An anti-skid control method, device, equipment and medium based on an electromechanical brake clamp

Abstract

The application discloses an anti-skid control method and device based on an electromechanical brake clamp, equipment and a medium, and relates to the technical field of vehicle control. The method comprises the following steps: determining the sliding state parameters of each axle in the rail vehicle according to the axle speed and the vehicle speed of each axle; determining the target brake force adjustment rate of the corresponding axle based on the sliding state parameters; the target brake force adjustment rate represents the change amount of the electromechanical brake force of the corresponding axle in a unit time; taking the actual brake force of the corresponding axle as the starting point and taking the brake force change amount in a unit time after smoothing as the slope, a target brake force change curve of the corresponding axle in a preset time period is generated. According to the target brake force change curve, the electromechanical brake clamp of the corresponding axle is controlled to adjust the brake force, and the anti-skid control of the corresponding axle is realized according to the adjusted brake force. It can be seen that the electromechanical brake force can be flexibly adjusted according to the sliding state of the vehicle, thereby improving the anti-skid control effect of the vehicle and improving the riding comfort.

Description

Technical Field

[0001] This invention relates to the field of vehicle control technology, and in particular to an anti-skid control method, device, equipment and medium based on electromechanical brake calipers. Background Technology

[0002] With the development of vehicle braking technology, electromechanical braking systems are gradually being applied to vehicle braking control. Electromechanical braking systems mainly apply braking force by driving brake calipers with a motor. They have advantages such as fast response speed, high control precision, and relatively simple structure, and can provide a good hardware foundation for vehicle anti-skid control.

[0003] However, during vehicle braking, if the adhesion between the wheel and rail deteriorates or the braking force is excessive, the wheels may slip. To suppress wheel slippage, existing anti-slip control schemes typically adjust the braking force. However, the adjustment process for braking force in existing schemes is usually relatively fixed, making it difficult to adapt to changes in the vehicle's slippage state and affecting the effectiveness of anti-slip control. Furthermore, if the change in braking force is too sudden, it can easily cause longitudinal impact on the vehicle, thus affecting ride comfort. Therefore, there is a need for an anti-slip control method that can improve the effectiveness of anti-slip control and make the changes in braking force smoother. Summary of the Invention

[0004] In view of this, the purpose of this invention is to provide an anti-skid control method, device, equipment, and medium based on electromechanical brake calipers, which can flexibly adjust the electromechanical braking force according to the vehicle's skidding state, thereby improving the vehicle's anti-skid control effect and enhancing ride comfort. The specific solution is as follows: In a first aspect, this application discloses an anti-slip control method based on an electromechanical brake caliper, comprising: Obtain the axle speed of each axle in the rail vehicle; The vehicle speed of the rail vehicle is determined based on the axle speed, and the sliding state parameters of the corresponding axle are determined based on the axle speed and the vehicle speed of each axle. The target braking force adjustment rate for the corresponding axle is determined based on the coasting state parameters; the target braking force adjustment rate is used to characterize the change in electromechanical braking force of the corresponding axle per unit time. The target braking force adjustment rate is smoothed by filtering to obtain a smoothed braking force adjustment rate. The change in braking force per unit time is determined based on the smoothed braking force adjustment rate. Taking the actual braking force of the corresponding axle as the starting point and the change in braking force per unit time as the slope, a target braking force change curve of the corresponding axle within a preset time period is generated. The electromechanical brake calipers of the corresponding axle are controlled to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle based on the adjusted braking force.

[0005] Optionally, determining the slip state parameters of the corresponding axle based on the axle speed and the vehicle speed includes: The difference between the vehicle speed and the speed of the corresponding axle is determined as the speed difference of the corresponding axle. The axle velocity of the corresponding axle is differentially processed, and the differential processing result is filtered to obtain the axle acceleration of the corresponding axle. The ratio of the speed difference of the corresponding axle to the vehicle speed is determined as the slip ratio of the corresponding axle. The speed difference, axle acceleration, and slip ratio of the corresponding axle are determined as the slip state parameters of the corresponding axle.

[0006] Optionally, determining the target braking force adjustment rate for the corresponding axle based on the coasting state parameters includes: Based on the coasting state parameters of each axle, the coasting state of each axle is determined; wherein, the coasting state includes normal state, coasting aggravation state, coasting maintenance state and coasting recovery state; The initial braking force adjustment rate of the corresponding axle is determined based on the coasting state parameters of the corresponding axle, and the number of axles in the coasting aggravation state or the coasting holding state is counted. If the number of axles is less than two, it is determined that multi-axle cooperative control has not been triggered, and the initial braking force adjustment rate of the corresponding axle is determined as the target braking force adjustment rate of the corresponding axle. When there are at least two axles, it is determined that multi-axle cooperative control is triggered, and the initial braking force adjustment rate of the axle in the coasting aggravation state or the coasting holding state is processed based on the multi-axle cooperative strategy in order to obtain the target braking force adjustment rate of the corresponding axle.

[0007] Optionally, the process of adjusting the initial braking force adjustment rate of the axle in the coasting aggravation state or the coasting hold state based on the multi-axle cooperative strategy to obtain the target braking force adjustment rate of the corresponding axle includes: A reference axle is determined from the axles that are in the coasting acceleration state or the coasting hold state; The initial braking force adjustment rate of the reference axis is corrected, and the corrected braking force adjustment rate is determined as the target braking force adjustment rate of the reference axis. The initial braking force adjustment rate of the axle other than the reference axle, which is in the state of increased coasting or the state of coasting hold, is determined as the target braking force adjustment rate of the corresponding axle.

[0008] Optionally, determining the initial braking force adjustment rate of the corresponding axle based on the coasting state parameters of the corresponding axle includes: If the corresponding axle meets the first condition, the initial braking force adjustment rate is set to the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper; wherein, the first condition is that the speed difference of the corresponding axle is greater than a preset speed difference threshold, and the axle acceleration is less than a preset axle acceleration threshold. If the corresponding axle meets the second condition, the initial braking force adjustment rate is set to a negative value, and the absolute value of the initial braking force adjustment rate is positively correlated with the absolute value of the speed difference and the absolute value of the axle acceleration of the corresponding axle; wherein, the second condition includes: the speed difference of the corresponding axle is within a preset speed difference range, the axle acceleration is negative, and the first condition is not met; the preset speed difference range is set according to the vehicle operating state and anti-skid control requirements; If the corresponding axle meets the third condition, the initial braking force adjustment rate is set to a positive value, and the magnitude of the initial braking force adjustment rate is positively correlated with the axle acceleration of the corresponding axle and the rate of decrease of the speed difference; wherein, the third condition is that the axle acceleration of the corresponding axle changes from a negative value to a positive value or is within a preset positive value range, and the rate of decrease of the speed difference is the amount by which the speed difference of the corresponding axle decreases per unit time.

[0009] Optionally, correcting the initial braking force adjustment rate of the reference axis includes: If the initial braking force adjustment rate of the reference axis is positive, then the initial braking force adjustment rate is multiplied by a preset correction coefficient to obtain the corrected braking force adjustment rate; wherein the preset correction coefficient is greater than or equal to 1. If the initial braking force adjustment rate of the reference axis is negative, then the initial braking force adjustment rate is triggered to change from negative to zero or positive, thus obtaining the corrected braking force adjustment rate.

[0010] Optionally, the step of controlling the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve includes: Obtain the actual clamping force fed back by the electromechanical brake caliper of the corresponding axle; The actual clamping force is compared with the target clamping force corresponding to the target braking force change curve to obtain the clamping force deviation. The drive current of the drive motor in the electromechanical brake caliper is adjusted according to the clamping force deviation so that the actual clamping force tracks the target clamping force.

