A deceleration closed-loop control method and device

Abstract

The application provides a deceleration closed-loop control method and device, relates to the field of mechanical control of railway vehicles, and comprises the following steps: when the difference between the required deceleration in a braking instruction and the actual deceleration of a locomotive vehicle is greater than a preset threshold value, determining the brake cylinder pressure of the braking system of the locomotive vehicle by using a pre-constructed friction coefficient calculation model; wherein the required deceleration is issued by an automatic driving system; and the actual deceleration is obtained by actual measurement; and applying the brake cylinder pressure to the braking system to realize deceleration closed-loop control. The application can obtain the current deceleration state of a train in real time, compare the target deceleration, and thus adjust the brake cylinder pressure in real time, so as to improve the deceleration efficiency.

Description

Technical Field

[0001] This application relates to the field of mechanical control of rail vehicles, specifically a deceleration closed-loop control method and device. Background Technology

[0002] In traditional open-loop control mode, the braking control system of rail vehicles typically calculates the brake cylinder pressure based on the target deceleration corresponding to the braking command issued by the driver controller or Automatic Train Operation (ATO), i.e., calculating the total braking force requirement based on the target deceleration and vehicle weight. Then, based on the magnitude of the electric braking capacity, the braking force to be borne by the air brakes is determined, further yielding the required brake cylinder pressure. Finally, the brake actuator amplifies the brake cylinder pressure through the caliper unit and applies it to the brake disc, converting it into the final braking force. Currently, the problem is that uncertainties such as the friction coefficient between the brake disc and brake pads, wheel-rail adhesion, and conditions such as gradient turns all affect the actual deceleration of the train, ultimately impacting the actual braking effect. Therefore, using the above traditional method for braking control is usually difficult to achieve high efficiency and precision.

[0003] In open-loop control, the friction coefficient between the brake pads and the brake disc is typically considered as a constant during braking force calculation. However, the impact of temperature increases during braking on the friction coefficient between the brake disc and brake pads is not taken into account. This means that at different speeds, the deceleration produced by braking may be greater or less than expected. When the friction coefficient is greater than the preset value, the braking force is too large, which may trigger wheel anti-skid protection, increasing braking time and distance. Conversely, when the friction coefficient is less than the preset value, the braking force is too small, which may also result in a longer braking distance than expected.

[0004] To address the aforementioned technical problems, existing deceleration closed-loop control methods employ PID controllers for fuzzy control of this situation, simultaneously applying fuzzy control to two or more unknown parameters. Furthermore, the response lag of the aerodynamic structure must be considered, resulting in significant overall computational difficulties. Additionally, braking devices have strong time-sensitivity requirements, meaning the faster the response, the better, which places even greater demands on the overall computation time. In conclusion, existing deceleration closed-loop control methods have not achieved satisfactory braking control performance. Summary of the Invention

[0005] To address the problems in the prior art, this application provides a deceleration closed-loop control method and device that can obtain the current deceleration state of the train in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure in real time to improve deceleration efficiency.

[0006] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0007] In a first aspect, this application provides a deceleration closed-loop control method, comprising:

[0008] When the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, the brake cylinder pressure of the locomotive and rolling stock braking system is determined using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement.

[0009] The pressure from the brake cylinder is applied to the braking system to achieve closed-loop deceleration control.

[0010] Furthermore, the step of constructing the friction coefficient calculation model includes:

[0011] A set of instantaneous friction coefficients is constructed based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level of the locomotive and rolling stock during the historical braking process.

[0012] The instantaneous friction coefficient set is input into a neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock.

[0013] Furthermore, the steps for constructing the set of instantaneous friction coefficients include:

[0014] The first parameter is calculated based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process;

[0015] The second parameter is calculated based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process;

[0016] The instantaneous friction coefficient set is constructed based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter, and the second parameter.

[0017] Furthermore, adjusting the brake cylinder pressure of the locomotive and rolling stock braking system using a pre-built friction coefficient calculation model includes:

[0018] The current instantaneous friction coefficient is calculated using the pre-constructed friction coefficient calculation model;

[0019] Determine the corresponding demand braking force based on the demand deceleration;

[0020] The brake cylinder pressure is determined based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

[0021] Secondly, this application provides a deceleration closed-loop control device, comprising:

[0022] A brake cylinder pressure determination unit is used to determine the brake cylinder pressure of the locomotive and rolling stock braking system when the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement;

[0023] A closed-loop control unit is used to apply the pressure of the brake cylinder to the braking system to achieve closed-loop deceleration control.

