New energy commercial vehicle gear shifting braking neutral gear returning control method and new energy vehicle

Abstract

The invention discloses a new energy commercial vehicle gear shifting braking neutral gear returning control method and a new energy vehicle, and belongs to the technical field of new energy heavy truck gear shifting control. The control method comprises the following steps: acquiring a brake pedal opening signal for representing the braking operation of a driver and a gear shifting mechanism position sensor voltage signal for representing the gear shifting operation of the driver in the driving process; and the brake pedal opening signal and the gear shifting mechanism sensor voltage signal are compared with set thresholds respectively, a driver intention judgment signal is generated, and then a corresponding vehicle control instruction is generated. According to the method, the braking intention of a driver in the gear shifting process can be accurately recognized, an accurate decision is made, smoothness and efficiency in the gear shifting process are guaranteed, meanwhile, driving safety is guaranteed, mechanical abrasion can be reduced, and certain application value is achieved.

Description

Technical Field

[0001] This invention relates to a method for controlling the shifting and braking return to neutral in a new energy commercial vehicle and to the new energy vehicle itself, belonging to the field of shifting control technology for new energy heavy trucks. Background Technology

[0002] During vehicle operation, different strategies exist in the industry for handling braking during gear shifts. One approach involves the transmission controller forcibly reverting to neutral if a braking signal is detected during a gear shift. This method disrupts driving expectations and poses safety risks. If the driver applies the brakes while shifting gears, the transmission reverting to neutral can cause an unexpected interruption of vehicle power, potentially leading to vehicle roll and accelerated mechanical wear. Furthermore, the entire gear shifting action is aborted and reset, requiring the driver to restart the process when requesting a shift again, thus increasing the overall system response time.

[0003] Another approach is to completely ignore the brake signal and only respond to the braking request after the gear shift is complete. This method goes against the driver's intention. In any situation, pressing the brake pedal is the driver's most direct and highest priority expression of braking intention. Ignoring the brake signal poses a significant safety hazard. Summary of the Invention

[0004] The purpose of this invention is to provide a method for controlling the shifting and braking of a new energy commercial vehicle to return to neutral, and a new energy vehicle. By collecting signals representing the driver's intention and performing logical judgment with a set threshold, the method accurately identifies the driver's braking intention during the shifting process and makes precise decisions, ensuring the smoothness and efficiency of the shifting process, while also ensuring driving safety and reducing mechanical wear, thus having certain application value.

[0005] To achieve the above objectives, the present invention is implemented using the following technical solution.

[0006] On one hand, the present invention provides a method for controlling the shifting and braking return to neutral in a new energy commercial vehicle, comprising:

[0007] The system collects brake pedal opening signals, which characterize the driver's braking operation, and voltage signals from the shift mechanism position sensor, which characterize the driver's shifting operation.

[0008] The brake pedal opening signal and the shift mechanism sensor voltage signal are compared with their respective set thresholds to generate a driver intention judgment signal, and then generate the corresponding vehicle control command.

[0009] Optionally, the basic conditions for performing the method include:

[0010] The current gear is forward and the vehicle speed is greater than the set threshold V1. The vehicle has not received a shift command from the driver to exit forward gear.

[0011] Optionally, when the gear shift process is in the speed synchronization phase:

[0012] If the brake pedal opening is less than the set threshold B1, the shifting mechanism continues to execute the shifting process.

[0013] If the brake pedal opening is greater than the set threshold B2, the gear shifting mechanism interrupts the speed synchronization process and returns to neutral.

[0014] Optionally, when the gear shift process is in the speed synchronization stage and the brake pedal opening range is (B1, B2), the target speed value N2 is calculated based on the current speed value N1.

[0015] If the difference between the target speed value N2 and the current speed value N1 is greater than the set threshold N3, and the duration is greater than the set threshold T1, the shift mechanism interrupts the speed synchronization process and returns to neutral.

[0016] Optionally, when the gear shifting process is in the upshift phase and the brake pedal opening is greater than the set threshold B1;

[0017] Between adjacent low and high gears, the voltage value U2 of the shift mechanism position sensor ranges from -U1 to U1.

[0018] Optionally, when the gear shifting process is in the gear engagement phase, and the difference between the voltage value U2 of the gear shifting mechanism position sensor and the voltage value U3 of the gear shifting mechanism position sensor when in neutral is within (-U1, U1), the gear shifting mechanism returns to neutral.