[0011] Secondly, this application discloses an anti-slip control device based on an electromechanical brake caliper, comprising: The axle speed acquisition module is used to acquire the axle speed of each axle in the rail vehicle; The state parameter determination module is used to determine the vehicle speed of the rail vehicle based on the axle speed, and to determine the sliding state parameters of the corresponding axle based on the axle speed and the vehicle speed of each axle. The adjustment rate determination module is used to determine the target braking force adjustment rate of the corresponding axle based on the coasting state parameters; the target braking force adjustment rate is used to characterize the change in the electromechanical braking force of the corresponding axle per unit time. The braking force change curve generation module is used to perform smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate. Based on the smoothed braking force adjustment rate, the amount of braking force change per unit time after smoothing is determined. Taking the actual braking force of the corresponding axle as the starting point and the amount of braking force change per unit time after smoothing as the slope, the target braking force change curve of the corresponding axle within a preset time period is generated. The axle anti-slip control module is used to control the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle based on the adjusted braking force.

[0012] Thirdly, this application discloses an electronic device, including: Memory, used to store computer programs; A processor is used to execute the computer program to implement the aforementioned anti-slip control method for electromechanical brake calipers.

[0013] Fourthly, this application discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the aforementioned anti-slip control method based on electromechanical brake calipers.

[0014] As can be seen, this application provides an anti-slip control method based on electromechanical brake calipers, which involves acquiring the axle speed of each axle in a rail vehicle; determining the vehicle speed based on the axle speed, and determining the corresponding axle's slip state parameters based on the axle speed and the vehicle speed; determining the target braking force adjustment rate for the corresponding axle based on the slip state parameters; the target braking force adjustment rate characterizing the change in electromechanical braking force of the corresponding axle per unit time; performing smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate; determining the smoothed change in braking force per unit time based on the smoothed braking force adjustment rate; generating a target braking force change curve for the corresponding axle within a preset time period, using the actual braking force of the corresponding axle as the starting point and the smoothed change in braking force per unit time as the slope; and controlling the electromechanical brake calipers of the corresponding axle to adjust the braking force according to the target braking force change curve, thereby achieving anti-slip control of the corresponding axle based on the adjusted braking force. Therefore, this application obtains the axle speed of each axle in the rail vehicle and determines the vehicle speed based on the axle speed to determine the coasting state parameters of the corresponding axle. On this basis, instead of directly adjusting the electromechanical braking force according to a fixed amplitude or fixed rate, it first determines the target braking force adjustment rate of the corresponding axle based on the coasting state parameters, then performs smoothing filtering on the target braking force adjustment rate, and determines the change in braking force per unit time based on the smoothed braking force adjustment rate. Taking the actual braking force of the corresponding axle as the starting point and the change in braking force per unit time as the slope, a target braking force change curve of the corresponding axle within a preset time period is generated, thereby controlling the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve. Therefore, this application enables the change process of electromechanical braking force to match the sliding state parameters of the corresponding axle, reducing the risk of untimely or inaccurate braking force adjustment due to a fixed braking force adjustment method; at the same time, by constraining the change process of braking force within a unit time by the target braking force change curve, it can reduce the longitudinal impact of sudden braking force changes on the vehicle, improve the continuity and smoothness of the braking force adjustment process, and thus improve the anti-skid control effect of rail vehicles. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0016] Figure 1 This is a flowchart of an anti-slip control method based on an electromechanical brake caliper disclosed in this application; Figure 2 This is a schematic diagram of an anti-slip control system architecture disclosed in this application; Figure 3 This is a schematic diagram of an anti-slip control device based on an electromechanical brake caliper disclosed in this application; Figure 4 This is a structural diagram of an electronic device disclosed in this application. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] To suppress wheel slippage, existing anti-skid control systems typically adjust the braking force. However, the adjustment process for braking force in existing systems is usually quite fixed, making it difficult to adapt to changes in the vehicle's slippage state and affecting the effectiveness of anti-skid control. Furthermore, if the braking force changes too suddenly, it can easily cause longitudinal impact on the vehicle, thus affecting ride comfort.

[0019] Therefore, this application proposes an anti-skid control scheme based on electromechanical brake calipers, which can flexibly adjust the electromechanical braking force according to the vehicle's skidding state, thereby improving the vehicle's anti-skid control effect and enhancing ride comfort.

[0020] This application discloses an anti-slip control method based on an electromechanical brake caliper. See [link to relevant documentation]. Figure 1 As shown, the method includes: Step S11: Obtain the axle speed of each axle in the rail vehicle.

[0021] In this embodiment, the rail vehicle includes multiple axles, each of which can be equipped with an axle-end speed sensor. The axle-end speed sensor is used to collect the original rotational speed pulse signal of the corresponding axle. The braking control unit can receive the original rotational speed pulse signal collected by each axle-end speed sensor to obtain the speed acquisition data of each axle. After receiving the original rotational speed pulse signal corresponding to each axle, the braking control unit can calculate the instantaneous angular velocity of the corresponding axle based on the pulse frequency of the original rotational speed pulse signal, and convert the instantaneous angular velocity of the corresponding axle into the linear velocity of the corresponding axle. This linear velocity can be used as the axle velocity of the corresponding axle. To distinguish different axles, the axle velocity of the i-th axle can be denoted as V_axle[i], where i represents the axle position. Through the above method, the braking control unit can obtain the axle velocity corresponding to each axle in the rail vehicle. The axle velocity of each axle can be used to subsequently determine the vehicle speed of the rail vehicle and to subsequently determine the coasting state parameters of the corresponding axle.

[0022] Step S12: Determine the vehicle speed of the rail vehicle based on the axle speed, and determine the sliding state parameters of the corresponding axle based on the axle speed and the vehicle speed of each axle.

[0023] In this embodiment, after acquiring the axle speeds of each axle in the rail vehicle, the braking control unit can determine the vehicle speed based on these axle speeds. Specifically, a multi-axle speed fusion algorithm can be used to process the axle speeds to obtain the vehicle speed. For example, the multi-axle speed fusion algorithm may include taking the maximum value among the axle speeds of each axle, or performing a weighted average of the axle speeds. The obtained vehicle speed can be used to characterize the current operating reference speed of the rail vehicle. For ease of explanation, the vehicle speed can be denoted as V_ref.

[0024] After obtaining the vehicle speed, the slip state parameters of the corresponding axle are determined based on the axle speed of each axle and the vehicle speed. Specifically, for any axle, the difference between the vehicle speed and the axle speed can be defined as the speed difference of that axle. That is, if the axle speed of the i-th axle is V_axle[i] and the vehicle speed is V_ref, then the speed difference of the i-th axle can be expressed as ΔV[i] = V_ref - V_axle[i]. This speed difference reflects the slip amount of the corresponding axle. Further, the axle speed of the corresponding axle is differentially processed, and the corresponding differential processing result is filtered to obtain the axle acceleration of the corresponding axle. For ease of explanation, the axle acceleration of the i-th axle can be denoted as β[i]. In addition, the slip ratio of the corresponding axle can be determined based on the speed difference of the corresponding axle and the vehicle speed. Specifically, the ratio of the speed difference of the corresponding axle to the vehicle speed can be defined as the slip ratio of the corresponding axle. If the speed difference of the i-th axle is ΔV[i] and the vehicle speed is V_ref, then the slip ratio of the i-th axle can be expressed as λ[i] = ΔV[i] / V_ref. This slip ratio is used for subsequent adhesion control or slip state determination.

[0025] Based on this, for each axle, the speed difference, axle acceleration, and slip ratio of the corresponding axle are determined as the slip state parameters of the corresponding axle. Subsequently, the target braking force adjustment rate of the corresponding axle can be determined based on the slip state parameters of the corresponding axle, so that the electromechanical braking force adjustment process of the corresponding axle is adapted to the slip state of the axle.

