Train control method, storage medium, and on-board controller
By using elliptic curve algorithm to determine the long and short half-axles of the train, stepless control of the train is achieved, solving the problem of low accuracy in speed graded control and improving the ultimate performance and operational efficiency of train operation speed.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- BYD CO LTD
- Filing Date
- 2022-09-29
- Publication Date
- 2026-08-04
AI Technical Summary
In existing train control technologies, speed graded control has low precision and cannot fully utilize the ultimate performance of train motors, resulting in limited operating speed.
Using an elliptic curve algorithm, the major and minor semi-axles are determined based on the difference between the train's commanded speed and current speed. The target elliptic curve represents the mapping relationship between the speed change time and acceleration, thereby achieving stepless control of the train.
It improves the control precision of train speed, enables the train motor to perform at its maximum capacity, improves operational efficiency, and avoids triggering the automatic protection system on lines with complex speed limits.
Smart Images
Figure CN117818369B_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to the field of train control technology, specifically to a train control method, a storage medium, and an on-board controller. Background Technology
[0002] With the rapid development of my country's rail transit, the demand for high-efficiency and high-density train operation is constantly increasing, and the requirements for train control technology in rail transit are also becoming more and more stringent. At present, automatic train control systems usually adjust traction or braking based on the difference between the actual speed and the commanded speed. By classifying the train's traction and braking forces into levels, and then adjusting the gears based on the difference, speed-level control is achieved.
[0003] However, the control granularity of this scheme depends on the accuracy of the level division and cannot utilize the ultimate performance of the train motor, resulting in limited operating speed. Summary of the Invention
[0004] The purpose of this disclosure is to provide a train control method, storage medium, and on-board controller to solve the problems of low accuracy in train speed graded control and inability to utilize the extreme performance of train motors.
[0005] To achieve the above objectives, a first aspect of this disclosure provides a train control method, the method comprising:
[0006] Obtain the commanded speed of the train and the current speed of the train;
[0007] According to a preset elliptic curve algorithm, based on the difference between the command speed and the current speed, the major and minor axes of the ellipse are determined to obtain the target elliptic curve in a preset coordinate system. In the preset coordinate system, the first axis perpendicular to the major axis represents acceleration, and the second axis perpendicular to the minor axis represents the change time. The area of the region enclosed by the target elliptic curve and the first and second axes is equal to the absolute value of the difference between the command speed and the current speed.
[0008] The train's speed change is controlled based on the target elliptic curve, which represents the mapping relationship between the train's speed change time and acceleration.
[0009] Optionally, determining the major and minor axes of the ellipse based on the difference between the commanded velocity and the current velocity according to a preset elliptic curve algorithm includes:
[0010] If the maximum reference acceleration of the train is less than or equal to the actual maximum acceleration of the train, the actual maximum acceleration is taken as the minor semi-axis, and the major semi-axis is determined based on the difference between the commanded speed and the current speed according to the elliptic curve algorithm.
[0011] Wherein, when the commanded speed is greater than the current speed, the maximum reference acceleration is the maximum reference traction acceleration, and the actual maximum acceleration is the actual maximum traction acceleration;
[0012] When the commanded speed is less than the current speed, the maximum reference acceleration is the absolute value of the maximum reference braking deceleration, and the actual maximum acceleration is the absolute value of the actual maximum braking deceleration.
[0013] Optionally, if the maximum reference acceleration of the train is less than the actual maximum acceleration of the train, the actual maximum acceleration is used as the minor semi-axis, and the major semi-axis is determined based on the difference between the commanded speed and the current speed according to the elliptic curve algorithm. Then, controlling the train's speed change based on the target elliptic curve representing the mapping relationship between the train's shift time and acceleration includes:
[0014] Within a first preset time period, the speed change rate value used to control the train is determined from the mapping relationship between the train's speed change time and acceleration represented by the target elliptic curve according to a preset period, so that the change rate between each two adjacent speed change rate values is less than a first preset threshold.
[0015] Specifically, when the commanded speed is greater than the current speed, the speed change rate value is output as the acceleration value to control the train; when the commanded speed is less than the current speed, the speed change rate value is output as the deceleration value to control the train.