[0024] Furthermore, the aforementioned deceleration closed-loop control device also includes:

[0025] The friction coefficient set construction unit is used to construct an instantaneous friction coefficient set based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level of the locomotive and rolling stock during the historical braking process.

[0026] The friction coefficient model construction unit is used to input the instantaneous friction coefficient set into the neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock.

[0027] Furthermore, the friction coefficient set construction unit includes:

[0028] The first parameter determination module is used to calculate the first parameter based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process.

[0029] The second parameter determination module is used to calculate the second parameter based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process.

[0030] The friction coefficient set construction module is used to construct the instantaneous friction coefficient set based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter, and the second parameter.

[0031] Furthermore, the brake cylinder pressure determining unit includes:

[0032] The instantaneous coefficient calculation module is used to calculate the current instantaneous friction coefficient using the pre-built friction coefficient calculation model;

[0033] The demand braking force determination module is used to determine the corresponding demand braking force based on the demand deceleration.

[0034] The brake cylinder pressure determination module is used to determine the brake cylinder pressure based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

[0035] Thirdly, this application provides an electronic device including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the steps of the deceleration closed-loop control method.

[0036] Fourthly, this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the deceleration closed-loop control method.

[0037] Fifthly, this application provides a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of the deceleration closed-loop control method.

[0038] To address the problems in existing technologies, the deceleration closed-loop control method and apparatus provided in this application can utilize deceleration sensors installed on locomotives and rolling stock to acquire the deceleration state of the locomotives and rolling stock in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure of the locomotives and rolling stock in real time. In addition, to obtain a more precise braking control effect, the method and apparatus provided in this application configure the brake cylinder pressure entirely according to the dynamic friction coefficient of the brake disc, ensuring the precise application of braking force. Its core lies in the initial preset and dynamic update process of the brake disc friction coefficient. The method and apparatus provided in this application simplify the calculation process of the braking control system and ensure the effectiveness of braking force application. It is not only applicable to air braking but also to electromechanical braking. Attached Figure Description

[0039] 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 some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a flowchart of the deceleration closed-loop control method in the embodiments of this application;

[0041] Figure 2 This is a flowchart illustrating the construction of the friction coefficient calculation model in this application embodiment;

[0042] Figure 3 This is a flowchart illustrating the construction of the instantaneous friction coefficient set in the embodiments of this application;

[0043] Figure 4This is a flowchart illustrating the adjustment of brake cylinder pressure in an embodiment of this application;

[0044] Figure 5 This is one of the structural diagrams of the deceleration closed-loop control device in the embodiments of this application;

[0045] Figure 6 This is the second structural diagram of the deceleration closed-loop control device in the embodiments of this application;

[0046] Figure 7 This is a structural diagram of the friction coefficient set construction unit in the embodiments of this application;

[0047] Figure 8 This is a structural diagram of the brake cylinder pressure determination unit in an embodiment of this application;

[0048] Figure 9 This is a schematic diagram of the structure of the electronic device in the embodiments of this application;

[0049] Figure 10 This is an overall logic block diagram of the embodiments of this application;

[0050] Figure 11 This is an overall flowchart of the embodiments of this application;

[0051] Figure 12 This is a schematic diagram of the brake disc temperature change curves at different speed levels in the embodiments of this application;

[0052] Figure 13 This is a schematic diagram showing the friction coefficient of the brake disc at different speed levels in the embodiments of this application;

[0053] Figure 14 This is a schematic diagram of the set of friction coefficients predicted based on machine learning in the embodiments of this application;

[0054] Figure 15 This is a schematic diagram of the feedback logic in the embodiments of this application. Detailed Implementation

[0055] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0056] The acquisition, storage, use, and processing of data in this application comply with relevant laws and regulations.

[0057] In one embodiment, see Figure 1In order to obtain the current deceleration state of the train in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure in real time to improve deceleration efficiency, this application provides a deceleration closed-loop control method, including:

[0058] S101: When the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, the brake cylinder pressure of the locomotive and rolling stock braking system is determined using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement.

[0059] S102: Apply the pressure of the brake cylinder to the braking system to achieve closed-loop control of deceleration.

