A petri net-based railway station continuation route protection system and site deployment method

Abstract

The present application belongs to the technical field of high-speed railway extension route safety protection, and particularly relates to a railway station extension route protection system based on Petri net and a station deployment method. The technical scheme of the present application introduces the method of discrete event system modeling, adopts Petri net modeling for the protection of extension route by formal verification, establishes the corresponding extension route protection resource allocation constraint model, and adopts the method of formal verification to verify the safety of train operation. The technical scheme of the present application can check the safety of the arrangement of extension route in the station, can report errors for the unfeasible extension route arrangement through the meaning of the marked fault library, and can give the feasible alternative scheme, thereby improving the safety of train extension route protection and ensuring the safe operation of trains in the station.

Description

Technical Field

[0001] This invention belongs to the field of high-speed railway continuous route safety protection technology, and specifically relates to a railway station continuous route protection system and station deployment method based on Petri net. Background Technology

[0002] A route is the physical path taken by a train or shunting train from a designated starting point to a designated ending point on a railway. Different switches along the route must be operated to designated positions. The beginning and end of the route are defined by signals, warning markers, stop markers, or station boundary markers. The beginning of the route, i.e., the entry point of the train or shunting train, must be protected by signals to ensure the safe operation of the train or shunting train. The path taken by a train is called a train route. Based on its nature, it can be further subdivided into receiving routes, departure routes, through routes, and transfer routes. These are protected by station entry, station exit, and route signals, respectively. The path taken by a shunting train is called a shunting route, protected by shunting signals. Based on the relationship between interlocking concepts and routes, there are also parallel routes, opposing routes, detour routes, basic routes, forward overlapping routes, continuous routes, pushing routes, and shunting routes.

[0003] A continuation route is a type of route. In the light strip display, the continuation route immediately follows the end of the receiving route, forming a continuous light strip. According to the "Computer Interlocking Technical Conditions" (TB / T 3027—2015), stations with a downhill gradient exceeding 6‰ within the braking distance outside the entrance signal must have a continuation route at the end of the receiving route. When a safety line or separating device is present at the end of the receiving route, the continuation route leads towards the safety line or separating device. When there is no safety line or separating device at the end of the receiving route, the continuation route leads towards the main line.

[0004] Chinese trains can brake to a stop under various common conditions. However, the greater the downward gradient, the longer the braking distance required. If the receiving route has a greater downward gradient, the train may not be able to stop and may encroach on another bottleneck area. If a train happens to be passing in the opposite direction at this time, a collision may occur. Therefore, the design of the continuation route is directly related to traffic safety. Summary of the Invention

[0005] The purpose of this invention is to improve the safety of high-speed railway train operation. Using Petri nets as a tool, a corresponding resource allocation constraint model for continuous route protection is established, forming a Petri net-based continuous route protection system for railway stations with downhill gradients of at least 6‰. This system uses formal verification methods to verify train operation safety. The safety of continuous route arrangements within the station is checked, and by understanding the meaning of the marked fault locations, infeasible continuous route arrangements can be flagged, thus improving the safety of train continuous route protection and ensuring the safe operation of trains within the station.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A railway station route continuation protection system based on Petri nets is disclosed. This system comprises a comprehensive model consisting of a 0.6% downhill slope protection model and a route continuation protection fault diagnosis model. In the Petri net model, the transition delay corresponds to the train departure time from the clearing section, the depot corresponds to the track section of the railway station, and the token corresponds to the railway train. The railway station route continuation protection system is established according to the up and down directions of the target railway station and can dynamically simulate train reception route events at the target railway station. The 0.6% downhill slope protection model is used to simulate the train reception route process within the station's track section, and the route continuation protection fault diagnosis model is used to report errors for infeasible train reception route events and provide feasible alternatives.

[0008] To address the issue of safety protection for continuous routes, this invention introduces a modeling method for discrete event systems. Formal verification is used to model the protection of continuous routes using Petri nets, establishing a corresponding resource allocation constraint model for continuous route protection. Formal verification is then employed to verify train operation safety. The technical solution of this application can verify the safety of continuous route arrangements within a station. By understanding the meaning of the marked fault locations, infeasible continuous route arrangements can be flagged, improving the safety of train continuous route protection and ensuring the safe operation of trains within the station.

