Vehicle speed control method and device and vehicle

Abstract

The invention relates to a vehicle speed control method and device and a vehicle, and the method comprises the steps: determining a load parameter of the vehicle according to the vehicle speed and the longitudinal acceleration of the vehicle; determining an initial speed limit value according to the load parameter and the battery remaining capacity of the vehicle; according to the accelerator opening degree and the accelerator opening degree change rate of the vehicle, an initial vehicle speed compensation value of the vehicle is determined; adjusting the initial vehicle speed compensation value in the current period by using the initial vehicle speed compensation value in the historical period to obtain a target vehicle speed compensation value in the current period; determining a target speed limit value in the next period according to the initial speed limit value and the target vehicle speed compensation value; and limiting the speed of the vehicle in the next period according to the target speed limiting value. The speed of the vehicle is controlled by calculating the accurate target speed limit value, so that the problem of inaccurate speed limit of the vehicle is solved.

Description

Technical Field

[0001] This invention relates to the field of vehicle speed limiting technology, specifically to a vehicle speed control method, device, and vehicle. Background Technology

[0002] During vehicle operation, if the driver accelerates hard, the vehicle will gain strong acceleration power, provided the battery and electric drive capabilities are sufficient. However, the vehicle's rolling resistance increases with speed, and environmental factors such as road surface wetness, weather conditions, vehicle load, and vehicle age all affect stable driving. Therefore, it is necessary to limit the vehicle's speed to a certain extent.

[0003] In existing technologies, speed limits are usually determined based on vehicle speed and road conditions, which leads to inaccurate speed limits. Summary of the Invention

[0004] This application provides a vehicle speed control method, device, and vehicle to solve the problem of inaccurate vehicle speed limits.

[0005] In a first aspect, this application provides a vehicle speed control method, comprising: determining vehicle load parameters based on vehicle speed and longitudinal acceleration; determining an initial speed limit based on the load parameters and remaining battery charge; determining an initial speed compensation value based on throttle opening and throttle opening rate of change; adjusting the initial speed compensation value for the current period using the initial speed compensation value from a historical period to obtain a target speed compensation value for the current period; determining a target speed limit for the next period based on the initial speed limit and the target speed compensation value; and limiting the vehicle speed in the next period based on the target speed limit.

[0006] For example, determining the vehicle's load parameters based on the vehicle's speed and longitudinal acceleration includes: acquiring the vehicle's speed and longitudinal acceleration in each cycle using sensors; determining the ratio of the vehicle speed change to time as the vehicle speed acceleration in the cycle; determining the difference between the vehicle's longitudinal acceleration and the vehicle speed acceleration in the cycle as the initial value of the load parameters in the cycle; and performing a first-order low-pass filter on the initial load parameters for each cycle to obtain the load parameters for each cycle.

[0007] This application calculates the vehicle's speed acceleration and longitudinal acceleration to determine the difference between them, and further obtains load parameters that represent this difference to indicate the vehicle's load condition. This allows for the acquisition of accurate load parameters based on the vehicle's load. Furthermore, low-pass filtering is used to improve the accuracy of the load parameters.

[0008] For example, determining the initial speed limit based on load parameters and the vehicle's remaining battery charge includes calculating the initial speed limit using the following formula:

[0009] Where v is the initial speed limit, Po is the power of the vehicle's range extender at its optimal energy consumption operating point, and Pc is the power consumed by the entire vehicle. For the efficiency of the entire vehicle system, Where Ps is the battery output system efficiency, m is the vehicle's battery continuous discharge power, g is the vehicle weight, f is the gravitational acceleration, q is the rolling friction coefficient, and a is the vehicle's required acceleration.

[0010] This application calculates the initial speed limit value using the above formula, thereby calculating an accurate initial speed limit value based on the vehicle's remaining battery power and load parameters, which can then be used to calculate the target speed limit value, thus improving the accuracy of vehicle speed limits.

[0011] For example, determining the initial vehicle speed compensation value based on the vehicle's throttle opening and throttle opening change rate includes: acquiring the vehicle's throttle opening in each cycle through sensors; comparing the difference between the throttle opening and the throttle opening in the previous cycle with the cycle time to obtain the throttle opening change rate in the current cycle; setting the dynamic flag to a set state when the throttle opening is greater than the opening threshold and the throttle opening change rate is greater than the change rate threshold, otherwise setting the dynamic flag to a reset state; when the dynamic flag is set, the initial vehicle speed compensation value is a preset value, and when the dynamic flag is reset, the initial vehicle speed compensation value is zero.

[0012] This application determines the state of the dynamic flag position based on the throttle opening and the rate of change of the throttle opening, and further determines the magnitude of the initial vehicle speed compensation value. Thus, the initial vehicle speed compensation value is obtained based on the driver's acceleration and deceleration intentions, which makes the final calculated target speed limit value more accurate.

[0013] For example, when the throttle opening is greater than the opening threshold and the rate of change of the throttle opening is greater than the rate of change threshold, after setting the state of the dynamic flag bit to the set state, the above method further includes: starting a timer; when the timer's duration exceeds a preset duration, setting the state of the dynamic flag bit to the reset state.

[0014] In this application, after the timer's duration exceeds a preset duration, the state of the dynamic flag is reset. The purpose of this strategy is to avoid the dynamic flag remaining in the set state for an extended period, resulting in a non-zero initial vehicle speed compensation value and thus causing the final calculated target speed limit value to be too large, failing to achieve an accurate speed limiting effect.

[0015] For example, the preset duration and preset value are determined based on the vehicle's overtaking distance.

[0016] This application uses distance to determine the preset duration and preset value, which is more accurate than setting the preset duration and preset value based on experience.

[0017] For example, adjusting the initial vehicle speed compensation value for the current period using the initial vehicle speed compensation value from the historical period to obtain the target vehicle speed compensation value for the current period includes: when the initial vehicle speed compensation value for the current period is less than the initial vehicle speed compensation value for the previous period, determining a first compensation value difference between the initial vehicle speed compensation value for the previous period and the target vehicle speed compensation value for the previous period; adding a first threshold to the initial vehicle speed compensation value for the current period to obtain the target vehicle speed compensation value for the current period, wherein the first threshold is greater than or equal to the absolute value of the first compensation value difference; when the initial vehicle speed compensation value for the current period is greater than the initial vehicle speed compensation value for the previous period, determining a second compensation value difference between the initial vehicle speed compensation value for the previous period and the target vehicle speed compensation value for the previous period; and subtracting the second threshold from the initial vehicle speed compensation value for the current period to obtain the target vehicle speed compensation value for the current period, wherein the second threshold is greater than or equal to the absolute value of the second compensation value difference, and the second threshold is less than the first threshold.

