Gear shifting control method, system, equipment and medium

Abstract

The invention provides a gear shifting control method, system and device and a medium, and belongs to the technical field of commercial vehicle gear shifting, the method comprises the steps that various vehicle parameters such as VCU demand torque are collected in real time, and accordingly the wheel end torque T0 needed by current driving of a vehicle, the vehicle available wheel end torque allowance Ta under the current gear and the vehicle available wheel end torque allowance Tb under the target gear are estimated; and judging the relationship between Ta and an upshift set value a0, and determining whether to upshift or not according to the judgment of Tb and a target gear set value c, or determining whether to downshift or not according to the relationship between Ta and a downshift set value b0. And after gear shifting is completed, whether Ta is between b0 and a0 or not is judged so as to determine whether gear shifting is finished or not. The gear shifting opportunity can be accurately controlled according to the real-time running state of the vehicle, motor power is fully utilized, the vehicle can be kept at a proper gear under different working conditions, the power performance and driving comfort are improved, and the energy utilization efficiency is improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of commercial vehicle gear shifting, and particularly relates to a gear shifting control method, system, device and medium. BACKGROUND

[0002] With the rapid development of new energy vehicles, especially pure electric vehicles and hybrid electric vehicles, the electric drive system has become the core component of the vehicle powertrain. Unlike traditional internal combustion engine vehicles, electric vehicles usually use single-stage reducers or are equipped with multi-gear automatic transmissions to meet the needs of low-speed high-torque and high-speed high-efficiency. In a multi-gear electric drive system, the gear shifting control strategy directly affects the power, economy, smoothness and driving comfort of the vehicle.

[0003] In the related art, the gear shifting execution mode is based on vehicle speed, motor speed or throttle opening to determine whether to execute gear shifting. If the vehicle speed is 60km / h when driving on a flat road, the gear can be shifted up, but when climbing a slope, the required traction at the wheel end is greater at the same vehicle speed. If the gear is shifted up only according to the vehicle speed, the motor output torque will be insufficient after the gear is shifted up, the vehicle power will suddenly drop, the vehicle will be unable to climb, and even be forced to shift down, resulting in frequent gear shifting and poor driving experience.

[0004] The related art terminates the process after completing the upshift / downshift, and does not verify whether the power redundancy of the new gear is within a reasonable range. That is, although the power is temporarily improved after downshifting, the power redundancy may be too large due to excessive downshifting, thereby triggering unnecessary upshift; or the power redundancy is insufficient after upshifting due to changes in road conditions, immediately downshifting, resulting in frequent actions of gear shifting-again gear shifting, and reducing the driving smoothness. SUMMARY

[0005] The application provides a gear shifting control method, which realizes precise gear shifting control, improves the smoothness of power connection, enhances the ability of the vehicle to cope with complex working conditions, and optimizes the user experience.

[0006] The method comprises the following steps: S101: Real-time acquisition of VCU demand torque, demand gear, speed ratio information, vehicle speed and motor torque; S102: Estimating the wheel end torque T0 required by the vehicle currently driving according to the acquired VCU demand torque, demand gear, speed ratio information, vehicle speed and motor torque; S103: Estimating the available wheel end torque margin Ta of the vehicle in the current gear according to the current gear, the current motor speed and the current motor torque at the current vehicle speed; S104: Estimating the motor speed of the target gear at the current vehicle speed, the maximum torque available at the motor speed of the target gear, and then calculating the available wheel end torque margin Tb of the vehicle in the target gear; S105: judging whether the wheel end torque margin Ta is greater than or equal to the current gear upshift torque margin setting value a0, if yes, executing step S106, if not, executing step S107; S106: judging whether the wheel end torque margin Tb is greater than or equal to the target gear torque margin setting value c, if yes, controlling the vehicle to upshift, if not, controlling the vehicle to keep the current gear; S107: judging whether the wheel end torque margin Ta is less than the current gear downshift torque margin setting value b0, if yes, controlling the vehicle to downshift, if not, controlling the vehicle to keep the current gear; S108: after completing upshift or downshift, judging whether the wheel end torque margin Ta satisfies b0<Ta<a0, if yes, controlling the end of gear shifting.

[0007] It is further needed to be explained that S102 specifically includes the following steps: extracting the VCU demand torque, the current motor torque, the transmission ratio corresponding to the current gear, the reducer ratio and the vehicle speed parameters; multiplying the transmission ratio of the current gear and the reducer ratio to obtain the total speed ratio of the current transmission system; obtaining the transmission system efficiency parameter under the current working condition according to the current gear, the vehicle speed and the preset transmission efficiency mapping table; multiplying the current motor torque and the total speed ratio, and then multiplying the transmission system efficiency parameter to obtain the preliminary wheel end torque; correcting the preliminary wheel end torque according to the deviation between the VCU demand torque and the preliminary wheel end torque to obtain the wheel end torque T0 required for the current vehicle driving.

[0008] It is further needed to be explained that S103 specifically includes the following steps: obtaining the transmission system speed ratio information corresponding to the current gear, the speed ratio being the product of the main box speed ratio and the auxiliary box speed ratio of the current gear; obtaining the maximum available motor torque under the current speed from the motor torque-speed characteristic curve or the real-time data of the motor controller; obtaining the pre-calibrated total efficiency of the transmission system; calculating the maximum wheel end torque that the motor can provide under the current gear, multiplying the current maximum available motor torque by the current gear speed ratio, and then multiplying the total efficiency of the transmission system; obtaining the current driving required wheel end torque T0 estimated in step S102, subtracting T0 from the obtained maximum wheel end torque to obtain the available wheel end torque margin Ta of the vehicle under the current gear.

[0009] It is further needed to be explained that S104 specifically includes the following steps: The current vehicle speed pulse signal is collected through the vehicle speed sensor interface circuit, and a digital vehicle speed value is obtained after signal conditioning and analog-to-digital conversion. According to the current gear state and the preset gear shifting rule, a target gear value is determined from a gear shifting strategy table. The target gear value is taken as an index to read a corresponding target gear total speed ratio parameter from the memory. The current vehicle speed value and the target gear total speed ratio are input into a vehicle controller to calculate a theoretical motor speed value under the target gear. The calculated target gear motor speed theoretical value is taken as an index to query a motor external characteristic MAP table to obtain a corresponding maximum torque, and the target gear total speed ratio is combined to calculate a theoretical maximum wheel end torque, which is then subjected to subtraction operation with a required wheel end torque T0 to obtain a vehicle available wheel end torque margin Tb under the target gear.

