Railway vehicle braking force control method and system

Abstract

The invention discloses a rail vehicle braking force control method and system, and relates to the technical field of rail traffic vehicle braking, and the method comprises the steps: obtaining the vehicle speed in the running process of a rail vehicle, and determining the braking deceleration in combination with an obtained vehicle braking instruction; acquiring air spring pressure of the railway vehicle, and analyzing and summarizing to obtain the weight of the whole train; calculating the total braking force of the whole train according to the weight of the whole train and the braking deceleration; braking capacity comprehensive parameters of all the vehicles are obtained, and the whole-train braking capacity is obtained through analysis and summarization; according to the whole-train total braking force and the whole-train braking capacity, the braking force needing to be applied to the vehicle is obtained through calculation; based on the braking force needing to be applied to the vehicle, if the vehicle is a trailer, the braking force needing to be applied to the trailer is applied through friction braking force; if the car is a motor car, the electric braking force is applied to the motor car through priority control, and the insufficient part of the electric braking force is borne by the friction braking force. By configuring different braking capacities, the braking deceleration can be improved, and the braking distance can be shortened.

Description

Methods and systems for braking force control of rail vehicles Technical Field

[0001] This invention relates to the field of rail transit vehicle braking technology, and more specifically, to a method and system for controlling the braking force of rail vehicles. Background Technology

[0002] In the distribution of braking force in existing rail vehicles, a strategy of prioritizing electric braking and equal adhesion is generally adopted. Prioritizing electric braking maximizes the use of the motor car's electric braking across the entire train, feeding braking energy back to the power grid to achieve energy conservation and environmental protection. When braking force is insufficient, it is supplemented by the air brakes of the trailer car and the motor car. For lower braking levels, the total required braking force is less than the entire train's electric braking capacity; in this case, the motor car's electric braking can handle the required total braking force, and air braking does not need to be supplemented. The equal adhesion strategy ensures that the deceleration of all cars is consistent across the entire train, reducing the probability of skidding. The motor car prioritizes using its own electric braking, supplementing it with air braking when insufficient. The trailer car uses air braking to handle the required deceleration. For emergency braking, the total required braking force often exceeds the entire train's electric braking capacity; in this case, the motor car's electric braking has no surplus, and each car handles its own required deceleration.

[0003] Current rail vehicles typically employ an equal adhesion strategy for emergency braking, with trailer air brakes and motor vehicle electric and air brakes all capable of handling the required deceleration. However, as rail vehicle speeds continue to increase, the braking force applied by each vehicle becomes limited, primarily due to two factors: First, the adhesion limit, which is the maximum braking capacity that the wheel and rail can provide. According to test results, above 250 km / h, adhesion decreases with increasing speed. If the braking force exceeds the adhesion between the wheel and rail, skidding will occur, and if wheel lock-up occurs, it will affect vehicle safety. Therefore, train deceleration decreases with increasing speed. Second, the brake disc capacity, which is the maximum braking capacity that friction braking converts kinetic energy into heat energy for dissipation. The braking kinetic energy increases with speed. Exceeding the brake disc capacity limit will damage the brake disc and prevent it from providing the required braking force. Therefore, train deceleration cannot exceed the maximum braking capacity of the brake disc.

[0004] The friction braking system of high-speed rail transit vehicles uses brake pads pressing against brake discs to generate heat and thus braking force. Due to the spatial constraints of the vehicle bogie structure, the type and number of brake discs installed on trailers and motor cars differ. Typically, trailers are equipped with three axle discs, while motor cars are equipped with two wheel discs, resulting in different braking capacities. At low vehicle speeds, each brake disc can handle the required deceleration. However, as speed increases, the braking distance further shortens. Under this system, vehicles with lower braking capacity are more likely to reach their maximum thermal load limit, while vehicles with higher braking capacity still have some surplus, thus restricting the improvement of vehicle speed and braking capacity.

[0005] No effective solutions have yet been proposed to address the problems in the relevant technologies. Summary of the Invention

[0006] In view of the problems in the related technologies, the present invention proposes a method and system for controlling the braking force of rail vehicles to overcome the above-mentioned technical problems existing in the existing related technologies.