[0009] Preferably, the train station used to establish the Petri net model is a standard four-track station, which includes a double-track, two-way main line; namely, track 1G and track IIG, with track 1G in the downhill direction and track IIG in the uphill direction. The uphill direction is provided with a downhill slope of more than 0.6%. Each end of the track is provided with two sections. Track 1G is sequentially named IAG, IDG, 1G, 4DG, and IBG in the downhill direction; track IIG is sequentially named IIBG, 2DG, IIG, 3DG, and IIAG in the uphill direction. The four-track station also includes track 3G and track 4G, which are arranged parallel to the main line. The two ends of track 3G merge into the main line through sections IDG and 4DG, respectively, and the two ends of track 4G merge into the main line through sections 2DG and 3DG, respectively.

[0010] Preferably, the Petri net is defined as follows:

[0011] Let the time-delayed Petri net be PN = {P, T, Pre, Post}; the set of places of the Petri net be P = {p1, p2, p3, p4}, and its transition set be T = {t1, t2, t3, t4, t5}.

[0012] Preferably, the transition emission process is the same as the Token emission process, wherein the initial identifier is defined by the following formula:

[0013] M0=[M0(p1) M0(p2) M0(p3) M0(p4)] T =[1 0 0 0] T (1-1)

[0014] Transition emission conditions: A transition is only allowed to occur when the total number of input place identifiers is greater than or equal to the weight of the arc from the place to the corresponding transition. At this time, the transition is considered to be enabled. Whether an enabled transition will be emitted depends on whether the event actually occurs.

[0015] The detailed rules for transition enabling are as follows:

[0016] Definition 1: A transition t∈T is defined if and only if: M( p When M≥Pre(·,t), t is said to be enabled under the identifier M.

[0017] Definition 2: If, under the condition of M, a transition t is emittable, then after the emission of transition t, Pre(p,t) tokens are removed from the input places p∈P, and Post(p,t) tokens are added to the output places p∈P. If, under the condition of M, the new label after the emission of t becomes M', then...

[0018]

[0019] Equation (1-2) is the state equation for the place p. It is an n-dimensional emission vector.

[0020] The entire process described above can be represented by M[t>M'], which can be interpreted as triggering t at point M. j The result is then labeled M'. These symbols can be extended to a series of transitions. Pre(p,t) is not equal to zero if and only if p∈·t, and Post(p,t)≠0 if and only if p∈·t. That is, after emission t, Pre(p,t) tokens are removed from all participating input collections p, and Post(p,t) tokens are added to all participating output collections p. The conditions given in Definition 1 guarantee the non-negativity of the symbols.

[0021] If transition t2 is transmitted, the network will reach a new identifier because the transmission t2 removes one token from p1 and adds two tokens to p2. The reachability identifier at this point is:

[0022] M1=[M1(p1) M1(p2) M1(p3) M1(p4)] T =[0 2 0 0] T (1-3)

[0023] Preferably, in the railway station continuous route protection system, the depots and their changes are shown in the following table:

[0024]

[0025] The 0.6% downhill slope protection model includes an uphill train reception route model and a downhill train reception route model: taking the uphill train reception route of train A on track IG as an example, track IG starts from section IBG, passes through section 4DG, and arrives at track IG. The continued route considers sections 1DG and IAG. Before the uphill train reception route on track IG, it must be ensured that sections IBG, 4DG, and track IG are in an idle state, and that sections 1DG and IAG are also idle.

[0026] When the locations of segments IBG, 4DG, 1DG, IAG, and IG are all marked by Token, the transition t occurs. sI Enable and take away their tokens, while sending a token to the custodian. I-begin This indicates that train A has started receiving trains on track IG in the upward direction. Train A is running on section IBG. At this time, other train routes are not allowed to declare and use the resources of section IBG, section 4DG, section 1DG, section IAG, and track IG. Only after train A has completed receiving trains and released the ownership of these resources can other trains be allowed to use these resources.

[0027] The procedure for receiving trains in the downward direction of track IG is as follows: a train receiving route in the downward direction of IG can only be declared when section 1DG, section IAG, and track IG are idle.

