Selection method and device for eddy current braking level, controller and readable storage medium

Abstract

A selection method for an eddy current braking level, comprising: on the basis of a stress parameter of a train in a braking process, acquiring an ideal braking distance corresponding to each eddy current braking level, wherein the stress parameter comprises a gravity component caused by a gradient of a road in an operation line of the train; on the basis of the ideal braking distance under each eddy current braking level, and a braking starting point, acquiring a target parking position of the train; comparing the ideal braking distance with a target braking distance to acquire an ideal braking level, wherein the target distance is the distance between the braking starting point and the target parking position; acquiring the correspondence between the distance and the speed of the train in an ideal braking process; on the basis of a difference of the operation positions in the ideal braking process and an actual braking process, acquiring a control amount; and on the basis of the control amount and the ideal braking level, acquiring an actual eddy current braking level used by the train. Further disclosed are a selection device for an eddy current braking level, a controller and a readable storage medium. By means of the actual eddy current braking level obtained by the method, the parking position of the train can be closer to a designated parking position.

Description

Method and device for selecting eddy current braking level, controller, and readable storage medium

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on December 15, 2023, with application number 2023117374400 and invention name “Method and device for selecting eddy current braking level, controller, and readable storage medium”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of control, and in particular to a method and device for selecting an eddy current braking level, a controller, and a readable storage medium. Background Art

[0003] A maglev train is a rail vehicle without wheels (i.e., gear transmission mechanism). Since the train always maintains a certain gap with the track during operation, the train can reach a very high speed.

[0004] In emergency situations, maglev trains require eddy current braking. High-speed maglev trains have multiple eddy current braking levels, such as 7. Different levels correspond to different eddy current braking excitation currents, generating varying eddy current braking forces. Eddy current braking forces are the primary factor in slowing down high-speed maglev trains.

[0005] Due to the structural characteristics of high-speed maglev trains and lines, trains must stop at designated locations in the event of an emergency brake. Therefore, when the maglev train is running at high speed, the eddy current braking system of the maglev train must apply the appropriate eddy current braking level to ensure that the train can stop safely and reliably at the designated location on the line. Therefore, the selection of the eddy current braking level is particularly important.

[0006] Summary of the Invention

[0007] The present application provides a method and device for selecting an eddy current braking level, a controller, and a readable storage medium, aiming to solve the problem of how to select an eddy current braking level so that a maglev train undergoing emergency braking can stop at a specified position.

[0008] In order to achieve the above objectives, this application provides the following technical solutions:

[0009] A first aspect of the present application provides a method for selecting an eddy current braking level, comprising:

[0010] Based on the force parameters of the train during braking, the ideal braking distance corresponding to each eddy current braking level is obtained. The force parameters include: the gravity component caused by the slope of the road along the train's route;

[0011] Obtain the target stopping position of the train based on the ideal braking distance at each eddy current braking level and the braking starting point;

[0012] The ideal braking level is obtained by comparing the ideal braking distance with the target braking distance, where the target distance is the distance between the braking starting point and the target parking position;

[0013] Obtaining a correspondence between a distance and a speed of the train during an ideal braking process, wherein the ideal braking process is a process of braking using the ideal braking level;

[0014] obtaining a control amount based on a difference between an operating position during the ideal braking process and an actual braking process;

[0015] Based on the control amount and the ideal braking level, the actual eddy current braking level used by the train is obtained.

[0016] Optionally, based on the ideal braking distance at each eddy current braking level and the braking starting point, the target stopping position of the train is obtained, including:

[0017] If the distance between the braking starting point and the first preset stopping position ahead of the train is less than a distance threshold, the second preset stopping position ahead of the train is used as the target stopping position. The distance threshold is the ideal braking distance corresponding to the eddy current braking level with the maximum braking force.

[0018] If the distance between the braking starting point and the first preset parking position is greater than the distance threshold, the first preset parking position is used as the target parking position.

[0019] Optionally, the ideal braking level is obtained by comparing the ideal braking distance with the target braking distance, including:

[0020] In the process of traversing the eddy current braking levels in a preset order, the first traversed eddy current braking level k that meets the conditions and the previous eddy current braking level k-1 that meets the conditions are taken as ideal braking levels. The preset order is the order of the corresponding eddy current braking forces from low to high, and the conditions include that the corresponding ideal braking distance is less than the target braking distance.