[0007] Therefore, the specific technical solution adopted by the present invention is as follows: According to one aspect of the present invention, a method for controlling the braking force of a rail vehicle is provided, the method comprising the following steps: S1, obtaining the braking command of the rail vehicle; S2, obtaining the vehicle speed during the operation of the rail vehicle, and determining the braking deceleration in combination with the obtained vehicle braking command; S3, obtaining the air spring pressure of the rail vehicle, and analyzing and summarizing it to obtain the total weight of the train; S4, calculating the total braking force of the entire train based on the total weight of the train and the braking deceleration; obtaining the comprehensive parameters of the braking capacity of each vehicle, and analyzing and summarizing them to obtain the braking capacity of the entire train; calculating the braking force to be applied to this vehicle based on the total braking force and the braking capacity of the entire train; S5, based on the braking force to be applied to this vehicle, if this vehicle is a trailer, the braking force to be applied to the trailer is applied through friction braking force; if this vehicle is a motor vehicle, the electric braking force is preferentially applied to the motor vehicle, and the insufficient part of the electric braking force is borne by friction braking force.

[0008] Furthermore, the process of obtaining the vehicle speed during the operation of the rail vehicle and determining the braking deceleration in conjunction with the obtained vehicle braking command includes: obtaining several sets of axle speeds during the operation of the rail vehicle and selecting the maximum axle speed as the rail vehicle speed; and obtaining the braking deceleration based on the vehicle braking command and the vehicle speed, where the larger the braking level, the greater the braking deceleration, and the greater the vehicle speed, the smaller the braking deceleration.

[0009] Furthermore, obtaining the air spring pressure of the rail vehicles and analyzing and summarizing it to obtain the total train weight includes the following steps: S31, obtaining the air spring pressure of the rail vehicles and calculating the weight of each vehicle based on the linear mapping relationship between air spring pressure and vehicle weight; S32, summing up the weights of each vehicle based on network communication to obtain the total train weight.

[0010] Furthermore, the expression for the linear mapping relationship between air spring pressure and vehicle weight is: mi = e * Pas + f; where mi represents the weight of the i-th vehicle; e and f both represent the air spring load coefficient; and Pas represents the air spring pressure.

[0011] Furthermore, based on the total weight and braking deceleration of the entire train, the total braking force of the entire train is calculated; the comprehensive braking capacity parameters of each vehicle are obtained and analyzed to obtain the overall braking capacity of the entire train; based on the total braking force and overall braking capacity of the entire train, the braking force to be applied to this vehicle is calculated, including the following steps: S41, Calculate the total braking force of the entire train based on the total weight and braking deceleration of the entire train; S42, Obtain the comprehensive braking capacity parameters of each vehicle, calculate the vehicle braking capacity based on the composite relationship between the comprehensive braking capacity parameters of each vehicle, and obtain the overall braking capacity of the entire train by summarizing; S43, Calculate the braking force to be applied to this vehicle based on the total braking force and overall braking capacity of the entire train.

[0012] Furthermore, the formula for calculating the total braking force of the entire train is: Ftot=∑mi*a(c,v); where Ftot represents the total braking force of the entire train; ∑mi represents the total weight of the train; and a(c,v) represents the braking deceleration.

[0013] Furthermore, the comprehensive braking capacity parameters for each vehicle include the brake disc capacity coefficient, adhesion limit, and electric braking state coefficient.

[0014] Furthermore, the composite relationship between the comprehensive braking capacity parameters of each vehicle is expressed as: Eabi=f(Ebdi,Eedi)*Eali; where Eabi represents the braking capacity of the i-th vehicle; Ebdi represents the brake disc capacity coefficient of the i-th vehicle; Eedi represents the electric braking state coefficient of the i-th vehicle; and Eali represents the adhesion limit of the i-th vehicle. The calculation expression for the braking force required to be applied to this vehicle is: Fi=Eabi / ∑Eabi*Ftot; where Fi represents the braking force required to be applied to the i-th vehicle; Eabi represents the braking capacity of the i-th vehicle; ∑Eabi represents the overall braking capacity; and Ftot represents the total braking force of the entire vehicle.

