodiment of this disclosure;

[0045] Figure 7 This is a structural block diagram of an electronic device provided in an embodiment of the present disclosure. Detailed Implementation

[0046] To enable those skilled in the art to better understand the technical solutions of this disclosure, exemplary embodiments of this disclosure are described below with reference to the accompanying drawings, including various details of the embodiments of this disclosure to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this disclosure. Similarly, for clarity and conciseness, descriptions of well-known functions and structures are omitted in the following description.

[0047] Where there is no conflict, the various embodiments of this disclosure and the features thereof in the embodiments may be combined with each other.

[0048] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0049] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Words such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0050] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and this disclosure, and will not be interpreted as having an idealized or overly formal meaning, unless expressly so defined herein.

[0051] The collection, storage, use, processing, transmission, provision, and disclosure of user personal information in this technical solution comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example, appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely identifying specific individuals.

[0052] With increasingly stringent requirements for energy conservation and emission reduction, hybrid vehicles have become an important development direction for the automotive industry. Hybrid vehicles typically possess two or more energy sources: fuel chemical energy and battery electrical energy. Under the coordinated control of the vehicle's energy management strategy, based on current road condition information, the various power sources cooperate with each other to form multiple driving modes such as parallel, series, or power split, in order to achieve optimal fuel economy and emission performance.

[0053] In parallel drive mode, gear selection needs to take into account the power allocated by the engine in energy management. The core issue of energy management lies in the selection of drive mode and the power distribution of each power source. Figure 1 This is a schematic diagram of the structure of a P1P3 architecture hybrid power system in the prior art, such as... Figure 1 As shown, for parallel hybrid systems with a P1P3 architecture, a two-parameter shifting strategy using vehicle speed and throttle opening as control parameters is commonly adopted, with shift lines determined based on the optimal power or economy target under steady-state conditions. This strategy has the following drawbacks:

[0054] First, the shifting method is based on straight roads and steady-state driving conditions, failing to take into account key state parameters such as battery state of charge (SOC) and battery charging and discharging power. Second, the shift lines cannot dynamically adjust the shift points according to the torque of the drive motor under actual road conditions, and do not consider using the Equivalent Consumption Minimization Strategy (ECMS) to optimize real-time economy through coordinated optimization of drive motor and engine torque. Third, the traditional ECMS algorithm requires a global search across the entire operating space of the engine and motor, resulting in a huge computational load that is difficult to meet the real-time requirements of the vehicle controller, thus limiting its practical application.

[0055] Furthermore, hybrid systems that use a power-separated planetary gear mechanism (similar to Toyota's THS system) to replace the engine's direct-drive path in traditional series-parallel structures have a unique power coupling method: engine power is transmitted to the wheel ends via the planetary gear mechanism, coupling with the drive motor power at the wheel ends. Because this structure is rarely used in the market, there is a lack of reference documents for efficient, real-time energy management and control strategies adapted to it in existing technologies, resulting in its potential not being fully realized.

[0056] To address at least one or more of the aforementioned technical problems, embodiments of this disclosure provide a gear selection method for hybrid electric vehicles. By pre-locating the high-efficiency operating areas of the engine and drive motor, the search space of the ECMS algorithm is reduced, significantly improving the controller's processing speed while ensuring fuel economy and meeting real-time control requirements.

[0057] Figure 2This is a schematic diagram of a multi-speed hybrid powertrain system provided in an embodiment of this disclosure. Figure 2 As shown, this system replaces the engine power source with a power-separated planetary gear mechanism, with the drive motor directly driving the wheel ends. Engine power is distributed and transmitted through the planetary gear mechanism, coupling with the drive motor power at the wheel ends. The synchronizer is located at the output end of the planetary gear mechanism and has three positions: left, right, and middle, corresponding to two fixed transmission ratios and the ECVT mode, respectively. This structure allows for decoupling of engine speed and vehicle speed, providing greater flexibility for energy management optimization.

[0058] Figure 3 This is a flowchart illustrating a gear selection method for a hybrid electric vehicle provided in an embodiment of the present disclosure, as shown below. Figure 3 As shown, the method includes steps S1-S5:

[0059] Step S1: Determine the driver's required torque based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal; determine the battery's allowable discharge power based on the battery's current remaining charge (SOC) and temperature.

[0060] Step S2: Obtain the current speed of the drive motor. Based on the isopower line corresponding to the battery's allowable discharge power and the current speed of the drive motor, determine the high-efficiency operating range of the drive motor in the drive motor efficiency characteristics.