[0021] Optionally, obtaining the correspondence between the distance and the speed of the train during the ideal braking process includes:

[0022] Obtaining a switching timing from the ideal braking level k to the ideal braking level k-1;

[0023] Based on the switching timing, the initial speed at the start of braking, the time elapsed during the ideal braking process, and the ideal braking force at the ideal braking level, a corresponding relationship between the distance and the speed during the ideal braking process is obtained.

[0024] Optionally, obtaining a switching timing from an ideal braking level k to an ideal braking level k-1 includes:

[0025] Obtaining the distance between each position during braking at the ideal braking level k and the target parking position;

[0026] Find the distance in the distance that is equal to the reference braking distance to obtain the target distance. The reference braking distance is the braking distance obtained when the train takes the speed at the target distance as the initial speed under the ideal braking level k-1.

[0027] The moment corresponding to the target distance is used as the switching opportunity.

[0028] Optionally, based on the control amount and the ideal braking level, the actual eddy current braking level used by the train is obtained, including:

[0029] Before the switching opportunity, the actual eddy current braking level is the sum of the ideal braking level k and the control amount (i.e., the control output amount). After the switching opportunity, the actual eddy current braking level is the sum of the ideal braking level k-1 and the control amount (i.e., the control output amount).

[0030] Optionally, the gravity component caused by the slope of the road in the train's running route is obtained based on the mass of the train and the slope, where the slope is the angle between the slope in the running route and the horizontal plane.

[0031] A second aspect of the present application provides a device for selecting an eddy current braking level, comprising:

[0032] A first acquisition module is configured to acquire an ideal braking distance corresponding to each eddy current braking level based on force parameters of the train during braking, wherein the force parameters include a gravity component caused by a slope of a road along the train's route;

[0033] The second acquisition module is used to obtain the target parking position of the train based on the ideal braking distance under each eddy current braking level and the braking starting point;

[0034] a third acquisition module, configured to obtain an ideal braking level by comparing an ideal braking distance with a target braking distance, where the target distance is the distance between the braking start point and the target parking position;

[0035] a fourth acquisition module, configured to acquire a correspondence between a distance and a speed of the train during an ideal braking process, wherein the ideal braking process is a process of braking using the ideal braking level;

[0036] The control module is used to obtain a control amount based on the difference between the running positions during the ideal braking process and the actual braking process, and to obtain an actual eddy current braking level used by the train based on the control amount and the ideal braking level.

[0037] A third aspect of the present application provides a controller, comprising:

[0038] memory for storing computer programs;

[0039] The processor is configured to implement the method for selecting the eddy current braking level provided in the first aspect of the present application by running a computer program.

[0040] The fourth aspect of the present application provides a readable storage medium. When the instructions in the readable storage medium are executed by a processor of an electronic device, the electronic device can execute the method for selecting the eddy current braking level provided in the first aspect of the present application.

[0041] The present application provides a method and apparatus for selecting an eddy current braking level. Based on the force parameters of a train during braking, the ideal braking distance corresponding to each eddy current braking level is obtained. The target stopping position of the train is obtained based on the ideal braking distance at each eddy current braking level and the braking starting point. The ideal braking level is obtained by comparing the ideal braking distance with the target braking distance, where the target distance is the distance between the braking starting point and the target stopping position. The corresponding relationship between the distance and speed of the train during the ideal braking process is obtained. A control variable is obtained based on the difference between the operating positions during the ideal braking process and the actual braking process. Finally, the actual eddy current braking level used by the train is obtained based on the control variable and the ideal braking level. Because the force parameters include the gravity component caused by the slope of the road along the train's operating route, the ideal braking distances corresponding to each eddy current braking level are closer to the actual distances, and the obtained ideal braking level is more accurate. Furthermore, because the difference between the ideal braking distance at the ideal braking level and the actual braking distance is used as the basis for obtaining the control variable, a more accurate control variable can be obtained, and the obtained actual eddy current braking level can thus bring the train's stopping position closer to the designated stopping position. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0043] FIG1 is a flow chart of a method for obtaining an eddy current braking level disclosed in an embodiment of the present application;

[0044] Figure 2 is an example diagram of fuzzy control to obtain the control quantity;

[0045] FIG3 is a flow chart of another method for obtaining an eddy current braking level disclosed in an embodiment of the present application;

[0046] FIG4 is a schematic structural diagram of a device for obtaining an eddy current braking level disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0047] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to be limiting of the present application. As used in the specification and appended claims of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear contrary indication in the context. It should also be understood that in the embodiments of the present application, "one or more" refers to one, two or more; "and / or" describes the association relationship of associated objects, indicating that three relationships may exist; for example, A and / or B can represent: the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship.