[0015] Furthermore, based on the fact that the vehicle needs to apply braking force, if the vehicle is a trailer, the braking force for the trailer is applied through friction braking force; if the vehicle is a motor vehicle, the electric braking force is applied first, and the insufficient electric braking force is borne by friction braking force. The braking force, electric braking force, and friction braking force required for the vehicle do not exceed the braking capacity, so as to prevent the calculated braking force from exceeding the adhesion limit and causing slippage.

[0016] According to another aspect of the present invention, a rail vehicle braking force control system is provided. The system includes: a command acquisition module, a speed acquisition and calculation module, a pressure acquisition and vehicle weight calculation module, a braking force calculation module, a friction braking force control module, and a network communication module. The command acquisition module is used to acquire braking commands from the rail vehicle. The speed acquisition and calculation module is used to acquire the vehicle speed during operation and, in conjunction with the acquired vehicle braking commands, determine the braking deceleration. The pressure acquisition and vehicle weight calculation module is used to acquire the air spring pressure of the rail vehicle and analyze and summarize it to obtain the total train weight. The braking force calculation module is used to calculate the total braking force of the entire train based on the total train weight and braking deceleration; acquire comprehensive braking capacity parameters of each vehicle and analyze and summarize them to obtain the overall braking capacity of the entire train; and calculate the braking force based on the total braking force and the overall braking force of the entire train. The braking capacity is calculated to determine the braking force required for the vehicle. The braking force control module is used to apply braking force based on the required braking force. If the vehicle is a trailer, the braking force is applied through friction braking. If the vehicle is a motor vehicle, electric braking is prioritized, with friction braking covering any shortfall. A network communication module is used for information transmission between modules. The beneficial effects of this invention are: by configuring different braking capacities, this invention maximizes the utilization of the brake disc capacity, adhesion, and electric braking of each vehicle, which helps improve braking deceleration and shorten braking distance. It not only significantly improves overall braking deceleration and effectively shortens braking distance but also helps reduce wear on specific vehicles, improves the response efficiency and coordination of the braking system, thereby comprehensively improving the safety and economy of the rail vehicle braking process. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 is a flowchart of a rail vehicle braking force control method according to an embodiment of the present invention; Figure 2 is a principle block diagram of a rail vehicle braking force control system according to an embodiment of the present invention; Figure 3 is an example diagram of rail vehicle braking deceleration in the rail vehicle braking force control method according to an embodiment of the present invention; Figure 4 is a diagram of train-level braking information transmission in the rail vehicle braking force control method according to an embodiment of the present invention; Figure 5 is a diagram of braking force application effect in the rail vehicle braking force control method according to an embodiment of the present invention.

[0019] In the diagram: 101, Command Acquisition Module; 102, Network Communication Module; 103, Braking Force Calculation Module; 104, Speed ​​Acquisition and Calculation Module; 105, Pressure Acquisition and Vehicle Weight Calculation Module; 106, Braking Force Control Module; 200, Braking Command; 300, Vehicle Network; 400, Speed ​​Sensor; 500, Air Spring; 600, Brake Disc; 700, Traction Control Unit. Detailed Implementation

[0020] To further illustrate the various embodiments, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. These drawings are mainly used to illustrate the embodiments and can be used in conjunction with the relevant descriptions in the specification to explain the operating principles of the embodiments. With reference to these drawings, those skilled in the art should be able to understand other possible implementation methods and the advantages of the present invention. The components in the drawings are not drawn to scale, and similar component symbols are generally used to represent similar components.

[0021] According to embodiments of the present invention, a method and system for controlling the braking force of rail vehicles are provided.