[0010] It is further needed to be explained that S105 specifically includes the following steps: The wheel end torque margin Ta of the current gear is extracted from the calculation result storage area of step S103, and the upshift torque margin setting value a0 corresponding to the current gear is called from the preset parameter library of the vehicle control system. The extracted wheel end torque margin Ta and the upshift torque margin setting value a0 are subjected to parameter validity check, it is checked whether Ta is within the range of 0 to the maximum wheel end torque margin of the vehicle, and it is confirmed that a0 matches the identification information of the current gear. The wheel end torque margin Ta and the upshift torque margin setting value a0 are subjected to numerical value comparison through the comparison logic unit of the vehicle controller. According to the comparison result, a corresponding flow trigger signal is generated, if Ta is greater than or equal to a0, an upshift judgment flow trigger signal is generated, and if Ta is less than a0, a downshift judgment flow trigger signal is generated.

[0011] It is further needed to be explained that S106 specifically includes the following steps: The value of the target gear wheel end torque margin Tb calculated in step S104 is read from the memory. The target gear value is taken as an index to read a corresponding c value from the target gear torque margin setting value mapping table stored in the memory. The Tb value and the c value are input into the vehicle controller to perform greater than or equal to comparison operation. According to the comparison result, a control decision signal is generated, if Tb≥c, an upshift control instruction is generated, otherwise a gear holding control instruction is generated. The control instruction is transmitted to the gear shifting actuator controller to drive the corresponding electromagnetic valve or motor to perform upshift or holding action.

[0012] It is further needed to be explained that S108 specifically includes the following steps: After the upshift or downshift action is completed, the wheel end torque margin Ta under the new current gear is re-estimated, and the downshift torque margin setting value b0 and the upshift torque margin setting value a0 corresponding to the new current gear are retrieved from the memory; S1082: The re-acquired wheel end torque margin Ta, downshift setting value b0 and upshift setting value a0 are subjected to parameter validity check, it is checked whether Ta is within the range of 0 to the maximum wheel end torque margin of the new current gear, and it is confirmed that b0 is less than a0 and both match the identification information of the new current gear; S1083: Through the vehicle controller, it is first judged whether the wheel end torque margin Ta is greater than the downshift setting value b0, and then it is judged whether Ta is less than the upshift setting value a0; S1084: According to the comprehensive results of the two judgments, a control signal is generated, if Ta is greater than b0 and less than a0 at the same time, a shift end control signal is generated, if it is not satisfied at the same time, a continue monitoring control signal is generated; S1085: The generated control signal is transmitted through the vehicle control main bus, if it is a shift end signal, the shift process is terminated, if it is a continue monitoring signal, the next round of wheel end torque margin acquisition and judgment is triggered.

[0013] The application also provides a shift control system, the system comprising: An information acquisition module is configured to acquire VCU demand torque, demand gear, speed ratio information, vehicle speed and motor torque in real time; A torque estimation module is configured to estimate the wheel end torque T0 required by the vehicle currently driving according to the acquired VCU demand torque, demand gear, speed ratio information, vehicle speed and motor torque; A gear margin estimation module is configured to estimate the available wheel end torque margin Ta of the vehicle under the current gear at the current vehicle speed, the current motor speed and the current motor torque; A gear available estimation module is configured to estimate the motor speed of the target gear at the current vehicle speed, the maximum torque available at the motor speed of the target gear, and further calculate the available wheel end torque margin Tb of the vehicle under the target gear; An upshift judgment module is configured to judge whether the wheel end torque margin Ta is greater than or equal to the upshift torque margin setting value a0 of the current gear, if yes, an upshift execution module is executed, if not, a downshift execution module is executed; An upshift execution module is configured to judge whether the wheel end torque margin Tb is greater than or equal to the torque margin setting value c of the target gear, if yes, the vehicle is controlled to upshift, if not, the vehicle is controlled to keep the current gear; A downshift execution module is configured to judge whether the wheel end torque margin Ta is less than the downshift torque margin setting value b0 of the current gear, if yes, the vehicle is controlled to downshift, if not, the vehicle is controlled to keep the current gear; A shift determination module is configured to determine whether the wheel end torque margin Ta satisfies b0<Ta<a0 after the upshift or downshift is completed, and control the shift to end if so.

[0014] According to another embodiment of the present application, an electronic device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of the shift control method when executing the program.

[0015] According to yet another embodiment of the present application, a storage medium is also provided, having a computer program stored thereon, wherein the computer program is executable by a processor to implement the steps of the shift control method.

[0016] As can be seen from the above technical solutions, the present application has the following advantages: The shift control method provided by the present application quantifies the power redundancy of the current and target gears through the wheel end torque margin, ensuring that the upshift / downshift action matches the actual power demand. The torque margin Tb of the target gear is verified before upshift to determine whether it satisfies the set value c, thereby avoiding a sudden drop in power after upshift. The current gear Ta is judged based on whether it is lower than b0 during downshift to ensure that the power is replenished in time after downshift. Through the closed-loop verification of b0<Ta<a0, the power redundancy of the final gear is within a reasonable range, reducing unnecessary shift actions and reducing wear and energy loss of the transmission system.

[0017] The present application comprehensively considers the VCU demand torque, motor torque, speed ratio, and other parameters, and can cover different working conditions such as acceleration, deceleration, climbing, and flat road, ensuring accurate shifting when the load and road conditions change. The shift timing is accurately matched with the actual power demand and driving conditions of the vehicle, ensuring sufficient power and driving smoothness, and improving economy and working condition adaptability. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the present application, the following will briefly introduce the drawings needed to be used in the description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Figure 1 The shift control method flowchart; Figure 2 The shift control method embodiment flowchart; Figure 3 The shift control system schematic diagram; Figure 4 The electronic device schematic diagram. DETAILED DESCRIPTION

[0020] The shift control method provided by the application calculates the wheel end torque T0 required by the current vehicle running, i.e. the traction force, by the VCU required torque collected through the bus, the torque and the motor speed fed back by the motor, the gear ratio and the reducer ratio of each gear stored in the memory and the wheel parameters. The current wheel end torque margin T a is calculated by the current bus data of the vehicle running. b T a and T b When the conditions in the flow chart are met, the operation of upshifting, downshifting or keeping the gear unchanged is performed.