[0016] Optionally, determining the major and minor axes of the ellipse based on the difference between the commanded speed and the current speed according to a preset elliptic curve algorithm includes:
[0017] The target reference acceleration time of the train is determined based on the preset relationship between the train's preset reference acceleration, the current speed, and the commanded speed and the train's reference acceleration time.
[0018] If the maximum reference acceleration time of the train is greater than the target reference acceleration time, the target reference acceleration time is taken as the major semi-axis, and the minor semi-axis is determined based on the difference between the command speed and the current speed according to the elliptic curve algorithm.
[0019] Optionally, if the maximum reference acceleration time of the train is greater than or equal to the target reference acceleration time, the target reference acceleration time is used as the major semi-axis, and the minor semi-axis is determined based on the difference between the command speed and the current speed according to the elliptic curve algorithm. Then, controlling the train's speed change based on the mapping relationship between the train's shift time and acceleration represented by the target elliptic curve includes:
[0020] At the initial moment of the second axis, the initial speed change rate value is obtained from the target elliptic curve representing the mapping relationship between the train's speed change time and acceleration.
[0021] Determine whether the initial rate of change is greater than the actual maximum acceleration of the train;
[0022] If the initial speed change rate is greater than the actual maximum acceleration of the train, the actual maximum acceleration is output as the speed change rate value to control the train.
[0023] Specifically, when the commanded speed is greater than the current speed, the speed change rate value is output as the acceleration value to control the train; when the commanded speed is less than the current speed, the speed change rate value is output as the deceleration value to control the train.
[0024] Optionally, the method further includes:
[0025] The rate of change of the train from its current acceleration to the speed change rate value is controlled to be less than a second preset threshold.
[0026] Optionally, the maximum reference acceleration of the train is determined in the following manner:
[0027] Based on the preset relationship between the train's preset reference acceleration, the current speed, and the commanded speed and the train's reference acceleration time, the target reference acceleration time of the train is determined as the first reference major axis. Based on the difference between the commanded speed and the current speed according to the elliptic curve algorithm, the first reference minor axis is determined, and the first reference minor axis is used as the train's maximum reference acceleration.
[0028] Optionally, the maximum reference acceleration time of the train is determined as follows:
[0029] The actual maximum acceleration of the train is used as the second reference minor axis, and the second reference major axis is determined based on the difference between the command speed and the current speed according to the elliptic curve algorithm. The second reference major axis is used as the maximum reference acceleration time of the train.
[0030] A second aspect of this disclosure also provides a non-transitory computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the steps of the method described in any of the first aspects above.
[0031] A third aspect of this disclosure also provides an on-board controller, comprising:
[0032] A memory on which computer programs are stored;
[0033] A processor for executing the computer program in the memory to implement the steps of the method described in any of the first aspects above.
[0034] The above technical solution can achieve at least the following technical effects:
[0035] First, the commanded speed and current speed of the train are obtained. Then, based on a preset elliptic curve algorithm, the major and minor axes of the ellipse representing the train are determined according to the difference between the commanded speed and the current speed, resulting in a target elliptic curve in a preset coordinate system. Finally, the train's speed change is controlled based on the mapping relationship between the train's deceleration time and acceleration represented by the target elliptic curve. This method utilizes the elliptic curve algorithm to achieve stepless speed control of the train, thereby improving the control accuracy and maximizing the performance of the train's motor, allowing the train to reach its maximum speed and improving operational efficiency.
[0036] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description
[0037] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings:
[0038] Figure 1 This is a schematic flowchart of a train control method provided in an embodiment of this disclosure;
[0039] Figure 2 This is a schematic diagram of an elliptic curve provided in an embodiment of this disclosure;
[0040] Figure 3 This is a schematic diagram of the change curve of a train's speed change rate versus time, provided in an embodiment of this disclosure;
[0041] Figure 4 This is a schematic diagram of the change curve of train speed versus time provided in an embodiment of this disclosure;
[0042] Figure 5 This is a schematic diagram illustrating the process of determining the value of the semi-major axis 'a' according to an embodiment of this disclosure;
[0043] Figure 6 This is a schematic diagram of another train speed change rate versus time curve provided in this embodiment of the present disclosure;
[0044] Figure 7 This is a schematic diagram of another train speed versus time curve provided in this embodiment of the present disclosure;
[0045] Figure 8 This is a schematic diagram illustrating the process of determining the value of the short semi-axis b according to an embodiment of this disclosure;
[0046] Figure 9 This is a schematic diagram of a train control system according to an embodiment of the present disclosure;
[0047] Figure 10 This is a schematic diagram of an on-board controller shown in an embodiment of this disclosure. Detailed Implementation
[0048] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.