[0048] References to "one embodiment" or "some embodiments" in this specification mean that a particular feature, structure, or characteristic described in conjunction with that embodiment is included in one or more embodiments of the present application. Thus, phrases such as "in one embodiment," "in some embodiments," "in other embodiments," and "in yet other embodiments" appearing in various places in this specification do not necessarily refer to the same embodiment, but rather mean "one or more but not all embodiments," unless otherwise specifically emphasized. The terms "including," "comprising," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0049] The "multiple" involved in the embodiments of the present application means greater than or equal to two. It should be noted that in the description of the embodiments of the present application, the words "first" and "second" are only used for the purpose of distinguishing the description and cannot be understood as indicating or implying relative importance or order.

[0050] The eddy current braking process is controlled in stages, with multiple eddy current braking levels configured. Different levels correspond to different eddy current braking excitation currents, thereby generating varying degrees of eddy current braking force. In one example, the eddy current braking level includes seven levels, with level 7 being the maximum. The higher the level, the greater the eddy current braking force generated.

[0051] During the research, the inventors found that, in the case of emergency braking of maglev trains, there is usually a problem that the actual parking position is far away from the designated parking position. In addition, the inventors found that the cause of this problem is that the prerequisite for calculating the ideal braking distance is a straight line, and the slope gravity component caused by the slope in the line is placed in random disturbance. Taking the ideal braking curve on the straight road as the control target, the fuzzy control algorithm is used to compensate for the influence of the line slope gravity component on the final parking position. Since the eddy current braking process is graded and the maximum level is 7, if there is a long slope, a steep slope or a distance close to the set parking position during the braking process, the actual parking position of the train may be far away from the designated parking position, resulting in poor stability of the eddy current braking system.

[0052] In order to select a more appropriate eddy current braking level so that a maglev train can stop accurately at a designated location, an embodiment of the present application discloses a method for selecting an eddy current braking level, which is applied to a control system of a maglev train.

[0053] FIG1 is a flow chart of a method for obtaining an eddy current braking level according to an embodiment of the present application, comprising the following steps:

[0054] S101. Obtain an ideal braking force applied to the train during braking at each eddy current braking level.

[0055] The braking forces applied to the train during braking include: air resistance, skid friction, wear plate friction, guide electromagnet resistance, and the gravity component of the track slope.

[0056] The ideal braking force can be understood as the braking force exerted on the maglev train without considering the random interference force exerted on the maglev train during the braking process.

[0057] The ideal braking force of the train is calculated according to formula (1):

[0058] F i =F A +F E +F W +F F +F C +F S (1), where F i is the ideal braking force of the train with eddy current braking level i, i=1, 2, ... N, N is an integer greater than 2, an example of which is 7.

[0059] F A is the air resistance, F E is the eddy current braking force, F W is the sled friction force, F F is the friction force of the wear plate, F CF is the resistance of the guide electromagnet, S It is the gravity component of the road slope of the current running line, that is, the gravity component caused by the slope of the road in the current running line.

[0060] Based on (1), we can know that in this step, when calculating the ideal braking force of the train, the gravity component of the road slope F is taken into account. S As one of the bases, that is to say, the influence of the gravity component of the line slope on the train braking is taken into account.

[0061] Compared with the traditional method of taking the slope gravity component as the influencing factor of random disturbance, in this step, the slope gravity component is taken as the influencing factor of the ideal braking force (curve). Under the same conditions, the ideal braking curve obtained based on the ideal braking force obtained in this step has a smaller deviation from the actual braking curve. Therefore, the train stop position is closer to the target parking position than the traditional scheme.

[0062] The parameters required in formula (1) are obtained as follows:

[0063] Calculate the air resistance according to formula (2): F A =W1×V 2 ×10 -3 (2), where V is the running speed of the train and W1 is the air resistance coefficient when the train is running.

[0064] Taking the eddy current braking levels from level 1 to level 7 as an example, the eddy current braking levels are sequentially substituted into the eddy current braking force calculation formula (3) to obtain the eddy current braking force under each braking level of the train.