[0021] The shift control method related to the application will be described in detail below. For the purpose of illustration but not for the purpose of limitation, specific details such as specific system structures, techniques, etc. are presented in order to thoroughly understand the embodiments of the application. However, it should be clear to those skilled in the art that the application can also be implemented in other embodiments without these specific details.

[0022] It should be understood that when used in the specification of the application, the term includes indicates the existence of the described features, whole, steps, operations, elements and / or components, but does not exclude the existence or addition of one or more other features, whole, steps, operations, elements, components and / or their collection. The terms include, contain, have and their variants mean to include but not limited to, unless otherwise specifically emphasized.

[0023] The phrase one embodiment or some embodiments described in the application means that the specific features, structures or characteristics described in the embodiment are included in one or more embodiments of the application. Therefore, the phrases appearing in different places in the application in one embodiment, in some embodiments, in other embodiments, in additional embodiments, etc. do not necessarily refer to the same embodiment, but mean one or more but not all embodiments, unless otherwise specifically emphasized.

[0024] The technical solutions in the embodiments of the application will be described clearly and completely in combination with the drawings in the embodiments of the application. Obviously, the described embodiments are only some of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0025] Please refer to Figure 1 and Figure 2 The flow chart of the shift control method in a specific embodiment is shown, and the method comprises: S101: Real-time collection of VCU required torque, required gear, speed ratio information, vehicle speed and motor torque.

[0026] In some embodiments, the parameters collected in real time are obtained from a power demand signal sent by a vehicle control unit (VCU) after filtering processing. The gear position is collected by a gear position sensor installed on the gearbox. The speed ratio information includes the speed ratios of each gear of the gearbox and the reducer, which are pre-stored in the memory of the vehicle control system and retrieved by the current gear index. The vehicle speed is obtained by converting the wheel speed signal collected by the wheel speed sensor. The motor torque is obtained from the real-time output torque signal fed back by the motor controller (MCU).

[0027] S102: Estimate the wheel end torque T0 required for the current driving of the vehicle according to the VCU demand torque, demand gear, speed ratio information, vehicle speed, and motor torque collected.

[0028] As an implementation of step S102, the following steps are included: S1021: Extract the VCU demand torque, current motor torque, gearbox speed ratio corresponding to the current gear, reducer speed ratio, and vehicle speed parameters; S1022: Multiply the gearbox speed ratio of the current gear with the reducer speed ratio to obtain the total speed ratio of the current transmission system; S1023: Obtain the transmission system efficiency parameter under the current working condition according to the current gear, vehicle speed, and pre-set transmission efficiency mapping table; S1024: Multiply the current motor torque with the total speed ratio, and then multiply it by the transmission system efficiency parameter to obtain the preliminary wheel end torque; S1025: Correct the preliminary wheel end torque according to the deviation between the VCU demand torque and the preliminary wheel end torque to obtain the wheel end torque T0 required for the current driving of the vehicle.

[0029] In some embodiments, the VCU demand torque, current motor torque, gearbox speed ratio corresponding to the current gear, and reducer speed ratio are extracted, and the wheel radius is extracted from a pre-set parameter library. The total speed ratio of the current transmission system can be calculated by multiplying the gearbox speed ratio of the current gear with the reducer speed ratio.

[0030] The transmission efficiency can be obtained by querying the pre-set gear-vehicle speed-transmission efficiency mapping table according to the current gear and vehicle speed. If the current vehicle speed or gear is a non-discrete point, the transmission efficiency is determined by linear interpolation.

[0031] In this embodiment, the preliminary wheel end torque can be calculated by multiplying the current motor torque with the total speed ratio, and then multiplying it by the transmission efficiency. When correcting the VCU demand, the theoretical wheel end torque corresponding to the VCU demand torque is calculated.

[0032] Optionally, the theoretical wheel end torque = VCU demand torque x total speed ratio, if the preliminary wheel end torque deviates from the theoretical wheel end torque by more than a preset deviation threshold, the preset deviation threshold of the theoretical wheel end torque is used as a correction coefficient.

[0033] It can be seen that, in combination with the actual output of the motor, the characteristics of the transmission system and the power demand of the whole vehicle, the motor torque is converted into the actual torque required to drive the vehicle at the wheel end: the total speed ratio reflects the amplification of the torque by the transmission system, the transmission efficiency corrects the loss in the transmission process, and the VCU demand torque corrects the estimated result to fit the power demand of the whole vehicle, and finally T0 is obtained, which can reflect the real traction demand of the vehicle in the current driving.

[0034] S103: Estimate the available wheel end torque margin Ta of the vehicle in the current gear according to the current gear, the current motor speed and the current motor torque.

[0035] In some embodiments, the current total speed ratio, transmission efficiency and wheel end torque T0 are extracted, the current motor speed is extracted from S101, and the motor speed-maximum torque mapping table is retrieved from the preset parameter library.

[0036] For the calculation method of calculating the wheel end torque margin Ta, the maximum wheel end torque can be subtracted from T0; range checking is performed: if Ta < 0, such as when the motor torque is abnormal and causes the maximum wheel end torque < T0, it is forced to be 0, otherwise the calculated value is retained. It can be seen that the maximum torque at the current speed is accurately obtained through the motor MAP, avoiding the estimation deviation of the maximum wheel end torque caused by the motor output characteristics; the range check is introduced to ensure that the physical meaning of Ta is reasonable.

[0037] As an implementation of S103, it further includes the following steps: S1031: Obtain the transmission system speed ratio information corresponding to the current gear, the speed ratio being the product of the main box speed ratio and the auxiliary box speed ratio of the current gear; In some embodiments, the speed ratio data includes the product of the main box and auxiliary box speed ratios corresponding to each gear, ensuring that the obtained speed ratio completely matches the current gear.