[0026] Step S13: Determine the target braking force adjustment rate of the corresponding axle based on the coasting state parameters; the target braking force adjustment rate is used to characterize the change in electromechanical braking force of the corresponding axle per unit time.

[0027] In this embodiment, after determining the coasting state parameters corresponding to each axle, the coasting state of each axle can be determined based on these parameters. The coasting state parameters include the speed difference, axle acceleration, and slip ratio of the corresponding axle. This embodiment can determine the coasting state based on the speed difference and axle acceleration, which can include a normal state, a coasting acceleration state, a coasting holding state, and a coasting recovery state. In a specific implementation, the current coasting state of the corresponding axle can be determined based on the comparison between the speed difference and axle acceleration of the corresponding axle and preset thresholds. The preset thresholds can include a preset speed difference threshold for comparison with the speed difference and a preset axle acceleration threshold for comparison with the axle acceleration. The preset speed difference threshold can serve as a comparison benchmark for determining whether the speed difference of the corresponding axle has reached the corresponding degree of coasting, and the preset axle acceleration threshold can serve as a comparison benchmark for determining whether the axle acceleration of the corresponding axle has reached the corresponding degree of change. The specific values ​​of these thresholds can be preset according to actual vehicle control requirements, and this application does not limit them.

[0028] After determining the coasting state of the corresponding axle, the initial braking force adjustment rate of the corresponding axle can be determined based on the coasting state parameters. This initial braking force adjustment rate can be used to characterize the direction and speed of the electromechanical braking force adjustment of the corresponding axle per unit time before multi-axle coordinated processing. The initial braking force adjustment rate can be negative, zero, or positive. When the initial braking force adjustment rate is negative, it indicates that the electromechanical braking force of the corresponding axle needs to be reduced; when the initial braking force adjustment rate is positive, it indicates that the electromechanical braking force of the corresponding axle needs to be increased or restored; when the initial braking force adjustment rate is zero, it indicates that the electromechanical braking force of the corresponding axle can remain unchanged.

[0029] In the first embodiment, if the corresponding axle meets the first condition, the initial braking force adjustment rate of the corresponding axle is set to the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper. The first condition can be: the speed difference between the corresponding axles is greater than a preset speed difference threshold, and the axle acceleration of the corresponding axle is less than a preset axle acceleration threshold. That is, when the speed difference between the corresponding axles exceeds the corresponding threshold and the axle acceleration is lower than the corresponding threshold, it indicates that the axle speed of the corresponding axle deviates significantly from the vehicle speed, and the axle speed still has a decreasing trend. If a large electromechanical braking force is maintained at this time, it may lead to further aggravation of skidding. Therefore, the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper can be used to reduce the electromechanical braking force of the corresponding axle to quickly reduce the braking force of the axle. The negative braking force adjustment rate indicates that the braking force changes in the decreasing direction.

[0030] In the second embodiment, if the corresponding axle meets the second condition, the initial braking force adjustment rate of the corresponding axle is set to a negative value, and the absolute value of this initial braking force adjustment rate is positively correlated with the absolute value of the speed difference and the absolute value of the axle acceleration of the corresponding axle. The second condition may include: the speed difference of the corresponding axle is within a preset speed difference range, the axle acceleration of the corresponding axle is negative, and the corresponding axle does not meet the first condition. The preset speed difference range can be pre-set according to the vehicle's operating state and anti-skid control requirements, and is used to characterize situations where the speed difference of the corresponding axle is large. When the speed difference of the corresponding axle is within the preset speed difference range, the axle acceleration is negative, and the first condition is not met, it is determined that the corresponding axle meets the second condition. That is, when the speed difference of the corresponding axle is within the preset speed difference range, the axle acceleration is negative, and the level corresponding to the first condition is not reached, it indicates that the corresponding axle has a skidding tendency, but has not yet reached the level requiring processing with the maximum negative braking force adjustment rate. At this point, the initial braking force adjustment rate can be set to a negative value to reduce the electromechanical braking force of the corresponding axle. Furthermore, the larger the absolute value of the speed difference and the axle acceleration, the larger the absolute value of the initial braking force adjustment rate can be, thus matching the rate of reduction of the electromechanical braking force with the sliding state parameters of the corresponding axle. The absolute value of the initial braking force adjustment rate indicates how quickly the electromechanical braking force changes in the decreasing direction.

[0031] In the third embodiment, if the corresponding axle meets the third condition, the initial braking force adjustment rate of the corresponding axle is set to a positive value. The magnitude of this initial braking force adjustment rate is positively correlated with the axle's axial acceleration and the rate of decrease in the speed difference, where the rate of decrease in the speed difference is the amount by which the speed difference of the corresponding axle decreases per unit time. The third condition can be: the axle's axial acceleration changes from negative to positive, or the axle's axial acceleration is within a preset positive value range. That is, when the axle's axial acceleration changes from negative to positive or is within a preset positive value range, it indicates that the speed decrease trend of the corresponding axle has weakened or the axle speed has a recovery trend. At this time, the initial braking force adjustment rate can be set to a positive value to gradually increase or restore the electromechanical braking force of the corresponding axle. Furthermore, the greater the axial acceleration and the greater the rate of decrease in the speed difference, the greater the initial braking force adjustment rate can be, thereby matching the recovery process of the electromechanical braking force with the recovery of the corresponding axle's sliding motion. The positive braking force adjustment rate indicates that the braking force changes in the direction of increase. The preset positive value range can be determined based on vehicle control requirements, anti-skid control requirements, etc., and is not limited here.

[0032] After obtaining the initial braking force adjustment rate for each axle, the number of axles in either a coasting acceleration or coasting hold state is counted. On one hand, if fewer than two axles are in either a coasting acceleration or coasting hold state, it can be determined that multi-axle cooperative control has not been triggered. In the absence of multi-axle cooperative control, the initial braking force adjustment rate of the corresponding axle is determined as the target braking force adjustment rate for that axle, so that a target braking force change curve for the corresponding axle can be generated subsequently based on this target braking force adjustment rate. On the other hand, if at least two axles are in either a coasting acceleration or coasting hold state, it can be determined that multi-axle cooperative control has been triggered. In the case of triggering multi-axle cooperative control, based on the multi-axle cooperative strategy, the initial braking force adjustment rate of the axles in either a coasting acceleration or coasting hold state is processed to obtain the target braking force adjustment rate for the corresponding axle. Specifically, a reference axle can be determined from the axles that are in a state of increased coasting or coasting hold, and the initial braking force adjustment rate of the reference axle can be corrected. The corrected braking force adjustment rate can then be determined as the target braking force adjustment rate of the reference axle. For axles other than the reference axle that are in a state of increased coasting or coasting hold, their initial braking force adjustment rate can be determined as the target braking force adjustment rate of the corresponding axle.

[0033] In this embodiment, the reference axle can be determined based on the recovery trend, instantaneous speed, or axle load information of each sliding axle. For example, the recovery trend of each sliding axle can be determined based on the axle acceleration within a preset time window, and the axle with the better recovery trend can be selected as the reference axle; if the recovery trends of multiple axles are similar, the axle with the higher current axle speed can be selected as the reference axle; or, the axle with the larger load can be selected as the reference axle by combining axle load information.