[0065] The calculation formula of eddy current braking force is: Where i is one of the eddy current braking levels, k1 is the first constant coefficient, k2 is the second constant coefficient, and k3 is the third constant coefficient. The constant coefficients can be determined based on the train's marshaling number (the train's marshaling number refers to the number of carriages in a train) and the design parameters of the eddy current braking electromagnet. V is the train's operating speed.

[0066] Use formula (4) to calculate the sled friction force: F W =μ1×Mg (4), where μ1 is the friction coefficient between the sled and the track, M is the mass of the train, and g is the acceleration due to gravity.

[0067] Use formula (5) to calculate the friction force of the wear plate:

[0068] Among them, μ2 is the friction coefficient between the wear plate and the guide rail, n is the number of train sets, and V is the speed of the train.

[0069] Calculate the guide electromagnet resistance according to formula (6): Among them, V is the running speed of the train and n is the number of train sets.

[0070] Calculate the gravity component of the road slope of the current operating line according to formula (7): F S =Mgsinα (7), where M is the mass of the train, g is the acceleration due to gravity, and α is the angle between the slope of the current running line and the horizontal plane.

[0071] Based on the above formulas, it can be understood that at different eddy current braking levels, the eddy current braking force F is respectively E , therefore, under different eddy current braking levels, there are ideal braking forces. Substituting each eddy current braking level into formula (3) to obtain the eddy current braking force F E , and further obtain the ideal braking force at each eddy current braking level.

[0072] S102. Based on the ideal braking force of the train at each eddy current braking level, obtain the ideal braking distance of the train at each eddy current braking level.

[0073] The ideal braking distance at each eddy current braking level is calculated according to formula (8):

[0074] Where M is the mass of the train, V0 is the initial braking velocity of the train, and t is the braking time of the train, which is the time from the speed at the beginning of braking to the speed being 0. i is the ideal braking force of the train at eddy current braking level i. Substitute the ideal braking force of each eddy current braking level i into formula (8) to obtain the ideal braking distance of the train at each eddy current braking level.

[0075] For ease of explanation, in this embodiment, the eddy current braking levels are taken as levels 1 to 7, and the ideal braking distances at the respective eddy current braking levels are represented by S1, S2...S7.

[0076] S103: Determine the target stopping position of the train based on the ideal braking distance at each eddy current braking level and the braking starting point.

[0077] High-speed maglev lines have several pre-set stopping locations (designated stopping locations), where trains must stop in certain situations (such as emergency braking). It's understood that if the distance from the braking point (i.e., the braking starting point) to the first stopping location ahead is less than S7, the train cannot stop at the first stopping location.

[0078] Therefore, in this step, if the distance between the braking start point and the first parking position ahead is determined to be less than S7, then, in light of the emergency stop scenario, the second parking position ahead is selected as the target parking position. It should be understood that selecting the second parking position ahead as the target parking position is a method employed to ensure a quick stop in an emergency braking scenario and is not limited to the second parking position ahead as the target parking position. If the distance between the braking start point and the first parking position ahead is determined to be greater than S7, then the first parking position ahead is selected as the target parking position. Similarly, the first parking position is not limited to being the target parking position.

[0079] It can be understood that the parking positions in front of the train are the first parking position, the second parking position, etc. according to the distance from the train from near to far.

[0080] S104: Obtain an ideal braking level and switching timing.

[0081] The distance between the braking starting point and the target parking position is called the target braking distance, denoted as S0.

[0082] Traverse in order from low to high eddy current braking levels, such as from eddy current braking level 1 to level 7, and traverse in sequence. When the ideal braking distance S under braking level k is k When it is less than S0, the eddy current braking levels k and k-1 are the ideal braking levels.

[0083] The switching time from the ideal braking level k to k-1 is: the distance from the current position of the train (i.e. the position at each moment during the braking process at the ideal braking level k) to the target parking position is equal to S' k-1 (abbreviated as reference braking distance) is equal to the moment. The current speed of the train (the speed at the current position) is the initial braking speed of the train, and the ideal braking force under the ideal braking level k-1 is F i , S' is calculated based on formula (8) k-1 .

[0084] S105: Obtain the corresponding relationship between the distance and speed of the train during the ideal braking process.

[0085] The ideal braking process is a process in which the train is braked using ideal braking levels k and k-1 under ideal braking force (i.e., without considering random interference forces) until the train stops.

