Automatic slope parking control method and system for electric automobile, automobile and electronic equipment

Abstract

The invention discloses an automatic slope parking control method and system for an electric vehicle, the vehicle and electronic equipment, and relates to the technical field of electric vehicles. According to the method, after a first state parameter including a gear state and a motor state of a vehicle is obtained, whether the vehicle meets a first preset slope holding condition or not is determined based on the gear state and the motor state, namely, the gear is in a gear switching state and the absolute value of the rotating speed of a motor is increased, or the gear is not in the gear switching state; and determining whether the vehicle meets a second preset slope holding condition based on the first state parameter after determining that the vehicle meets the first preset slope holding condition, and entering a slope holding mode after determining that the vehicle meets the second preset slope holding condition. Therefore, the problems that hardware needs to be additionally added for realizing automatic hill-holding and the cost control of the whole vehicle is not facilitated due to the fact that information collected by various sensors is combined with the operation decision of a driver to start the automatic hill-holding or not in the current electric vehicle are solved.

Description

Technical Field

[0001] This application relates to the field of electric vehicle technology, and more specifically, to an automatic hill-start assist control method, system, vehicle, and electronic equipment for electric vehicles. Background Technology

[0002] Currently, the most representative method for achieving automatic hill-holding in electric vehicles is to monitor the vehicle's status in real time using the vehicle's ESP (Electronic Stability Program), wheel speed sensors, accelerator pedal sensors, and slope sensors. The system then uses the information collected by each sensor, combined with the driver's actions such as pressing the accelerator and brake pedals, to determine whether to activate automatic hill-holding.

[0003] However, while this method can achieve automatic hill-climbing very accurately by monitoring the vehicle status, it increases the additional hardware requirements, which is not conducive to controlling the overall vehicle cost. Summary of the Invention

[0004] In view of this, the embodiments of this application aim to provide an automatic hill-holding control method, system, vehicle and electronic device for electric vehicles, so as to solve the problem that the current electric vehicles require additional hardware to achieve automatic hill-holding due to the combination of information collected by multiple sensors and driver operation decisions, which is not conducive to the control of the overall vehicle cost.

[0005] In a first aspect, the present invention provides an automatic hill-start assist control method for electric vehicles, comprising: Obtain the first state parameters of the vehicle, which include: gear position and motor position; Based on the gear position and the motor position, it is determined whether the vehicle meets the first preset parking condition. The first preset parking condition is: the gear position is in a gear shifting state and the change in the motor speed is an absolute increase, or the gear position is not in a gear shifting state. After determining that the vehicle meets the first preset parking slope conditions, based on the first state parameters, it is determined whether the vehicle meets the second preset parking slope conditions. After confirming that all the second preset slope-holding conditions are met, enter the slope-holding mode.

[0006] In one possible implementation, the first state parameter further includes: handbrake state, motor controller state, and number of times the vehicle has stopped at a slope; The second preset slope conditions include: Received the enable signal sent by the vehicle controller; The gear position is either forward gear or reverse gear; The handbrake is in the off state; The rotation direction of the motor is not the same as the driving direction corresponding to the gear position, and the speed of the motor meets the preset requirements. The motor does not have any preset faults; The temperature of the motor and the motor controller is less than the preset temperature limit; The number of times the slope was stopped was less than the preset number of times required.

[0007] In one possible implementation, after entering the slope-standing mode, the method further includes: Obtain the duration of stay on the slope; When the parking time reaches the first preset time, the parking torque is paused for a second preset time, and the number of parking times is accumulated.

[0008] In one possible implementation, after entering the slope-standing mode, the method further includes: Receive the requested torque from the vehicle controller; The corresponding hill-start torque is calculated and output based on the motor speed and the requested torque.

[0009] In one possible implementation, after entering the slope-standing mode, the method further includes: The second state parameters of the vehicle are obtained, including: the gear position, the motor position, the handbrake position, the motor controller position, the number of times the vehicle has stopped on a slope, and the foot brake position. Based on the second state parameter, determine whether any preset exit from the slope condition is met; When any of the preset exit conditions for exiting the slope are met, the slope exit mode is exited.

[0010] In one possible implementation, the preset exit conditions for the slope include: Received a shutdown enable signal from the vehicle controller; The gear position is neutral. The handbrake is in the open state; The temperature of the motor and / or motor controller reaches the preset temperature limit; The motor has a preset fault; The requested torque is greater than the hill-holding torque; The absolute value change of the motor speed corresponding to the foot brake closing signal or foot brake travel is less than the preset speed. The number of times the slope was stopped reached the preset requirement.