[0060] It is understood that this application embodiment uses deceleration sensors installed on the locomotive and rolling stock to acquire the deceleration status of the locomotive and rolling stock in real time, compare it with the target deceleration, and thereby adjust the pressure of the brake cylinders in real time to ensure that the difference between the actual deceleration and the target deceleration falls within the error tolerance range. Specifically, the deceleration closed-loop control process in this application embodiment monitors the train's deceleration during braking through deceleration sensors; when the error between the actual deceleration and the target deceleration exceeds the tolerance range, the controller corrects the brake cylinder pressure until the actual deceleration meets the requirements. See the full process below. Figure 11 As shown.

[0061] Furthermore, the embodiments of this application can suppress the fluctuation of the friction coefficient caused by the rise in brake disc temperature during the braking phase of the locomotive and rolling stock, making the output of braking force more precise, especially suitable for electromechanical braking, a braking method that can respond and adjust braking force quickly. It combines machine learning technology with experimental technology to dynamically configure the friction coefficient between the brake disc and brake shoe, so that the entire friction coefficient participates in the braking process in the form of a time series, transforming the original two-parameter fuzzy control process into a single-parameter control process. See also... Figure 12 and Figure 13 Brake disc friction tests are used to determine the initial friction conditions of the brake disc. These tests yield the friction coefficient of the brake disc at different speed levels, which serves as the basic data for constructing a dataset. During continuous operation, machine learning techniques are then used to obtain the dynamic process of the friction coefficient between the brake disc and brake pads. (See [link to relevant documentation]). Figure 14 .

[0062] The above implementation process can be found in [reference]. Figure 10 As shown, the controller has a self-learning function, which uses a pre-built friction coefficient calculation model to correct the braking effect for each braking process so as to be suitable for the next braking process.

[0063] To achieve this goal quickly, this application pre-constructs a set of dynamic friction coefficients to build a friction coefficient calculation model based on this set, thereby adjusting the brake cylinder pressure. Directly using dynamic friction coefficients for braking force calculation would affect the efficiency of the brake controller, and any malfunction would impact the entire braking system. Figure 10 As can be seen, by using an additional control loop to correct the brake cylinder pressure, the accuracy of braking can be ensured without affecting the safety level of the system.

[0064] It should also be noted that the embodiments of this application use deceleration sensors for deceleration measurement, which improves the accuracy of deceleration measurement. Compared with the traditional deceleration obtained by using the speed derivative, it has advantages in both timeliness and accuracy. By setting deceleration sensors at both ends of the vehicle, readings and speed derivatives can be obtained using deceleration sensors at slopes and curves, thereby enabling the determination of operating conditions.

[0065] As described above, the deceleration closed-loop control method and apparatus provided in this application can utilize deceleration sensors installed on locomotives and rolling stock to acquire the deceleration state of the locomotives and rolling stock in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure of the locomotives and rolling stock in real time. In addition, in order to obtain a more precise braking control effect, the method and apparatus provided in this application configure the brake cylinder pressure entirely according to the dynamic friction coefficient of the disc, ensuring the precise application of braking force. Its core lies in the initial preset and dynamic update process of the brake disc friction coefficient. The method and apparatus provided in this application simplify the calculation process of the braking control system and ensure the effectiveness of the braking force application. It is not only applicable to air braking but also to electromechanical braking.

[0066] The following provides a detailed explanation of steps S101 to S103.

[0067] Figure 2 This is a specific embodiment of the deceleration closed-loop control method implemented in this application.

[0068] In one embodiment, see Figure 2 The steps for constructing the friction coefficient calculation model include:

[0069] S201: Construct a set of instantaneous friction coefficients based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level of the locomotive and rolling stock during the historical braking process;

[0070] S202: The set of instantaneous friction coefficients is input into a neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock. Specifically, it is the instantaneous friction coefficient after braking for a specific time at the current speed level.

[0071] Understandably, as the locomotives and rolling stock move, Figure 12 and Figure 13 The parameters are collected, and a dataset (a set of instantaneous friction coefficients) is constructed, which can then evolve into a honeycomb-shaped dataset. As long as the locomotive and rolling stock track remains unchanged, the system can automatically allocate the optimal friction coefficient to the brake cylinder pressure adjustment based on the speed of the locomotive and rolling stock during braking and the current state of the brake disc, thereby precisely controlling the output of braking force.

[0072] Currently, the original machine learning models used in the embodiments of this application include Long Short-Term Memory (LSTM) artificial neural networks. Since the duration of the braking process of locomotives and rolling stock is uncertain, other original models can also complete model training, but the model construction results vary. The entire system includes, but is not limited to, using any predictive algorithm and data iterative update methods for model training.