[0022] The present invention will now be further described with reference to the accompanying drawings and specific embodiments. As shown in Figure 1, the rail vehicle braking force control method according to an embodiment of the present invention includes the following steps: S1, obtaining the braking command of the rail vehicle; S2, obtaining the vehicle speed during the operation of the rail vehicle, and determining the braking deceleration based on the obtained vehicle braking command; S3, obtaining the air spring pressure of the rail vehicle, and analyzing and summarizing it to obtain the total train weight; S4, calculating the total braking force of the entire train based on the total train weight and braking deceleration; obtaining the comprehensive braking capacity parameters of each vehicle, and analyzing and summarizing them to obtain the total braking capacity of the entire train; calculating the braking force to be applied to this vehicle based on the total braking force and the total braking capacity of the entire train; S5, based on the braking force to be applied to this vehicle, if this vehicle is a trailer, the braking force to be applied to the trailer is all applied through friction braking force; if this vehicle is a motor vehicle, the electric braking force is preferentially applied to the motor vehicle, and the insufficient part of the electric braking force is borne by friction braking force.

[0023] In this optional embodiment, obtaining the vehicle speed during the operation of the rail vehicle and determining the braking deceleration in combination with the obtained vehicle braking command includes: obtaining several sets of axle speeds during the operation of the rail vehicle and selecting the maximum axle speed as the rail vehicle speed; obtaining the braking deceleration based on the vehicle braking command and the vehicle speed, wherein the larger the braking level, the greater the braking deceleration, and the greater the vehicle speed, the smaller the braking deceleration.

[0024] In this optional embodiment, obtaining the air spring pressure of the rail vehicle and analyzing and summarizing it to obtain the total train weight includes the following steps: S31, obtaining the air spring pressure of the rail vehicle and calculating the weight of each vehicle based on the linear mapping relationship between the air spring pressure and the vehicle weight; S32, summing up the weights of each vehicle based on network communication to obtain the total train weight.

[0025] In this optional embodiment, the expression for the linear mapping relationship between air spring pressure and vehicle weight is: mi = e * Pas + f; where mi represents the weight of the i-th vehicle; e and f both represent the air spring load coefficient; and Pas represents the air spring pressure.

[0026] In this optional embodiment, the total braking force of the entire train is calculated based on the total weight and braking deceleration; the comprehensive braking capacity parameters of each vehicle are obtained and analyzed to obtain the overall braking capacity of the entire train; the braking force to be applied to this vehicle is calculated based on the total braking force and overall braking capacity of the entire train, including the following steps: S41, calculate the total braking force of the entire train based on the total weight and braking deceleration of the entire train; S42, obtain the comprehensive braking capacity parameters of each vehicle, calculate the vehicle braking capacity based on the composite relationship between the comprehensive braking capacity parameters of each vehicle, and obtain the overall braking capacity of the entire train by summarizing; S43, calculate the braking force to be applied to this vehicle based on the total braking force and overall braking capacity of the entire train.

[0027] In this optional embodiment, the formula for calculating the total braking force of the entire train is: Ftot=∑mi*a(c,v); where Ftot represents the total braking force of the entire train; ∑mi represents the total weight of the train; and a(c,v) represents the braking deceleration.

[0028] In this optional embodiment, the comprehensive braking capability parameters of each vehicle include the brake disc capability coefficient, adhesion limit, and electric braking state coefficient.

[0029] In this optional embodiment, the composite relationship between the comprehensive braking capacity parameters of each vehicle is expressed as: Eabi=f(Ebdi,Eedi)*Eali; where Eabi represents the braking capacity of the i-th vehicle; Ebdi represents the brake disc capacity coefficient of the i-th vehicle; Eedi represents the electric braking state coefficient of the i-th vehicle; and Eali represents the adhesion limit of the i-th vehicle. The calculation expression for the braking force to be applied to this vehicle is: Fi=Eabi / ∑Eabi*Ftot; where Fi represents the braking force to be applied to the i-th vehicle; Eabi represents the braking capacity of the i-th vehicle; ∑Eabi represents the overall braking capacity; and Ftot represents the total braking force of the entire vehicle.

[0030] In this optional embodiment, based on the braking force required for the vehicle, if the vehicle is a trailer, the braking force required for the trailer is applied through friction braking force; if the vehicle is a motor vehicle, the electric braking force is applied first for the motor vehicle, and the insufficient electric braking force is borne by friction braking force. The braking force required for the vehicle, the electric braking force, and the braking force all do not exceed the braking capacity, so as to prevent the calculated braking force from exceeding the adhesion limit and causing slippage.