[0049] It should be understood that the various steps described in the method embodiments of this disclosure may be performed in different orders and / or in parallel. Furthermore, method embodiments may include additional steps and / or omit the steps shown. The scope of this disclosure is not limited in this respect. The term "comprising" and its variations as used herein are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". Relevant definitions for other terms will be given in the description below.
[0050] It should be noted that the concepts of "first" and "second" mentioned in this disclosure are used only to distinguish different devices, modules, or units, and are not used to limit the order of functions performed by these devices, modules, or units or their interdependencies. It should also be noted that the modifications of "a" and "a plurality of" mentioned in this disclosure are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise expressly indicated in the context, they should be understood as "one or more".
[0051] Currently, automatic train control systems typically regulate traction or braking based on the difference between the train's actual speed and the commanded speed. This is achieved by classifying the train's traction and braking forces into levels and then adjusting these levels based on the difference, thus realizing graded speed control. However, the control granularity of this approach depends on the accuracy of the level classification and cannot utilize the train's motor's maximum performance, resulting in speed limitations. Furthermore, on operating lines with complex speed limit designs, the speed protection curve of the Automatic Train Protection (ATP) system is easily triggered.
[0052] In view of this, the present disclosure provides a train control method, a storage medium, and an on-board controller to solve the above problems.
[0053] The following provides a detailed description of the embodiments of the technical solution disclosed herein.
[0054] This disclosure provides a train control method, referring to... Figure 1 The method includes:
[0055] S101. Obtain the commanded speed and current speed of the train.
[0056] S102. Based on the preset elliptic curve algorithm, determine the major and minor axes of the ellipse based on the difference between the command speed and the current speed, so as to obtain the target elliptic curve in the preset coordinate system.
[0057] In the preset coordinate system, the first axis perpendicular to the major semi-axis represents acceleration, the second axis perpendicular to the minor semi-axis represents the change time, and the area of the region enclosed by the target elliptic curve and the first and second axes is equal to the absolute value of the difference between the command speed and the current speed.
[0058] For example, refer to Figure 2 In the coordinate system, the x-axis represents the change-of-speed time, the y-axis represents acceleration, 'a' represents the major semi-axis of the ellipse, 'b' represents the minor semi-axis, and 'S' represents the area enclosed by the target elliptic curve and the first and second axes—that is, the absolute value of the difference between the commanded speed and the current speed, serving as a constraint on the target elliptic curve. For the target elliptic curve, the value of 'a' represents the maximum change-of-speed time, and the value of 'b' represents the maximum acceleration. When the change-of-speed time equals the maximum change-of-speed time, the train's current speed equals the commanded speed, and at this point, the acceleration is 0; that is, the commanded acceleration is also 0.
[0059] For example, the equation for an elliptic curve is:
[0060]
[0061] The area S of the ellipse oval It can be determined by the following formula:
[0062] Soval =π*a*b (Calculation formula 2)
[0063] The absolute value of the difference between the commanded speed and the current speed, i.e. Figure 2 The area S in the middle can be determined by the following formula:
[0064]
[0065] Among them, v cmd The command speed is represented by v, the current speed is represented by v, and a*b is the area of the rectangle with side lengths a and b.
[0066] Furthermore, from the above calculation formula 3, the relationship between the major semi-axis a and the minor semi-axis b of the ellipse (based on the preset elliptic curve algorithm) is as follows:
[0067] Given the major semi-axis 'a', we can obtain the minor semi-axis 'b':
[0068]
[0069] Given the minor semi-axis b, the major semi-axis a can be obtained:
[0070]
[0071] S103. Based on the target elliptic curve representing the mapping relationship between the train's speed change time and acceleration, control the train's speed change operation.
[0072] By employing the above method, stepless control of train speed is achieved using elliptic curve algorithms, thereby improving the control accuracy of train speed and maximizing the performance of the train motor, enabling the train to reach its operating speed limit and improving operational efficiency.