[0034] When correcting the initial braking force adjustment rate of the reference axle, if the initial braking force adjustment rate of the reference axle is positive, it can be multiplied by a preset correction coefficient to obtain the corrected braking force adjustment rate, where the preset correction coefficient is greater than or equal to 1. If the initial braking force adjustment rate of the reference axle is negative, it can be corrected to zero or a positive value to obtain the corrected braking force adjustment rate. The positive value indicates that the electromechanical braking force of the corresponding axle needs to be increased or restored. Its specific value can be determined based on the rate of decrease of the axle acceleration and speed difference of the corresponding axle, for example, using a pre-calibrated mapping relationship, a lookup table, or a control algorithm. It should be noted that since the reference axle can be determined from multiple sliding axles based on the recovery trend, instantaneous speed, or axle load information, it has a higher recovery potential compared to other sliding axles. Therefore, prioritizing the braking force adjustment of the reference axle helps it recover to a stable state first, thereby shortening the overall vehicle sliding recovery time under multi-axle sliding conditions and improving the anti-skid control effect under multi-axle sliding conditions.

[0035] Step S14: Perform smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate. Determine the change in braking force per unit time based on the smoothed braking force adjustment rate. Using the actual braking force of the corresponding axle as the starting point and the change in braking force per unit time as the slope, generate the target braking force change curve of the corresponding axle within a preset time period.

[0036] After determining the target braking force adjustment rate for the corresponding axle, the change in braking force of the corresponding axle per unit time is determined according to this target braking force adjustment rate. The target braking force adjustment rate can be the initial braking force adjustment rate of the corresponding axle, or a braking force adjustment rate obtained after multi-axle coordinated processing of the initial braking force adjustment rate of the corresponding axle. The target braking force adjustment rate is used to characterize the direction and speed of change of the electromechanical braking force of the corresponding axle. Specifically, when the target braking force adjustment rate is positive, it indicates that the electromechanical braking force of the corresponding axle changes in an increasing direction; when the target braking force adjustment rate is negative, it indicates that the electromechanical braking force of the corresponding axle changes in a decreasing direction; when the target braking force adjustment rate is zero, it indicates that the electromechanical braking force of the corresponding axle remains unchanged.

[0037] It should be noted that, to avoid abrupt changes in the braking force command due to sudden shifts in the target braking force adjustment rate, a smoothing filter can be applied to the target braking force adjustment rate to obtain a smoothed rate. For example, a first-order hysteresis filter can be applied to the target braking force adjustment rate to obtain the smoothed rate. As can be seen, smoothing filtering reduces the impact of sudden shifts in the target braking force adjustment rate on the target braking force change curve, making the subsequently generated target braking force change curve more continuous, thereby improving the smoothness of the braking force adjustment process.

[0038] Furthermore, the smoothed braking force change per unit time is determined based on the smoothed braking force adjustment rate. Specifically, the smoothed braking force adjustment rate characterizes the direction and magnitude of change in the electromechanical braking force of the corresponding axle per unit time after smoothing. Therefore, the smoothed braking force adjustment rate can be used as the smoothed braking force change per unit time. If the smoothed braking force adjustment rate is positive, the smoothed braking force change per unit time indicates that the braking force changes in the direction of increase; if the smoothed braking force adjustment rate is negative, the smoothed braking force change per unit time indicates that the braking force changes in the direction of decrease; if the smoothed braking force adjustment rate is zero, the smoothed braking force change per unit time indicates that the braking force remains unchanged.

[0039] Furthermore, taking the actual braking force of the corresponding axle as the starting point and the smoothed change in braking force per unit time as the slope, a target braking force change curve for the corresponding axle within a preset time period is generated. For example, if the actual braking force of the corresponding axle is F_actual[i], the smoothed change in braking force per unit time is ΔF_smooth[i], and the time variable within the preset time period is τ, then the target braking force change curve can be expressed as: F_target[i] = F_actual[i] + ΔF_smooth[i] × τ, where τ belongs to the preset time period. In this way, the actual braking force can be used as the starting point of the target braking force change curve, and the smoothed change in braking force per unit time can be used to limit the change process of the target braking force over time, thereby generating the target braking force change curve for the corresponding axle within a preset time period.

[0040] As can be seen, the initial value of the target braking force variation curve is the current actual braking force of the corresponding axle. This ensures that the target braking force variation curve begins to change from the current actual braking force of the electromechanical brake caliper, preventing abrupt changes in the target braking force command relative to the current actual braking force. Simultaneously, the smoothed change in braking force per unit time is used as the slope of the target braking force variation curve, ensuring that the target braking force changes with time according to the corresponding direction and rate of change, thereby improving the continuity and smoothness of the braking force adjustment process.

[0041] Step S15: Control the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle according to the adjusted braking force.

[0042] In this embodiment, controlling the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve includes: acquiring the actual clamping force fed back by the electromechanical brake caliper of the corresponding axle; comparing the actual clamping force with the target clamping force corresponding to the target braking force change curve to obtain the clamping force deviation; and adjusting the drive current of the drive motor in the electromechanical brake caliper according to the clamping force deviation to make the actual clamping force track the target clamping force. Specifically, after generating the target braking force change curve of the corresponding axle, the brake control unit can determine the target braking force corresponding to the current control moment according to the target braking force change curve, and determine the corresponding target clamping force according to the target braking force. The target clamping force can be the clamping force expected to be achieved by the electromechanical brake caliper at the current control moment. Correspondingly, the actual clamping force fed back by the electromechanical brake caliper of the corresponding axle can be acquired. The actual clamping force can be the clamping force actually applied by the electromechanical brake caliper at the current control moment, which can be detected by the force sensor in the electromechanical brake caliper. By acquiring the actual clamping force, the current clamping force output of the electromechanical brake caliper can be obtained, providing a basis for subsequent adjustment of the drive current based on the difference between the actual clamping force and the target clamping force. After acquiring the actual clamping force, it can be compared with the target clamping force corresponding to the target braking force change curve to obtain the clamping force deviation. The clamping force deviation is used to represent the difference between the actual clamping force and the target clamping force. If the actual clamping force is less than the target clamping force, it indicates that the current clamping force output by the electromechanical brake caliper is insufficient; if the actual clamping force is greater than the target clamping force, it indicates that the current clamping force output by the electromechanical brake caliper is too large; if the difference between the actual clamping force and the target clamping force is small, it indicates that the current clamping force output by the electromechanical brake caliper is close to the target clamping force.

[0043] Based on this, this embodiment can adjust the drive current of the drive motor in the electromechanical brake caliper according to the clamping force deviation. Specifically, when the actual clamping force is less than the target clamping force, the drive current of the drive motor can be adjusted to increase the actual clamping force of the electromechanical brake caliper; when the actual clamping force is greater than the target clamping force, the drive current of the drive motor can be adjusted to decrease the actual clamping force of the electromechanical brake caliper; when the deviation between the actual clamping force and the target clamping force is small, the electromechanical brake caliper can maintain a corresponding clamping force output. Thus, the actual clamping force can track the target clamping force, thereby adjusting the actual braking force of the corresponding axle according to the target braking force change curve.

[0044] In summary, electromechanical brake calipers can adjust the drive current of the drive motor based on the deviation between the target clamping force and the actual clamping force, forming a force closed-loop control process with the clamping force as the feedback quantity. Therefore, the actual clamping force can increase, decrease, or remain constant according to changes in the target clamping force, allowing the actual braking force of the corresponding axle to be adjusted according to the target braking force variation curve. Since the target braking force variation curve is generated based on the sliding state parameters of the corresponding axle and the target braking force adjustment rate, adjusting the actual braking force of the corresponding axle according to this curve helps to match the braking force adjustment process with the sliding state of the corresponding axle, thereby facilitating anti-slip control of the corresponding axle.