[0031] It should be explained that the braking force Fi to be applied to this vehicle is calculated based on the following logic.

[0032] Step 1: Calculate the total braking force Ftot = ∑mi*a(c,v) based on the vehicle weight mi and deceleration a(c,v). Specifically, this includes the following steps: 1) Obtain the vehicle braking command c, including normal braking commands at various levels and emergency braking commands.

[0033] 2) Obtain several sets of axle velocities vj during the operation of the rail vehicle, and select the maximum axle velocity as the rail vehicle velocity v.

[0034] 3) Based on the vehicle braking command c and the vehicle speed v, obtain the braking deceleration a(c,v). The larger the braking level, the larger a(c,v) is, and the larger the vehicle speed, the smaller a(c,v) is.

[0035] 4) Obtain the vehicle air spring pressure Pas. Based on the linear relationship between vehicle weight and air spring pressure mi=e*Pas+f, calculate the vehicle weight mi, where e and f are the air spring load coefficients.

[0036] 5) Each brake control unit obtains the vehicle weight mi of other vehicle brake control units through the network, and sums them up to obtain the total train weight ∑mi, which includes the moment of inertia.

[0037] 6) Based on the total weight of the train and the braking deceleration, calculate the total braking force of the entire train, Ftot=∑mi*a(c,v).

[0038] Step 2: Calculate the braking force Fi to be applied to this vehicle based on the total braking force Ftot and the braking capacity Eabi of each vehicle.

[0039] 1) Based on the total braking force of the entire train and the braking capacity of each vehicle, calculate the braking force required for this vehicle: Fi = Eabi / ∑Eabi * Ftot. This calculation method is for adhesion control modes such as emergency braking or service braking.

[0040] 2) Each braking control unit obtains the braking capacity Eabi of other vehicles through the network and summarizes them to obtain the total braking capacity ∑Eabi of the entire train.

[0041] 3) The braking capacity is comprehensively considered by taking into account the brake disc capacity coefficient Ebd, the adhesion limit Eal, and the electric braking state coefficient Eed. The brake disc capacity coefficient takes into account the different brake disc configurations of different vehicles and the different braking capacity settings, the adhesion limit takes into account the different adhesion of different vehicles and the different braking capacity settings, and the electric braking state coefficient takes into account the different braking capacity settings when electric braking is applied.

[0042] The expression for the composite relationship between the comprehensive parameters of braking capacity of each vehicle is: Eabi=f(Ebdi,Eedi)*Eali; where Eabi represents the braking capacity of the i-th vehicle; Ebdi represents the brake disc capacity coefficient of the i-th vehicle; Eedi represents the electric braking state coefficient of the i-th vehicle; and Eali represents the adhesion limit of the i-th vehicle.

[0043] Where f(Ebdi,Eedi) axle disc carriage = u, electric brake normal wheel disc carriage = uy, electric brake abnormal wheel disc carriage = w.

[0044] Based on the configuration of 3 axle disc wheels and 2 wheel disc wheels, the braking capacity of 3 axle disc wheels is greater than that of 2 axle disc wheels. According to the ground test results, the braking capacity of the axle disc wheel is taken as u=1.12 for the electric braking wheel disc wheel with abnormal braking and w=0.9 for the wheel disc wheel wheel with abnormal braking.

[0045] When the electric brake is functioning normally, it bears most of the braking energy, and the brake disc has sufficient capacity. Therefore, the wheel disc brake's value can be set to uy=1.12 when the electric brake is functioning normally, and w=0.9 when the electric brake is not functioning normally. Optionally, to reduce the variation in wheel disc brake values ​​between y and w caused by changes in the electric brake, y=w=0.9 can be set.