[0038] S1032: According to the current motor speed, obtain the maximum available motor torque at the current speed from the motor torque-speed characteristic curve or real-time data of the motor controller; In some embodiments, the motor torque-speed characteristic curve is a inherent parameter of the motor and is stored in the memory; it is ensured that the real-time maximum torque at the current speed is obtained.

[0039] S1033: Obtain the pre-calibrated total efficiency of the transmission system; In some embodiments, the total efficiency of the transmission system ηCalibration by bench test, is a fixed value or a parameter that changes slightly with working conditions, to ensure that the calculation fits the actual transmission loss.

[0040] S1034: Calculate the maximum wheel end torque that the motor can provide at the current gear, multiply the current motor maximum available torque by the current gear ratio, and then multiply by the total efficiency of the transmission system; In some embodiments, the motor torque needs to be amplified by the gear ratio to the wheel end, and then multiplied by the efficiency to compensate for the transmission loss to obtain the actual available torque at the wheel end.

[0041] S1035: Obtain the wheel end torque T0 required for current driving estimated in step S102, subtract T0 from the maximum wheel end torque obtained in S1034 to obtain the available wheel end torque margin Ta at the current gear.

[0042] In some embodiments, the maximum wheel end torque provided by the motor is subtracted from the current wheel end torque T0 required for driving to obtain the available margin Ta, that is, the torque reserve of the motor can be used for upshift or acceleration.

[0043] As can be seen, Ta is the wheel end embodiment of the motor torque reserve at the current gear, which is the maximum wheel end torque that the motor can provide, minus the wheel end torque that the vehicle must consume for driving, and the remaining torque is the additional output torque of the motor. The greater Ta is, the more torque redundancy the motor has, and the more capable it is to cope with the torque demand after upshift; the smaller Ta is, the closer the motor torque at the current gear is to the limit, and the gear needs to be downshifted to obtain a larger torque reserve.

[0044] S104: Estimate the motor speed at the target gear at the current vehicle speed, the maximum torque available at the target gear motor speed, and then calculate the available wheel end torque margin Tb at the target gear.

[0045] In some embodiments, the target gear is determined, and the target gear ratio, reducer ratio, and wheel radius are extracted from the preset parameter library. This embodiment calculates the target gear total ratio, and then calculates the target gear motor speed: first convert the wheel end speed from the current vehicle speed, then multiply by the target total ratio to obtain the target motor speed. Query the maximum motor torque at the target speed, and find the maximum torque in the motor MAP graph. Finally, calculate the target gear torque margin Tb, here Tb is obtained by subtracting T0 from the target maximum wheel end torque, if Tb < 0, set it to 0.

[0046] It can be seen that the target gear power redundancy pre-judgment link is based on the current vehicle speed to back-propagate the motor speed under the target gear, and then combines the motor output characteristic, the target gear transmission characteristic, estimates the maximum wheel end torque that the target gear can provide, and compares it with the actual demand T0 to obtain Tb: Tb≥target gear minimum redundancy c, which indicates that the target gear can meet the power demand. Tb<c indicates that the target gear is insufficient in power, and the current gear needs to be maintained. In this way, the power feasibility of the target gear is verified in advance, and the reliability of the gear up action is improved.

[0047] In an embodiment of the present application, based on step S104, a possible embodiment will be given below to specifically and non-limitingly illustrate the specific implementation thereof.

[0048] Step S1041: Collect the current vehicle speed pulse signal through the vehicle speed sensor interface circuit, and obtain the digital vehicle speed value after signal conditioning and analog-to-digital conversion.

[0049] Step S1042: According to the current gear state and the preset gear shifting rule, determine the target gear value from the gear shifting strategy table.

[0050] In some embodiments, the gear shifting strategy table is stored in the memory, and the table structure is a multi-dimensional array, the index includes the vehicle speed, the current gear and the driving mode; the multi-condition joint query is used when looking up the table, and the interpolation method is used to improve the continuity. In this way, based on the preset gear shifting rule, the optimal target gear is determined according to the current operating state.

[0051] Step S1043: Take the target gear value as the index to read the corresponding target gear total speed ratio parameter from the memory.

[0052] In some embodiments, the target gear total speed ratio parameter is stored in the parameter table, and corresponds to the target gear one by one; it is read directly by indexing the target gear value; the parameter is pre-calibrated based on the transmission ratio of the gearbox. By querying the transmission system parameters, the total transmission ratio of the target gear is obtained.

[0053] Step S1044: Input the current vehicle speed value and the target gear total speed ratio into the vehicle controller to calculate the theoretical value of the motor speed under the target gear.

[0054] In some embodiments, the multiplication and division operation is performed in the vehicle controller, and the 32-bit floating point number is used to ensure the accuracy; the wheel radius is a preset constant; the calculation process includes unit conversion to ensure dimensional consistency.

[0055] Step S1045: Take the calculated theoretical value of the target gear motor speed as the index to query the motor external characteristic MAP table to obtain the corresponding maximum torque, combine the target gear total speed ratio to calculate the theoretical maximum wheel end torque, and then perform subtraction operation with the required wheel end torque T0 to obtain the available wheel end torque margin Tb under the target gear.

[0056] In some embodiments, the maximum torque is obtained by querying the motor MAP table with the target motor speed; the theoretical maximum wheel end torque is calculated; a subtraction operation is performed with T0 to obtain Tb; and the result is stored in the memory. In this way, the power performance after shifting is evaluated by simulating the performance under the target gear.

[0057] S105: Determine whether the wheel end torque margin Ta is greater than or equal to the current gear upshift torque margin setting value a0. If yes, execute step S106; if no, execute step S107.

[0058] In some embodiments, Ta of the current gear is extracted, and a0 corresponding to the current gear is called from the gear-upshift setting value mapping table in the preset parameter library.

[0059] The a0 of the present embodiment needs to be checked to confirm that its storage path is consistent with the current gear, so as to avoid calling a0 of other gears. After the check is passed, numerical comparison is performed. The ALU (Arithmetic Logic Unit) built-in the controller performs hardware-level comparison to compare Ta and a0 as 32-bit integers. According to the comparison result, an upshift judgment process trigger signal is generated. Finally, the signal is transmitted to the signal receiving end through the CAN bus, and after receiving, a confirmation reply is returned. If no reply is received, the signal is retransmitted until successful reception.