[0086] The distance traveled by the train during ideal braking is calculated using formula (9): Where S is the distance traveled by the train and t is the time taken for the ideal braking process.

[0087] V in formula (9) is obtained based on formula (10):

[0088] Among them, t1 is the switching time, t is the time of ideal braking process, F k is the ideal braking force under ideal braking level k, F k-1 is the ideal braking force under the ideal braking level k-1, and V0 is the initial speed at the beginning of braking.

[0089] It will be appreciated that the ideal braking distance and speed calculated in this step constitute the ideal braking curve (speed-distance curve). This ideal braking curve represents the relationship between train speed and distance traveled (position) during the ideal braking process. As previously mentioned, considering the slope's gravity component as an influencing factor for the ideal braking force (curve), under identical conditions, the ideal braking curve derived from the ideal braking force obtained in this step will exhibit a smaller deviation from the actual braking curve.

[0090] S106: Obtain the actual braking force of the train.

[0091] Use formula (11) to calculate the actual braking force of the train: F'=F+F R (11), where F' is the actual braking force of the train, F R is the random interference force, F R =μ3F E (12), μ3 is a set of random numbers generated within a certain range, and the optional setting range is [-0.4, 0.4], F E is the eddy current braking force. The specific calculation method can be found in formula (3).

[0092] S107: Obtain the distance traveled by the train during the actual braking process.

[0093] The actual distance traveled by the train during braking is calculated using formula (13):

[0094] Where t is the actual braking time, and S' is the distance traveled by the train during the actual braking process.

[0095] S108. Calculate the error of the train's running position during braking and the change in the error.

[0096] The train position error is calculated using formula (14): e = SS' (14).

[0097] The change in error is calculated using formula (15):

[0098] S109. Use a fuzzy control method to control the error and its change to obtain a control output u.

[0099] Figure 2 shows the fuzzy control block diagram. As shown in Figure 2, the fuzzified quantization factors corresponding to e and ec are set as ke and kec, respectively. These values ​​can be set freely based on actual conditions. ke can be set to 1 / 2, and kec can be set to 1 / 4. E and EC are fuzzy sets of linguistic variables that reflect position deviation and deviation change rate, respectively. The fuzzy linguistic variables for the input variables, e and ec, are set to NB (negative large), NS (negative small), zero (ZO), PS (positive small), and PB (positive large), with a domain of {-6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6}. This means that all fuzzy linguistic variables for the input variables fall within this range. U represents the fuzzy linguistic variables for the control rule outputs, also NB, NS, ZO, PS, and PB, with a domain of {-6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6}. This means that all fuzzy linguistic variables for the control output variables fall within this range. u is the eddy current braking level after U is inversely fuzzified and rounded to an accurate value. The fuzzy control rules are mature technologies in this field and will not be described in detail.

[0100] S110 : The sum of the ideal braking level and u is used as the actual eddy current braking level of the train.

[0101] Before the above switching opportunity, the actual eddy current braking level is the sum of the ideal braking levels k and u, and after the above switching opportunity, the actual eddy current braking level is the sum of the ideal braking level k-1 and u.

[0102] It is understandable that the upper limit of the actual eddy current braking level is 7 and the lower limit is 0.

[0103] The process shown in Figure 1 uses the slope gravity component caused by the slope on the route of the maglev train as one of the bases for obtaining the ideal braking force, which in turn affects the ideal braking distance of the maglev train, so that the ideal braking distance is restricted by the slope gravity component, and the deviation from the actual braking distance is smaller, so a more accurate actual eddy current braking level can be obtained. In addition, based on the ideal braking level and the switching timing, the ideal braking distance is obtained, which can further reduce the deviation between the ideal braking distance and the actual braking distance. In summary, the actual eddy current braking level obtained by fuzzy control based on the running position error can increase the possibility of the train stopping at the designated position, especially when there is a long slope or steep slope on the line during the braking process, the train can reliably and safely stop at the designated parking position, making the train's eddy current braking system more reliable.

[0104] Compared with the traditional method of selecting the eddy current braking level, the process shown in Figure 1 can be summarized as the process shown in Figure 3, including the following steps:

[0105] S201. Based on the force parameters of the train during braking, obtain the ideal braking distance corresponding to each eddy current braking level.

[0106] Force parameters include the gravity component caused by the slope of the train's route. As previously mentioned, the gravity component of the slope is used as an influencing factor for the ideal braking force. The ideal braking distance derived from the ideal braking force is then aligned with the actual braking distance, resulting in an eddy current braking level that allows the train to stop more accurately at the designated location.