[0046] The adhesion limit Eali = (v≤250km / h, k, r*v+t)*mi*hi. Where k, r, and t are the adhesion limit coefficients, with values ​​of k=1.2936, r=-0.0043, and t=2.3716. hi is the adhesion ratio of the current vehicle in the train position; normally, all cars can be taken as 1. It can be considered that the adhesion of the leading-end vehicle is worse than that of the trailing-end vehicle. For example, in an 8-car train, if car 1 is the leading-end vehicle, the adhesion ratio for car 1 can be taken as 0.95, and for cars 2-8, it can be taken as 1.05.

[0047] As shown in Figure 5, according to the braking force control method of rail vehicles, the braking force applied by the axle disc car is greater than that of the wheel disc car, which can maximize the utilization of the braking disc capacity, adhesion and electric braking of each car, which is conducive to improving braking deceleration and shortening braking distance.

[0048] As shown in Table 1, assuming all vehicles have the same weight, the actual braking capacity of the disc brake is 87 kN, and the actual braking capacity of the wheel brake is 70 kN. Without considering the different braking capacities for each vehicle, the wheel brake applies a braking force of 72 kN, exceeding its maximum braking capacity. The disc brake still has a significant margin of 15 kN, which is insufficient to meet the braking speed requirement of 1.2 m / s². 2 application.

[0049] As shown in Table 2, when the braking capacity of each vehicle is configured differently, the braking margin of both the disc axle car and the wheel disc car is 6-7 kN, and it meets the requirement of 1.2 m / s. 2 application.

[0050] Table 1: Table of applied braking force values ​​without considering the different braking capabilities of each vehicle configuration

[0051] Table 2: Values ​​of Braking Force Applied Based on Different Braking Capabilities of Each Vehicle

[0052] As shown in Figure 2, according to another embodiment of the present invention, a rail vehicle braking force control system is provided. This system includes: a command acquisition module 101, a speed acquisition and calculation module 104, a pressure acquisition and vehicle weight calculation module 105, a braking force calculation module 103, a braking force control module 106, and a network communication module 102. The command acquisition module 101 is used to acquire braking commands from the rail vehicle; the speed acquisition and calculation module 104 is used to acquire the vehicle speed during operation and, in conjunction with the acquired vehicle braking commands, determine the braking deceleration; the pressure acquisition and vehicle weight calculation module 105 is used to acquire the air spring pressure of the rail vehicle and, based on the acquired vehicle braking commands, determine the braking deceleration. The system analyzes and summarizes the total weight of the train; the braking force calculation module 103 is used to calculate the total braking force of the entire train based on the total weight and braking deceleration; it obtains the comprehensive braking capacity parameters of each vehicle and analyzes and summarizes them to obtain the braking capacity of the entire train; based on the total braking force and braking capacity of the entire train, it calculates the braking force that needs to be applied to this vehicle; the braking force control module 106 is used to apply the braking force to this vehicle based on the braking force that needs to be applied. If this vehicle is a trailer, the braking force required for the trailer is applied through friction braking force; if this vehicle is a motor vehicle, the electric braking force is applied first for the motor vehicle, and the insufficient electric braking force is borne by friction braking force; the network communication module 102 is used for information transmission between vehicles.

[0053] It should be explained that the command acquisition module 101 is used to acquire vehicle braking commands c, as shown in Figure 3, including normal braking commands C1~C7 and emergency braking command C8, which are transmitted to the braking force calculation module 103 through the internal variable path L11. Here, C0 is the adhesion limit, and all decelerations do not exceed this value.

[0054] The network communication module 102 is used for information transmission between the braking control units of each vehicle and the traction control unit. The network interaction information L12 includes vehicle weight mi, braking capacity Eabi, electric braking status Eedi, and electric braking force Fedi.

[0055] The braking force calculation module 103 is used to acquire various input information, including braking command L11, network interaction information L12, speed information L14, and vehicle weight information L15. It calculates the braking force Fi, electric braking force Fedi, and friction braking force Fepi that the vehicle needs to apply. The braking force calculation module 103 limits the required braking force Fi, electric braking force Fedi, and friction braking force Fepi to not exceed the braking capacity Eabi, to prevent the calculated braking force from exceeding the adhesion limit and causing slippage. The braking force calculation module 103 sends the electric braking force Fedi to the network communication module 102 via the network interaction information L12, and transmits the friction braking force Fepi to the friction braking force control module 106 via the internal variable path L16.