[0061] Step S3: Based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor, determine the power boundary that the engine needs to provide; and combine the power boundary to determine the feasible region of the engine in the engine operating characteristics.

[0062] Step S4: Execute the equivalent fuel consumption minimum algorithm within the feasible region of the engine and the efficient operating range of the drive motor to determine the optimal operating point of the engine and the drive motor.

[0063] Step S5: Obtain the wheel end speed, and control the synchronizer gear of the power splitting mechanism according to the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

[0064] The gear selection method for hybrid electric vehicles provided in this disclosure is applicable to hybrid systems including planetary gear power splitting mechanisms. This type of system differs from the traditional P1P3 architecture; its engine power path uses a planetary gear mechanism to achieve power splitting, and the drive motor power and the split power from the engine are coupled at the wheel ends. The method first simultaneously acquires two types of key input parameters: one is the vehicle speed and accelerator pedal depth, reflecting the driver's intention, used to determine the driver's required torque Tdrv; the other is the state of charge (SOC) and temperature, reflecting the battery's state, used to determine the battery's allowable discharge power Pk. In this way, dynamic operating condition information and battery capacity constraints can be incorporated into the control system. Compared to the traditional two-parameter shifting strategy based solely on steady-state conditions, this method can more accurately respond to actual driving needs and ensure system safety boundaries. This solution achieves synergistic optimization of fuel economy and control response speed based on multi-dimensional parameter acquisition, efficient operating range positioning, optimal operating point calculation, and gear adaptive control.

[0065] In some embodiments, in step S1, determining the driver's required torque includes: querying a preset two-dimensional MAP table of vehicle speed-accelerator pedal depth, and matching the current vehicle speed with the accelerator pedal depth to obtain the driver's required torque; determining the battery's allowable discharge power includes: querying a preset two-dimensional MAP table of SOC-temperature, and matching the current battery SOC with the temperature to obtain the battery's allowable discharge power.

[0066] It should be understood that the MAP table is based on battery characteristic test data and can accurately reflect the battery's power capability under different states of charge and temperatures. Therefore, using the lookup table method can quickly obtain parameters, avoiding complex real-time calculations and improving the controller's response speed. By combining precise offline calibration with online table lookup, both the accuracy of parameter acquisition and the time requirements of real-time control are met.

[0067] In some embodiments, the high-efficiency operating range of the drive motor in step S2 is the torque range corresponding to when the efficiency of the drive motor is not lower than a preset efficiency threshold; the current speed of the drive motor is calculated based on the wheel end speed and the transmission ratio between the drive motor and the wheel end.

[0068] The above method can eliminate inefficient operating points by screening through efficiency thresholds, providing optimal space for subsequent power allocation. By converting the transmission ratio, the correspondence between motor speed and vehicle speed can be accurately established, thereby clarifying the efficient operating boundary of the motor and providing an accurate speed reference for calculating engine power requirements.

[0069] In some embodiments, the power boundary in step S3 is determined by the difference between the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor, combined with the wheel end speed conversion; the feasible region of the engine is the operating condition area when the engine fuel consumption rate is lower than the preset fuel consumption threshold.

[0070] Specifically, the power boundary is determined by the difference between the torque required by the driver and the upper and lower limits Te1 and Te2 of the torque in the efficient operating range of the drive motor, combined with the wheel end speed. The lower limit of the torque that the engine needs to supplement is Tdrv-Te2, and the upper limit is Tdrv-Te1. Combined with the wheel end speed, it can be converted into the power boundary P_ice1~P_ice2. The feasible region of the engine is defined as the operating condition area where the engine fuel consumption rate is lower than the preset threshold.

[0071] Figure 4 The drive motor efficiency map provided in the embodiments of this disclosure is as follows: Figure 4 As shown, the horizontal axis represents the motor speed nm (in rpm), and the vertical axis represents the motor torque Te (in Nm). The graph includes iso-efficiency circles (such as 80%, 85%, and 90% efficiency lines) and iso-power lines Pk. The intersection of the preset efficiency threshold ηth (such as 85%) and the iso-power line Pk determines the torque boundaries Te1 and Te2. The area within these boundaries is the high-efficiency operating range of the drive motor. This graph visually demonstrates how to quickly lock the high-efficiency torque range of the motor based on the battery power capacity Pk and the motor speed nm, avoiding the motor operating in the inefficient region when calculating engine power requirements.