[0018] This application obtains the target speed compensation value by adjusting the initial speed compensation value in different cycles, and determines a more accurate target speed compensation value by comparing the initial speed compensation value in each cycle. This improves the accuracy of the target speed limit value, and also improves the overtaking efficiency before overtaking and the overtaking safety after overtaking.

[0019] For example, limiting the vehicle speed in the next cycle based on the target speed limit includes: calculating the speed deviation based on the vehicle speed and the target speed limit; calculating the wheel end torque deviation based on the speed deviation; determining the current maximum wheel end torque based on the vehicle speed; adjusting the current maximum wheel end torque using the wheel end torque deviation to obtain the target maximum wheel end torque; and controlling the vehicle's maximum torque to be less than the target maximum wheel end torque.

[0020] This application limits the vehicle speed by controlling the wheel-end torque, thereby ensuring that the vehicle's real-time speed does not exceed the target speed limit value within the cycle, thus improving the accuracy of vehicle speed limiting.

[0021] Secondly, this application provides a vehicle speed control device, comprising: a first determining module for determining vehicle load parameters based on vehicle speed and longitudinal acceleration; a second determining module for determining an initial speed limit value based on the load parameters and remaining battery charge; a third determining module for determining an initial speed compensation value based on throttle opening and throttle opening change rate; an adjusting module for adjusting the initial speed compensation value for the current period using the initial speed compensation value from a historical period to obtain a target speed compensation value for the current period; a fourth determining module for determining a target speed limit value for the next period based on the initial speed limit value and the target speed compensation value; and a speed limiting module for limiting the vehicle speed in the next period based on the target speed limit value.

[0022] Thirdly, this application provides a vehicle, including: a speed limiting module, used to determine the vehicle's load parameters based on the vehicle's speed and longitudinal acceleration; determine an initial speed limit value based on the load parameters and the vehicle's remaining battery charge; determine an initial speed compensation value based on the vehicle's throttle opening and throttle opening change rate; adjust the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain a target speed compensation value for the current period; determine a target speed limit value for the next period based on the initial speed limit value and the target speed compensation value; and an execution module, used to limit the vehicle's speed in the next period based on the target speed limit value.

[0023] Fourthly, this application provides an apparatus comprising: at least one communication interface; at least one bus connected to the at least one communication interface; at least one processor connected to the at least one bus; and at least one memory connected to the at least one bus, wherein the processor is configured to: determine vehicle load parameters based on vehicle speed and vehicle longitudinal acceleration; determine an initial speed limit value based on the load parameters and the remaining battery charge of the vehicle; determine an initial speed compensation value based on the vehicle throttle opening and throttle opening change rate; adjust the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain a target speed compensation value for the current period; determine a target speed limit value for the next period based on the initial speed limit value and the target speed compensation value; and limit the vehicle speed based on the target speed limit value.

[0024] Fifthly, this application also provides a computer storage medium storing computer-executable instructions for executing the vehicle speed control method of any of the above claims of this application.

[0025] The beneficial effects of this application are: This application determines the vehicle's load parameters based on its speed and longitudinal acceleration; determines the initial speed limit based on the load parameters and the vehicle's remaining battery power; determines the initial speed compensation value based on the throttle opening and its rate of change; adjusts the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain the target speed compensation value for the current period; determines the target speed limit for the next period based on the initial speed limit and the target speed compensation value; and limits the vehicle's speed based on the target speed limit in the next period. This method allows for the determination of the vehicle's load parameters based on its speed and longitudinal acceleration, representing its load status. Furthermore, it determines the initial speed limit based on the load parameters and the vehicle's remaining battery power, and further uses the throttle opening and its rate of change to determine the target speed compensation value, compensating for the initial speed limit to obtain the target speed limit value, which represents the vehicle's acceleration and deceleration. Using the target speed limit value for vehicle speed limiting improves the accuracy of vehicle speed limiting. Attached Figure Description

[0026] Figure 1 This is a flowchart of a vehicle speed control method according to this application; Figure 2 This is a schematic diagram illustrating the determination of a target speed limit value according to this application; Figure 3 This is a schematic diagram illustrating one method of determining load parameters according to this application; Figure 4 This is a schematic diagram illustrating an adjustment of a dynamic marker according to this application; Figure 5 This is a schematic diagram illustrating one method for determining the target maximum wheel end torque according to this application; Figure 6 This is a schematic diagram of a vehicle speed control device according to this application; Figure 7 This is a schematic diagram of a vehicle speed control device according to this application. Detailed Implementation

[0027] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0028] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of this application. Therefore, the drawings only show the components related to this application and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0029] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0030] To address the technical problem of inaccurate vehicle speed limits in existing technologies, this application provides a vehicle speed control method that can improve the accuracy of vehicle speed limits.

[0031] Figure 1 A flowchart of a vehicle speed control method provided in this application embodiment includes: S101, Determine the vehicle's load parameters based on the vehicle's speed and longitudinal acceleration; S102, determine the initial speed limit value based on the load parameters and the remaining battery power of the vehicle; S103, determine the initial vehicle speed compensation value based on the vehicle's throttle opening and throttle opening change rate; S104, use the initial vehicle speed compensation value in the historical period to adjust the initial vehicle speed compensation value in the current period to obtain the target vehicle speed compensation value in the current period; S105, determine the target speed limit for the next cycle based on the initial speed limit and the target vehicle speed compensation value; S106, based on the target speed limit value, limits the vehicle speed in the next cycle.

[0032] This application can be applied to speed limiting of vehicles in driving scenarios. The purpose of vehicle speed limiting is to ensure that the vehicle's speed does not exceed the target speed limit during driving. If the target speed limit is exceeded, the vehicle speed should be reduced to the target speed limit, or, if the vehicle speed is about to reach the target speed limit, the speed should not increase further even with increased throttle opening, thus avoiding exceeding the target speed limit. This improves driving safety and prevents accidents caused by excessive speed. Vehicles can be pure electric vehicles (BEVs), hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), extended-range electric vehicles (EREVs), or fuel cell electric vehicles (FCEVs), etc.