[0073] To enable those skilled in the art to better understand the train control method provided in this disclosure, the above steps are illustrated in detail below.
[0074] It's worth noting that when the train's motor performs at its maximum capacity, the train operates at its maximum achievable acceleration (maximum traction acceleration during acceleration and maximum braking deceleration during deceleration), i.e., the train operates at its limits. Since the value of the long half-shaft 'a' represents the maximum speed change time, and the value of the short half-shaft 'b' represents the maximum acceleration, dynamically adjusting the value of the long half-shaft 'a' to output the train's control acceleration allows the train to change speeds within the maximum speed change time until the current speed equals the command speed (or approaches a preset range of the command speed). Similarly, dynamically adjusting the value of the short half-shaft 'b' to output the train's control acceleration allows the train to adjust from its current acceleration to its maximum acceleration, i.e., the train operates at its limits. Therefore, by utilizing the target elliptic curve and dynamically adjusting either the value of 'a' or 'b' to output the train's control acceleration, the train's speed-changing operation can be controlled. Furthermore, before controlling the train's speed-changing operation, it's necessary to determine whether to dynamically adjust the value of 'a' or 'b' to output the train's control acceleration.
[0075] In one possible approach, the train's control acceleration is determined by comparing its maximum reference acceleration with the train's actual maximum achievable acceleration. This determines whether to dynamically adjust the value of 'a' or 'b' to output the train's control acceleration. The train's maximum reference acceleration is determined as follows: based on a preset relationship between the train's preset reference acceleration, current speed, and commanded speed, and the train's reference acceleration time, the train's target reference acceleration time is determined as the first reference semi-axis. Then, using an elliptic curve algorithm, based on the difference between the commanded speed and the current speed, the first reference semi-axis is determined, and this first reference semi-axis is taken as the train's maximum reference acceleration.
[0076] For example, the preset relationship between the train's preset reference acceleration, current speed, and commanded speed, and the train's preset acceleration time can be expressed by the following formula:
[0077]
[0078] Among them, a ref This represents the train's preset reference acceleration, t. ref This represents the train's reference acceleration time. After determining the train's target reference acceleration time according to the above calculation formula 6, it is substituted into the above calculation formula 4 as the long half-axle a to obtain the short half-axle b, and the short half-axle b is taken as the train's maximum reference acceleration.
[0079] In one possible approach, based on a pre-defined elliptic curve algorithm, determining the major and minor axes of the ellipse based on the difference between the commanded speed and the current speed can be as follows: When the train's maximum reference acceleration is less than its actual maximum acceleration, the actual maximum acceleration is used as the minor axis, and the major axis is determined based on the difference between the commanded speed and the current speed using the elliptic curve algorithm. Specifically, when the commanded speed is greater than the current speed, the maximum reference acceleration is the maximum reference traction acceleration, and the actual maximum acceleration is the actual maximum traction acceleration. When the commanded speed is less than the current speed, the maximum reference acceleration is the absolute value of the maximum reference braking deceleration, and the actual maximum acceleration is the absolute value of the actual maximum braking deceleration.
[0080] For example, the train's actual maximum acceleration represents the maximum acceleration the train can achieve at the current speed. Specifically, the actual maximum traction force at the current speed can be determined experimentally, and the actual maximum traction acceleration can be obtained using Newton's second law. Similarly, the actual maximum braking deceleration corresponding to the actual maximum braking force can be obtained. When the train's maximum reference acceleration is less than its actual maximum acceleration, it means that the train can reach the command speed without extreme driving within the target reference acceleration time. Therefore, the control acceleration of the train can be output by dynamically adjusting the value of 'a'. Conversely, when the train's maximum reference acceleration is greater than or equal to its actual maximum acceleration, it means that the train needs to drive at its limit within the target reference acceleration time to reach the command speed, or even if it cannot reach the command speed by driving at its limit, it can output the control acceleration of the train by dynamically adjusting the value of 'b', i.e., driving the train at its limit to reach the command speed as quickly as possible.