[0011] In one possible implementation, after exiting the stationary mode, the method further includes: Reset the number of times you stopped at the slope to zero.

[0012] In a second aspect, the present invention provides an automatic hill-start assist control system for electric vehicles, comprising: The acquisition unit is used to acquire the first state parameters of the vehicle, which include: gear position and motor position. The first processing unit is used to determine whether the vehicle meets the first preset parking condition based on the gear position and the motor position. The first preset parking condition is: the gear position is in the gear shifting state and the change in the motor speed is an absolute increase, or the gear position is not in the gear shifting state. The second processing unit is used to determine whether the vehicle meets the second preset parking conditions based on the first state parameters after determining that the vehicle meets the first preset parking conditions. An execution unit is used to enter the slope-holding mode when it is determined that the second preset slope-holding condition is met.

[0013] Thirdly, the present invention provides an electric vehicle, the electric vehicle comprising a vehicle body and an electric vehicle automatic hill-start control system provided in the second aspect of the present invention.

[0014] Fourthly, the present invention provides an electronic device, the electronic device comprising: processor; Memory used to store the processor's executable instructions; The processor is used to execute the electric vehicle automatic hill-holding control method provided in the first aspect of the present invention.

[0015] The automatic hill-holding control method for electric vehicles provided by this invention acquires first state parameters including gear position and motor state. Then, based on the gear position and motor state, it determines whether the vehicle meets a first preset hill-holding condition, specifically whether the gear position is in a gear shifting state and the motor speed change is an absolute increase, or whether the gear position is not in a gear shifting state. After determining that the vehicle meets a second preset hill-holding condition based on the first state parameters, it enters the hill-holding mode. This achieves the distinction between vehicles on flat ground and on slopes without the need for a slope sensor, thus solving the problem of abnormal output torque caused by mistakenly entering a hill-holding position while implementing automatic hill-holding control based on the vehicle's own basic components. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 The diagram shows a flowchart of an automatic hill-climbing control method for electric vehicles provided by an embodiment of the present invention.

[0018] Figure 2 The diagram shows an example of an MCU executing the automatic hill-holding control method for electric vehicles provided in this embodiment of the invention.

[0019] Figure 3 The diagram shows an example of using the automatic hill-start assist method for electric vehicles provided in this embodiment of the invention to perform automatic hill-start assist control on an electric vehicle.

[0020] Figure 4 The diagram shown is a structural diagram of an automatic hill-holding control system for electric vehicles provided in an embodiment of the present invention.

[0021] Figure 5 The diagram shown is a structural schematic of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0022] Unless otherwise defined, the technical or scientific terms used in the embodiments of this specification shall have the ordinary meaning understood by one of ordinary skill in the art to which this specification pertains. The terms "first," "second," and similar terms used in the embodiments of this specification do not indicate any order, quantity, or importance, but are merely used to avoid confusion of constituent elements.

[0023] Unless the context otherwise requires, throughout this specification, "a plurality of" means "at least two," and "including" is interpreted as open-ended or encompassing, that is, "including, but not limited to." In the description of this specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," "specific example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this specification. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example.

[0024] The technical solutions in the embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this specification, and not all embodiments. Based on the embodiments in this specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this specification.

[0025] Currently, activating the automatic hill-hold function requires additional hardware such as a slope sensor, increasing the overall vehicle cost. To address this, methods have emerged that integrate the automatic hill-hold function with the vehicle's own basic components and motor controller. Specifically, when the vehicle is in drive or reverse, with no brake signal and the motor speed within the appropriate range, the vehicle control unit (VCU) sends a hill-hold command to the motor controller (MCU). Upon receiving this command, the MCU initiates speed control, adjusting the output hill-hold torque via a pin PIN. This enables the automatic hill-hold function through the vehicle's gear shifter, accelerator pedal, brake pedal, drive motor, motor controller, and VCU.

[0026] However, while this method enables vehicles to automatically park on slopes without the need for additional hardware, it can lead to accidental entry into parking positions during sudden braking or rapid gear shifting. This results in noticeable vibrations in the vehicle due to abnormal output of parking torque, severely impacting the user experience.