[0060] As can be seen, the preliminary screening link of the shift direction is to compare the power redundancy Ta of the current gear with the minimum redundancy a0 required for upshift, to determine whether the current gear has the basic condition for upshift: Ta≥a0 indicates that the power redundancy of the current gear is sufficient, and the target gear can still meet the demand even if upshifted. Ta<a0 indicates that the power redundancy of the current gear is insufficient, and it needs to be determined whether to downshift to obtain more power, so the downshift judgment process is triggered.

[0061] As a specific implementation of step S105, the following is the specific implementation process: S1051: Extract the wheel end torque margin Ta of the current gear from the calculation result storage area of step S103, and call the upshift torque margin setting value a0 corresponding to the current gear from the preset parameter library of the vehicle control system; In some embodiments, the wheel end torque margin Ta is extracted from the memory. The upshift torque margin setting value a0 is stored in the gear-upshift setting value mapping table, and the current gear identifier collected by step S101 is used as an index query to ensure that a0 corresponds to the current gear uniquely.

[0062] S1052: Perform parameter validity check on the extracted wheel end torque margin Ta and upshift torque margin setting value a0, check whether Ta is within the range of 0 to the maximum wheel end torque margin of the vehicle, and confirm that a0 matches the identifier information of the current gear; In some embodiments, the effective range of Ta is 0≤Ta≤Tmax, Tmax is the maximum wheel end torque margin of the vehicle, and a value outside the range is determined to be invalid and the Ta value of the previous cycle is called.

[0063] The check of a0 is performed by comparing the gear position in the storage path with the current gear position. For example, if the storage path is parameter library / shift up setting value / 3 gear, it needs to match the current gear position 3 gear. If there is no match, the parameter is reloaded.

[0064] S1053: The wheel end torque margin Ta is compared with the shift up torque margin setting value a0 by the comparison logic unit of the vehicle controller. In some embodiments, the comparison logic unit is an arithmetic logic unit (ALU) built in the vehicle controller, and the comparison process is performed in the form of digital signals. Ta and a0 are both converted into 32-bit integers to improve accuracy and ensure real-time performance.

[0065] S1054: According to the comparison result, a corresponding process trigger signal is generated. If Ta is greater than or equal to a0, a shift up judgment process trigger signal is generated. If Ta is less than a0, a shift down judgment process trigger signal is generated.

[0066] In some embodiments, the trigger signal is a binary digital signal. 1 represents the shift up judgment process trigger signal, corresponding to Ta≥a0. 0 represents the shift down judgment process trigger signal, corresponding to Ta

[0067] In this embodiment, the actual power redundancy Ta of the current gear position is compared with the preset minimum redundancy a0 required for shift up, to determine whether the current gear position has the basic condition for shift up. When Ta≥a0, it means that the power redundancy of the current gear position is sufficient, and the target gear position can be further determined to meet the shift up requirement. When Ta

[0068] S106: Determine whether the wheel end torque margin Tb is greater than or equal to the target gear position torque margin setting value c. If yes, control the vehicle to shift up. If no, control the vehicle to keep the current gear position.

[0069] In some embodiments, the Tb of the target gear is extracted, the c corresponding to the target gear is called from the target gear-set value mapping table in the preset parameter library, parameter validity check is performed, the effective range of Tb is 0-target gear maximum wheel end torque margin, and the c check needs to confirm that the storage path is consistent with the target gear, and then the check is passed. Tb and c are compared through the ALU, the result is Tb≥c, and a control signal is generated. Here, the upshift control signal is generated according to the comparison result.

[0070] Optionally, the upshift control signal is a PWM signal, the pulse width is 500 ms, the duty cycle is 50%, and a CRC check code is provided. The signal is transmitted to the control end of the gear shifting actuator through the LIN bus, the gear shifting motor drives the gear shifting fork to move after receiving the signal, the actuator returns the upshift completion feedback signal after completing the action, and the controller confirms the completion of the upshift action after receiving the feedback. Ensure that the gear shifting actuator moves smoothly and improve the reliability of the upshift action.

[0071] As a specific implementation of step S106, the following is a specific implementation process: Step S1061: reading the value of the target gear wheel end torque margin Tb calculated in step S104 from the memory.

[0072] In some embodiments, the Tb value is stored in the memory, and the read value is reasonably checked, including range verification and change rate monitoring. Ensure the accuracy and timeliness of the decision data to provide reliable input for upshift feasibility judgment.

[0073] Step S1062: reading the corresponding c value from the target gear torque margin set value mapping table stored in the memory with the target gear value as the index.

[0074] In some embodiments, the target gear torque margin set value mapping table is stored in the memory, the table structure includes the target gear index and the corresponding c value; direct address mapping is used when looking up the table to quickly obtain the parameters; the c value is pre-calibrated based on the acceleration performance requirement after gear shifting to ensure power continuity.

[0075] Step S1063: inputting the Tb value and the c value into the vehicle controller and performing a greater-than-or-equal-to comparison operation.

[0076] Step S1064: generating a control decision signal according to the comparison result, generating an upshift control instruction if Tb≥c, or generating a gear position maintenance control instruction.

[0077] In some embodiments, the corresponding control instruction is generated in the vehicle controller according to the comparison result flag; the instruction code uses a standard format and contains operation type and parameter information; the generation process considers system safety constraints to ensure the rationality of the instruction.

[0078] Step S1065: transmit the control instruction to the shift actuator controller to drive the corresponding electromagnetic valve or motor to perform the upshift or hold action.

[0079] In some embodiments, the control instruction is transmitted through the CAN bus; the instruction message contains the target gear, the operation type and the timestamp; after receiving the instruction, the actuator controller drives the electromagnetic valve or servo motor to perform the corresponding action; the transmission process has a response mechanism to ensure correct execution of the instruction and accurate gear shifting.

[0080] S107: Determine whether the wheel end torque margin Ta is less than the current gear downshift torque margin set value b0. If yes, control the vehicle to downshift; if no, control the vehicle to maintain the current gear.