[0073] Specifically, firstly, see Figure 12 and Figure 13 The system acquires historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level during the historical braking process of locomotives and rolling stock, and constructs a set of instantaneous friction coefficients. Figure 12 and Figure 13 As can be seen, after collecting data such as brake disc temperature, instantaneous friction coefficient, braking time, and speed level, machine learning methods can be used to obtain... Figure 14 The model shown enriches the lines in the graph, thus expanding the range of data values.

[0074] By constructing a set of instantaneous friction coefficients using the aforementioned parameters, and then inputting this set into a neural network model (such as the aforementioned LSTM model) for training, a friction coefficient calculation model can be obtained. This model determines the corresponding instantaneous friction coefficient based on the locomotive's current braking time and current speed level. For details on the machine learning training process, please refer to existing technologies.

[0075] As can be seen from the above description, the deceleration closed-loop control method and device provided in this application can construct a friction coefficient calculation model.

[0076] Figure 3This is a specific embodiment of the deceleration closed-loop control method implemented in this application.

[0077] In one embodiment, see Figure 3 The steps for constructing the set of instantaneous friction coefficients include:

[0078] S301: Calculate the first parameter based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process;

[0079] S302: Calculate the second parameter based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process;

[0080] S303: Construct the instantaneous friction coefficient set based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter, and the second parameter.

[0081] It is understandable that steps S301 to S303 can be obtained from the following formula:

[0082]

[0083] Among them, F b (t) represents the final braking force, P c (t) represents the brake cylinder pressure, and θ represents the brake structure parameter, which is determined by the mechanism characteristics. It mainly uses the lever principle to amplify the brake cylinder pressure and apply it to the brake pads. μ d (t) represents the parameter set of the brake disc, and t represents the time series of the braking process. The entire formula reflects the change in braking force during the braking process.

[0084] According to the above formula, the main variables affecting braking force are the brake cylinder pressure and the friction coefficient of the brake disc. The contact characteristics between the brake disc and the brake pads can be measured through specific tests. Through these tests, the average friction coefficient can be obtained, which is used to calculate the braking force in braking control. However, the instantaneous friction coefficient is a dynamic parameter; its variation with time t during braking affects the braking effect during short-term braking. In other words, to accurately control braking force, the average friction coefficient alone is insufficient; the instantaneous friction coefficient is a necessary parameter. Typically, the friction coefficient between the brake disc and the brake pads mainly depends on the temperature of the contact surfaces and the relative velocity. Compared to the friction coefficient under steady-state conditions, a significant change in the instantaneous friction coefficient is observed since the start of the braking process. Its calculation formula is as follows:

[0085] μ d (t)=μ d0 (n v e -mvvd(t) +1)(n T e -mTTd(t) +1)

[0086] Where, μ d0 Let n be the steady-state friction coefficient. v m is the multiplication factor caused by velocity friction; v For including velocity V d One parameter of the exponential function is the coefficient; n T m is the multiplication factor caused by velocity friction; T For temperature T d One parameter coefficient of the exponential function, T d (t) is a function of temperature change with braking time t.

[0087] However, obtaining the friction coefficient for all speed levels through experiments would be prohibitively expensive in terms of both time and sample costs. Therefore, this embodiment of the application selects to measure the friction coefficient at only a few typical speed levels, and uses machine learning techniques to predict the friction coefficient for all speed levels.

[0088] Furthermore, the formula contains a total of three factors, where the second factor is the first parameter obtained in step S301, and the third factor is the second parameter obtained in step S302.

[0089] As can be seen from the above description, the deceleration closed-loop control method and device provided in this application can construct a set of instantaneous friction coefficients.

[0090] Figure 4 This is a specific embodiment of the deceleration closed-loop control method implemented in this application.

[0091] In one embodiment, see Figure 4 The method of adjusting the brake cylinder pressure of the locomotive braking system using a pre-constructed friction coefficient calculation model includes:

[0092] S401: Calculate the current instantaneous friction coefficient using the pre-built friction coefficient calculation model;

[0093] S402: Determine the corresponding demand braking force based on the demand deceleration;

[0094] S403: Determine the brake cylinder pressure based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

[0095] Understandably, when braking is required on locomotives and rolling stock, the deceleration can be controlled in a closed loop using a PI controller with "input as braking force and output as deceleration," see [reference needed]. Figure 15 At this point, the only uncertain variable for the controller is the friction coefficient between the wheel and the rail.