[0027] The present invention aims to solve the above problems. By using the vehicle's own basic components to realize automatic parking, the invention determines whether the vehicle is on a slope based on the vehicle's gear status and the change in motor speed, effectively avoiding the false activation of the automatic parking function, thereby improving the user experience and helping to control the overall vehicle cost.

[0028] Furthermore, the electric vehicle automatic hill-start assist control method provided by the present invention is executed on an electronic device, which is preferably a vehicle motor controller MCU, or a smart terminal such as a smartphone or laptop connected to the MCU, or of course a server on the network side.

[0029] Based on the above, see Figure 1 , Figure 1 This is a flowchart of an automatic hill-holding control method for electric vehicles provided in an embodiment of the present invention, such as... Figure 1 As shown, the process of this method may include: S100, Obtain the first state parameters of the vehicle.

[0030] The first state parameter includes: gear position and motor position.

[0031] Understandably, currently, the vehicle's gear position can be detected by the vehicle's gear position sensor, and the motor position can be acquired by the motor's built-in rotary transformer / encoder.

[0032] Therefore, the first state parameters can all be obtained from the vehicle's inherent sensors, without the need for additional hardware.

[0033] S110. Based on the gear position and motor status, determine whether the vehicle meets the first preset parking slope conditions.

[0034] The first preset slope conditions include: the gear position is in gear switching state and the motor speed change state is an absolute increase, or the gear position is not in gear switching state.

[0035] Specifically, a vehicle on a slope experiences a gravitational force. When in Drive (D) gear, the gravitational force is backward (downhill), and when in Reverse (R) gear, it is forward (uphill). During gear shifting, there is a brief interruption in the torque delivery of the powertrain. The gravitational force directly drives the wheels, causing the motor to rotate and resulting in a rapid increase in the absolute value of the motor speed. For example, when shifting from D to R, the uphill gravitational force causes the motor to reverse and its speed to increase sharply. Conversely, on flat ground, the vehicle is only subject to rolling resistance and air resistance, which are much smaller than the gravitational force on a slope. Therefore, even if the power delivery is interrupted during gear shifting, the motor speed will only change slowly due to basic resistance, and the absolute value of the speed will not increase.

[0036] Furthermore, when the vehicle is not in gear shifting mode and the gear position is stable (such as continuously in D / R gear), the MCU has already counteracted the gravitational force of the slope through torque control. At this time, there is no risk of rolling back, regardless of whether the vehicle is on a slope. Therefore, there is no need to determine whether the vehicle is on a slope.

[0037] Based on this, this embodiment determines whether the vehicle meets the first preset parking slope condition by considering the gear position and motor status. Specifically, if the gear position is in gear shifting mode and the absolute value of the motor speed increase, the vehicle is determined to be on a slope; otherwise, it is on a flat road. If the gear position is not in gear shifting mode, it is directly considered to meet the first preset parking slope condition. This achieves accurate determination of whether the vehicle is on a slope without a slope sensor, thereby avoiding the problem of abnormal output parking torque caused by triggering automatic parking on a flat road, which can cause significant vehicle vibration. This improves the user experience and ensures the accurate triggering of the automatic parking function.

[0038] S120. After determining that the vehicle meets the first preset parking conditions, determine whether the vehicle meets the second preset parking conditions based on the first state parameters.

[0039] Specifically, in a preferred embodiment, the first state parameter further includes: handbrake state, motor controller state, and number of times the vehicle has stopped on a slope; The second pre-set slope conditions include: Received the enable signal sent by the vehicle controller; The gear position is either forward or reverse. The handbrake is in the off state; The direction of motor rotation is inconsistent with the direction of travel corresponding to the gear position, and the motor speed meets the preset requirements. The motor does not have any preset faults; The temperature of the motor and motor controller is lower than the preset temperature limit; The number of times the slope was stopped was less than the preset number of times required.

[0040] Specifically, the status of the handbrake can be detected by the handbrake position switch for mechanical handbrakes, by internal sensors for electronic handbrakes, and by the MCU itself for motor controller status.

[0041] In this embodiment, the MCU is only awakened and able to control the motor after receiving the enable signal from the vehicle controller (VCU), i.e., the VCU enables the MCU (Enable=1). D and R gears are the vehicle's driving gears, and automatic parking is only required under certain conditions in these gears. When the vehicle's handbrake is off, the rear wheels are not locked, and wheel rotation is unrestricted. Under these conditions, automatic parking may be required. When the motor's rotation direction is inconsistent with the vehicle's driving direction corresponding to the gear position, and the motor speed meets preset requirements—for example, in D gear, the motor rotates in the opposite direction and reaches a certain speed, indicating the vehicle is clearly rolling backward; conversely, in R gear, the motor rotates forward and reaches a certain speed, indicating the vehicle is clearly rolling forward—automatic parking is activated to prevent the vehicle from rolling backward.