[0045] To further explain the anti-slip control method based on electromechanical brake calipers described above, a detailed explanation is provided below with reference to a specific system architecture. (See also...) Figure 2 As shown, a rail vehicle may include an axle-end speed sensor, a train network / train control unit, a traction control unit, a braking control unit, a motor drive control unit, and multiple electromechanical brake calipers. Figure 2 Taking axle-end speed sensor 1 and axle-end speed sensor 2 as examples, each axle-end speed sensor is used to collect the speed acquisition signal of the corresponding axle and send it to the brake control unit. The train network / train control unit can send traction commands to the traction control unit and brake commands to the brake control unit. The traction control unit can exchange information with the brake control unit regarding the dynamic redistribution of braking force. The brake control unit can determine the coasting state based on the speed acquisition signal, and determine the target braking force adjustment rate through the coasting state judgment and decision module and the target braking force adjustment rate determination module, and then send a braking command or a force command with slope to the motor drive control unit. The motor drive control unit controls the drive motor in each electromechanical brake caliper to apply clamping force according to the command. The force sensor in each electromechanical brake caliper detects the actual clamping force and feeds it back to the brake control unit so that the brake control unit can adjust the braking force of the electromechanical brake caliper according to the actual clamping force feedback.

[0046] It should be noted that in this embodiment, the braking control unit can be an Electronic Brake Control Unit (EBCU); for motor vehicles, it can also be an Integrated Traction and Brake Control Unit (ITBCU) that integrates traction and braking control functions. Rail vehicles may also include a Traction Control Unit (TCU), a vehicle network, or a train control unit. The traction control unit can be used to control electric braking force, and the vehicle network or train control unit can be used to transmit control commands or status information between the braking control unit, the traction control unit, and other vehicle control devices. It should be noted that the aforementioned traction control unit, vehicle network, or train control unit can be optional cooperative control units, and whether they participate in anti-skid control can be determined based on the specific configuration of the vehicle's braking system; this application does not specifically limit this.

[0047] (1) Regarding signal acquisition and calculation of taxiing state parameters.

[0048] In this embodiment, the braking control unit can receive the axle-end speed sensor signals corresponding to each axle, and calculate the instantaneous angular velocity of the corresponding axle based on the pulse frequency of the original rotational speed pulse signal, and then convert the instantaneous angular velocity into the linear velocity of the corresponding axle. This linear velocity can be used as the axle velocity of the corresponding axle. For ease of explanation, the axle velocity of the i-th axle can be denoted as V_axle[i]. After obtaining the axle velocities of each axle, the braking control unit can use a multi-axle velocity fusion algorithm to determine the vehicle speed of the rail vehicle. The multi-axle velocity fusion algorithm may include taking the maximum value among the axle velocities of each axle, or performing a weighted average of the axle velocities of each axle, etc. The determined vehicle speed can be denoted as V_ref.

[0049] Furthermore, after obtaining the vehicle speed V_ref, the sliding state parameters corresponding to each axle can be determined. For the i-th axle, the difference between the vehicle speed V_ref and the axle speed V_axle[i] can be defined as the speed difference, i.e., ΔV[i] = V_ref - V_axle[i]. The speed difference ΔV[i] can reflect the amount of slippage of the corresponding axle relative to the vehicle speed. Further, the axle speed V_axle[i] can be differentially processed, and the result can be filtered to obtain the axle acceleration β[i], i.e., β[i] = d(V_axle[i]) / dt. The axle acceleration β[i] can reflect the speed change trend of the corresponding axle. Further, the slip ratio λ[i] can be determined based on the speed difference ΔV[i] and the vehicle speed V_ref, i.e., λ[i] = ΔV[i] / V_ref. The slip ratio λ[i] can be used for subsequent adhesion control or sliding state judgment.

[0050] (2) Regarding the judgment of gliding state and multi-axis collaborative decision-making.

[0051] After determining the speed difference, axle acceleration, and slip ratio for each axle, the brake control unit can determine the slip state of the corresponding axle based on the slip state parameters. Specifically, based on the comparison between the speed difference and axle acceleration and preset thresholds, each axle can be classified into a normal state, a slip aggravation state, a slip maintenance state, or a slip recovery state. The preset thresholds may include a preset speed difference threshold for comparison with the speed difference, and a preset axle acceleration threshold for comparison with the axle acceleration. These thresholds can be predetermined based on vehicle control requirements, anti-skid control requirements, and track test results.

[0052] After obtaining the coasting state of each axle, the number of axles in either the coasting acceleration state or coasting hold state can be counted. If the number of axles in either the coasting acceleration state or coasting hold state is less than two, it can be determined that multi-axle cooperative control has not been triggered. In the absence of multi-axle cooperative control, the initial braking force adjustment rate of the corresponding axle can be determined as the target braking force adjustment rate. If the number of axles in either the coasting acceleration state or coasting hold state is greater than or equal to two, it can be determined that multi-axle cooperative control has been triggered. In the case of multi-axle cooperative control, the brake control unit can determine the reference axle from the above axles and perform differentiated processing on the braking force adjustment process of multiple coasting axles based on the reference axle.

[0053] It should be noted that when determining the reference axle, it can be based on the recovery trend, instantaneous speed, or axle load information of each coasting axle. For example, the recovery trend of each coasting axle can be determined based on the axle acceleration within a preset time window, and the axle with the better recovery trend can be selected as the reference axle; if the recovery trends of multiple axles are similar, the axle with the higher current axle speed can be selected as the reference axle; alternatively, the axle with the larger load can be selected as the reference axle by combining the axle load information provided by the vehicle weighing system. In other words, the determined axle can be marked as the reference axle, and the remaining axles in the coasting acceleration state or coasting hold state can be marked as non-reference axles.

[0054] (3) Determination of the target braking force adjustment rate.

[0055] The brake control unit can determine the initial braking force adjustment rate for each sliding axle. The initial braking force adjustment rate for the i-th axle is denoted as K[i], with units of kN / s. The sign of K[i] indicates the direction of braking force adjustment, and the magnitude of K[i] indicates the rate of change of braking force. Based on the degree of sliding and its changing trend, as represented by the speed difference and axle acceleration, the brake control unit can divide the braking force adjustment process of the corresponding axle into an emergency unloading zone, a rapid unloading zone, and a fine adjustment / recovery zone. The emergency unloading zone corresponds to the first condition, the rapid unloading zone to the second condition, and the fine adjustment / recovery zone to the third condition.

[0056] First, within the emergency unloading zone, since the speed difference between the corresponding axles is greater than the preset speed difference threshold, and the axle acceleration is less than the preset axle acceleration threshold, it indicates that the axle speed of the corresponding axle deviates significantly from the vehicle speed, and the axle speed still shows a clear decreasing trend, posing a risk of rapid deterioration of the skidding. Therefore, the initial braking force adjustment rate of the corresponding axle can be set to the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper, so that the electromechanical braking force of the corresponding axle decreases at a larger rate, thereby suppressing further aggression of the skidding.

[0057] Secondly, within the rapid unloading zone, since the speed difference of the corresponding axle is within the preset speed difference range, the axle acceleration is negative and the first condition is not met, indicating that the corresponding axle already has a tendency to increase skidding, but has not yet reached the rapid deterioration level corresponding to the emergency unloading zone. Therefore, the initial braking force adjustment rate of the corresponding axle can be set to a negative value, and the absolute value of this initial braking force adjustment rate can be positively correlated with the absolute value of the speed difference and the absolute value of the axle acceleration. In this way, when the skidding trend is more obvious, the electromechanical braking force of the corresponding axle can be reduced at a faster rate; when the skidding trend is relatively weak, the electromechanical braking force of the corresponding axle can be reduced at a smaller rate, thereby matching the braking force reduction process with the degree of skidding intensification.