[0033] In this application, when limiting the speed of a vehicle, an initial speed limit value can be determined first. This initial speed limit value is determined based on load parameters and the remaining battery charge. Load parameters represent the vehicle's load condition and can be calculated based on the vehicle's speed and longitudinal acceleration. The remaining battery charge represents the battery's charge level and can be directly measured. Furthermore, a target speed compensation value can be determined. The target speed compensation value is used to compensate for the initial speed limit value, resulting in the target speed limit. The target speed compensation value is determined by adjusting the initial speed compensation value. The initial speed compensation value can be determined based on the vehicle's throttle opening and its rate of change, representing the driver's acceleration and deceleration intentions.

[0034] In this application, when limiting the speed of a vehicle, instead of determining a target speed limit and then using that target speed limit indefinitely, a time period is divided. A target speed limit is determined for each period, and the vehicle speed is limited according to that target speed limit in the next period. For example, the time period can be 1 second, 3 seconds, 10 seconds, etc., but is not limited to these.

[0035] Figure 2This is a schematic diagram illustrating the determination of the target speed limit in this example. Taking the target speed limit within a time period as an example, in the process of determining the target speed limit, the vehicle's speed, longitudinal acceleration, remaining battery charge, throttle opening, and rate of change of throttle opening are acquired within the current period. The speed can be obtained through sensors and is the vehicle's real-time speed. The longitudinal acceleration is the acceleration component of the vehicle along the travel direction (i.e., the forward and backward direction), reflecting the rate of change of vehicle speed in the forward and backward direction. Based on the speed and longitudinal acceleration, load parameters can be calculated, which represent the vehicle's load condition. Specifically, vehicle speed acceleration can be calculated from speed, and the load parameters are calculated based on the difference between vehicle speed acceleration and longitudinal acceleration. The greater the difference between vehicle speed acceleration and longitudinal acceleration, the greater the vehicle's load.

[0036] The remaining battery power can be obtained by detecting the battery status, which can be expressed as a percentage or read as a numerical value. The remaining battery power directly reflects the amount of battery capacity. Based on the load parameters and the remaining battery power, the initial speed limit value is determined.

[0037] The initial speed limit is an intermediate value obtained during the calculation process. While directly using the initial speed limit to limit the vehicle's speed can achieve the desired effect, it is not the optimal solution. In this application, a target speed compensation value can be calculated to adjust the initial speed limit, thus obtaining the target speed limit. The target speed compensation value is obtained by adjusting the initial speed compensation value. The initial speed compensation value can be calculated based on the throttle opening and the rate of change of throttle opening. Throttle opening refers to the angle at which the throttle is open compared to when it is not depressed. The greater the force applied when the throttle is depressed, the greater the throttle opening. A greater throttle opening results in more battery power, leading to a faster vehicle speed in the same gear. The rate of change of throttle opening refers to the rate of change of throttle opening per unit time. A larger rate of change of throttle opening indicates a faster change in throttle speed per unit time, which can be understood as the throttle being rapidly depressed or released.

[0038] After calculating the initial vehicle speed compensation value using the throttle opening and its rate of change, the initial speed compensation value is adjusted, such as through filtering or accuracy verification, to obtain the target speed compensation value. This target speed compensation value is then used to compensate for the initial speed limit, either by adding the two values ​​together, or by multiplying the target speed compensation value by a weight and then adding it to the initial speed limit value, to obtain the target speed limit. The target speed limit value is then used to limit the vehicle's speed.

[0039] In this application, a target speed limit can be calculated for each time period, and the speed limit can be implemented in the next period. Alternatively, in another approach, data can be acquired once or multiple times at the beginning of the period to calculate the target speed limit for that period, and the speed limit can be implemented within that period.

[0040] This application determines the vehicle's load parameters based on its speed and longitudinal acceleration; determines the initial speed limit based on the load parameters and the vehicle's remaining battery power; determines the initial speed compensation value based on the throttle opening and its rate of change; adjusts the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain the target speed compensation value for the current period; determines the target speed limit for the next period based on the initial speed limit and the target speed compensation value; and limits the vehicle's speed based on the target speed limit in the next period. This method allows for the determination of the vehicle's load parameters based on its speed and longitudinal acceleration, representing its load status. Furthermore, it determines the initial speed limit based on the load parameters and the vehicle's remaining battery power, and further uses the throttle opening and its rate of change to determine the target speed compensation value, compensating for the initial speed limit to obtain the target speed limit value, which represents the vehicle's acceleration and deceleration. Using the target speed limit value for vehicle speed limiting improves the accuracy of vehicle speed limiting.

[0041] For example, determining the vehicle's load parameters based on the vehicle's speed and longitudinal acceleration includes: acquiring the vehicle's speed and longitudinal acceleration in each cycle using sensors; determining the ratio of the vehicle speed change to time as the vehicle speed acceleration in the cycle; determining the difference between the vehicle's longitudinal acceleration and the vehicle speed acceleration in the cycle as the initial value of the load parameters in the cycle; and performing a first-order low-pass filter on the initial load parameters for each cycle to obtain the load parameters for each cycle.

[0042] In this example, when calculating the vehicle's load parameters based on its speed and longitudinal acceleration, the vehicle's speed and longitudinal acceleration can be obtained using sensors on the vehicle, such as speed sensors and longitudinal acceleration sensors. Data can be acquired separately for each time period. For example, to acquire vehicle speed, one or more speed measurements can be taken within each time period, and the acquired speed or its average value can be used as the speed data acquired within that time period.

[0043] Figure 3 This is a schematic diagram illustrating how load parameters are determined. For data within a single cycle, after acquiring the vehicle speed, the difference between the vehicle speed and the speed of the previous cycle is calculated to obtain the speed change, Z. -1 Using data from the previous period, the change in speed is compared to the period time to obtain the vehicle acceleration, where Ts represents the period time. Vehicle acceleration indicates the change in vehicle speed.