[0042] Furthermore, the preset fault here refers to a motor fault that prevents the MCU from controlling the motor. Therefore, when a preset fault exists in the motor, the automatic parking function cannot be implemented even if the MCU is activated because it cannot control the motor. It is understandable that excessively high motor temperatures can cause damage or demagnetization, while excessively high motor controller temperatures can lead to hardware damage. The parking torque output by the MCU to the motor during automatic parking causes the motor to heat up. Therefore, activating automatic parking when the temperature of the motor and motor controller exceeds the preset temperature limit will cause the temperature of the motor and motor controller to rise further, potentially damaging them. Similarly, with increasing parking frequency, the motor will also heat up, and prolonged parking may lead to motor overheating and damage.

[0043] Based on this, the second preset hill-climbing conditions include: receiving an enable signal from the vehicle controller; the gear position is forward or reverse; the handbrake is closed; the motor's rotation direction is inconsistent with the driving direction corresponding to the gear position, and the motor's speed meets the preset requirements; the motor does not have any preset faults; the temperature of the motor and the motor controller is lower than the preset temperature limit, and the number of hill-climbing attempts is less than the preset number of attempts.

[0044] In summary, in some possible embodiments, the conditions that the MCU must meet to enter the standby mode include: (1) Enable MCU in VCU (Enable=1); (2) The current gear is D or R; (3) The handbrake is not engaged (HandbrakeSts=0); (4) The direction of motor rotation is inconsistent with the driving intention and the motor speed is -20rpm to -200rpm in D gear and 20rpm to 200rpm in R gear. (5) The motor has no preset faults; (6) The motor temperature is less than 130℃; (7) The temperature of the motor controller is less than 85℃; (8) The number of times the slope is stopped should not exceed three; (9) It is in gear shifting state and the absolute value of the speed increases, or it is not in gear shifting state.

[0045] It should be noted that the motor speed, the preset temperature limit of the motor and controller temperature, and the preset number of times of pausing are all exemplary values ​​in the above embodiments, and not specific limitations. The specific determination methods can be experiments or experience, etc., and no specific restrictions are made here.

[0046] S130. After confirming that the second preset slope-holding conditions are met, enter the slope-holding mode.

[0047] Understandably, various operating conditions can cause a vehicle to accidentally enter a parking slope while driving on flat ground, resulting in abnormal output of parking torque and thus causing noticeable vibration in the vehicle. For example, during emergency braking, when the vehicle is in drive (D) on flat ground, the braking inertia will generate a negative speed, thus achieving the conditions for entering a parking slope.

[0048] The electric vehicle automatic hill-holding control method provided in the above embodiments enters the hill-holding mode only after the vehicle meets all nine conditions (1) to (9) mentioned above. This effectively avoids the problem of the vehicle accidentally entering the hill-holding mode while running on flat ground, thereby ensuring the accuracy of entering the hill-holding mode and improving the user experience. Moreover, the first state parameters used by the MCU to determine whether to enter the hill-holding mode can all be obtained through existing sensors and other hardware on the vehicle. Therefore, accurate control of the automatic parking function is achieved without the need for additional hardware, thereby effectively ensuring the overall vehicle cost.

[0049] In a preferred embodiment, after entering the slope-standing mode, the method further includes: Obtain the duration of stay on the slope; When the parking time reaches the first preset time, the parking torque is paused for the second preset time, and the number of parking times is accumulated.

[0050] In this embodiment, by obtaining the parking time, and when the parking time reaches the first preset time (e.g., 3s, 5s, etc.), the output of parking torque is paused within the second preset time (e.g., 500ms, 800ms, etc.), and the number of parking times is accumulated, the motor overheating that may be caused by prolonged parking is effectively avoided, thereby protecting the motor and improving its service life.

[0051] In a preferred embodiment, after entering the slope-standing mode, the method further includes: Receive the requested torque from the vehicle controller; Calculate and output the corresponding hill-start torque based on the motor speed and requested torque.