[0072] Figure 5 The engine characteristic curves provided in the embodiments of this disclosure are as follows: Figure 5 As shown, the horizontal axis represents engine speed *ne*, and the vertical axis represents engine torque *Te*. The figure includes constant fuel consumption zones (e.g., 220 g / kWh, 240 g / kWh) and constant power lines *P_ice1* and *P_ice2*. The region enclosed by the constant power lines corresponding to power boundaries *P_ice1* and *P_ice2* and the preset fuel consumption threshold is the engine's feasible region *A_ice*. This figure illustrates how to filter out the operating conditions of the engine that meet power requirements and achieve optimal fuel consumption by using power boundaries, thus providing a search range for local point scanning.

[0073] The method provided in this disclosure uses the motor torque range to infer the torque gap that the engine must handle, then converts the torque requirement into a power requirement to match the engine's actual capacity; furthermore, it filters out high-fuel-consumption operating conditions based on fuel consumption thresholds. This quickly identifies the power range that the engine needs to engage and narrows the search space from all operating conditions to a highly efficient feasible region, laying the foundation for localized point scanning.

[0074] In some embodiments, executing the equivalent fuel consumption minimum algorithm in step S4 includes:

[0075] Within the feasible region of the engine, a speed-torque search grid is established according to preset speed and torque intervals. Within the efficient operating range of the drive motor, torque search points are established according to preset torque intervals. The equivalent fuel consumption rate corresponding to the combination of each search grid node and torque search point is calculated, and the operating point corresponding to the minimum value is selected as the optimal operating point.

[0076] In one example, the equivalent fuel consumption rate mef = mfuel + λ·Pbat, where mfuel is the engine's instantaneous fuel consumption rate (g / s), Pbat is the battery power (kW, positive for discharging, negative for charging), and λ is the equivalence factor (g / kWh), which equates electrical energy consumption to fuel consumption. The equivalence factor λ is dynamically adjusted based on the current State of Charge (SOC): when the SOC is low, λ increases, causing the algorithm to favor engine power; when the SOC is high, λ decreases, causing the algorithm to favor motor power, thus achieving SOC balance. During local point scanning, mfuel and Pbat are calculated for each speed-torque search point to obtain mef, and the point with the smallest mef is selected as the optimal operating point.

[0077] In this embodiment, the operation areas of the engine and drive motor are initially located, and then the operating points of the engine and drive motor are precisely determined by refining the grid. This two-level search process, which combines initial location and grid refinement, specifically includes: the first level is region pre-screening, which determines the range of the motor line and the range of the engine surface by using isopower lines and efficiency / fuel consumption thresholds; the second level is grid refinement, which establishes dense search points in the pre-screened area at small intervals (e.g., speed interval of 50 rpm, torque interval of 2 Nm) and performs ECMS calculations.

[0078] By replacing the traditional global search across the entire operating space with a pre-selected local point scan, the computational load can be significantly reduced; the preset grid interval balances search accuracy and computational load. While ensuring optimization accuracy, the computational load is significantly reduced, enabling the ECMS algorithm to complete within a 10ms control cycle, meeting the real-time requirements of the vehicle controller.

[0079] In some embodiments, controlling the synchronizer gear position in step S5 includes: presetting a first gear ratio corresponding to the synchronizer engaging a first gear and a second gear ratio corresponding to the synchronizer engaging a second gear, wherein the first gear ratio is greater than the second gear ratio; if the actual ratio of the engine speed to the wheel end speed is greater than the first gear ratio, then the synchronizer is controlled to engage the first gear; if the actual ratio is less than the second gear ratio, then the second gear is engaged; if it is between the two, then it is placed in the middle position to achieve continuously variable transmission mode.

[0080] Specifically, the synchronizer is preset to engage the first gear with a first gear ratio K1 and the second gear with a second gear ratio K2, where K1 > K2. If the actual ratio of engine speed to wheel speed is greater than K1, the first gear (high speed) is engaged. If the actual ratio of engine speed to wheel speed is less than K2, the second gear (low speed) is engaged. If the actual ratio of engine speed to wheel speed is between K1 and K2, the system is placed in the middle position to achieve ECVT continuously variable transmission mode.

[0081] The above method directly links the engine's optimal operating speed requirement with the transmission system gear. By selecting the gear, the engine can operate at the optimal speed point determined by the ECMS algorithm, achieving a deep integration of gear selection and energy management strategy. This ensures that the engine always operates under the system's optimal conditions while improving fuel economy.