[0058] Finally, within the fine adjustment / recovery zone, since the axle acceleration of the corresponding axle changes from negative to positive, or falls within a preset positive range, it indicates that the decreasing speed trend of the corresponding axle has weakened, or that the axle speed has a recovery trend. Therefore, the initial braking force adjustment rate of the corresponding axle can be set to a positive value, and the magnitude of this initial braking force adjustment rate can be positively correlated with the axle acceleration and the rate of decrease in the speed difference. In this way, when the axle speed recovery trend is more obvious, the electromechanical braking force of the corresponding axle can recover at a faster rate; when the recovery trend is relatively weak, the electromechanical braking force of the corresponding axle can recover at a smaller rate, thereby reducing the risk of re-skimming due to excessively rapid braking force recovery.

[0059] In multi-axle cooperative control scenarios, for the axle designated as the reference axle, its initial braking force adjustment rate can be differentiated and corrected, and the corrected braking force adjustment rate can be determined as the target braking force adjustment rate for the reference axle. Specifically, if the initial braking force adjustment rate of the reference axle is positive, it can be multiplied by a preset correction coefficient to obtain the corrected braking force adjustment rate, where the preset correction coefficient is greater than or equal to 1. That is, when the reference axle is in the recovery phase, it can recover braking force with a larger positive braking force adjustment rate. If the initial braking force adjustment rate of the reference axle is negative, it can be corrected to zero or a positive value to obtain the corrected braking force adjustment rate. For sliding axles other than the reference axle, their initial braking force adjustment rate can be determined as the target braking force adjustment rate.

[0060] (4) The specific mapping method for the initial braking force adjustment rate.

[0061] In one alternative implementation, the initial braking force adjustment rate K[i] can be determined using a two-dimensional lookup table interpolation method. Specifically, a two-dimensional K-value database indexed by the speed difference ΔV and axle acceleration β can be established, which can be calibrated through bench tests or line tests. During actual control, the brake control unit can look up the table in real time based on the current speed difference ΔV[i] and axle acceleration β[i], and obtain the initial braking force adjustment rate K[i] of the corresponding axle through bilinear interpolation.

[0062] In another alternative implementation, the initial braking force adjustment rate K[i] can be determined using a proportional-derivative control method based on a simplified model. Specifically, the target slip ratio λ_target can be used as the setpoint, the slip ratio deviation e = λ_target - λ[i] can be calculated, and the initial braking force adjustment rate K[i] can be determined according to K[i] = Kp × e + Kd × de / dt. Kp is the proportional coefficient, Kd is the derivative coefficient, and de / dt is the rate of change of slip ratio deviation. The target slip ratio λ_target can be zero, or it can be determined according to the adhesion control requirements.

[0063] In another alternative implementation, the initial braking force adjustment rate K[i] can be determined through fuzzy logic reasoning. Specifically, the speed difference ΔV[i] and axle acceleration β[i] can be fuzzified into linguistic variables, such as positive large, positive small, zero, negative small, negative large, etc., and a fuzzy rule base can be established. For example, the fuzzy rule may include: if the speed difference ΔV is positive large and the axle acceleration β is negative large, then the initial braking force adjustment rate K[i] is negative large. The brake control unit can reason according to the fuzzy rules and output the initial braking force adjustment rate K[i] of the corresponding axle through defuzzification methods such as the center of gravity method.

[0064] (5) Regarding the coordinated control of electric braking and electromechanical braking.

[0065] In one optional implementation, the brake control unit can also interact with the traction control unit (TCU) to achieve coordinated adjustment between electric braking force and electromechanical braking force. Specifically, the brake control unit can send the coasting axle position mask, the overall braking force demand trend ΔF_total, and the suggested electric braking adjustment rate K_ed_req to the traction control unit. The traction control unit can provide feedback to the brake control unit on the actual electric braking output F_ed_actual and the electric braking system status, where the electric braking system status may include electric braking availability, braking limit status, etc.

[0066] During the force reduction phase, when any axle slips, the brake control unit can send a suggested electric brake adjustment rate K_ed_req to the traction control unit while calculating the electromechanical braking force adjustment rate K_emb[i]. K_ed_req can typically be negative. The traction control unit can reduce the electric braking force of the relevant axle based on K_ed_req, so that the electric braking force and the electromechanical braking force change in tandem at corresponding rates during the force reduction process, thereby ensuring a smooth decrease in the total braking force.

[0067] During the recovery phase, when coasting begins to recover, for example, when the axle acceleration β[i] changes from negative to positive, the brake control unit can instruct the traction control unit to restore the electric braking force to the corresponding level at a preset recovery rate K_ed_recovery, and further control the electromechanical brake calipers to restore the remaining braking force according to the electromechanical braking force adjustment rate K_emb[i]. Thus, the changes in electric and electromechanical braking forces can be coordinated during the recovery process, and the braking force distribution between each axle can be balanced.

[0068] (6) Regarding the smooth processing of control commands and clamp execution.

[0069] In this embodiment, to avoid abrupt changes in the target braking force adjustment rate, a smoothing filter can be applied to the target braking force adjustment rate to obtain a smoothed braking force adjustment rate K_cmd[i]. For example, if the target braking force adjustment rate is denoted as K_target[i], a first-order lag filter can be used: K_cmd[i](t) = α × K_target[i](t) + (1-α) × K_cmd[i](t-1), where α∈(0,1] is the filter coefficient, K_target[i](t) represents the target braking force adjustment rate of the i-th axle at the current moment, K_cmd[i](t-1) represents the smoothed braking force adjustment rate of the i-th axle at the previous moment, and K_cmd[i](t) represents the smoothed braking force adjustment rate of the i-th axle at the current moment. The filter coefficient α can be used to adjust the response speed and the degree of smoothing.

[0070] After obtaining the smoothed braking force adjustment rate K_cmd[i], the change in braking force per unit time after smoothing can be determined based on K_cmd[i]. Starting from the current actual braking force F_actual[i], and using the change in braking force per unit time after smoothing as the slope, a target braking force change curve for a future preset time period Δt is generated. For example, if the change in braking force per unit time after smoothing is denoted as ΔF_smooth[i], then the target braking force change curve can be expressed as F_target[i](τ) = F_actual[i] + ΔF_smooth[i] × τ, where τ∈[0,Δt]. In this expression, F_target[i](τ) represents the target braking force of the i-th axle at the time corresponding to the time variable τ, F_actual[i] represents the current actual braking force, and ΔF_smooth[i] represents the change in braking force per unit time after smoothing.

[0071] After generating the target braking force variation curve, the brake control unit can determine the target braking force corresponding to the current control moment based on the target braking force variation curve, and determine the corresponding target clamping force based on the target braking force. The motor drive control unit can receive the target clamping force or drive control command output by the brake control unit, and adjust the drive current of the drive motor in the electromechanical brake caliper according to the target clamping force or drive control command.

[0072] The force sensor in the electromechanical brake caliper detects the actual clamping force and feeds it back to the brake control unit. The brake control unit compares the actual clamping force with the target clamping force to obtain the clamping force deviation. Based on the clamping force deviation, it adjusts the drive current of the drive motor to make the actual clamping force track the target clamping force. Specifically, when the actual clamping force is less than the target clamping force, the drive current of the drive motor can be adjusted to increase the actual clamping force of the electromechanical brake caliper; when the actual clamping force is greater than the target clamping force, the drive current of the drive motor can be adjusted to decrease the actual clamping force of the electromechanical brake caliper; when the deviation between the actual clamping force and the target clamping force is small, the electromechanical brake caliper can maintain the corresponding clamping force output. In this way, a force closed-loop control process with clamping force as the feedback quantity is formed, so that the actual braking force of the corresponding axle is adjusted according to the target braking force change curve.

[0073] (7) Regarding the optimal slip ratio control mode.