[0052] Specifically, when the vehicle meets the conditions for entering the parking mode, the MCU enters the speed control mode, calculates and outputs the corresponding parking torque based on the motor speed and the torque requested by the VCU, which can offset the gravity component of the slope, thereby effectively preventing the vehicle from rolling back.

[0053] Furthermore, in some possible embodiments, such as Figure 2 As shown, the MCU determines the parking condition and sets the parking flag to 0 (PreventSlipFlag=0) when the parking condition is not met, and sets the parking flag to 1 (PreventSlipFlag=1) when the parking condition is met. Combining the motor speed and the torque requested by the VCU, the MCU uses PID control to calculate and output the parking torque, thereby improving the stability, accuracy and speed of parking, and also improving the smoothness of switching between parking mode and drive mode.

[0054] In a preferred embodiment, after entering the slope-standing mode, the method further includes: Obtain the vehicle's second state parameters.

[0055] The second state parameters include: gear position, motor position, handbrake position, motor controller position, number of times the vehicle has stopped, and foot brake position. Based on the second state parameter, determine whether any preset exit condition for the slope is met; Exit the slope-holding mode when any of the preset exit conditions are met.

[0056] Specifically, in a preferred embodiment, the preset exit conditions for the slope include: Received a shutdown enable signal from the vehicle controller; The gear position is neutral; The handbrake is in the open position; The temperature of the motor and / or motor controller has reached the preset temperature limit. The motor has a pre-set fault; The requested torque is greater than the parking torque; The absolute value of the motor speed corresponding to the foot brake closing signal or foot brake travel is less than the preset speed. The number of times the slope was stopped reached the preset requirement.

[0057] In this embodiment, after receiving the enable / disable signal from the VCU, the MCU disables the MCU (Enable=0), and enters a stop or standby state, unable to control the motor. Neutral (N) is the gear where the MCU no longer transmits torque to the motor, cutting off the power connection between the motor and the wheels. When the vehicle's handbrake is engaged, the rear wheels are locked and cannot rotate, eliminating the risk of rolling backward and eliminating the need for automatic parking.

[0058] Furthermore, the preset fault here still refers to a motor fault that prevents the MCU from controlling the motor. Therefore, when a preset fault occurs, the MCU cannot control the motor, so even if the automatic parking function is activated, the function cannot actually be implemented. It is understandable that excessively high motor temperatures can cause damage or demagnetization, while excessively high motor controller temperatures can lead to hardware damage. Therefore, when the temperature of the motor and / or motor controller reaches the preset temperature limit, the automatic parking mode needs to be exited to prevent the temperature of the motor and motor controller from rising further. Similarly, with an increase in the number of parking maneuvers, the motor will also heat up, and prolonged parking may cause the motor to overheat and be damaged.

[0059] Furthermore, when the VCU's requested torque exceeds the parking torque, the automatic parking mode needs to be exited to meet the vehicle's driving needs and avoid torque superposition causing transmission system conflicts. When a foot brake disengagement signal is received (BrakSwitch=0), it indicates the vehicle is preparing to start. At this point, the parking mode needs to be exited to prevent the parking torque from superimposing with the drive torque, causing starting jerking or transmission system shock. When the absolute value of the motor's speed change corresponding to the foot brake travel is less than a preset speed (e.g., when pressing the foot brake reduces the motor speed to less than 5 rpm), it indicates the risk of the vehicle rolling backwards has decreased. Exiting the parking mode avoids limiting power output, thereby improving the smoothness of vehicle start-up.

[0060] Based on this, the preset exit conditions for hill-climbing include: receiving a shutdown enable signal from the vehicle controller; the gear position is neutral; the handbrake is in the open state; the temperature of the motor and / or the motor controller reaches a preset temperature limit; the motor experiences a preset fault; the requested torque is greater than the hill-climbing torque; a foot brake shutdown signal is obtained or the absolute value change of the motor speed corresponding to the foot brake travel is less than the preset speed; and the number of hill-climbing attempts reaches the preset number requirement.

[0061] In summary, in some possible embodiments, any of the conditions that the MCU must meet to exit the parking mode include: (1) Disable VCU and enable MCU (Enable=0); (2) The gear position is N; (3) The handbrake is in the engaged state (HandbrakeSts=1); (4) A preset fault occurs in the motor system; (5) The motor temperature is greater than 130℃; (6) The temperature of the motor controller is greater than 85℃; (7) The VCU requests a torque greater than the parking torque; (8) Release the foot brake (BrakSwitch=0) or press the foot brake to make the absolute value of the motor speed less than 5 rpm; (9) The number of times the slope is stopped reaches three times.