[0082] It should also be noted that the synchronizer's gear selection does not follow a fixed shift line, but is dynamically adjusted entirely based on the ECMS optimization results. Different gears may be selected in each control cycle, ensuring that the engine speed always tracks the optimal operating point, unlike traditional strategies where gear switching lags behind changes in operating conditions. In practice, the control unit needs to store the gear state from the previous cycle. If the optimal gear calculated for the current cycle differs from the previous cycle, the synchronizer engagement / disengagement control logic must be executed, including four stages: torque reduction, speed synchronization, gear switching, and torque recovery, ensuring a smooth and shock-free switching process.

[0083] Furthermore, due to the rapid changes in the operating conditions of the hybrid system, a longer control cycle will cause the gear selection to lag and deviate from the optimal operating point; the 10ms cycle is the engineering optimal value determined based on the computing power of the vehicle controller and the CAN bus communication rate.

[0084] Based on this, in some embodiments, the gear selection method for hybrid electric vehicles provided in this disclosure is executed once per control cycle, with the control cycle not exceeding 10 milliseconds. This ensures real-time synchronization between gear selection and power distribution, enabling the vehicle to respond promptly to changes in operating conditions and maintain the system continuously operating in the high-efficiency zone.

[0085] In summary, the gear selection method for hybrid electric vehicles provided in this disclosure proposes a "power-efficiency" dual-constraint pre-screening mechanism, reducing the three-dimensional search space (speed-torque-power) to a local region search, thus solving the real-time application challenge of the ECMS algorithm in multi-gear planetary gear hybrid systems. This mechanism retains the global optimality of ECMS while avoiding invalid calculations through regional pre-screening, achieving a balance between optimality and real-time performance—a technical effect that neither existing two-parameter shifting strategies nor global ECMS algorithms can achieve. Furthermore, this method is deeply compatible with planetary gear power splitting mechanisms, achieving precise matching of engine speed requirements through synchronizer three-position control, thus addressing the issues of limited reference documentation and high optimization difficulty associated with this control strategy.

[0086] Figure 6 This is a schematic diagram of the structure of a gear selection device for a hybrid electric vehicle provided in an embodiment of this disclosure, as shown below. Figure 6 As shown, the control device includes:

[0087] The first determining module 10 is configured to determine the driver's required torque based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal; and to determine the allowable discharge power of the battery based on the current remaining charge (SOC) and temperature of the battery.

[0088] The second determining module 20 is configured to obtain the current speed of the drive motor, and determine the high-efficiency operating range of the drive motor based on the isopower line corresponding to the allowable discharge power of the battery and the current speed of the drive motor in the efficiency characteristics of the drive motor.

[0089] The third determining module 30 is configured to determine the power boundary that the engine needs to provide based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor; and to determine the engine's feasible domain in the engine's operating characteristics in combination with the power boundary.

[0090] The fourth determining module 40 is configured to execute an equivalent fuel consumption minimum algorithm within the feasible region of the engine and the efficient operating range of the drive motor to determine the optimal operating point of the engine and the drive motor.

[0091] The control module 50 is configured to acquire the wheel end speed and control the synchronizer gear of the power splitting mechanism according to the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

[0092] The gear selection device for hybrid electric vehicles provided in this disclosure achieves multi-parameter coordinated gear selection by sequentially determining the required torque, battery discharge power, motor high-efficiency range, engine power boundary, optimal operating point, and gear control through a complete logic chain. It is compatible with special hybrid systems that include power splitting mechanisms, ensures fuel economy through an equivalent fuel consumption minimization algorithm, and controls the gear based on the relationship between engine and wheel speed to ensure precise matching of power output and driving conditions.

[0093] Based on the same inventive concept, this disclosure also provides an electronic device. Figure 7 This is a structural block diagram of an electronic device provided in an embodiment of this disclosure. Figure 7 As shown, this disclosure provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement a gear selection method for any of the hybrid electric vehicles described above; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0094] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0095] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0096] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0097] This disclosure also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps in the gear selection method for any of the hybrid electric vehicles described above. The computer-readable storage medium may be volatile or non-volatile.

[0098] This disclosure also provides a computer program product, including computer-readable code, or a non-volatile computer-readable storage medium carrying computer-readable code, wherein when the computer-readable code is run in the processor of an electronic device, the processor in the electronic device executes the above-described gear selection method for a hybrid electric vehicle.