[0044] After obtaining the vehicle speed acceleration, the vehicle speed acceleration is subtracted from the vehicle's longitudinal acceleration, and the difference is used as the initial value of the load parameter within the cycle. This initial value of the load parameter represents the difference between the vehicle's speed acceleration and longitudinal acceleration within that cycle, and this difference is caused by the vehicle's load. Therefore, this initial value of the load parameter represents the vehicle's load condition. It should be noted that the load condition mentioned in this application can be caused by factors such as the vehicle's own weight, the weight of the people or objects being carried, and the road gradient.

[0045] After obtaining the initial values ​​of the load parameters, a first-order low-pass filter can be applied to the initial values ​​of the load parameters for each cycle, with a filter coefficient of Ta. The first-order low-pass filter can suppress or attenuate sudden increases in the initial values ​​of the load parameters for each cycle, removing interference and obtaining accurate and stable load parameters.

[0046] This application calculates the vehicle's speed acceleration and longitudinal acceleration to determine the difference between them, and further obtains load parameters that represent this difference to indicate the vehicle's load condition. This allows for the acquisition of accurate load parameters based on the vehicle's load. Furthermore, low-pass filtering is used to improve the accuracy of the load parameters.

[0047] For example, determining the initial speed limit based on load parameters and the vehicle's remaining battery charge includes calculating the initial speed limit using the following formula: (1) Where v is the initial speed limit, Po is the power of the vehicle's range extender at its optimal energy consumption operating point, and Pc is the power consumed by the entire vehicle. For the efficiency of the entire vehicle system, Where Ps is the battery output system efficiency, m is the vehicle's battery continuous discharge power, g is the vehicle weight, f is the gravitational acceleration, q is the rolling friction coefficient, and a is the vehicle's required acceleration.

[0048] This application can calculate the initial speed limit of the vehicle using Formula 1 above. Formula 1 is obtained through the following process: First, calculate the available drive power provided by the range extender: Pe = (Po - Pc) × η′, where Pe represents the available drive power provided by the range extender, Po represents the power output by the range extender at its optimal energy consumption operating point, and Pc represents the power consumed by the vehicle's accessories. The system efficiency is calculated as follows: The power required for uniform vehicle operation is: P′ = mgv × (f + i), where P′ represents the vehicle's operating power, m represents the vehicle weight, g represents gravitational acceleration, v represents the vehicle speed, f represents the rolling friction coefficient, and i represents the slope. The power required for vehicle acceleration is: P″ = mav, where a is the required acceleration. The continuous discharge power of the power battery decreases as the remaining battery charge decreases, denoted by Ps. The total available driving power is calculated as: Pq = Pe + Ps × η″, where η″ is the battery output system efficiency. The power required for vehicle movement is calculated as: Pd = P′ + P″. When the power required for vehicle movement equals the total available driving power, i.e., Pd equals Pq, the following formula 2 can be obtained from the above calculation process: (2) Within a slope of less than 20%, the load parameter is approximately equal to the product of the slope and the acceleration due to gravity. Therefore, the formula for calculating the initial speed limit is Formula 1 above. q is the load parameter.

[0049] This application calculates the initial speed limit value using the aforementioned formula 1, thereby enabling the calculation of an accurate initial speed limit value based on the vehicle's remaining battery power and load parameters. This initial speed limit value can then be used to calculate the target speed limit value, thus improving the accuracy of vehicle speed limits.

[0050] For example, determining the initial vehicle speed compensation value based on the vehicle's throttle opening and throttle opening change rate includes: acquiring the vehicle's throttle opening in each cycle through sensors; comparing the difference between the throttle opening and the throttle opening in the previous cycle with the cycle time to obtain the throttle opening change rate in the current cycle; setting the dynamic flag to a set state when the throttle opening is greater than the opening threshold and the throttle opening change rate is greater than the change rate threshold, otherwise setting the dynamic flag to a reset state; when the dynamic flag is set, the initial vehicle speed compensation value is a preset value, and when the dynamic flag is reset, the initial vehicle speed compensation value is zero.

[0051] Figure 4This is a schematic diagram illustrating the determination of the initial vehicle speed compensation value in this application. In this example, when calculating the initial vehicle speed compensation value based on the throttle opening and the throttle opening change rate, the throttle opening of the vehicle in each cycle can be obtained through sensors on the vehicle, such as a throttle opening sensor. The throttle opening change rate is then calculated based on the ratio of the change in throttle opening to time. For a single cycle, the throttle opening may have multiple different values; therefore, the average throttle opening value can be used as the throttle opening data for that cycle. The throttle opening change rate can be obtained by comparing the maximum change in throttle opening within the cycle to the cycle time. For example, if the maximum throttle opening within the cycle is 80 degrees and the minimum is 60 degrees, then the maximum change in throttle opening within the cycle is 20 degrees, which is then compared to the cycle time to obtain the throttle opening change rate. Alternatively, the value of the fastest change in throttle opening within the cycle can be determined as the throttle opening change rate. For example, the moment when the throttle opening changes the most rapidly within a cycle is at the end of the cycle, at which point the throttle opening changes by 10 degrees per second. This value is then taken as the rate of change of throttle opening within the cycle. -1 The data is from the previous period, and Ts represents the period time.

[0052] After obtaining the throttle opening and throttle opening change rate within a cycle, the throttle opening can be compared with an opening threshold (Pa). The opening threshold can be a preset empirical value used to determine whether the throttle opening in the current cycle is too large. Additionally, the throttle opening change rate can be compared with a change rate threshold (Ga) to determine whether the rate of change of the throttle opening in the current cycle is too fast. If the throttle opening is too large and the throttle opening change rate is too fast, it indicates that the driver is performing a strong acceleration action. In this case, the dynamic flag can be set to the set state; otherwise, the dynamic flag is set to the reset state. Alternatively, if the throttle opening is too large and the throttle opening change rate is too fast, the dynamic flag is set to the set state; if the throttle opening is less than the threshold Pb or the timer duration reaches the duration T1, the dynamic flag is reset to the reset state. In other cases, the dynamic flag can remain unchanged, maintaining its current state.