[0062] It should be noted that the absolute value of motor speed, the preset temperature limit of motor and controller temperature, and the preset number of times of pausing involved in the above embodiments are all exemplary values, not specific limitations. The specific determination methods can be experiments or experience, etc., and no specific restrictions are made here.

[0063] In a preferred embodiment, after exiting the hill-climbing mode, the method further includes: Reset the number of times you stayed at the slope to zero.

[0064] Specifically, when the MCU exits the hill-holding mode, it indicates that the vehicle no longer needs automatic parking or the conditions for automatic parking are not met. At this time, resetting the hill-holding count to zero allows the count to be recalculated the next time automatic parking is started. This prevents the motor or motor controller from overheating and being damaged due to excessive hill-holding counts or long hill-holding times during the next hill-holding attempt.

[0065] In summary, see Figure 3 This is a flowchart illustrating an example of using the automatic hill-start assist method for electric vehicles provided in the above embodiments to perform automatic hill-start assist control on an electric vehicle. For example... Figure 3 As shown, the process includes the following steps: Step S1: The MCU has not entered the parking mode. The vehicle is in its initial state, and the parking flag is 0 (PreventSlipFlag=0). Step S2: Determine whether the vehicle meets all of the following conditions. If it does not meet any of the following conditions, proceed to step S3. If it does meet the conditions, proceed to step S4. (1) Enable MCU in VCU (Enable=1); (2) The current gear is D or R; (3) The handbrake is not engaged (HandbrakeSts=0); (4) The direction of motor rotation is inconsistent with the driving intention and the motor speed is -25rpm to -220rpm in D gear and 25rpm to 220rpm in R gear. (5) The motor has no preset faults; (6) The motor temperature is less than 120℃; (7) The temperature of the motor controller is less than 90℃; (8) The number of times the slope is stopped should not exceed four; (9) It is in gear shifting state and the absolute value of the speed increases, or it is not in gear shifting state.

[0066] Step S3: The MCU does not enter the slope-holding mode, and the slope-holding flag is set to 0 (PreventSlipFlag=0); Step S4: The MCU enters the parking mode, and the parking flag is set to 1 (PreventSlipFlag=1). Based on the motor speed and the torque requested by the VCU, the PID control is used to calculate and output the corresponding parking torque to prevent the vehicle from rolling backward or forward. Step S5: Determine whether the vehicle meets any of the following conditions. If not all conditions are met, proceed to step S6; if any condition is met, proceed to step S7. (1) Disable VCU and enable MCU (Enable=0); (2) The gear position is N; (3) The handbrake is in the engaged state (HandbrakeSts=1); (4) A preset fault occurs in the motor system; (5) The motor temperature is greater than 120℃; (6) The temperature of the motor controller is greater than 90℃; (7) The VCU requests a torque greater than the parking torque; (8) Release the foot brake (BrakSwitch=0) or press the foot brake to make the absolute value of the motor speed less than 8 rpm; (9) The number of times the slope was stopped reached four times.

[0067] Step S6: The MCU maintains the slope-holding mode, the slope-holding flag is set to 1 (PreventSlipFlag=1), and the number of slope-holding times is accumulated; Step S7: The MCU exits the slope-holding mode, the slope-holding flag is set to 0 (PreventSlipFlag=0), and the number of slope-holding attempts is cleared to 0.

[0068] Depend on Figure 3 As can be seen, the electric vehicle automatic hill-holding control method provided in the above embodiments can realize the automatic hill-holding function based on MCU, effectively reduce the vehicle hardware installation cost, and can also complete the validity judgment of the vehicle being on flat ground and slope, thereby reducing the probability of the vehicle accidentally entering the hill-holding mode under special working conditions. It can be effectively implemented in the vehicle testing and mass production stages.

[0069] The following describes an automatic hill-holding control system for electric vehicles provided by an embodiment of the present invention. The automatic hill-holding control system described below can be considered as a modular architecture for implementing an automatic hill-holding control method for electric vehicles provided by an embodiment of the present invention; the following description can be referenced in conjunction with the above.