[0028] The preferred physical meanings of locations and transitions in the continuous route protection fault diagnosis model are shown in the table below:

[0029]

[0030] Explanation of the situation where train A wants to take a connecting route on track IG in the upward direction, while simultaneously wanting to take a connecting route on track 3G in the downward direction: The connecting route on track IG in the upward direction begins at warehouse s. IAt this point, all locations IBG, 4DG, 1DG, IAG, and IG are marked, and transition t... sI Enable and take away the tokens from the kusuo, while simultaneously launching a token to the kusuo S. I-begin This indicates that train A has started its receiving route on track IG in the upward direction. If depot x3 is marked at this time, it means that other trains want to receive trains on track 3G in the downward direction. Since 1DG and IAG are not marked, the transition t is... x3 The enabling condition is not met, and transition t is then... e5 Enable, and simultaneously send a token to the faulty storage p while taking away the token from storage x3. e5 Fault alarm, and based on the fault database p e5 The meaning of the marking identifies the problem, and at the same time, feasible solutions are proposed to correct the problem.

[0031] More specifically, the change t e5 and t x3 All delays are 0, and transition t is defined. e5 For low transmit priority, that is, when both are enabled simultaneously, transition t x3 emission.

[0032] A site deployment method for a railway station continuation route protection system based on Petri nets, characterized by comprising the following steps:

[0033] Step 1: Determine the target railway station and its train operation information. Based on the track and section structure of the target railway station and the train operation information, establish a comprehensive simulation model of railway station continuation routes based on Petri nets.

[0034] Step 2: Perform simulation verification of the actual operation plan on the model; debug the target station integrated model according to the simulation verification results. If the preset fault locations in the integrated model are consistent with the preset problems in the simulation verification process, it indicates that the target station integrated model is qualified.

[0035] Step 3: Apply the comprehensive model of the target station to the dynamic process of the train receiving route of the corresponding target station to protect the railway station interlocking route protection system.

[0036] Furthermore, step 2 specifically includes the following steps:

[0037] Step 2.1, Data preparation: Name the in-station scheduling plans of the target station respectively, and preset the fault part in the models of the uplink and downlink directions respectively;

[0038] Step 2.2, Feasibility verification: Use model simulation to verify the station scheduling plan obtained, and check whether it contains marked faulty storage areas;

[0039] Step 2.3: Calculate the reachability map of the model, observe only the fault locations, and select the reachability markers that are not zero; observe the calculation results of the reachability markers to see if the fault locations are not zero under each reachability marker.

[0040] Step 2.4, Result Analysis: The reachability identification results can be used to locate the identified faulty locations. Based on the meaning of the marking of the faulty location, the cause of the problem can be identified, and the corresponding operation plan can be adjusted.

[0041] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0042] 1. In the technical solution of this application, Petri nets are applied to the protection of extended routes on downhill slopes greater than 6‰. Petri net modeling and simulation verification are combined to further improve the safety of extended route protection. In this technical solution, a Petri net protection model corresponding to the extended route of a commonly used four-track station is established. This model considers the resource allocation problem under the extended route, and can not only verify the feasibility of all train operation plans within the example station, but also provide a reference for other stations. Simulation verification of the station model can calculate the feasibility of the station's scheduling plan. If it is infeasible, the problematic part can be located and resolved. This greatly improves the safety of train operation control within the station. Attached Figure Description

[0043] Figure 1 This is an example model of a Petri net;

[0044] Figure 2 (a) is a schematic diagram of the initial state of the Petri net. Figure 2 (b) is a schematic diagram of the transition state of the Petri net after transmission;

[0045] Figure 3 This is a schematic diagram of the site plan of an example station;

[0046] Figure 4 Based on Figure 3 The example station establishes a Petri net model. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings.

[0048] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0049] Example 1

[0050] To address the safety protection issue of extended routes, this invention introduces a modeling method for discrete event systems. Formal verification is used to model the protection of extended routes using Petri nets, establishing a corresponding resource allocation constraint model for extended route protection. Train operation safety is then verified through formal verification. This embodiment provides a Petri net-based railway station extended route protection system, comprising a comprehensive model consisting of a 0.6% downhill slope protection model and an extended route protection fault diagnosis model.

[0051] In the Petri net model, the transition delay corresponds to the time of train departure from the clearing section, the depot corresponds to the track section of the railway station, and the token corresponds to the railway train. The railway station continuation route protection system is established according to the up and down running directions of the target railway station, and can dynamically simulate the train receiving route event at the target railway station. The 0.6% downhill slope protection model is used to simulate the train receiving route process in the track section within the station, and the continuation route protection fault diagnosis model is used to report errors for train receiving route events that are not feasible according to the train plan and provide feasible alternative solutions.