[0081] Alternatively, in a possible manner, the train's control acceleration can be output by dynamically adjusting the value of 'a' or 'b' by comparing the train's target reference acceleration time with the maximum reference acceleration time the train can achieve. The train's maximum reference acceleration time is determined as follows: the train's actual maximum acceleration is used as the second reference minor axis, and based on the difference between the commanded speed and the current speed using an elliptic curve algorithm, the second reference major axis is determined, and this second reference major axis is used as the train's maximum reference acceleration time.
[0082] For example, the actual maximum acceleration of the train is substituted into the above calculation formula 5 as the short half-axis b to obtain the long half-axis a, and the long half-axis a is used as the maximum reference acceleration time of the train.
[0083] In one possible approach, the major and minor axes of the ellipse, based on the difference between the command speed and the current speed, are determined according to a preset elliptic curve algorithm. This can be achieved by: determining the train's target reference acceleration time based on a preset relationship between the train's preset reference acceleration, current speed, and command speed and the train's reference acceleration time; if the train's maximum reference acceleration time is greater than or equal to the target reference acceleration time, then using the target reference acceleration time as the major axis; and determining the minor axis based on the difference between the command speed and the current speed using the elliptic curve algorithm.
[0084] For example, when the train's maximum reference acceleration time is less than the target reference acceleration time, it means that the train can reach the command speed without pushing the limits within the target reference acceleration time. Therefore, the control acceleration of the train can be output by dynamically adjusting the value of 'a'. Conversely, when the train's maximum reference acceleration time is greater than or equal to the target reference acceleration time, it means that the train needs to push the limits within the target reference acceleration time to reach the command speed, or that pushing the limits will not be enough to reach the command speed. Therefore, the control acceleration of the train can be output by dynamically adjusting the value of 'b', i.e., pushing the train to its limits to reach the command speed as quickly as possible.
[0085] Furthermore, the steps for controlling the acceleration of the two output trains are explained in detail below.
[0086] In one possible approach, the actual maximum acceleration is used as the minor half-axis b, and the major half-axis a is determined according to the aforementioned calculation formula 5. The control acceleration of the train is output by dynamically adjusting the value of a. Specifically, when the train's maximum reference acceleration is less than its actual maximum acceleration, the actual maximum acceleration is used as the minor half-axis. Based on the difference between the command speed and the current speed using an elliptic curve algorithm, the major half-axis is determined. Then, according to the target elliptic curve representing the mapping relationship between the train's shift time and acceleration, controlling the train's shifting operation can be achieved by: within a first preset time period, determining the speed change rate value used to output the control train from the target elliptic curve representing the mapping relationship between the train's shift time and acceleration according to a preset period, such that the rate of change between any two adjacent speed change rate values is less than a first preset threshold. Specifically, when the command speed is greater than the current speed, the speed change rate value is output as the control train's acceleration value; when the command speed is less than the current speed, the speed change rate value is output as the control train's deceleration value.
[0087] For example, the target elliptic curve described above, representing the mapping relationship between the train's deceleration time and acceleration, can be expressed by the following formula:
[0088] When the current speed is less than the commanded speed, the relationship between the shift time and acceleration is:
[0089]
[0090] When the current speed is greater than the commanded speed, the relationship between the shift time and acceleration is:
[0091]
[0092] Within the first preset duration, the current preset period is used as the value of x and substituted into the above calculation formula 7 or calculation formula 8 (the specific value is determined according to the relationship between the current speed and the command speed) to output y, which is the speed change rate value. Then, the step size of one preset period is added as the new current preset period to reacquire the speed change rate value. Furthermore, the rate of change between any two adjacent speed change rate values is controlled to be less than the first preset threshold. The first preset duration and preset period are set according to requirements. The duration of the preset period is less than the duration of the first preset duration. The first preset threshold can be determined according to the impact rate requirements of the train. This disclosure does not limit this, thereby ensuring passenger comfort.
[0093] In addition, in possible embodiments, the method further includes: after a first preset duration, updating the current speed of the train, and returning to the step of taking the actual maximum acceleration as the minor axis and determining the major axis based on the difference between the command speed and the current speed according to an elliptic curve algorithm, if the maximum reference acceleration time of the train is greater than or equal to the target reference acceleration time.