[0070] See Figure 4 , Figure 4 This is a structural block diagram of an automatic hill-holding control system for electric vehicles provided in an embodiment of the present invention. The system may include: The acquisition unit 10 is used to acquire the first state parameters of the vehicle, which include: gear position and motor position. The first processing unit 20 is used to determine whether the vehicle meets the first preset parking condition based on the gear position and the motor position. The first preset parking condition is: the gear position is in the gear shifting state and the motor speed change is an absolute increase, or the gear position is not in the gear shifting state. The second processing unit 30 is used to determine whether the vehicle meets the second preset parking conditions based on the first state parameters after determining that the vehicle meets the first preset parking conditions. The execution unit 40 is used to enter the slope-holding mode when it is determined that the second preset slope-holding condition is met.

[0071] Optionally, the first state parameters may also include: handbrake status, motor controller status, and number of times the vehicle has stopped on a slope; The second pre-set slope conditions include: Received the enable signal sent by the vehicle controller; The gear position is either forward or reverse. The handbrake is in the off state; The direction of motor rotation is inconsistent with the direction of travel corresponding to the gear position, and the motor speed meets the preset requirements. The motor does not have any preset faults; The temperature of the motor and motor controller is lower than the preset temperature limit; The number of times the slope was stopped was less than the preset number of times required.

[0072] Optionally, execution unit 40 is also used for: Obtain the duration of stay on the slope; When the parking time reaches the first preset time, the parking torque is paused for the second preset time, and the number of parking times is accumulated.

[0073] Optionally, execution unit 40 is also used for: Receive the requested torque from the vehicle controller; Calculate and output the corresponding hill-start torque based on the motor speed and requested torque.

[0074] Optionally, the acquisition unit 10 is also used to acquire the vehicle's second state parameters, which include: gear position, motor position, handbrake position, motor controller position, number of times the vehicle has stopped on a slope, and foot brake position. The second processing unit 30 is also used to determine, based on the second state parameter, whether any preset exit from the slope condition is met. The execution unit 40 is also used to exit the slope-holding mode when it is determined that any preset exit slope-holding condition is met.

[0075] Optional, preset exit conditions for hillside parking include: Received a shutdown enable signal from the vehicle controller; The gear position is neutral; The handbrake is in the open position; The temperature of the motor and / or motor controller has reached the preset temperature limit. The motor has a pre-set fault; The requested torque is greater than the parking torque; The absolute value of the motor speed corresponding to the foot brake closing signal or foot brake travel is less than the preset speed. The number of times the slope was stopped reached the preset requirement.

[0076] Optionally, execution unit 40 is also used for: Reset the number of times you stayed at the slope to zero.

[0077] Optionally, embodiments of the present invention also provide an electric vehicle, which includes a vehicle body and an electric vehicle automatic hill-start control system as provided in any of the above embodiments.

[0078] Below, for reference Figure 5 The electronic device provided in the embodiments of this application can be described as follows: at least one processor 100, at least one communication interface 200, at least one memory 300 and at least one communication bus 400; In this embodiment of the invention, the number of processor 100, communication interface 200, memory 300, and communication bus 400 is at least one, and the processor 100, communication interface 200, and memory 300 communicate with each other through communication bus 400; obviously, Figure 5 The communication connections shown for the processor 100, communication interface 200, memory 300, and communication bus 400 are optional. Optionally, the communication interface 200 can be an interface of a communication module, such as the interface of a GSM module; the processor 100 may be a central processing unit (CPU), an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement embodiments of the present invention.

[0079] The memory 300 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0080] Specifically, the processor 100 is used to execute the application program in the memory to implement the steps of the above-described electric vehicle automatic hill-start control method.

[0081] The basic principles of this application have been described above with reference to specific embodiments. However, it should be noted that the advantages, benefits, and effects mentioned in this application are merely examples and not limitations, and should not be considered as essential features of each embodiment of this application. Furthermore, the specific details disclosed above are for illustrative and facilitative purposes only, and are not limitations. These details do not limit the application to the necessity of employing the aforementioned specific details for implementation.

[0082] The block diagrams of devices, apparatuses, devices, and systems involved in this application are merely illustrative examples and are not intended to require or imply that they must be connected, arranged, or configured in the manner shown in the block diagrams. As those skilled in the art will recognize, these devices, apparatuses, devices, and systems can be connected, arranged, and configured in any manner. Words such as “comprising,” “including,” “having,” etc., are open-ended terms meaning “including but not limited to,” and are used interchangeably with them. The terms “or” and “and” as used herein refer to the terms “and / or,” and are used interchangeably with them unless the context clearly indicates otherwise. The term “such as” as used herein refers to the phrase “such as but not limited to,” and is used interchangeably with it.