[0019] When the difference between the voltage value U2 of the shift mechanism position sensor and the voltage value U3 of the shift mechanism position sensor in neutral position is not within (-U1, U1), the shift mechanism continues to execute the shifting process.

[0020] Optionally, when the gear shifting process is in the upshift phase and the change in the voltage value U2 of the gear shifting mechanism position sensor within the set time threshold T2 is less than the set threshold U4, the gear shifting mechanism returns to neutral.

[0021] Optionally, when the gear shifting process is in the upshifting phase and the voltage value U2 of the gear shifting mechanism position sensor is in the neutral position within the set time threshold T3, the gear shifting mechanism returns to neutral within the set error range of the voltage value U3 of the gear shifting mechanism position sensor.

[0022] If the voltage value U2 of the shift mechanism position sensor is not in the neutral position within the set time threshold T3, and the error range of the voltage value U3 of the shift mechanism position sensor is within the set time threshold T3, the shift mechanism fails to return to neutral, and the vehicle issues a fault alarm.

[0023] Optionally, the control method is executed by a vehicle control system, which includes a vehicle control unit (VCU), a transmission control unit (TCU), and a motor control unit (MCU), wherein the VCU, TCU, and MCU communicate via a CAN bus.

[0024] The TCU is configured to: control the shift mechanism to adjust the gearbox gear, calculate the target speed for speed synchronization based on the speed of the gearbox output shaft, send the gearbox gear information to the VCU, and send the requested torque or target speed to the MCU;

[0025] The VCU is configured to send vehicle speed and brake pedal opening signals to the TCU.

[0026] The MCU is configured to send the actual torque and speed signals of the motor to the TCU, and receive the requested torque or target speed sent by the TCU to control the drive motor to output the corresponding torque or speed.

[0027] Secondly, the present invention provides a new energy vehicle, comprising:

[0028] Memory, used to store instructions;

[0029] A processor is configured to execute the instructions, causing the new energy vehicle to perform the steps of implementing the new energy commercial vehicle shift braking return to neutral control method as described in any one of the first aspects.

[0030] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0031] This invention, by collecting signals representing the driver's intentions and performing logical judgments against set thresholds, can accurately identify the driver's braking intentions during gear shifting and make precise decisions. Simultaneously, it protects the gearbox gears and their critical mechanical components, ensuring smoothness and efficiency during gear shifting. Prioritizing the identification and execution of the driver's operational intentions and ensuring driving safety, this invention has significant application value. Attached Figure Description

[0032] Figure 1 A schematic diagram of a new energy commercial vehicle shifting and braking return-to-neutral control method provided in an embodiment of the present invention;

[0033] Figure 2 A flowchart of the gear shift control method for speed synchronization provided in an embodiment of the present invention;

[0034] Figure 3 A flowchart of the gear shift control method for the gear engagement stage provided in an embodiment of the present invention;

[0035] Figure 4 This is a schematic diagram of a vehicle control system provided in an embodiment of the present invention. Detailed Implementation

[0036] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations thereof. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0037] The term "and / or" simply describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0038] Example 1

[0039] This embodiment describes a method for controlling the shifting and braking return to neutral in a new energy commercial vehicle, such as... Figure 1 As shown, it includes the following steps:

[0040] The system collects brake pedal opening signals, which characterize the driver's braking operation, and voltage signals from the shift mechanism position sensor, which characterize the driver's shifting operation.

[0041] The brake pedal opening signal and the shift mechanism sensor voltage signal are compared with their respective set thresholds to generate a driver intention judgment signal, and then generate the corresponding vehicle control command.

[0042] The gear shifting process for new energy commercial vehicles includes four stages: disengagement, speed synchronization, gear engagement, and torque return. When disengaging, power is interrupted, and regardless of braking intent, the optimal approach is to allow the system to smoothly complete the disengagement. During torque return, the gears are fully engaged, and the gear shifting action is essentially complete. Applying the brakes is equivalent to braking during normal driving, and the system requires no further processing. Therefore, the main considerations are speed synchronization and gear engagement. The system determines which sub-stage the shift is in by using enumerated values ​​of the gear shifting process.