[0074] In one alternative implementation, the braking control unit can switch to optimal slip ratio control mode under high-speed operating conditions or low-adhesion road sections. For example, this control mode can be activated when the vehicle speed V_ref is greater than 80 km / h, or when the vehicle is on a known low-adhesion road section. In optimal slip ratio control mode, the control objective is no longer to make the speed difference ΔV approach zero, but rather to stabilize the slip ratio λ[i] within a preset optimal range [λ_min, λ_max]. For example, the preset optimal range can be 3% to 12%.

[0075] In this mode, the brake control unit can determine the initial braking force adjustment rate of the corresponding axle based on the deviation between the slip ratio λ[i] and the preset optimal range, as well as the rate of change of this deviation. When the slip ratio λ[i] is lower than the preset optimal range, the braking force can be appropriately increased; when the slip ratio λ[i] is higher than the preset optimal range, the braking force can be decreased; when the slip ratio λ[i] is within the preset optimal range, the braking force can be maintained or slightly adjusted. By actively maintaining the controlled slip amount, the wheel-rail adhesion utilization can be kept within an optimal range, thereby improving the available braking force.

[0076] It should be noted that, as can be seen from the above method, this application does not change the braking force according to a fixed adjustment amount or a fixed adjustment rate after detecting skidding. Instead, it determines the initial braking force adjustment rate K[i] of the corresponding axle based on skidding state parameters such as speed difference ΔV[i] and axle acceleration β[i], so that the braking force adjustment direction and speed represented by the initial braking force adjustment rate can match the skidding degree and change trend of the corresponding axle. When there is a risk of rapid deterioration of skidding, the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper can be used to quickly reduce the braking force to suppress further axle skidding. During the skidding recovery process, the braking force can be gradually restored according to the axle acceleration and speed difference reduction rate to reduce the risk of skidding again due to excessively rapid braking force recovery. At the same time, this application can determine the target braking force adjustment rate based on the initial braking force adjustment rate, and perform smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate. Furthermore, the change in braking force per unit time after smoothing is determined based on the smoothed braking force adjustment rate, and a target braking force change curve is generated based on the change in braking force per unit time after smoothing. Therefore, the target braking force can change with time according to the corresponding direction and rate of change, reducing jumps in the target braking force command and improving the continuity and smoothness of the braking force adjustment process. Furthermore, through actual clamping force feedback, clamping force deviation calculation, and drive current adjustment, the actual clamping force of the electromechanical brake caliper can track the target clamping force, thereby improving the accuracy of the electromechanical brake caliper in executing the target braking force change curve.

[0077] As can be seen, this application provides an anti-slip control method based on electromechanical brake calipers, which involves acquiring the axle speed of each axle in a rail vehicle; determining the vehicle speed based on the axle speed, and determining the corresponding axle's slip state parameters based on the axle speed and the vehicle speed; determining the target braking force adjustment rate for the corresponding axle based on the slip state parameters; the target braking force adjustment rate characterizing the change in electromechanical braking force of the corresponding axle per unit time; performing smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate; determining the smoothed change in braking force per unit time based on the smoothed braking force adjustment rate; generating a target braking force change curve for the corresponding axle within a preset time period, using the actual braking force of the corresponding axle as the starting point and the smoothed change in braking force per unit time as the slope; and controlling the electromechanical brake calipers of the corresponding axle to adjust the braking force according to the target braking force change curve, thereby achieving anti-slip control of the corresponding axle based on the adjusted braking force. Therefore, this application obtains the axle speed of each axle in the rail vehicle and determines the vehicle speed based on the axle speed to determine the coasting state parameters of the corresponding axle. On this basis, instead of directly adjusting the electromechanical braking force according to a fixed amplitude or fixed rate, it first determines the target braking force adjustment rate of the corresponding axle based on the coasting state parameters, then performs smoothing filtering on the target braking force adjustment rate, and determines the change in braking force per unit time based on the smoothed braking force adjustment rate. Taking the actual braking force of the corresponding axle as the starting point and the change in braking force per unit time as the slope, a target braking force change curve of the corresponding axle within a preset time period is generated, thereby controlling the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve. Therefore, this application enables the change process of electromechanical braking force to match the sliding state parameters of the corresponding axle, reducing the risk of untimely or inaccurate braking force adjustment due to a fixed braking force adjustment method; at the same time, by constraining the change process of braking force within a unit time by the target braking force change curve, it can reduce the longitudinal impact of sudden braking force changes on the vehicle, improve the continuity and smoothness of the braking force adjustment process, and thus improve the anti-skid control effect of rail vehicles.

[0078] Accordingly, this application also discloses an anti-slip control device based on an electromechanical brake caliper, see [link to relevant documentation]. Figure 3 As shown, the device includes: The axle speed acquisition module 11 is used to acquire the axle speed of each axle in the rail vehicle; The state parameter determination module 12 is used to determine the vehicle speed of the rail vehicle based on the axle speed, and to determine the sliding state parameters of the corresponding axle based on the axle speed and the vehicle speed of each axle. The adjustment rate determination module 13 is used to determine the target braking force adjustment rate of the corresponding axle based on the coasting state parameters; the target braking force adjustment rate is used to characterize the change in the electromechanical braking force of the corresponding axle per unit time. The braking force change curve generation module 14 is used to perform smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate, determine the amount of braking force change per unit time based on the smoothed braking force adjustment rate, and generate the target braking force change curve of the corresponding axle within a preset time period with the actual braking force of the corresponding axle as the starting point and the amount of braking force change per unit time as the slope. The axle anti-slip control module 15 is used to control the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle according to the adjusted braking force.

[0079] For more detailed information on the working process of each of the above modules, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0080] Furthermore, embodiments of this application also provide an electronic device. Figure 4 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content of the diagram should not be construed as limiting the scope of this application.

[0081] Figure 4 This is a schematic diagram of the structure of an electronic device 20 provided in an embodiment of this application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a display screen 23, an input / output interface 24, a communication interface 25, a power supply 26, and a communication bus 27. The memory 22 stores a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the anti-slip control method based on electromechanical brake calipers disclosed in any of the foregoing embodiments. Alternatively, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0082] In this embodiment, the power supply 26 is used to provide operating voltage for each hardware device on the electronic device 20; the communication interface 25 can create a data transmission channel between the electronic device 20 and external devices, and the communication protocol it follows can be any communication protocol applicable to the technical solution of this application, and is not specifically limited here; the input / output interface 24 is used to acquire external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs, and is not specifically limited here.

[0083] Furthermore, the memory 22, as a carrier for resource storage, can be a read-only memory, random access memory, disk, or optical disk, etc. The resources stored thereon may include computer programs 221, and the storage method may be temporary storage or permanent storage. In addition to including a computer program capable of performing the anti-slip control method based on electromechanical brake calipers executed by the electronic device 20 as disclosed in any of the foregoing embodiments, the computer program 221 may further include computer programs capable of performing other specific tasks.

[0084] Furthermore, embodiments of this application also disclose a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, it implements the aforementioned anti-slip control method based on electromechanical brake calipers.

[0085] For the specific steps of this method, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0086] The various embodiments in this application are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. For the same or similar parts between the various embodiments, refer to each other. As for the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and relevant parts can be referred to in the method section.