[0094] For example, after the first preset time period, the train's current speed is updated, the actual maximum acceleration is redefined as the minor half-axis, and the new value of the major half-axis 'a' is determined according to the above calculation formula 5, thus obtaining a new target elliptic curve. When the train's running speed approaches the commanded speed, the train's control acceleration will gradually decrease to 0. In the above method of dynamically adjusting the value of 'a' to output the train's control acceleration, the curve of the rate of change of speed versus time is as follows: Figure 3 As shown, the train's speed versus time curve is as follows: Figure 4 As shown, the process of determining the value of the semi-major axis 'a' is as follows: Figure 5 As shown.
[0095] In one possible approach, the target reference acceleration time is used as the major semi-axis 'a', and the minor semi-axis 'b' is determined according to the aforementioned calculation formula 4. The control acceleration of the train is output by dynamically adjusting the value of 'b'. Specifically, when the train's maximum reference acceleration time is greater than or equal to the target reference acceleration time, the target reference acceleration time is used as the major semi-axis. After determining the minor semi-axis based on the difference between the command speed and the current speed using the elliptic curve algorithm, the train's speed change can be controlled by: at the initial moment of the second axle, obtaining the initial speed change rate value from the target elliptic curve's representation of the train's speed change time and acceleration; determining whether the initial speed change rate value is greater than the train's actual maximum acceleration; if the initial speed change rate value is greater than the train's actual maximum acceleration, outputting the actual maximum acceleration as the control train's speed change rate value; where the command speed is greater than the current speed, the speed change rate value is output as the control train's acceleration value; and if the command speed is less than the current speed, the speed change rate value is output as the control train's deceleration value.
[0096] In a possible manner, the method further includes: after a second preset time period, updating the current speed of the train, and returning to the step of determining the target reference acceleration time of the train based on a preset relationship between the train's preset reference acceleration, current speed, and command speed and the train's reference acceleration time.
[0097] In some possible ways, the method further includes controlling the rate of change of the train from the current acceleration to the rate of change of speed to be less than a second preset threshold.
[0098] For example, according to the above calculation formula 7 or 8, it can be determined that when the initial speed change rate value acquired by the train at the initial moment is equal to ±b, since b is greater than the actual maximum acceleration that the train can achieve, if b is used as the control acceleration of the train, it exceeds the maximum performance range of the train motor. Therefore, the actual maximum acceleration is output as the speed change rate value for controlling the train, that is, the train operates at its limit. Furthermore, in order to avoid the train's acceleration suddenly adjusting from the current acceleration to the maximum acceleration, the speed change rate of the train can be controlled to be less than a second preset threshold. The second preset threshold can be determined according to the train's impact rate requirements, and the second preset threshold can be the same as or different from the first preset threshold. This disclosure does not limit this, thereby ensuring passenger comfort.
[0099] It should be noted that the second preset duration can be determined according to requirements. It can be a fixed duration, meaning the train can periodically update its current speed, or it can be determined according to t = Δa / k, where t represents the second preset duration, Δa represents the difference between the current acceleration and the maximum acceleration, and k represents the rate of change of the train's acceleration, indicating that the train's current speed is updated when the current acceleration reaches the maximum acceleration. Based on the preset relationship between the train's preset reference acceleration, current speed, and command speed and the train's reference acceleration time, the target reference acceleration time of the train is determined. Substituting the target reference acceleration time as the value of the major semi-axis 'a' into calculation formula 4, a new value for the minor semi-axis 'b' is obtained, leading to a new target elliptic curve.
[0100] Furthermore, if the initial speed change rate acquired at the start time is equal to the actual maximum acceleration the train can achieve, it indicates that the train is operating in a limit-operation mode. As the train's speed approaches the commanded speed, the control acceleration gradually decreases to 0. In the above method of dynamically adjusting the value of b to output the train's control acceleration, the speed change rate versus time curve is as follows: Figure 6 As shown, the train's speed versus time curve is as follows: Figure 7 As shown, the process of determining the value of the minor semi-axis b is as follows: Figure 8 As shown.