[0081] In some embodiments, the Ta of the current gear is extracted, and the b0 corresponding to the current gear is retrieved from the gear-downshift set value mapping table in the preset parameter library.

[0082] Then perform parameter validity check, and perform numerical comparison after passing the check. Compare Ta and b0 through ALU, the result is Ta < b0; generate control signal. According to the comparison result, generate downshift control signal. Transmit the signal to the shift actuator through the LIN bus, the actuator drives the shift fork to move, and returns the downshift completion feedback signal after completion; if Ta ≥ b0, generate the control signal to maintain the current gear, and the actuator does not act, maintaining the current gear.

[0083] Based on the determination that the current gear does not meet the upshift condition in S105, the embodiment determines whether the power redundancy Ta of the current gear is lower than the downshift threshold b0. Ta < b0 indicates that the power redundancy of the current gear is insufficient to meet the T0 demand, such as insufficient power when climbing. Therefore, downshift is performed; Ta ≥ b0 indicates that the power redundancy of the current gear is sufficient, and there is no need to downshift, so the current gear is maintained to ensure sufficient power for the vehicle to travel.

[0084] S108: After completing the upshift or downshift, determine whether the wheel end torque margin Ta meets b0 < Ta < a0. If yes, control the shift to end.

[0085] In some embodiments, after the upshift or downshift is completed, based on the overall speed ratio of the new current gear, the current motor speed and the new transmission efficiency, the calculation process of S103 is re-executed to obtain a new Ta.

[0086] The embodiment also retrieves b0 and a0 of the new current gear from the preset parameter library, confirms that b0 < a0, and the new Ta is within the maximum wheel end torque margin range of 0-4 gears, b0 and a0 are matched with the new gear, and the verification is passed. Then, the new Ta > b0 is compared, the result is true; the new Ta < a0 is compared, the result is true; the comprehensive result is that both are satisfied, and the gear shifting end control signal is generated; finally, the signal is transmitted to the gear shifting control main unit through the CAN bus, the main unit receives and terminates the current gear shifting process after receiving, and the vehicle enters a stable driving state.

[0087] The embodiment re-estimates the Ta of the new gear to avoid using the old gear parameter to judge the state of the new gear. The reasonable setting of the redundant interval ensures that the power of the new gear is neither excessive nor insufficient, improves the driving economy and power, ensures that the vehicle is always in the optimal gear, and improves the driving experience.

[0088] In an embodiment of the present application, based on step S108, a possible embodiment will be given below to illustrate the specific implementation thereof. S108 specifically includes the following steps: S1081: After the upshift or downshift action is completed, the wheel end torque margin Ta under the new current gear is re-estimated, and the downshift torque margin setting value b0 and the upshift torque margin setting value a0 corresponding to the new current gear are retrieved from the memory.

[0089] In some embodiments, re-estimating the Ta of the new current gear is to re-execute the calculation process of S103 based on the total speed ratio of the new gear and the current motor speed after the gear shifting action is completed, to ensure that Ta is the real-time power redundancy value under the new gear. b0 and a0 are retrieved from the gear-up / down gear setting value mapping table, the mapping table is classified according to the gear number, and the identification of the new current gear after gear shifting is used as an index to ensure that the setting values correspond to the new gear.

[0090] S1082: The re-acquired wheel end torque margin Ta, downshift setting value b0 and upshift setting value a0 are subjected to parameter validity verification, it is checked whether Ta is within the range of 0 to the maximum wheel end torque margin of the new current gear, and it is confirmed that b0 is less than a0 and both are matched with the identification information of the new current gear.

[0091] In some embodiments, the parameter validity verification includes the following contents: First, the range verification of Ta, 0 < Ta < the maximum wheel end torque margin of the new current gear, and if it is exceeded, the last period estimation value is taken.

[0092] Second, the logic verification of b0 and a0, to confirm that b0 < a0, to avoid the invalidation of the interval caused by the reversal of the setting values.

[0093] Third, the gear position matching verification, comparing the gear position in the storage path of b0, a0 with the new current gear position, if the parameter library / gear setting value / 3 gear needs to match with the new current gear position 3 gear, verifying failure to reload the parameters.

[0094] S1083: judging whether the wheel end torque margin Ta is greater than the downshift setting value b0, and whether Ta is less than the upshift setting value a0 through the vehicle controller; In some embodiments, the hardware level comparison is performed twice: the first comparison is to determine whether Ta is higher than the lower limit of the downshift, and the second comparison is to determine whether Ta is lower than the upper limit of the upshift. This ensures the real-time performance of the comprehensive result and avoids the influence of speed fluctuation caused by time difference.

[0095] S1084: generating a control signal according to the comprehensive result of the two judgments, if Ta is greater than b0 and less than a0 at the same time, generating a shift end control signal, if not, generating a continue monitoring control signal; In some embodiments, the control signal is a digital level signal, the shift end control signal is a high level, and the continue monitoring control signal is a low level. A time stamp is added when the signal is generated to ensure synchronization with the state update of the new current gear position.

[0096] S1085: transmitting the generated control signal through the vehicle control main bus, if it is a shift end signal, terminating the shift process, if it is a continue monitoring signal, triggering the next round of wheel end torque margin acquisition and judgment.

[0097] The steps of the embodiment change the transmission ratio and the motor speed adaptation relationship after upshift or downshift, and the original power redundancy Ta is no longer applicable to the new gear position. By re-estimating Ta of the new current gear position and comparing it with the reasonable redundancy interval preset for the gear position, if Ta is within the interval, it means that the power redundancy of the new gear position can meet the driving demand and has no excessive redundancy, the shift target is achieved, and the process can be terminated. If Ta is not within the interval, continue monitoring to determine whether secondary shift is needed to ensure that the power redundancy of the final gear position is always in the optimal state.

[0098] It should be understood that the size of the serial number of each step in the above embodiment does not mean the order of execution, the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0099] The following is an embodiment of the shift control system provided by the embodiment of the present disclosure. The system and the shift control method of each embodiment described above belong to the same inventive concept. The details not described in the embodiment of the shift control system can be referred to the embodiment of the shift control method described above.