[0096] Figure 15In the diagram, G1(s), G2(s), and G3(s) are all system transfer functions, and P... c0 This is the initial value of the brake cylinder pressure.

[0097] Additionally, see Figure 11 The system trigger condition is when the error between the actual deceleration (a) and the theoretical deceleration (a0) exceeds ×% (e.g., Figure 11 If the braking force is maintained at 20% of the rated value for y seconds, the braking deceleration closed-loop control intervenes to correct the brake cylinder pressure. Simultaneously, the deceleration and brake cylinder pressure are recorded during the process, and the braking correction coefficient is iteratively upgraded. If wheel slip protection measures are triggered, the deceleration closed-loop control exits, and the braking force is restored to a lower level.

[0098] It should be noted that, as described in steps S401 to S403, when braking of locomotives and rolling stock is required, the friction coefficient calculation model can help calculate the current instantaneous friction coefficient of the locomotives and rolling stock. According to the aforementioned formula F... b (t)=P c (t)·θ·μ d (t) shows that since θ is a braking structure parameter determined by the mechanism characteristics and is a constant value, if we want the actual output braking force to be equal to F... b If the final braking force (equivalent to the demand braking force) is consistent with the current braking force, then P needs to be adjusted according to the constantly changing current instantaneous friction coefficient. c (t) Brake cylinder pressure, i.e., the process described in step S403. The required braking force needs to be determined based on the required deceleration. Wherein, deceleration = braking force ÷ mass.

[0099] In summary, this solution considers the thermal changes of the brake disc and brake pads, introducing a dynamic friction coefficient to adjust the brake cylinder pressure output during braking. This adjustment is performed by the brake control unit (BCU) after calculating the brake cylinder pressure, thus not affecting the operation of the original braking system. The dynamic adjustment coefficient improves braking accuracy, ensures that braking deceleration is not affected by the temperature rise of the brake disc, and avoids prolonged braking distance caused by excessive or insufficient braking force, thereby achieving precise stopping.

[0100] As can be seen from the above description, the deceleration closed-loop control method and device provided in this application can adjust the brake cylinder pressure of the locomotive and rolling stock braking system by using a pre-constructed friction coefficient calculation model.

[0101] Based on the same inventive concept, this application also provides a deceleration closed-loop control device, which can be used to implement the method described in the above embodiments, as described in the following embodiments. Since the principle of the deceleration closed-loop control device in solving the problem is similar to that of the deceleration closed-loop control method, the implementation of the deceleration closed-loop control device can refer to the implementation of the method based on software performance benchmarks, and will not be repeated. As used below, the terms "unit" or "module" can refer to a combination of software and / or hardware that implements a predetermined function. Although the system described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0102] In one embodiment, see Figure 5 In order to obtain the current deceleration status of the train in real time and compare it with the target deceleration, so as to adjust the brake cylinder pressure in real time to improve deceleration efficiency, this application provides a deceleration closed-loop control device, including: a brake cylinder pressure determination unit 501 and a closed-loop control unit 502.

[0103] The brake cylinder pressure determination unit 501 is used to determine the brake cylinder pressure of the locomotive and rolling stock braking system using a pre-built friction coefficient calculation model when the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement;

[0104] The closed-loop control unit 502 is used to apply the brake cylinder pressure to the braking system to achieve deceleration closed-loop control.

[0105] In one embodiment, see Figure 6 The deceleration closed-loop control device further includes: a friction coefficient set construction unit 601 and a friction coefficient model construction unit 602.

[0106] Friction coefficient set construction unit 601 is used to construct an instantaneous friction coefficient set based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time and historical speed level of the locomotive and rolling stock during the historical braking process.

[0107] Friction coefficient model construction unit 602 is used to input the instantaneous friction coefficient set into a neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock.

[0108] In one embodiment, see Figure 7The friction coefficient set construction unit 601 includes: a first parameter determination module 701, a second parameter determination module 702, and a friction coefficient set construction module 703.

[0109] The first parameter determination module 701 is used to calculate the first parameter based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process.

[0110] The second parameter determination module 702 is used to calculate the second parameter based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process.

[0111] Friction coefficient set construction module 703 is used to construct the instantaneous friction coefficient set based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter and the second parameter.

[0112] In one embodiment, see Figure 8 The brake cylinder pressure determination unit 501 includes: an instantaneous coefficient calculation module 801, a required braking force determination module 802, and a brake cylinder pressure determination module 803.