[0099] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0100] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0101] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0102] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0103] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0104] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0105] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0106] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0107] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0108] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in connection with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in connection with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of this disclosure as set forth by the appended claims.

Claims

1. A method for selecting gears in a hybrid electric vehicle, applicable to a hybrid system including a power splitting mechanism, characterized in that, Includes the following steps: The required torque for the driver is determined based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal. Determine the battery's allowable discharge power based on its current remaining state of charge (SOC) and temperature. The current speed of the drive motor is obtained, and based on the isopower line corresponding to the allowable discharge power of the battery and the current speed of the drive motor, the high-efficiency operating range of the drive motor is determined in the efficiency characteristics of the drive motor. Based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor, the power boundary that the engine needs to provide is determined; combined with the power boundary, the feasible region of the engine is determined in the engine operating characteristics. Within the feasible region of the engine and the efficient operating range of the drive motor, an equivalent fuel consumption minimization algorithm is executed to determine the optimal operating point of the engine and the drive motor. The wheel end speed is obtained, and the synchronizer gear of the power splitting mechanism is controlled according to the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

2. The method according to claim 1, characterized in that, The process of determining the driver's required torque includes: querying a preset two-dimensional MAP table of vehicle speed and accelerator pedal depth, and matching the current vehicle speed with the accelerator pedal depth to obtain the driver's required torque; Determining the allowable discharge power of the battery includes: querying a preset SOC-temperature two-dimensional MAP table, and obtaining the allowable discharge power of the battery based on the current battery SOC and temperature.

3. The method according to claim 1, characterized in that, The high-efficiency operating range of the drive motor is the torque range corresponding to when the efficiency of the drive motor is not lower than a preset efficiency threshold. The current speed of the drive motor is calculated based on the wheel end speed and the transmission ratio between the drive motor and the wheel end.

4. The method according to claim 1, characterized in that, The power boundary is determined by the difference between the driver's required torque and the upper and lower limits of the torque in the high-efficiency operating range of the drive motor, combined with the wheel end speed. The feasible region of the engine is the operating condition region where the engine fuel consumption rate is lower than the preset fuel consumption threshold.

5. The method according to claim 1, characterized in that, The algorithm for minimizing equivalent fuel consumption includes: Within the feasible region of the engine, a speed-torque search grid is established according to preset speed intervals and torque intervals; within the high-efficiency operating range of the drive motor, torque search points are established according to preset torque intervals. Calculate the equivalent fuel consumption rate corresponding to the combination of each search grid node and torque search point, and select the operating point corresponding to the minimum value as the optimal operating point.

6. The method according to claim 1, characterized in that, The control synchronizer settings include: The synchronizer is pre-set to engage the first gear with the first gear and the second gear with the second gear, wherein the first gear ratio is greater than the second gear ratio; If the actual ratio of engine speed to wheel speed is greater than the first gear ratio, then the synchronizer is controlled to engage the first gear. If the actual ratio is less than the second gear ratio, then engage the second gear; If it falls between the two, place it in the middle position to achieve continuously variable transmission (CVT) mode.

7. The method according to claim 1, characterized in that, The method is executed once in each control cycle, and the control cycle is no more than 10 milliseconds.

8. A gear selection device for a hybrid electric vehicle, characterized in that, The device includes: The first determining module is configured to determine the driver's required torque based on the current driving speed of the hybrid vehicle and the depth of the accelerator pedal; and to determine the battery's allowable discharge power based on the battery's current remaining charge (SOC) and temperature. The second determining module is configured to obtain the current speed of the drive motor, and determine the high-efficiency operating range of the drive motor based on the isopower line corresponding to the allowable discharge power of the battery and the current speed of the drive motor in the efficiency characteristics of the drive motor. The third determining module is configured to determine the power boundary that the engine needs to provide based on the driver's required torque and the upper and lower limits of the torque in the efficient operating range of the drive motor; and to determine the engine's feasible domain in the engine's operating characteristics in combination with the power boundary. The fourth determining module is configured to execute an equivalent fuel consumption minimization algorithm within the engine's feasible region and the drive motor's efficient operating range to determine the optimal operating point of the engine and drive motor. The control module is configured to acquire the wheel end speed and control the synchronizer gear of the power splitting mechanism based on the relationship between the engine speed corresponding to the optimal operating point and the wheel end speed.

9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the gear selection method for a hybrid electric vehicle as described in any one of claims 1 to 7.

10. A computer-readable medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps in the gear selection method for a hybrid electric vehicle as described in any one of claims 1 to 7.

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