[0053] When the dynamic flag is set, the initial speed compensation value is a preset value. This means that a certain amount of speed compensation is applied to the initial speed limit, making it larger or smaller to meet the user's current acceleration or deceleration needs. If the dynamic flag is reset, it indicates that the vehicle is in a stable driving state. In this case, no speed compensation is required, so the initial speed compensation value can be zero.

[0054] This application determines the state of the dynamic flag position based on the throttle opening and the rate of change of the throttle opening, and further determines the magnitude of the initial vehicle speed compensation value. Thus, the initial vehicle speed compensation value is obtained based on the driver's acceleration and deceleration intentions, which makes the final calculated target speed limit value more accurate.

[0055] For example, when the throttle opening is greater than the opening threshold and the rate of change of the throttle opening is greater than the rate of change threshold, after setting the state of the dynamic flag bit to the set state, the above method further includes: starting a timer; when the timer's duration exceeds a preset duration, setting the state of the dynamic flag bit to the reset state.

[0056] The example above illustrates that if the throttle opening is greater than a threshold and the rate of change of the throttle opening is greater than a threshold, the dynamic flag is set to the "set" state; otherwise, it is reset. This allows the initial vehicle speed compensation value to be determined based on the driver's acceleration or deceleration intentions. Continuing with... Figure 4 For example, if both the throttle opening and the rate of change of the throttle opening meet the requirements, after setting the state of the dynamic flag to the set state, a timer should be started to constrain the user's acceleration or deceleration state by timing the timer.

[0057] After the timer exceeds the preset duration (T1), the dynamic flag is reset. This strategy aims to prevent the dynamic flag from remaining in the set state for an extended period, resulting in a non-zero initial speed compensation value and an excessively large final calculated target speed limit, thus failing to achieve accurate speed limiting.

[0058] For example, the preset duration and preset value are determined based on the vehicle's overtaking distance.

[0059] In the above process, to ensure accurate initial speed compensation values, strategies were implemented to determine the initial speed compensation value based on throttle opening and its rate of change. Additionally, the dynamic marker state was adjusted by comparing the timing duration with a preset duration. The preset duration and preset value involved in this process can be determined based on the vehicle's overtaking distance. The overtaking distance can be the distance from the vehicle in front during overtaking, the safe overtaking distance, or the distance required for overtaking. A larger overtaking distance corresponds to a larger preset duration, or vice versa; the preset duration and preset value are inversely proportional to avoid situations where the target speed limit is too high for an extended period.

[0060] This application uses distance to determine the preset duration and preset value, which is more accurate than setting the preset duration and preset value based on experience.

[0061] For example, adjusting the initial vehicle speed compensation value for the current period using the initial vehicle speed compensation value from the historical period to obtain the target vehicle speed compensation value for the current period includes: when the initial vehicle speed compensation value for the current period is less than the initial vehicle speed compensation value for the previous period, determining a first compensation value difference between the initial vehicle speed compensation value for the previous period and the target vehicle speed compensation value for the previous period; adding a first threshold to the initial vehicle speed compensation value for the current period to obtain the target vehicle speed compensation value for the current period, wherein the first threshold is greater than or equal to the absolute value of the first compensation value difference; when the initial vehicle speed compensation value for the current period is greater than the initial vehicle speed compensation value for the previous period, determining a second compensation value difference between the initial vehicle speed compensation value for the previous period and the target vehicle speed compensation value for the previous period; and subtracting the second threshold from the initial vehicle speed compensation value for the current period to obtain the target vehicle speed compensation value for the current period, wherein the second threshold is greater than or equal to the absolute value of the second compensation value difference, and the second threshold is less than the first threshold.

[0062] In this example, after determining the initial speed compensation value using throttle opening and its change, further optimization can be performed to obtain a more accurate target speed compensation value. When determining the target speed compensation value, the initial speed compensation value can be compared with the initial speed compensation value of the previous cycle. Since the preset duration and preset value are determined based on the overtaking distance in this application, the preset value will change as the overtaking distance changes. Generally, when overtaking, the preset value decreases as the overtaking distance decreases, and increases as the overtaking distance increases after overtaking. Therefore, the initial speed compensation values ​​determined in different time cycles may not be the same. By comparing the magnitude of the initial speed compensation values, if the initial speed compensation value of the current cycle is greater than the initial speed compensation value of the previous cycle, the difference between the initial speed compensation value of the previous cycle and the target speed compensation value can be determined. Then, a first threshold greater than or equal to this difference is added to the initial speed compensation value of the current cycle. The purpose of this is to ensure that if the initial speed compensation value of the current cycle is greater than that of the previous cycle, it indicates that the overtaking distance is decreasing. The first threshold added to the initial speed compensation value of the current cycle must be greater than or equal to the value added in the previous cycle, thus compensating for more speed in the current cycle to reach the target speed limit and avoid the problem of being unable to overtake due to excessive speed limits. Conversely, if the initial speed compensation value of the current cycle is greater than that of the previous cycle, it indicates that the overtaking distance is increasing. In this case, a second threshold is reduced from the initial speed compensation value in the current cycle. This second threshold must be greater than or equal to the reduction in the initial speed compensation value in the previous cycle, thus providing a smaller target speed compensation value when the overtaking distance is increasing. The second threshold being less than the first threshold ensures that the rate of change of the target speed limit before overtaking is greater than the rate of change of the target speed limit after overtaking, making overtaking easier before and safer after.

[0063] This application obtains the target speed compensation value by adjusting the initial speed compensation value in different cycles, and determines a more accurate target speed compensation value by comparing the initial speed compensation value in each cycle. This improves the accuracy of the target speed limit value, and also improves the overtaking efficiency before overtaking and the overtaking safety after overtaking.

[0064] For example, limiting the vehicle speed in the next cycle based on the target speed limit includes: calculating the speed deviation based on the vehicle speed and the target speed limit; calculating the wheel end torque deviation based on the speed deviation; determining the current maximum wheel end torque based on the vehicle speed; adjusting the current maximum wheel end torque using the wheel end torque deviation to obtain the target maximum wheel end torque; and controlling the vehicle's maximum torque to be less than the target maximum wheel end torque.