[0043] When implementing the above-mentioned new energy commercial vehicle shifting and braking return to neutral control method, the basic conditions include: the vehicle is in forward gear during driving, the current vehicle speed is greater than the set threshold V1, the brake pedal opening is greater than the set threshold B1, the vehicle is in the shifting process, and the driver has not manually shifted forward gear to neutral.

[0044] When the gear shifting process is in the speed synchronization stage, such as Figure 2 As shown:

[0045] If the brake pedal opening is less than the set threshold B1 (shallow pressing), the shifting mechanism continues to execute the shifting process;

[0046] If the brake pedal opening is greater than the set threshold B2 (deeply depressed), the gear shifting mechanism interrupts the speed synchronization process, shifts back to neutral, and waits for the gear shifting opportunity.

[0047] When the brake pedal opening is within the range of (B1, B2), the vehicle calculates the target speed value N2 based on the current speed value N1.

[0048] If the difference between the target speed value N2 and the current speed value N1 is greater than the set threshold N3, and the duration is greater than the set threshold T1, the shift mechanism interrupts the speed synchronization process, returns to neutral, and waits for the shift opportunity.

[0049] When the gear shifting process is in the upshift phase, such as Figure 3 As shown:

[0050] When the brake pedal opening is greater than the set threshold B1, this embodiment takes the first and second gear shifting mechanism of the electric drive axle transmission as an example. The first and second gear shifting mechanism rotates counterclockwise to engage first gear and clockwise to engage second gear. When the first and second gear shifting mechanism is in neutral, the shift clearance between the shift fork engagement sleeve and the first and second gear output gears is X1 (electric drive axle design parameter). The voltage value U2 of the position sensor of the first and second gear shifting mechanism changes within the range of (-U1, U1).

[0051] When the difference between the voltage value U2 of the shift mechanism position sensor and the voltage value U3 of the shift mechanism position sensor in neutral position is (-U1, U1), the shift mechanism returns to neutral and waits for the shifting opportunity.

[0052] When the difference between the voltage value U2 of the shift mechanism position sensor and the voltage value U3 of the shift mechanism position sensor in neutral position is not within (-U1, U1), the shift mechanism continues to execute the shifting process.

[0053] When the change in voltage value U2 of the shift mechanism position sensor within a set time threshold T2 is less than the set threshold U4, the first and second gear shift mechanism stalls, and the shift mechanism returns to neutral, waiting for a shift opportunity.

[0054] When the voltage value U2 of the shift mechanism position sensor is in the neutral position within the set time threshold T3, and the shift mechanism returns to neutral within the set error range of the voltage value U3 of the shift mechanism position sensor, the shift mechanism completes the return to neutral.

[0055] The error range of the shift mechanism position sensor voltage U3 when in neutral is related to the shift clearance setting of the axle itself. When the shift clearance X1 between the shift fork engagement sleeve and the first and second gear output gears is 1mm, the error range of U3 is (-100mV, 100mV).

[0056] If the voltage value U2 of the shift mechanism position sensor is not in neutral within the set time threshold T3, and the shift mechanism fails to return to neutral within the set error range of the voltage value U3, the vehicle will issue a fault alarm.

[0057] In this embodiment, in all the above operating conditions, the signal value of the shift mechanism position sensor is always used to determine whether to return to the neutral position.

[0058] The above control method is executed by the vehicle control system, such as Figure 4 As shown, the control system includes a vehicle control unit (VCU), a transmission control unit (TCU), and a motor control unit (MCU), which communicate via a CAN bus.

[0059] The TCU is configured to: control the shift mechanism to adjust the gearbox gear, calculate the target speed for speed synchronization based on the speed of the gearbox output shaft, send the gearbox gear information to the VCU, and send the requested torque or target speed to the MCU;

[0060] The VCU is configured to send vehicle speed and brake pedal opening signals to the TCU.

[0061] The MCU is configured to send the actual torque and speed signals of the motor to the TCU, and receive the requested torque or target speed sent by the TCU to control the drive motor to output the corresponding torque or speed.

[0062] Example 2

[0063] Based on the same inventive concept as Embodiment 1, this embodiment introduces a new energy vehicle, including:

[0064] Memory, used to store instructions;

[0065] A processor is configured to execute the instructions, causing the new energy vehicle to perform the steps of the new energy commercial vehicle shift braking return to neutral control method as described in any one of Embodiment 1.