[0113] The instantaneous coefficient calculation module 801 is used to calculate the current instantaneous friction coefficient using the pre-constructed friction coefficient calculation model;

[0114] Demand braking force determination module 802 is used to determine the corresponding demand braking force based on the demand deceleration;

[0115] The brake cylinder pressure determination module 803 is used to determine the brake cylinder pressure based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

[0116] From a hardware perspective, in order to obtain the train's current deceleration state in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure in real time to improve deceleration efficiency, this application provides an embodiment of an electronic device for implementing all or part of the deceleration closed-loop control method. The electronic device specifically includes the following components:

[0117] The system comprises a processor, a memory, a communications interface, and a bus; wherein the processor, memory, and communications interface communicate with each other via the bus; the communications interface is used to realize information transmission between the deceleration closed-loop control device and core business systems, user terminals, and related databases and other related devices; the logic controller can be a desktop computer, tablet computer, or mobile terminal, etc., and this embodiment is not limited to these. In this embodiment, the logic controller can be implemented with reference to the embodiments of the deceleration closed-loop control method and the deceleration closed-loop control device in the embodiments, the content of which is incorporated herein, and repeated details will not be described again.

[0118] It is understood that the user terminal may include smartphones, tablet computers, network set-top boxes, portable computers, desktop computers, personal digital assistants (PDAs), in-vehicle devices, smart wearable devices, etc. Among these, the smart wearable devices may include smart glasses, smartwatches, smart bracelets, etc.

[0119] In practical applications, the deceleration closed-loop control method can be partially executed on the electronic device side as described above, or all operations can be completed in the client device. The choice can be made based on the processing power of the client device and the limitations of the user's usage scenario. This application does not impose any limitations on this. If all operations are completed in the client device, the client device may further include a processor.

[0120] The aforementioned client device may have a communication module (i.e., a communication unit) that can communicate with a remote server to achieve data transmission. The server may include a server on the task scheduling center side; in other implementation scenarios, it may also include a server on an intermediate platform, such as a server on a third-party server platform that has a communication link with the task scheduling center server. The server may include a single computer device, a server cluster consisting of multiple servers, or a distributed server structure.

[0121] Figure 9 This is a schematic block diagram illustrating the system configuration of the electronic device 9600 according to an embodiment of this application. Figure 9 As shown, the electronic device 9600 may include a central processing unit 9100 and a memory 9140; the memory 9140 is coupled to the central processing unit 9100. It is worth noting that... Figure 9 This is an example; other types of structures can also be used to supplement or replace this structure to achieve telecommunications functions or other functions.

[0122] In one embodiment, the deceleration closed-loop control method function can be integrated into the central processing unit 9100. The central processing unit 9100 can be configured to perform the following control:

[0123] S101: When the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, the brake cylinder pressure of the locomotive and rolling stock braking system is determined using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement.

[0124] S102: Apply the pressure of the brake cylinder to the braking system to achieve closed-loop control of deceleration.

[0125] As described above, the deceleration closed-loop control method and apparatus provided in this application can utilize deceleration sensors installed on locomotives and rolling stock to acquire the deceleration state of the locomotives and rolling stock in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure of the locomotives and rolling stock in real time. In addition, in order to obtain a more precise braking control effect, the method and apparatus provided in this application configure the brake cylinder pressure entirely according to the dynamic friction coefficient of the disc, ensuring the precise application of braking force. Its core lies in the initial preset and dynamic update process of the brake disc friction coefficient. The method and apparatus provided in this application simplify the calculation process of the braking control system and ensure the effectiveness of the braking force application. It is not only applicable to air braking but also to electromechanical braking.

[0126] In another embodiment, the deceleration closed-loop control device can be configured separately from the central processing unit 9100. For example, the data composite transmission device deceleration closed-loop control device can be configured as a chip connected to the central processing unit 9100, and the function of the deceleration closed-loop control method can be realized through the control of the central processing unit.

[0127] like Figure 9 As shown, the electronic device 9600 may further include: a communication module 9110, an input unit 9120, an audio processor 9130, a display 9160, and a power supply 9170. It is worth noting that the electronic device 9600 does not necessarily need to include these components. Figure 9 All components shown; in addition, the electronic device 9600 may also include Figure 9 For components not shown, please refer to existing technologies.