[0101] It should be noted that when the train's maximum reference acceleration is greater than or equal to its actual maximum acceleration, the target reference acceleration time can be used as the major semi-axis. Based on the difference between the command speed and the current speed using an elliptic curve algorithm, the minor semi-axis is determined. Then, the target elliptic curve determined by the major and minor semi-axis represents the mapping relationship between the train's shift time and acceleration, controlling the train's speed change. That is, the control acceleration of the train is output by dynamically adjusting the value of 'b'. Alternatively, when the train's maximum reference acceleration time is less than the target reference acceleration time, the actual maximum acceleration is used as the minor semi-axis. Based on the difference between the command speed and the current speed using an elliptic curve algorithm, the major semi-axis is determined. Then, the target elliptic curve determined by the major and minor semi-axis represents the mapping relationship between the train's shift time and acceleration, controlling the train's speed change. That is, the control acceleration of the train is output by dynamically adjusting the value of 'a'. This disclosure does not limit this approach.
[0102] By employing the above method, stepless control of train speed is achieved using elliptic curve algorithms, thereby improving the control accuracy of train speed and maximizing the performance of the train motor, allowing the train to reach its operating speed limit and improving operational efficiency. Furthermore, since the train's acceleration adjustment is limited by the commanded speed, the speed protection curve of the Automatic Train Protection (ATP) system is avoided on operating lines with complex speed limit designs.
[0103] Based on the same inventive concept, this disclosure also provides a train control system, referring to... Figure 9 The system includes a selection module 901, a mode A module 902, a mode B module 903, and a control module 904.
[0104] The selection module 901 determines whether to output the train's control acceleration by dynamically adjusting the value of 'a' or 'b' based on the relationship between the train's maximum reference acceleration and its actual maximum achievable acceleration, or based on the relationship between the train's target reference acceleration time and its maximum achievable reference acceleration time. The mode A module 902 outputs the train's control acceleration by dynamically adjusting the value of 'a', and the mode B module 903 outputs the train's control acceleration by dynamically adjusting the value of 'b'. The control module 904 controls the train's operation based on the control acceleration output by the mode A module 902 or the mode B module 903.
[0105] Based on the same inventive concept, this disclosure also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described train control method steps.
[0106] Based on the same inventive concept, this disclosure also provides an in-vehicle controller, including:
[0107] A memory on which computer programs are stored;
[0108] A processor is used to execute the computer program in the memory to implement the steps of the train control method described above.
[0109] Figure 10 This is a block diagram illustrating an in-vehicle controller 1000 according to an exemplary embodiment. (Refer to...) Figure 10 The on-board controller 1000 includes a processor 1001, which may be one or more, and a memory 1002 for storing computer programs executable by the processor 1001. The computer programs stored in the memory 1002 may include one or more modules, each corresponding to a set of instructions. Furthermore, the processor 1001 may be configured to execute the computer program to perform the train control method described above.
[0110] Additionally, the vehicle controller 1000 may also include a power supply component 1005 and a communication component 1003. The power supply component 1005 can be configured to perform power management of the vehicle controller 1000, and the communication component 1003 can be configured to enable communication of the vehicle controller 1000, such as wired or wireless communication. Furthermore, the vehicle controller 1000 may also include an input / output (I / O) interface 1004. The vehicle controller 1000 can operate on an operating system, such as Windows Server, stored in the memory 1002. TM Mac OS X TM Unix TM Linux TM etc.
[0111] In another exemplary embodiment, a computer-readable storage medium including program instructions is also provided, which, when executed by a processor, implement the steps of the train control method described above. For example, the non-transitory computer-readable storage medium may be the memory 1002 including program instructions, which may be executed by the processor 1001 of the on-board controller 1000 to complete the train control method described above.
[0112] In another exemplary embodiment, a computer program product is also provided, which includes a computer program executable by a programmable device, the computer program having a code portion for performing the train control method described above when executed by the programmable device.
[0113] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.
[0114] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.
[0115] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.
Claims
1. A train control method, characterized in that, The method includes: Obtain the commanded speed of the train and the current speed of the train; According to a preset elliptic curve algorithm, based on the difference between the command speed and the current speed, the major and minor axes of the ellipse are determined to obtain the target elliptic curve in a preset coordinate system. In the preset coordinate system, the first axis perpendicular to the major axis represents acceleration, and the second axis perpendicular to the minor axis represents the change time. The area of the region enclosed by the target elliptic curve and the first and second axes is equal to the absolute value of the difference between the command speed and the current speed. The train's speed change is controlled based on the target elliptic curve characterizing the mapping relationship between the train's speed change time and acceleration. The step of determining the major and minor axes of the ellipse based on the difference between the commanded speed and the current speed according to a preset elliptic curve algorithm includes: If the maximum reference acceleration of the train is less than the actual maximum acceleration of the train, the actual maximum acceleration is taken as the minor semi-axis, and the major semi-axis is determined based on the difference between the commanded speed and the current speed according to the elliptic curve algorithm. Wherein, when the commanded speed is greater than the current speed, the maximum reference acceleration is the maximum reference traction acceleration, and the actual maximum acceleration is the actual maximum traction acceleration; When the commanded speed is less than the current speed, the maximum reference acceleration is the absolute value of the maximum reference braking deceleration, and the actual maximum acceleration is the absolute value of the actual maximum braking deceleration.