[0065] In this example, once the target speed limit for each cycle is determined, the vehicle speed can be limited in the next cycle based on that target speed limit. Specifically, speed limiting can be achieved by constraining wheel-end torque. Figure 5 This diagram illustrates a method for speed limiting by controlling wheel-end torque. The vehicle's real-time speed is compared to the target speed limit to calculate the speed deviation (an initial speed deviation, which is filtered by a filter coefficient Tb to obtain the speed deviation; this deviation is then corrected by the correction coefficients in the correction coefficient table Vdev to arrive at the speed deviation of this application). The speed deviation represents the difference between the real-time speed and the target speed limit. The real-time speed corresponds to a current maximum wheel-end torque (the current maximum wheel-end torque is the current base torque). This current maximum wheel-end torque can be obtained by consulting the base torque table Nbas based on vehicle type, load, and gradient. Due to the aforementioned speed deviation between the real-time speed and the target speed limit, the wheel-end torque deviation is added to the current maximum wheel-end torque to obtain the target maximum wheel-end torque (wheel-end torque limit). Controlling the vehicle's wheel torque to not exceed the target maximum wheel-end torque limits the real-time speed from exceeding the target speed limit.

[0066] This application limits the vehicle speed by controlling the wheel-end torque, thereby ensuring that the vehicle's real-time speed does not exceed the target speed limit value within the cycle, thus improving the accuracy of vehicle speed limiting.

[0067] Let's illustrate this with an example of vehicle speed limiting. Taking a driver operating the vehicle over a 1-second time period as an example, the system first uses sensors to acquire data such as vehicle speed, longitudinal acceleration, remaining battery charge (SOC), and throttle opening during each time period. For the current period, the system compares the speed difference from the previous period with the current time period to obtain the vehicle speed-acceleration. The difference between this acceleration and the longitudinal acceleration is used as the initial value for the load parameters. This initial value is then processed by a first-order low-pass filter to obtain the final load parameters.

[0068] The initial speed limit for the current cycle is calculated using Formula 1 based on the load parameters and SOC data for the current cycle. Generally, the initial speed limit decreases as the load parameters increase and as the SOC of the power battery decreases.

[0069] The throttle opening in the current cycle is subtracted from the throttle opening in the previous cycle, and then compared with the cycle time to obtain the throttle opening change rate. The throttle opening is compared with the opening threshold, and the throttle opening change rate is compared with the change rate threshold to determine whether the initial vehicle speed compensation value is zero or a preset value. The preset value varies depending on the distance exceeded.

[0070] The initial speed compensation value of the current cycle is compared with the initial speed compensation value of the previous cycle. For example, if the initial speed compensation value of the current cycle is 10 (unit omitted, the unit is determined according to the actual situation, such as km / h), and the initial speed compensation value of the previous cycle is 8, then the initial speed compensation value of the current cycle is greater than the initial speed compensation value of the previous cycle. The first threshold for increasing the initial speed compensation value of the current cycle must be greater than or equal to the increase in the initial speed compensation value of the previous cycle. For example, if the initial speed compensation value of the previous cycle increased by 3 to obtain the target speed compensation value, then the initial speed compensation value of the current cycle must increase by a value greater than or equal to 3 to obtain the target speed compensation value. For example, the first threshold is 4. If the initial speed compensation value of the current cycle is less than the initial speed compensation value of the previous cycle, then if the initial speed compensation value of the previous cycle decreased by 2, then the second threshold for decreasing the initial speed compensation value in the current time cycle must be greater than or equal to 2. For example, the second threshold is 3. Furthermore, the second threshold must be less than the first threshold. If the initial velocity compensation value of the previous cycle decreased by 5, then the second threshold must be greater than or equal to 5 and less than 4. In this case, the second threshold cannot be selected. Therefore, we can first ensure that the second threshold is less than the first threshold to determine the second threshold.

[0071] The initial speed compensation value is compensated for by either the first or second threshold to obtain the target speed compensation value. The target speed compensation value is then used to compensate for the initial speed limit value to obtain the target speed limit value.

[0072] The calculated target speed limit value is the target speed limit value for the current cycle, used to set the speed limit for the next cycle. In the next cycle, the target speed limit value is subtracted from the real-time vehicle speed to obtain the speed deviation, which corresponds to the wheel-end torque deviation. Based on the vehicle's real-time speed, the torque table is consulted to obtain the current maximum wheel-end torque. The current maximum wheel-end torque is added to the wheel-end torque deviation to obtain the target maximum wheel-end torque. If the vehicle's wheel torque is greater than the target maximum wheel-end torque, the wheel torque is reduced to slow the vehicle down, achieving the speed limit. If the vehicle's wheel torque is not greater than the target maximum wheel-end torque, normal driving is allowed without a speed limit.

[0073] The following are embodiments of the apparatus of this application, which can be used to execute the embodiments of the method of this application.

[0074] Figure 6 This is a block diagram of a vehicle speed control device provided in an embodiment of this application. This device can be implemented as part or all of an electronic device through software, hardware, or a combination of both. Figure 6 As shown, the device includes: The first determining module 601 is used to determine the load parameters of the vehicle based on the vehicle speed and the vehicle longitudinal acceleration. The second determining module 602 is used to determine the initial speed limit value based on the load parameters and the remaining battery power of the vehicle. The third determining module 603 is used to determine the initial vehicle speed compensation value based on the vehicle's throttle opening and the rate of change of throttle opening. The adjustment module 604 is used to adjust the initial vehicle speed compensation value in the current period using the initial vehicle speed compensation value in the historical period, so as to obtain the target vehicle speed compensation value in the current period. The fourth determining module 605 is used to determine the target speed limit value for the next cycle based on the initial speed limit value and the target vehicle speed compensation value. Speed ​​limiting module 606 is used to limit the speed of a vehicle in the next cycle based on the target speed limit value.

[0075] The aforementioned device can be installed in a vehicle to limit its speed. When limiting the vehicle's speed, an initial speed limit value can be determined first. This initial speed limit value is determined based on load parameters and the remaining battery charge. Load parameters represent the vehicle's load condition and can be calculated based on the vehicle's speed and longitudinal acceleration. The remaining battery charge represents the battery's charge level and can be directly measured. Furthermore, a target speed compensation value can be determined. The target speed compensation value compensates for the initial speed limit value to arrive at the target speed limit. The target speed compensation value is determined by adjusting the initial speed compensation value. The initial speed compensation value can be determined based on the vehicle's throttle opening and its rate of change, representing the driver's acceleration and deceleration intentions.