[0056] The speed acquisition and calculation module 104 is used to acquire several sets of axle speeds vj during the operation of the rail vehicle, select the maximum axle speed as the rail vehicle speed v, and transmit it to the braking force calculation module 103 through the internal variable path L14.

[0057] The pressure acquisition and vehicle weight calculation module 105 is used to acquire the air spring pressure and calculate the vehicle weight mi, which is then transmitted to the braking force calculation module 103 through the internal variable path L15.

[0058] The braking force control module 106 is used to obtain the required applied frictional braking force Fepi or electric braking force Fedi through the internal variable path L16, and control the output braking pressure to drive the brake disc or traction control unit.

[0059] As shown in Figure 4, the train-level braking information transmission includes: each braking control unit 11~18 acquiring the braking command c.

[0060] Each brake control unit 11~18 obtains the vehicle speed v from the speed sensors 31~38.

[0061] Each brake control unit 11~18 outputs friction braking force Fepi to the brake disc.

[0062] Each braking control unit 11-18 sends its own vehicle weight mi and braking capacity Eabi through the network, and simultaneously receives the vehicle weight mi and braking capacity Eabi from other braking control units through the network; it sends electric braking force command Fedi to traction braking units 22-27, and receives the electric braking status Eedi from the traction braking units.

[0063] In summary, by utilizing the above-mentioned technical solutions of the present invention, the present invention, through configuring different braking capabilities, can maximize the utilization of the braking disc capacity, adhesion, and electric braking of each vehicle, which is beneficial to improving braking deceleration and shortening braking distance. It not only significantly improves the overall braking deceleration and effectively shortens the braking distance, but also helps to reduce the wear degree of specific vehicles, improve the response efficiency and coordination of the braking system, thereby comprehensively improving the safety and economy of the braking process of rail vehicles.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for controlling braking force of rail vehicles, characterized in that, The method includes the following steps: S1, obtaining the braking command of the rail vehicle; S2, obtaining the vehicle speed during the operation of the rail vehicle, and determining the braking deceleration based on the obtained vehicle braking command; S3, obtaining the air spring pressure of the rail vehicle, and analyzing and summarizing it to obtain the total train weight; S4, calculating the total braking force of the entire train based on the total train weight and braking deceleration; obtaining the comprehensive braking capacity parameters of each vehicle, and analyzing and summarizing them to obtain the total braking capacity of the entire train; calculating the braking force required for this vehicle based on the total braking force and the total braking capacity of the entire train; S5, based on the braking force required for this vehicle, if this vehicle is a trailer, the braking force required for the trailer is applied through friction braking; if this vehicle is a motor vehicle, the electric braking force is preferentially applied to the motor vehicle, and the insufficient electric braking force is borne by friction braking.

2. The method for controlling the braking force of rail vehicles according to claim 1, characterized in that, The process of obtaining the vehicle speed during the operation of the rail vehicle and determining the braking deceleration in combination with the obtained vehicle braking command includes: obtaining several sets of axle speeds during the operation of the rail vehicle and selecting the maximum axle speed as the rail vehicle speed; obtaining the braking deceleration based on the vehicle braking command and the vehicle speed, wherein the larger the braking level, the greater the braking deceleration, and the greater the vehicle speed, the smaller the braking deceleration.

3. The method for controlling the braking force of rail vehicles according to claim 1, characterized in that, The process of obtaining the air spring pressure of the rail vehicles and analyzing and summarizing it to obtain the total train weight includes the following steps: S31, obtaining the air spring pressure of the rail vehicles and calculating the weight of each vehicle based on the linear mapping relationship between the air spring pressure and the vehicle weight; S32, summing up the weights of each vehicle based on network communication to obtain the total train weight.

4. The method for controlling the braking force of rail vehicles according to claim 3, characterized in that, The expression for the linear mapping relationship between air spring pressure and vehicle weight is: mi = e * Pas + f; where mi represents the weight of the i-th vehicle; e and f both represent the air spring load coefficient; and Pas represents the air spring pressure.