2. The method according to claim 1, characterized in that, When the maximum reference acceleration of the train is less than the actual maximum acceleration of the train, the actual maximum acceleration is used as the minor semi-axis. After determining the major semi-axis based on the difference between the commanded speed and the current speed using the elliptic curve algorithm, the step of controlling the train's speed change based on the target elliptic curve representing the mapping relationship between the train's shift time and acceleration includes: Within a first preset time period, the speed change rate value used to control the train is determined from the mapping relationship between the train's speed change time and acceleration represented by the target elliptic curve according to a preset period, so that the change rate between each two adjacent speed change rate values is less than a first preset threshold. Specifically, when the commanded speed is greater than the current speed, the speed change rate value is output as the acceleration value to control the train; when the commanded speed is less than the current speed, the speed change rate value is output as the deceleration value to control the train.
3. The method according to claim 1, characterized in that, The step of determining the major and minor semi-axis of the ellipse based on the difference between the commanded speed and the current speed according to a preset elliptic curve algorithm includes: The target reference acceleration time of the train is determined based on the preset relationship between the train's preset reference acceleration, the current speed, and the commanded speed and the train's reference acceleration time. If the maximum reference acceleration time of the train is greater than or equal to the target reference acceleration time, the target reference acceleration time is taken as the major semi-axis, and the minor semi-axis is determined based on the difference between the command speed and the current speed according to the elliptic curve algorithm.
4. The method according to claim 3, characterized in that, When the maximum reference acceleration time of the train is greater than or equal to the target reference acceleration time, the target reference acceleration time is used as the major semi-axis. After determining the minor semi-axis based on the difference between the commanded speed and the current speed using the elliptic curve algorithm, the step of controlling the train's speed change based on the mapping relationship between the train's shift time and acceleration, as represented by the target elliptic curve, includes: At the initial moment of the second axis, the initial speed change rate value is obtained from the target elliptic curve representing the mapping relationship between the train's speed change time and acceleration. Determine whether the initial rate of change is greater than the actual maximum acceleration of the train; If the initial speed change rate is greater than the actual maximum acceleration of the train, the actual maximum acceleration is output as the speed change rate value to control the train. Specifically, when the commanded speed is greater than the current speed, the speed change rate value is output as the acceleration value to control the train; when the commanded speed is less than the current speed, the speed change rate value is output as the deceleration value to control the train.
5. The method according to claim 4, characterized in that, The method further includes: The rate of change of the train from its current acceleration to the speed change rate value is controlled to be less than a second preset threshold.
6. The method according to claim 1, characterized in that, The maximum reference acceleration of the train is determined in the following manner: Based on the preset relationship between the train's preset reference acceleration, the current speed, and the commanded speed and the train's reference acceleration time, the target reference acceleration time of the train is determined as the first reference major axis. Based on the difference between the commanded speed and the current speed according to the elliptic curve algorithm, the first reference minor axis is determined, and the first reference minor axis is used as the train's maximum reference acceleration.
7. The method according to claim 2, characterized in that, The maximum reference acceleration time of the train is determined in the following manner: The actual maximum acceleration of the train is used as the second reference minor axis, and the second reference major axis is determined based on the difference between the command speed and the current speed according to the elliptic curve algorithm. The second reference major axis is used as the maximum reference acceleration time of the train.
8. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by a processor, the program implements the steps of the method described in any one of claims 1-7.
9. A vehicle-mounted controller, characterized in that, include: A memory on which computer programs are stored; A processor for executing the computer program in the memory to implement the steps of the method according to any one of claims 1-7.