[0076] In this application, when limiting the speed of a vehicle, instead of determining a target speed limit and then using that target speed limit indefinitely, a time period is divided. A target speed limit is determined for each period, and the vehicle speed is limited according to that target speed limit in the next period. For example, the time period can be 1 second, 3 seconds, 10 seconds, etc., but is not limited to these.

[0077] Figure 2This is a schematic diagram illustrating the determination of the target speed limit in this example. Taking the target speed limit within a time period as an example, in the process of determining the target speed limit, the vehicle's speed, longitudinal acceleration, remaining battery charge, throttle opening, and rate of change of throttle opening are acquired within the current period. The speed can be obtained through sensors and is the vehicle's real-time speed. The longitudinal acceleration is the acceleration component of the vehicle along the travel direction (i.e., the forward and backward direction), reflecting the rate of change of vehicle speed in the forward and backward direction. Based on the speed and longitudinal acceleration, load parameters can be calculated, which represent the vehicle's load condition. Specifically, vehicle speed acceleration can be calculated from speed, and the load parameters are calculated based on the difference between vehicle speed acceleration and longitudinal acceleration. The greater the difference between vehicle speed acceleration and longitudinal acceleration, the greater the vehicle's load.

[0078] The remaining battery power can be obtained by detecting the battery status, which can be expressed as a percentage or read as a numerical value. The remaining battery power directly reflects the amount of battery capacity. Based on the load parameters and the remaining battery power, the initial speed limit value is determined.

[0079] The initial speed limit is an intermediate value obtained during the calculation process. While directly using the initial speed limit to limit the vehicle's speed can achieve the desired effect, it is not the optimal solution. In this application, a target speed compensation value can be calculated to adjust the initial speed limit, thus obtaining the target speed limit. The target speed compensation value is obtained by adjusting the initial speed compensation value. The initial speed compensation value can be calculated based on the throttle opening and the rate of change of throttle opening. Throttle opening refers to the angle at which the throttle is open compared to when it is not depressed. The greater the force applied when the throttle is depressed, the greater the throttle opening. A greater throttle opening results in more battery power, leading to a faster vehicle speed in the same gear. The rate of change of throttle opening refers to the rate of change of throttle opening per unit time. A larger rate of change of throttle opening indicates a faster change in throttle speed per unit time, which can be understood as the throttle being rapidly depressed or released.

[0080] After calculating the initial vehicle speed compensation value using the throttle opening and its rate of change, the initial speed compensation value is adjusted, such as through filtering or accuracy verification, to obtain the target speed compensation value. This target speed compensation value is then used to compensate for the initial speed limit, either by adding the two values ​​together, or by multiplying the target speed compensation value by a weight and then adding it to the initial speed limit value, to obtain the target speed limit. The target speed limit value is then used to limit the vehicle's speed.

[0081] In this application, a target speed limit can be calculated for each time period, and the speed limit can be implemented in the next period. Alternatively, in another approach, data can be acquired once or multiple times at the beginning of the period to calculate the target speed limit for that period, and the speed limit can be implemented within that period.

[0082] This application determines the vehicle's load parameters based on its speed and longitudinal acceleration; determines the initial speed limit based on the load parameters and the vehicle's remaining battery power; determines the initial speed compensation value based on the throttle opening and its rate of change; adjusts the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain the target speed compensation value for the current period; determines the target speed limit for the next period based on the initial speed limit and the target speed compensation value; and limits the vehicle's speed based on the target speed limit in the next period. This method allows for the determination of the vehicle's load parameters based on its speed and longitudinal acceleration, representing its load status. Furthermore, it determines the initial speed limit based on the load parameters and the vehicle's remaining battery power, and further uses the throttle opening and its rate of change to determine the target speed compensation value, compensating for the initial speed limit to obtain the target speed limit value, which represents the vehicle's acceleration and deceleration. Using the target speed limit value for vehicle speed limiting improves the accuracy of vehicle speed limiting.

[0083] Other examples of this application can be found in the examples above, and will not be repeated here.

[0084] This application embodiment also provides a vehicle, including: a speed limiting module, used to determine the vehicle's load parameters based on the vehicle's speed and longitudinal acceleration; determine an initial speed limit value based on the load parameters and the vehicle's remaining battery charge; determine an initial speed compensation value based on the vehicle's throttle opening and throttle opening change rate; adjust the initial speed compensation value for the current period using the initial speed compensation values ​​from historical periods to obtain a target speed compensation value for the current period; determine a target speed limit value for the next period based on the initial speed limit value and the target speed compensation value; and an execution module, used to limit the vehicle's speed in the next period based on the target speed limit value.

[0085] The vehicle described in this application can be equipped with the speed control device of the aforementioned vehicle, or the speed limit module and the execution module can be used to simulate the function of the aforementioned device to achieve speed limit on the vehicle.

[0086] Other examples of this application can be found in the examples above, and will not be repeated here.

[0087] like Figure 7 As shown in the figure, this application embodiment provides a vehicle speed control device, including a processor 111, a communication interface 112, a memory 113, and a communication bus 114, wherein the processor 111, the communication interface 112, and the memory 113 communicate with each other through the communication bus 114. Memory 113 is used to store computer programs; In one embodiment of this application, when the processor 111 executes the program stored in the memory 113, it implements the vehicle speed control method provided in any of the foregoing method embodiments, including: acquiring historical data of the target vehicle, wherein the historical data includes at least the lateral offset data of the target vehicle on the road; inputting the historical data into a target prediction model, wherein the target prediction model is a model obtained by adjusting the original prediction model through total error, the total error being calculated based on the comparison error between the sample prediction trajectory and the sample true trajectory of the sample data after inputting sample data into the original prediction model and obtaining the sample prediction trajectory of the sample data, the comparison error including at least the lateral average displacement error, the longitudinal average displacement error, the lateral endpoint displacement error and the longitudinal endpoint displacement error, and the sample data including at least the lateral offset data of the sample vehicle on the road; and acquiring the target prediction trajectory of the target vehicle output by the target prediction model.

[0088] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the vehicle speed control method provided in any of the foregoing method embodiments.

[0089] The device embodiments described above are illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of the solution in this embodiment, depending on actual needs.