5. The method for controlling the braking force of rail vehicles according to claim 1, characterized in that, The total braking force of the entire train is calculated based on the total weight and braking deceleration; the comprehensive braking capacity parameters of each vehicle are obtained and analyzed to obtain the overall braking capacity of the entire train. The calculation of the braking force required for this car based on the total braking force and braking capacity of the entire train includes the following steps: S41, calculate the total braking force of the entire train based on the total weight and braking deceleration of the entire train; S42. Obtain the comprehensive braking capacity parameters of each vehicle, calculate the vehicle braking capacity based on the composite relationship between the comprehensive braking capacity parameters of each vehicle, and obtain the overall braking capacity of the train by summarizing; S43. Calculate the braking force to be applied to this vehicle based on the total braking force and overall braking capacity of the train.

6. The method for controlling the braking force of a rail vehicle according to claim 5, characterized in that, The formula for calculating the total braking force of the entire train is: Ftot=∑mi*a(c,v); where Ftot represents the total braking force of the entire train; ∑mi represents the weight of the entire train; and a(c,v) represents the braking deceleration.

7. The method for controlling the braking force of a rail vehicle according to claim 5, characterized in that, The comprehensive braking capability parameters for each vehicle include the brake disc capability coefficient, adhesion limit, and electric braking state coefficient.

8. The method for controlling the braking force of a rail vehicle according to claim 5, characterized in that, The expression for the composite relationship between the comprehensive parameters of the braking capacity of each vehicle is: Eabi=f(Ebdi,Eedi)*Eali; where Eabi represents the braking capacity of the i-th vehicle; Ebdi represents the brake disc capacity coefficient of the i-th vehicle; and Eedi represents the electric braking state coefficient of the i-th vehicle. Eali represents the adhesion limit of the i-th vehicle; the formula for calculating the braking force required for this vehicle is: Fi = Eabi / ∑Eabi * Ftot; In the formula, Fi represents the braking force required for the i-th vehicle; Eabi represents the braking capacity of the i-th vehicle; ∑Eabi represents the braking capacity of the entire platoon; and Ftot represents the total braking force of the entire platoon.

9. The method for controlling the braking force of a rail vehicle according to claim 5, characterized in that, The braking force required for this vehicle is applied. If this vehicle is a trailer, the braking force required for the trailer is applied through friction braking. If this vehicle is a motor vehicle, the electric braking force is applied first, and the insufficient electric braking force is borne by the friction braking force. This includes ensuring that the braking force, electric braking force and friction braking force applied to this vehicle do not exceed the braking capacity, so as to prevent the calculated braking force from exceeding the adhesion limit and causing slippage.

10. A braking force control system for rail vehicles, characterized in that, The method for controlling the braking force of a rail vehicle according to any one of claims 1-9 is characterized in that the system comprises: a command acquisition module, a speed acquisition and calculation module, a pressure acquisition and vehicle weight calculation module, a braking force calculation module, a braking force control module, and a network communication module; the command acquisition module is used to acquire the braking command of the rail vehicle; the speed acquisition and calculation module is used to acquire the vehicle speed during the operation of the rail vehicle, and determine the braking deceleration by combining the acquired vehicle braking command; the pressure acquisition and vehicle weight calculation module is used to acquire the air spring pressure of the rail vehicle, and analyze and summarize it to obtain the braking deceleration of the entire train. The system comprises the following modules: a braking force calculation module, used to calculate the total braking force of the entire train based on the total weight and braking deceleration; acquiring comprehensive braking capacity parameters of each vehicle and analyzing and summarizing them to obtain the overall braking capacity of the entire train; and calculating the braking force required for this vehicle based on the total braking force and overall braking capacity of the entire train. The braking force control module, based on the required braking force for this vehicle, applies friction braking force if the vehicle is a trailer; if the vehicle is a motor vehicle, it prioritizes applying electric braking force, with friction braking force covering any insufficient electric braking force. The network communication module is used for information transmission between the modules.

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