[0107] In some implementations, the force parameter also includes at least one item in formula (1) other than the gravity component due to the road slope, which is not further described here. Furthermore, the calculation methods for each force and the seven eddy current braking levels provided in the embodiment shown in FIG1 are merely examples and are not intended to be limiting.

[0108] S202: Based on the ideal braking distances at each eddy current braking level and the braking starting point, a target stopping position of the train is obtained.

[0109] An implementation of S202 may refer to S102-S103.

[0110] It is understood that the formula (8) for calculating the ideal braking distance at each eddy current braking level in S102 is merely an example and not a limitation. Other formulas for calculating distances may also be used to obtain the ideal braking distance at each eddy current braking level. The method of comparing each distance one by one in S103 is merely an example, and the determination of the first or second designated parking location on the route as the target parking location through comparison is merely an example and not a limitation.

[0111] S203: Obtain an ideal braking level by comparing the ideal braking distance with the target braking distance.

[0112] The target distance is the distance between the braking starting point and the target parking position.

[0113] One implementation of S203 can refer to the method of traversing and comparing distances to obtain the ideal braking level in S104. It is understandable that in addition to the method described in S104, other methods can also be used, for example, in descending order of eddy current levels.

[0114] S204: Obtain the corresponding relationship between the distance and speed of the train during the ideal braking process.

[0115] An implementation of S203 can refer to the calculation method of S105 for the cases of braking at ideal braking levels k and k-1 respectively. Formulas (9) and (10) in S105 are only examples. The method for obtaining the switching timing can refer to S104.

[0116] S205 : Obtain a control variable based on a difference between the operating positions during the ideal braking process and the actual braking process.

[0117] It is understood that the running position during the ideal braking process is obtained based on the corresponding relationship between the distance and the speed during the ideal braking process. The method for obtaining the running position during the actual braking process can be seen in formula (13).

[0118] An implementation of S205 can be found in S106-S109. The methods for obtaining the actual braking force and the actual distance traveled during braking, the difference being the difference (ie, error) and the change in the difference (eg, rate of change), and the fuzzy control method are merely examples.

[0119] S206: Based on the control amount and the ideal braking level, obtain the actual eddy current braking level used by the train.

[0120] An implementation of S206 may refer to S110 .

[0121] The method described in this embodiment takes into account the impact of track gradient on the braking process when calculating the train's ideal braking distance and determines the ideal eddy current braking level and its switching timing. This allows the train to safely and reliably stop at the designated stopping position even on long or steep slopes during braking, making the train's eddy current braking system more reliable.

[0122] An embodiment of the present application further provides a device for selecting an eddy current braking level, as shown in FIG4 , comprising: a first acquisition module, a second acquisition module, a third acquisition module, a fourth acquisition module and a control module.

[0123] Among them, the first acquisition module is used to obtain the ideal braking distance corresponding to each eddy current braking level based on the force parameters of the train during the braking process. The force parameters include: the gravity component caused by the slope of the road in the train's running route.

[0124] The second acquisition module is used to acquire the target parking position of the train based on the ideal braking distance at each eddy current braking level and the braking starting point.

[0125] The third acquisition module is configured to acquire an ideal braking level by comparing the ideal braking distance with a target braking distance, where the target distance is the distance between the braking starting point and the target parking position.

[0126] The fourth acquisition module is used to obtain the corresponding relationship between the distance and speed of the train during the ideal braking process, where the ideal braking process is a process of braking using the ideal braking level.

[0127] The control module is used to obtain a control amount based on the difference between the ideal braking distance and the actual braking distance at the ideal braking level, and to obtain an actual eddy current braking level used by the train based on the control amount and the ideal braking level.

[0128] The eddy current braking level obtained by the device described in this embodiment enables the train to stop at a designated parking position more accurately in emergency braking situations.