[0128] like Figure 9 As shown, the central processing unit 9100, sometimes also referred to as a controller or operating control, may include a microprocessor or other processor device and / or logic device, which receives inputs and controls the operation of various components of the electronic device 9600.

[0129] The memory 9140 may be, for example, one or more of a cache, flash memory, hard drive, removable media, volatile memory, non-volatile memory, or other suitable devices. It may store the aforementioned failure-related information, and also store a program for executing that information. The central processing unit 9100 may execute the program stored in the memory 9140 to perform information storage or processing, etc.

[0130] Input unit 9120 provides input to central processing unit 9100. Input unit 9120 may be, for example, a keypad or touch input device. Power supply 9170 provides power to electronic device 9600. Display 9160 displays images and text. Display may be, for example, an LCD display, but is not limited thereto.

[0131] The memory 9140 can be a solid-state memory, such as a read-only memory (ROM), random access memory (RAM), a SIM card, etc. It can also be a memory that retains information even when power is off, can be selectively erased, and contains more data; examples of this type of memory are sometimes referred to as EPROMs. The memory 9140 can also be some other type of device. The memory 9140 includes a buffer memory 9141 (sometimes referred to as a buffer). The memory 9140 may include an application / function storage unit 9142 for storing application programs and function programs or processes for executing the operation of the electronic device 9600 via the central processing unit 9100.

[0132] The memory 9140 may also include a data storage unit 9143 for storing data, such as contacts, digital data, pictures, sounds, and / or any other data used by the electronic device. The driver storage unit 9144 of the memory 9140 may include various drivers for the electronic device's communication functions and / or for performing other functions of the electronic device (such as messaging applications, address book applications, etc.).

[0133] The communication module 9110 is a transmitter / receiver 9110 that transmits and receives signals via the antenna 9111. The communication module (transmitter / receiver) 9110 is coupled to the central processing unit 9100 to provide input signals and receive output signals, which can be the same as in a conventional mobile communication terminal.

[0134] Based on different communication technologies, multiple communication modules 9110 can be configured in the same electronic device, including but not limited to cellular network modules, Bluetooth modules, and / or wireless LAN modules. The communication module (transmitter / receiver) 9110 is also coupled to a speaker 9131 and a microphone 9132 via an audio processor 9130 to provide audio output via the speaker 9131 and receive audio input from the microphone 9132, thereby realizing typical telecommunications functions. The audio processor 9130 may include any suitable buffer, decoder, amplifier, etc. Additionally, the audio processor 9130 is also coupled to a central processing unit 9100, enabling on-device recording via the microphone 9132 and on-device playback of stored audio via the speaker 9131.

[0135] Embodiments of this application also provide a computer-readable storage medium capable of implementing all steps of the deceleration closed-loop control method with a server or client execution subject in the above embodiments. The computer-readable storage medium stores a computer program that, when executed by a processor, implements all steps of the deceleration closed-loop control method with a server or client execution subject in the above embodiments. For example, when the processor executes the computer program, it implements the following steps:

[0136] S101: When the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, the brake cylinder pressure of the locomotive and rolling stock braking system is determined using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement.

[0137] S102: Apply the pressure of the brake cylinder to the braking system to achieve closed-loop control of deceleration.

[0138] As described above, the deceleration closed-loop control method and apparatus provided in this application can utilize deceleration sensors installed on locomotives and rolling stock to acquire the deceleration state of the locomotives and rolling stock in real time and compare it with the target deceleration, thereby adjusting the brake cylinder pressure of the locomotives and rolling stock in real time. In addition, in order to obtain a more precise braking control effect, the method and apparatus provided in this application configure the brake cylinder pressure entirely according to the dynamic friction coefficient of the disc, ensuring the precise application of braking force. Its core lies in the initial preset and dynamic update process of the brake disc friction coefficient. The method and apparatus provided in this application simplify the calculation process of the braking control system and ensure the effectiveness of the braking force application. It is not only applicable to air braking but also to electromechanical braking.