[0100] AsFigure 3 As shown, the system includes: An information acquisition module 201, configured to collect in real time the VCU required torque, required gear position, speed ratio information, vehicle speed, and motor torque; A torque estimation module 202, configured to estimate the wheel-end torque T0 required for the vehicle to travel currently according to the collected VCU required torque, required gear position, speed ratio information, vehicle speed, and motor torque; A gear position margin estimation module 203, configured to estimate the available wheel-end torque margin Ta of the vehicle in the current gear position according to the current gear position, current motor speed, and current motor torque at the current vehicle speed; A gear position availability estimation module 204, configured to estimate the motor speed of the target gear position and the maximum available torque at the motor speed of the target gear position at the current vehicle speed, and then calculate the available wheel-end torque margin Tb of the vehicle in the target gear position; An upshift judgment module 205, configured to judge whether the wheel-end torque margin Ta is greater than or equal to the upshift torque margin set value a0 of the current gear position. If so, execute the upshift execution module; if not, execute the downshift execution module; An upshift execution module 206, configured to judge whether the wheel-end torque margin Tb is greater than or equal to the torque margin set value c of the target gear position. If so, control the vehicle to upshift; if not, control the vehicle to maintain the current gear position; A downshift execution module 207, configured to judge whether the wheel-end torque margin Ta is less than the downshift torque margin set value b0 of the current gear position. If so, control the vehicle to downshift; if not, control the vehicle to maintain the current gear position; A shift judgment module 208, configured to judge whether the wheel-end torque margin Ta satisfies b0 < Ta < a0 after the upshift or downshift is completed. If so, control the shift to end.

[0101] As Figure 4 shown, the present application further provides an electronic device, including a display module 103, a memory 102, a processor 101, a communication module 104, and a computer program stored on the memory and executable on the processor 101. When the processor 101 executes the program, the steps of the shift control method are implemented.

[0102] In the embodiments of the present invention, the electronic device includes, but is not limited to, a laptop computer, a desktop computer, a workbench, a personal digital assistant, a server, a blade server, a mainframe computer, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, a personal digital processor, a cellular phone, a smart phone, a wearable device, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the embodiments of the present application described herein and / or claimed.

[0103] In embodiments of the present application, the processor 101 can be implemented by using at least one of an application-specific integrated circuit, a programmable logic device, a field programmable gate array, a processor, a controller, a microcontroller, a vehicle controller, an electronic unit designed to perform the functions described herein, and in some cases, such implementation can be implemented in a controller. For software implementation, the implementation of such as a process or a function can be implemented with a separate software module that allows at least one function or operation to be performed. The software code can be implemented by a software application (or program) written in any appropriate programming language, which can be stored in a memory and executed by a controller.

[0104] The display module 103 is used to display information input by a user or information provided to a user. The display module 103 can include a display panel, which can be configured in the form of a liquid crystal display, an organic light emitting diode, etc.

[0105] The memory 102 can be used to store software programs as well as various data. The memory 102 can include a high-speed random access memory, and can also include a non-volatile memory such as at least one magnetic disk storage device, a flash memory device, or other volatile solid-state memory device.

[0106] The communication module 104 transmits and / or receives radio signals to and / or from at least one of a base station, an external terminal, and a server. Such radio signals can include voice call signals, video call signals, or various types of data according to text and / or multimedia message transmission and reception.

[0107] The present application also provides a storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the shift control method.

[0108] The storage medium can take any combination of one or more of a readable medium. The readable medium can be a readable signal medium or a readable storage medium. The readable storage medium, for example, can be, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or apparatus, or any combination of the above. More specific examples (non-exhaustive list) of the readable storage medium include an electrical connection having one or more wires, a portable disc, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above.

[0109] In a storage medium, a program product capable of implementing the method described in the specification is stored. In some possible implementation manners, various aspects of the disclosure can also be implemented in the form of a program product, which includes program codes for causing terminal equipment to perform the steps according to various exemplary embodiments of the disclosure described in the exemplary method part of the specification when the program product runs on the terminal equipment.

[0110] The above description of disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A shift control method characterized by the method Comprising: S101: real-time acquisition of VCU demand torque, demand gear position, speed ratio information, vehicle speed and motor torque; S102: according to the VCU demand torque, demand gear position, speed ratio information, vehicle speed and motor torque collected, estimate the wheel end torque T0 required for the current driving of the vehicle; S103: according to the current gear position under the current vehicle speed, the current motor speed, the current motor torque, estimate the available wheel end torque margin Ta of the vehicle under the current gear position; S104: estimate the motor speed of the target gear position under the current vehicle speed, the maximum available torque under the motor speed of the target gear position, and then calculate the available wheel end torque margin Tb of the vehicle under the target gear position; S105: determine whether the wheel end torque margin Ta is greater than or equal to the current gear position upshift torque margin setting value a0, if yes, execute step S106, if not, execute step S107; S106: determine whether the wheel end torque margin Tb is greater than or equal to the target gear position torque margin setting value c, if yes, control the vehicle to upshift, if not, control the vehicle to keep the current gear position; S107: determine whether the wheel end torque margin Ta is less than the current gear position downshift torque margin setting value b0, if yes, control the vehicle to downshift, if not, control the vehicle to keep the current gear position; S108: after completing upshift or downshift, determine whether the wheel end torque margin Ta satisfies b0 2. The shift control method according to claim 1, wherein S102 specifically comprises the following steps: extracting VCU demand torque, current motor torque, transmission gear ratio corresponding to the current gear position, reducer gear ratio and vehicle speed parameters; multiply the transmission gear ratio of the current gear position with the reducer gear ratio to obtain the total gear ratio of the current transmission system; obtain the transmission system efficiency parameter under the current working condition according to the current gear position, vehicle speed and pre-set transmission efficiency mapping table; multiply the current motor torque with the total gear ratio, and then multiply it by the transmission system efficiency parameter to obtain the preliminary wheel end torque; correct the preliminary wheel end torque according to the deviation between the VCU demand torque and the preliminary wheel end torque to obtain the wheel end torque T0 required for the current driving of the vehicle.