[0090] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented using software plus a general-purpose hardware platform, or of course, using hardware. Based on this understanding, the above technical solutions, in essence or the parts that contribute to the related technology, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments, or some parts of the embodiments.

[0091] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0092] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for controlling vehicle speed, characterized in that, include: The load parameters of the vehicle are determined based on the vehicle speed and longitudinal acceleration. The initial speed limit is determined based on the load parameters and the remaining battery power of the vehicle. The initial vehicle speed compensation value is determined based on the vehicle's throttle opening and throttle opening change rate. The initial vehicle speed compensation value for the current period is adjusted using the initial vehicle speed compensation value from the historical period to obtain the target vehicle speed compensation value for the current period. Based on the initial speed limit value and the target vehicle speed compensation value, determine the target speed limit value for the next cycle; The vehicle's speed will be limited in the next cycle based on the target speed limit value.

2. The method according to claim 1, characterized in that, The load parameters of the vehicle are determined based on the vehicle speed and longitudinal acceleration, including: The vehicle's speed and longitudinal acceleration are obtained through sensors in each cycle. The ratio of the change in vehicle speed to time is defined as the vehicle speed acceleration within the period; The difference between the vehicle's longitudinal acceleration and the vehicle speed acceleration within the cycle is determined as the initial value of the load parameter within the cycle; The load parameters for each cycle are initially subjected to a first-order low-pass filter to obtain the load parameters for each cycle.

3. The method according to claim 1, characterized in that, The initial speed limit is determined based on the load parameters and the remaining battery power of the vehicle, including: The initial speed limit value is calculated using the following formula: Where v is the initial speed limit, Po is the power of the vehicle's range extender at the optimal energy consumption operating point, and Pc is the power consumed by the entire vehicle. For the efficiency of the entire vehicle system, Where Ps is the battery output system efficiency, m is the vehicle's battery continuous discharge power, g is the vehicle weight, f is the gravitational acceleration, q is the load parameter, and a is the vehicle's required acceleration.

4. The method according to claim 1, characterized in that, Based on the vehicle's throttle opening and its rate of change, the initial vehicle speed compensation value is determined as follows: The throttle opening of the vehicle in each cycle is obtained through sensors; The difference between the throttle opening and the throttle opening of the previous cycle is compared with the cycle time to obtain the rate of change of the throttle opening in the current cycle. When the throttle opening is greater than the opening threshold and the rate of change of the throttle opening is greater than the rate of change threshold, the dynamic flag is set to the set state; otherwise, the dynamic flag is set to the reset state. When the dynamic flag is in the set state, the initial vehicle speed compensation value is a preset value; when the dynamic flag is in the reset state, the initial vehicle speed compensation value is zero.

5. The method according to claim 4, characterized in that, When the throttle opening is greater than the opening threshold and the rate of change of the throttle opening is greater than the rate of change threshold, after setting the dynamic flag to the set state, the method further includes: Start the timer; When the timer's duration exceeds the preset duration, the dynamic flag is set to a reset state.

6. The method according to claim 5, characterized in that, The preset duration and the preset value are determined based on the overtaking distance of the vehicle.

7. The method according to claim 1, characterized in that, The initial vehicle speed compensation value for the current period is adjusted using the initial vehicle speed compensation value from the historical period to obtain the target vehicle speed compensation value for the current period, including: When the initial vehicle speed compensation value of the current cycle is less than the initial vehicle speed compensation value of the previous cycle, a first compensation value difference between the initial vehicle speed compensation value of the previous cycle and the target vehicle speed compensation value of the previous cycle is determined; a first threshold is added to the initial vehicle speed compensation value in the current cycle to obtain the target vehicle speed compensation value in the current cycle, wherein the first threshold is greater than or equal to the absolute value of the first compensation value difference. When the initial vehicle speed compensation value of the current cycle is greater than the initial vehicle speed compensation value of the previous cycle, the difference between the initial vehicle speed compensation value of the previous cycle and the target vehicle speed compensation value of the previous cycle is determined; the initial vehicle speed compensation value in the current cycle is reduced by a second threshold to obtain the target vehicle speed compensation value in the current cycle, wherein the second threshold is greater than or equal to the absolute value of the difference between the second compensation values, and the second threshold is less than the first threshold.

8. The method according to claim 1, characterized in that, Limiting the vehicle's speed in the next cycle based on the target speed limit includes: Calculate the speed deviation based on the vehicle's speed and the target speed limit; Calculate the wheel end torque deviation based on the speed deviation; Based on the vehicle speed, determine the current maximum wheel-end torque of the vehicle; The current maximum wheel end torque is adjusted using the wheel end torque deviation to obtain the target maximum wheel end torque; The maximum torque of the vehicle is controlled to be less than the target maximum wheel-end torque.

9. A vehicle speed control device, characterized in that, include: The first determining module is used to determine the load parameters of the vehicle based on the vehicle speed and the vehicle longitudinal acceleration. The second determining module is used to determine the initial speed limit value based on the load parameters and the remaining battery power of the vehicle; The third determining module is used to determine the initial vehicle speed compensation value based on the throttle opening and the rate of change of the throttle opening of the vehicle. The adjustment module is used to adjust the initial vehicle speed compensation value in the current period using the initial vehicle speed compensation value in the historical period, so as to obtain the target vehicle speed compensation value in the current period. The fourth determining module is used to determine the target speed limit value in the next cycle based on the initial speed limit value and the target vehicle speed compensation value; The speed limiting module is used to limit the speed of the vehicle in the next cycle according to the target speed limit value.

10. A vehicle, characterized in that, include: The speed limiting module is used to determine the load parameters of the vehicle based on the vehicle speed and the vehicle's longitudinal acceleration. Based on the load parameters and the remaining battery power of the vehicle, an initial speed limit is determined; based on the throttle opening and the rate of change of the throttle opening, an initial vehicle speed compensation value is determined; the initial vehicle speed compensation value for the current period is adjusted using the initial vehicle speed compensation values ​​from the historical period to obtain the target vehicle speed compensation value for the current period; based on the initial speed limit and the target vehicle speed compensation value, the target speed limit for the next period is determined. An execution module is used to limit the speed of the vehicle in the next cycle according to the target speed limit value.

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