[0066] In summary, by collecting signals representing the driver's intentions and performing logical judgments against set thresholds, this invention can accurately identify the driver's braking intentions during gear shifting and make precise decisions. Simultaneously, it protects the gearbox gears and their critical mechanical components, ensuring smoothness and efficiency during gear shifting. Prioritizing the identification and execution of the driver's operational intentions and ensuring driving safety, this invention has significant application value.

Claims

1. A method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle, characterized in that, include: The system collects brake pedal opening signals, which characterize the driver's braking operation, and voltage signals from the shift mechanism position sensor, which characterize the driver's shifting operation. The brake pedal opening signal and the shift mechanism sensor voltage signal are compared with their respective set thresholds to generate a driver intention judgment signal, and then generate the corresponding vehicle control command.

2. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 1, characterized in that, The basic conditions for performing the method include: The current gear is forward and the vehicle speed is greater than the set threshold V1. The vehicle has not received a shift command from the driver to exit forward gear.

3. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 2, characterized in that, When the gear shifting process is in the speed synchronization phase: If the brake pedal opening is less than the set threshold B1, the shifting mechanism continues to execute the shifting process. If the brake pedal opening is greater than the set threshold B2, the gear shifting mechanism interrupts the speed synchronization process and returns to neutral.

4. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 3, characterized in that, When the gear shifting process is in the speed synchronization stage and the brake pedal opening range is (B1, B2), the target speed value N2 is calculated based on the current speed value N1. If the difference between the target speed value N2 and the current speed value N1 is greater than the set threshold N3, and the duration is greater than the set threshold T1, the shift mechanism interrupts the speed synchronization process and returns to neutral.

5. The method for controlling the shifting and braking return to neutral of a new energy commercial vehicle according to claim 4, characterized in that, When the gear shifting process is in the upshift phase and the brake pedal opening is greater than the set threshold B1; Between adjacent low and high gears, the voltage value U2 of the shift mechanism position sensor ranges from -U1 to U1.

6. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 5, characterized in that, When the gear shifting process is in the upshift phase, and the difference between the voltage value U2 of the gear shifting mechanism position sensor and the voltage value U3 of the gear shifting mechanism position sensor when in neutral is (-U1, U1), the gear shifting mechanism returns to neutral. When the difference between the voltage value U2 of the shift mechanism position sensor and the voltage value U3 of the shift mechanism position sensor in neutral position is not within (-U1, U1), the shift mechanism continues to execute the shifting process.

7. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 6, characterized in that, When the gear shifting process is in the upshift phase, and the change in the voltage value U2 of the gear shifting mechanism position sensor within the set time threshold T2 is less than the set threshold U4, the gear shifting mechanism returns to neutral.

8. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 7, characterized in that, When the gear shifting process is in the upshifting phase, and the voltage value U2 of the gear shifting mechanism position sensor is in the neutral position within the set time threshold T3, the gear shifting mechanism returns to neutral within the set error range of the voltage value U3 of the gear shifting mechanism position sensor. If the voltage value U2 of the shift mechanism position sensor is not in the neutral position within the set time threshold T3, and the error range of the voltage value U3 of the shift mechanism position sensor is within the set error range, the shift mechanism fails to return to neutral, and the vehicle issues a fault alarm.

9. The method for controlling the shifting, braking, and returning to neutral gear in a new energy commercial vehicle according to claim 8, characterized in that, The control method is executed by the vehicle control system, which includes a vehicle control unit (VCU), a transmission control unit (TCU), and a motor control unit (MCU). The VCU, TCU, and MCU communicate via a CAN bus. The TCU is configured to: control the shift mechanism to adjust the gearbox gear, and calculate the target speed for speed synchronization based on the speed of the gearbox output shaft; Send the gear position information of the transmission to the VCU, and send the requested torque or target speed to the MCU; The VCU is configured to send vehicle speed and brake pedal opening signals to the TCU. The MCU is configured to send the actual torque and speed signals of the motor to the TCU, and receive the requested torque or target speed sent by the TCU to control the drive motor to output the corresponding torque or speed.

10. A new energy vehicle, characterized in that, include: Memory, used to store instructions; A processor is configured to execute the instructions, causing the new energy vehicle to perform the steps of the new energy commercial vehicle shift braking return to neutral control method as described in any one of claims 1-9.

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