[0129] If the functions described in the method of the embodiment of the present application are implemented in the form of a software functional unit and sold or used as an independent product, they can be stored in a storage medium readable by a computing device. Based on this understanding, the part of the embodiment of the present application that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for enabling a computing device (which can be a personal computer, server, mobile computing device or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0130] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

Claims

1. A method for selecting an eddy current braking level, characterized in that: include: Based on the force parameters of the train during braking, the ideal braking distance corresponding to each eddy current braking level is obtained, wherein the force parameters include: the gravity component caused by the slope of the road in the running line of the train; Based on the ideal braking distance at each eddy current braking level and the braking starting point, a target parking position of the train is obtained; By comparing the ideal braking distance with the target braking distance, an ideal braking level is obtained, wherein the target distance is the distance between the braking starting point and the target parking position; Obtaining a corresponding relationship between the distance and the speed of the train during an ideal braking process, wherein the ideal braking process is a process of braking using the ideal braking level; Obtaining a control amount based on a difference between the operating positions during the ideal braking process and the actual braking process; Based on the control amount and the ideal braking level, an actual eddy current braking level used by the train is obtained.

2. The method according to claim 1, characterized in that The step of obtaining the target parking position of the train based on the ideal braking distance at each eddy current braking level and the braking starting point includes: If the distance between the braking starting point and the first preset parking position ahead of the train is less than a distance threshold, the second preset parking position ahead of the train is used as the target parking position, and the distance threshold is an ideal braking distance corresponding to the eddy current braking level with the maximum braking force; If the distance between the braking starting point and the first preset parking position is greater than the distance threshold, the first preset parking position is used as the target parking position.

3. The method according to claim 1, characterized in that The obtaining of the ideal braking level by comparing the ideal braking distance with the target braking distance includes: In the process of traversing the eddy current braking levels in a preset order, the first traversed eddy current braking level k that meets the conditions and the previous eddy current braking level k-1 of the first traversed eddy current braking level that meets the conditions are taken as the ideal braking levels, and the preset order is the order of the corresponding eddy current braking forces from low to high, and the condition includes that the corresponding ideal braking distance is less than the target braking distance.

4. The method according to claim 3, characterized in that The obtaining of the correspondence between the distance and the speed of the train during the ideal braking process includes: Obtaining a switching timing from the ideal braking level k to the ideal braking level k-1; Based on the switching timing, the initial speed at the start of braking, the time experienced by the ideal braking process, and the ideal braking force under the ideal braking level, the corresponding relationship between the distance and the speed in the ideal braking process is obtained.

5. The method according to claim 4, characterized in that The obtaining of a switching timing from the ideal braking level k to the ideal braking level k-1 includes: Acquire the distance between each position and the target parking position during braking at the ideal braking level k; Find a distance in the distance that is equal to the reference braking distance to obtain a target distance, wherein the reference braking distance is a braking distance obtained when the train takes the speed at the target distance as the initial speed under the ideal braking level k-1; The time corresponding to the target distance is used as the switching opportunity.

6. The method according to claim 4, characterized in that The obtaining, based on the control amount and the ideal braking level, an actual eddy current braking level used by the train comprises: Before the switching opportunity, the actual eddy current braking level is the sum of the ideal braking level k and the control amount, and after the switching opportunity, the actual eddy current braking level is the sum of the ideal braking level k-1 and the control amount.

7. The method according to claim 1, characterized in that The gravity component force caused by the slope of the road in the running route of the train is obtained based on the mass of the train and the slope, where the slope is the angle between the slope in the running route and the horizontal plane.

8. A device for selecting eddy current braking level, characterized in that: include: A first acquisition module is used to acquire an ideal braking distance corresponding to each eddy current braking level based on a force parameter of the train during braking, wherein the force parameter includes: a gravity component force caused by a slope of a road in a running route of the train; A second acquisition module is used to acquire a target parking position of the train based on an ideal braking distance at each eddy current braking level and a braking starting point; A third acquisition module, configured to acquire an ideal braking level by comparing the ideal braking distance with a target braking distance, wherein the target distance is a distance between the braking starting point and the target parking position; a fourth acquisition module, configured to acquire a correspondence between a distance and a speed of the train during an ideal braking process, wherein the ideal braking process is a process of braking using the ideal braking level; The control module is used to obtain a control amount based on the difference between the running positions during the ideal braking process and the actual braking process, and to obtain an actual eddy current braking level used by the train based on the control amount and the ideal braking level.

9. A controller, characterized in that: include: Memory for storing computer programs; A processor is used to implement the method for selecting the eddy current braking level according to any one of claims 1 to 7 by running the computer program.

10. A readable storage medium, characterized in that: When the instructions in the readable storage medium are executed by a processor of an electronic device, the electronic device is enabled to execute the method for selecting the eddy current braking level according to any one of claims 1 to 7.

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