[0139] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, apparatus, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0140] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (devices), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0141] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0142] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0143] Specific embodiments have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. 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 invention. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A deceleration closed-loop control method, characterized in that, include: When the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold, the brake cylinder pressure of the locomotive and rolling stock braking system is determined using a pre-built friction coefficient calculation model; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement. The pressure from the brake cylinder is applied to the braking system to achieve closed-loop deceleration control. The steps for constructing the friction coefficient calculation model include: A set of instantaneous friction coefficients is constructed based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level of the locomotive and rolling stock during the historical braking process. The instantaneous friction coefficient set is input into a neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock; The steps for constructing the set of instantaneous friction coefficients include: The first parameter is calculated based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process; The second parameter is calculated based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process; The instantaneous friction coefficient set is constructed based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter, and the second parameter; in, F b (t)=P c (t)·θ·μ d (t) Among them, F b (t) represents the final braking force, P c (t) represents the brake cylinder pressure, and θ represents the brake structure parameter, determined by the mechanism characteristics. It primarily amplifies the brake cylinder pressure and applies it to the brake pads through the lever principle; μ d (t) represents the parameter set of the brake disc, and t represents the time series of the braking process; the entire formula reflects the change in braking force during the braking process. Where, μ d0 Let n be the steady-state friction coefficient. v m is the multiplication factor caused by velocity friction; v For including velocity V d One parameter of the exponential function is the coefficient; n T m is the multiplication factor caused by velocity friction; T For temperature T d One parameter coefficient of the exponential function, T d (t) is a function of temperature change with braking time t.

2. The deceleration closed-loop control method according to claim 1, characterized in that, Adjusting the brake cylinder pressure of the locomotive braking system using a pre-built friction coefficient calculation model includes: The current instantaneous friction coefficient is calculated using the pre-constructed friction coefficient calculation model; Determine the corresponding demand braking force based on the demand deceleration; The brake cylinder pressure is determined based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

3. A deceleration closed-loop control device, characterized in that, include: The brake cylinder pressure determination unit is used to determine the brake cylinder pressure of the locomotive and rolling stock braking system using a pre-built friction coefficient calculation model when the difference between the required deceleration in the braking command and the actual deceleration of the locomotive and rolling stock is greater than a preset threshold; wherein, the required deceleration is issued by the automatic driving system; and the actual deceleration is obtained by actual measurement; A closed-loop control unit is used to apply the brake cylinder pressure to the braking system to achieve closed-loop deceleration control. The friction coefficient set construction unit is used to construct an instantaneous friction coefficient set based on the historical brake disc temperature, historical instantaneous friction coefficient, historical braking time, and historical speed level of the locomotive and rolling stock during the historical braking process. A friction coefficient model construction unit is used to input the instantaneous friction coefficient set into a neural network model for training to obtain the friction coefficient calculation model; wherein, the friction coefficient calculation model is used to determine the corresponding current instantaneous friction coefficient based on the current braking time and current speed level of the locomotive and rolling stock; The friction coefficient set construction unit includes: The first parameter determination module is used to calculate the first parameter based on the first multiplication factor and the historical instantaneous speed of the locomotive and rolling stock during the historical braking process. The second parameter determination module is used to calculate the second parameter based on the second multiplication factor and the historical instantaneous temperature of the locomotive and rolling stock during the historical braking process. A friction coefficient set construction module is used to construct the instantaneous friction coefficient set based on the steady-state friction coefficient of the locomotive and rolling stock, the first parameter, and the second parameter; in, F b (t)=P c (t)·θ·μ d (t) Among them, F b (t) represents the final braking force, P c (t) represents the brake cylinder pressure, and θ represents the brake structure parameter, determined by the mechanism characteristics. It primarily amplifies the brake cylinder pressure and applies it to the brake pads through the lever principle; μ d (t) represents the parameter set of the brake disc, and t represents the time series of the braking process; the entire formula reflects the change in braking force during the braking process. Where, μ d0 Let n be the steady-state friction coefficient. v m is the multiplication factor caused by velocity friction; v For including velocity V d One parameter of the exponential function is the coefficient; n T m is the multiplication factor caused by velocity friction; T For temperature T d One parameter coefficient of the exponential function, T d (t) is a function of temperature change with braking time t.

4. The deceleration closed-loop control device according to claim 3, characterized in that, The brake cylinder pressure determination unit includes: The instantaneous coefficient calculation module is used to calculate the current instantaneous friction coefficient using the pre-built friction coefficient calculation model; The demand braking force determination module is used to determine the corresponding demand braking force based on the demand deceleration. The brake cylinder pressure determination module is used to determine the brake cylinder pressure based on the required braking force, the current instantaneous friction coefficient, and the braking structure parameters of the locomotive and rolling stock.

5. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the program, it implements the steps of the deceleration closed-loop control method according to any one of claims 1 to 2.

6. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the deceleration closed-loop control method according to any one of claims 1 to 2.

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