3. The shift control method according to claim 1, wherein S103 specifically comprises the following steps: obtain the transmission system gear ratio information corresponding to the current gear position, and the gear ratio is the product of the main box gear ratio and the auxiliary box gear ratio of the current gear position; obtain the maximum available motor torque under the current speed from the motor torque-speed characteristic curve or the real-time data of the motor controller; obtain the pre-calibrated total efficiency of the transmission system; calculate the maximum wheel end torque that the motor can provide under the current gear position, multiply the current maximum available motor torque by the current gear ratio, and then multiply it by the total efficiency of the transmission system; obtain the wheel end torque T0 required for the current driving estimated in step S102, subtract T0 from the obtained maximum wheel end torque to obtain the available wheel end torque margin Ta of the vehicle under the current gear position.

4. The shift control method according to claim 1, wherein S104 specifically comprises the following steps: ​ ​ ​ The current vehicle speed pulse signal is collected through the vehicle speed sensor interface circuit, and a digital vehicle speed value is obtained after signal conditioning and analog-to-digital conversion; According to the current gear state and the preset gear shifting rule, a target gear value is determined from a gear shifting strategy table; The target gear value is taken as an index to read a corresponding target gear total speed ratio parameter from the memory; The current vehicle speed value and the target gear total speed ratio are input into a vehicle controller to calculate a theoretical motor speed value under the target gear; The calculated target gear motor speed theoretical value is taken as an index to query a motor external characteristic MAP table to obtain a corresponding maximum torque, and the target gear total speed ratio is combined to calculate a theoretical maximum wheel end torque, which is then subjected to subtraction operation with a required wheel end torque T0 to obtain a vehicle available wheel end torque margin Tb under the target gear.

5. The gear shifting control method according to claim 1, characterized in that, S105 specifically comprises the following steps: The wheel end torque margin Ta of the current gear is extracted from the calculation result storage area of step S103, and the upshift torque margin setting value a0 corresponding to the current gear is called from the preset parameter library of the vehicle control system; The extracted wheel end torque margin Ta and the upshift torque margin setting value a0 are subjected to parameter validity check, it is checked whether Ta is within the range of 0 to the maximum wheel end torque margin of the vehicle, and it is confirmed that a0 matches the identification information of the current gear; The wheel end torque margin Ta and the upshift torque margin setting value a0 are subjected to numerical value comparison through the comparison logic unit of the vehicle controller; According to the comparison result, a corresponding flow trigger signal is generated, if Ta is greater than or equal to a0, an upshift judgment flow trigger signal is generated, and if Ta is less than a0, a downshift judgment flow trigger signal is generated.

6. The gear shifting control method according to claim 1, characterized in that, S106 specifically comprises the following steps: The numerical value of the target gear wheel end torque margin Tb calculated in step S104 is read from the memory; The target gear value is taken as an index to read a corresponding c value from the target gear torque margin setting value mapping table stored in the memory; The Tb value and the c value are input into the vehicle controller to perform greater than or equal comparison operation; According to the comparison result, a control decision signal is generated, if Tb is greater than or equal to c, an upshift control instruction is generated, otherwise a gear holding control instruction is generated; The control instruction is transmitted to the gear shifting actuator controller to drive the corresponding electromagnetic valve or motor to perform upshift or holding action.

7. The gear shifting control method according to claim 1, characterized in that, S108 specifically comprises the following steps: After the upshift or downshift action is completed, the wheel end torque margin Ta under the new current gear is re-estimated, and the downshift torque margin setting value b0 and the upshift torque margin setting value a0 corresponding to the new current gear are called from the memory; S1082: The re-acquired wheel end torque margin Ta, the downshift setting value b0 and the upshift setting value a0 are subjected to parameter validity check, it is checked whether Ta is within the range of 0 to the maximum wheel end torque margin of the new current gear, and it is confirmed that b0 is less than a0 and both match the identification information of the new current gear. S1083: Determine whether the wheel end torque margin Ta is greater than the downshift setting value b0, and then determine whether Ta is less than the upshift setting value a0 through the vehicle controller; S1084: Generate a control signal according to the comprehensive results of the two determinations, generate a shift end control signal if Ta is greater than b0 and less than a0 at the same time, and generate a continue monitoring control signal if the conditions are not met at the same time; S1085: Transmit the generated control signal through the vehicle control main bus, terminate the shift process if it is a shift end signal, and trigger the next round of wheel end torque margin collection and determination if it is a continue monitoring signal.

8. A shift control system characterized by comprising: The system is used to implement the shift control method of claim 1; the system comprises: An information collection module for collecting VCU demand torque, demand gear position, speed ratio information, vehicle speed, and motor torque in real time; A torque estimation module for estimating the wheel end torque T0 required for the current vehicle to travel according to the collected VCU demand torque, demand gear position, speed ratio information, vehicle speed, and motor torque; A gear position margin estimation module for estimating the available wheel end torque margin Ta of the vehicle under the current gear position, current motor speed, and current motor torque at the current vehicle speed; A gear position available estimation module for estimating the motor speed of the target gear position, the maximum torque available at the target gear position motor speed, and then calculating the available wheel end torque margin Tb of the vehicle under the target gear position; An upshift judgment module for determining whether the wheel end torque margin Ta is greater than or equal to the current gear position upshift torque margin setting value a0, executing the upshift execution module if yes, and executing the downshift execution module if no; An upshift execution module for determining whether the wheel end torque margin Tb is greater than or equal to the target gear position torque margin setting value c, controlling the vehicle to upshift if yes, and controlling the vehicle to maintain the current gear position if no; A downshift execution module for determining whether the wheel end torque margin Ta is less than the current gear position downshift torque margin setting value b0, controlling the vehicle to downshift if yes, and controlling the vehicle to maintain the current gear position if no; A shift determination module for determining whether the wheel end torque margin Ta satisfies b0 < Ta < a0 after completing upshift or downshift, and controlling the shift to end if yes.

9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and executable on the processor, characterized in that, The processor executes the program to implement the steps of the shift control method of any one of claims 1 to 7.

10. A storage medium having stored thereon a computer program, characterized in that The computer program is executed by the processor to implement the steps of the shift control method of any one of claims 1 to 7.

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