[0083] It should also be noted that in the apparatus, equipment, and methods of this application, the components or steps can be disassembled and / or recombined. These disassemblies and / or recombinations should be considered as equivalent solutions of this application.

[0084] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects without departing from the scope of this application. Therefore, this application is not intended to be limited to the aspects shown herein, but rather to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0085] It should be understood that the qualifiers “first,” “second,” “third,” “fourth,” “fifth,” and “sixth” used in the description of the embodiments of this application are only used to more clearly illustrate the technical solutions and are not intended to limit the scope of protection of this application.

[0086] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this application to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations thereof.

Claims

1. An automatic hill-start assist control method for electric vehicles, characterized in that, include: Obtain the first state parameters of the vehicle, which include: gear position and motor position; Based on the gear position and the motor position, it is determined whether the vehicle meets the first preset parking condition. The first preset parking condition is: the gear position is in a gear shifting state and the change in the motor speed is an absolute increase, or the gear position is not in a gear shifting state. After determining that the vehicle meets the first preset parking slope conditions, based on the first state parameters, it is determined whether the vehicle meets the second preset parking slope conditions. After confirming that the second preset slope-holding condition is met, the slope-holding mode is entered.

2. The method according to claim 1, characterized in that, The first state parameter also includes: handbrake state, motor controller state, and number of times the vehicle has stopped on a slope; The second preset slope conditions include: Received the enable signal sent by the vehicle controller; The gear position is either forward gear or reverse gear; The handbrake is in the off state; The rotation direction of the motor is not the same as the driving direction corresponding to the gear position, and the speed of the motor meets the preset requirements. The motor does not have any preset faults; The temperature of the motor and the motor controller is less than the preset temperature limit; The number of times the slope was stopped was less than the preset number of times required.

3. The method according to claim 2, characterized in that, After entering the slope-standing mode, it also includes: Obtain the duration of stay on the slope; When the parking time reaches the first preset time, the parking torque is paused for a second preset time, and the number of parking times is accumulated.

4. The method according to claim 1, characterized in that, After entering the slope-standing mode, it also includes: Receive the requested torque from the vehicle controller; The corresponding hill-start torque is calculated and output based on the motor speed and the requested torque.

5. The method according to claim 4, characterized in that, After entering the slope-standing mode, it also includes: The second state parameters of the vehicle are obtained, including: the gear position, the motor position, the handbrake position, the motor controller position, the number of times the vehicle has stopped on a slope, and the foot brake position. Based on the second state parameter, determine whether any preset exit condition for the slope is met; When any of the preset exit conditions for exiting the slope are met, the slope exit mode is exited.

6. The method according to claim 5, characterized in that, The preset exit conditions for the slope include: Received a shutdown enable signal from the vehicle controller; The gear position is neutral. The handbrake is in the open state; The temperature of the motor and / or motor controller reaches the preset temperature limit; The motor has a preset fault; The requested torque is greater than the hill-holding torque; The absolute value change of the motor speed corresponding to the foot brake closing signal or foot brake travel is less than the preset speed. The number of times the slope was stopped reached the preset requirement.

7. The method according to claim 5, characterized in that, After exiting the stationary mode, the following is also included: Reset the number of times you stopped at the slope to zero.

8. An automatic hill-start assist control system for electric vehicles, characterized in that, include: The acquisition unit is used to acquire the first state parameters of the vehicle, which include: gear position and motor position. The first processing unit is used to determine whether the vehicle meets the first preset parking condition based on the gear position and the motor position. The first preset parking condition is: the gear position is in the gear shifting state and the change in the motor speed is an absolute increase, or the gear position is not in the gear shifting state. The second processing unit is used to determine whether the vehicle meets the second preset parking conditions based on the first state parameters after determining that the vehicle meets the first preset parking conditions. The execution unit is used to enter the slope-holding mode when it is determined that all the second preset slope-holding conditions are met.

9. An electric vehicle, characterized in that, The electric vehicle includes a vehicle body and an electric vehicle automatic hill-start assist control system as described in claim 8.

10. An electronic device, characterized in that, The electronic device includes: processor; Memory used to store the processor's executable instructions; The processor is configured to perform the method described in any one of claims 1 to 7.

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