[0087] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0088] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0089] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0090] The above provides a detailed description of the anti-slip control method, device, equipment, and medium based on electromechanical brake calipers provided in this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for anti-slip control based on an electromechanical brake caliper, characterized in that, include: Obtain the axle speed of each axle in the rail vehicle; The vehicle speed of the rail vehicle is determined based on the axle speed, and the sliding state parameters of the corresponding axle are determined based on the axle speed and the vehicle speed of each axle. The target braking force adjustment rate for the corresponding axle is determined based on the coasting state parameters. The target braking force adjustment rate is used to characterize the change in electromechanical braking force of the corresponding axle per unit time. The target braking force adjustment rate is smoothed by filtering to obtain a smoothed braking force adjustment rate. The change in braking force per unit time is determined based on the smoothed braking force adjustment rate. Taking the actual braking force of the corresponding axle as the starting point and the change in braking force per unit time as the slope, a target braking force change curve of the corresponding axle within a preset time period is generated. The electromechanical brake calipers of the corresponding axle are controlled to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle based on the adjusted braking force. The determination of the target braking force adjustment rate for the corresponding axle based on the coasting state parameters includes: Based on the coasting state parameters of each axle, the coasting state of each axle is determined; wherein, the coasting state includes normal state, coasting aggravation state, coasting maintenance state and coasting recovery state; The initial braking force adjustment rate of the corresponding axle is determined based on the coasting state parameters of the corresponding axle, and the number of axles in the coasting aggravation state or the coasting holding state is counted. If the number of axles is less than two, it is determined that multi-axle cooperative control has not been triggered, and the initial braking force adjustment rate of the corresponding axle is determined as the target braking force adjustment rate of the corresponding axle. When there are at least two axles, it is determined that multi-axle cooperative control is triggered, and the initial braking force adjustment rate of the axle in the coasting aggravation state or the coasting holding state is processed based on the multi-axle cooperative strategy in order to obtain the target braking force adjustment rate of the corresponding axle.

2. The anti-slip control method based on electromechanical brake calipers according to claim 1, characterized in that, The step of determining the coasting state parameters of the corresponding axle based on the axle speed and the vehicle speed includes: The difference between the vehicle speed and the speed of the corresponding axle is determined as the speed difference of the corresponding axle. The axle velocity of the corresponding axle is differentially processed, and the differential processing result is filtered to obtain the axle acceleration of the corresponding axle. The ratio of the speed difference of the corresponding axle to the vehicle speed is determined as the slip ratio of the corresponding axle. The speed difference, axle acceleration, and slip ratio of the corresponding axle are determined as the slip state parameters of the corresponding axle.

3. The anti-slip control method based on electromechanical brake calipers according to claim 2, characterized in that, The process of adjusting the initial braking force rate of the axle in the coasting aggravation state or the coasting hold state based on the multi-axle cooperative strategy to obtain the target braking force adjustment rate of the corresponding axle includes: A reference axle is determined from the axles that are in the coasting acceleration state or the coasting hold state; The initial braking force adjustment rate of the reference axis is corrected, and the corrected braking force adjustment rate is determined as the target braking force adjustment rate of the reference axis. The initial braking force adjustment rate of the axle other than the reference axle, which is in the state of increased coasting or the state of coasting hold, is determined as the target braking force adjustment rate of the corresponding axle.

4. The anti-slip control method based on electromechanical brake calipers according to claim 2, characterized in that, The determination of the initial braking force adjustment rate for the corresponding axle based on the coasting state parameters includes: If the corresponding axle meets the first condition, the initial braking force adjustment rate is set to the maximum negative braking force adjustment rate allowed by the electromechanical brake caliper; wherein, the first condition is that the speed difference of the corresponding axle is greater than a preset speed difference threshold, and the axle acceleration is less than a preset axle acceleration threshold. If the corresponding axle meets the second condition, the initial braking force adjustment rate is set to a negative value, and the absolute value of the initial braking force adjustment rate is positively correlated with the absolute value of the speed difference and the absolute value of the axle acceleration of the corresponding axle; wherein, the second condition includes: the speed difference of the corresponding axle is within a preset speed difference range, the axle acceleration is negative, and the first condition is not met; the preset speed difference range is set according to the vehicle operating state and anti-skid control requirements; If the corresponding axle meets the third condition, the initial braking force adjustment rate is set to a positive value, and the magnitude of the initial braking force adjustment rate is positively correlated with the axle acceleration of the corresponding axle and the rate of decrease of the speed difference; wherein, the third condition is that the axle acceleration of the corresponding axle changes from a negative value to a positive value or is within a preset positive value range, and the rate of decrease of the speed difference is the amount by which the speed difference of the corresponding axle decreases per unit time.

5. The anti-slip control method based on electromechanical brake calipers according to claim 3, characterized in that, The correction of the initial braking force adjustment rate of the reference axis includes: If the initial braking force adjustment rate of the reference axis is positive, then the initial braking force adjustment rate is multiplied by a preset correction coefficient to obtain the corrected braking force adjustment rate; wherein the preset correction coefficient is greater than or equal to 1. If the initial braking force adjustment rate of the reference axis is negative, then the initial braking force adjustment rate is triggered to change from negative to zero or positive, thus obtaining the corrected braking force adjustment rate.

6. The anti-slip control method based on electromechanical brake calipers according to claim 1, characterized in that, The step of controlling the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve includes: Obtain the actual clamping force fed back by the electromechanical brake caliper of the corresponding axle; The actual clamping force is compared with the target clamping force corresponding to the target braking force change curve to obtain the clamping force deviation. The drive current of the drive motor in the electromechanical brake caliper is adjusted according to the clamping force deviation so that the actual clamping force tracks the target clamping force.

7. An anti-slip control device based on an electromechanical brake caliper, characterized in that, include: The axle speed acquisition module is used to acquire the axle speed of each axle in the rail vehicle; The state parameter determination module is used to determine the vehicle speed of the rail vehicle based on the axle speed, and to determine the sliding state parameters of the corresponding axle based on the axle speed and the vehicle speed of each axle. The adjustment rate determination module is used to determine the target braking force adjustment rate of the corresponding axle based on the coasting state parameters. The target braking force adjustment rate is used to characterize the change in electromechanical braking force of the corresponding axle per unit time. The braking force change curve generation module is used to perform smoothing filtering on the target braking force adjustment rate to obtain a smoothed braking force adjustment rate. Based on the smoothed braking force adjustment rate, the amount of braking force change per unit time after smoothing is determined. Taking the actual braking force of the corresponding axle as the starting point and the amount of braking force change per unit time after smoothing as the slope, the target braking force change curve of the corresponding axle within a preset time period is generated. The axle anti-slip control module is used to control the electromechanical brake caliper of the corresponding axle to adjust the braking force according to the target braking force change curve, so as to achieve anti-slip control of the corresponding axle according to the adjusted braking force. The determination of the target braking force adjustment rate for the corresponding axle based on the coasting state parameters includes: Based on the coasting state parameters of each axle, the coasting state of each axle is determined; wherein, the coasting state includes normal state, coasting aggravation state, coasting maintenance state and coasting recovery state; The initial braking force adjustment rate of the corresponding axle is determined based on the coasting state parameters of the corresponding axle, and the number of axles in the coasting aggravation state or the coasting holding state is counted. If the number of axles is less than two, it is determined that multi-axle cooperative control has not been triggered, and the initial braking force adjustment rate of the corresponding axle is determined as the target braking force adjustment rate of the corresponding axle. When there are at least two axles, it is determined that multi-axle cooperative control is triggered, and the initial braking force adjustment rate of the axle in the coasting aggravation state or the coasting holding state is processed based on the multi-axle cooperative strategy in order to obtain the target braking force adjustment rate of the corresponding axle.

8. An electronic device, characterized in that, include: Memory, used to store computer programs; A processor is configured to execute the computer program to implement the anti-slip control method for electromechanical brake calipers as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, Used to store computer programs; wherein, when the computer programs are executed by a processor, they implement the anti-slip control method based on electromechanical brake calipers as described in any one of claims 1 to 6.

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