[0052] The protection system of this solution can check the safety of the continuous route arrangement within the station. By using the meaning of the marked fault database, it can report errors for infeasible continuous route arrangements, thereby improving the safety of train continuous route protection and ensuring the safe operation of trains within the station.

[0053] First, the basic structure of a Petri net is given: as follows Figure 1 The example model is shown below.

[0054] for Figure 1 In a Petri net, PN = {P, T, Pre, Post}, the set of places of the Petri net is P = {p1, p2, p3, p4}, and its transition set is T = {t1, t2, t3, t4, t5}.

[0055] The operating rules of Petri nets are as follows: the process of launching a transition is the process of launching a token, that is, using transitions to change the number of tokens in the place.

[0056] Specifically, Figure 2 In the figure, (a) and (b) are the initial state of the Petri net system and the state after transition t2 is transmitted, respectively. Figure 2 In (a), the initial identifier is

[0057] M0=[M0(p1) M0(p2) M0(p3) M0(p4)] T =[1 0 0 0] T (1-1)

[0058] Transition emission conditions: A transition is considered enabled only when the total number of input place identifiers is greater than or equal to the weight of the arc from that place to the corresponding transition. Whether an enabled transition will be emitted depends on whether the event actually occurs.

[0059] The detailed rules for transition enabling are as follows:

[0060] Definition 1: A transition t∈T is defined if and only if: M( p When M≥Pre(·,t), t is said to be enabled under the identifier M.

[0061] Definition 2: If, under the condition of M, a transition t is emittable, then after the emittance of transition t, Pre(p,t) tokens are removed from the input places p∈P, and Post(p,t) tokens are added to the output places p∈P. If, under the condition of M, the new label after the emittance of t becomes M', then...

[0062]

[0063] (1-2) is the state equation of the place p. It is an n-dimensional emission vector.

[0064] The entire process can be represented by M[t>M', which means that t is triggered at point M. j The result is then labeled M'. These symbols can be extended to a series of transitions. Pre(p,t) is not equal to zero if and only if p∈·t, and Post(p,t)≠0 if and only if p∈·t. In simpler terms, after emission t, Pre(p,t) tokens are removed from all participating input pools p, and Post(p,t) tokens are added to all participating output pools p. The conditions given in Definition 1 guarantee the non-negativity of the symbols.

[0065] Combination Figure 2 In the network structure shown in (a), if transition t2 is emitted, the network will reach the following state: Figure 2 The new identifier shown in (b) is as follows: because the emission of t2 removes one token from p1 and adds two tokens to p2, the reachability identifier is now:

[0066] M1=[M1(p1) M1(p2) M1(p3) M1(p4)] T =[0 2 0 0] T (1-3)

[0067] The following explanation uses a four-track station as an example: Figure 3The image shows a simplified version of a double-track, two-way automatic block signaling station on a high-speed railway line, retaining only the track sections and turnouts. In the image, the thick lines represent the main line, the solid lines represent the down direction, and the dashed lines represent the up direction.

[0068] The train stations used to build the Petri net model are four-track stations, such as... Figure 3 As shown, the four-track station includes a double-track, two-way main line; namely, track 1G and track IIG, with track 1G in the downhill direction and track IIG in the uphill direction. The uphill direction is provided with a downhill slope of more than 0.6%. Each end of the track is provided with two sections. Track 1G is, in descending order, section IAG, section IDG, track 1G, section 4DG, and section IBG; track IIG is, in ascending order, section IIBG, section 2DG, track IIG, section 3DG, and section IIAG. The four-track station also includes track 3G and track 4G, which are set parallel to the main line. The two ends of track 3G merge into the main line through section IDG and section 4DG, respectively, and the two ends of track 4G merge into the main line through section 2DG and section 3DG, respectively.

[0069] Figure 3 In the example station, IG and IIG represent the main tracks for the down and up directions of the double-track section, respectively. DG indicates a turnout section, AG indicates a down throat section without turnouts, and BG indicates an up throat section without turnouts. Turnouts have two different states: 1 and 2. The arrangement of different routes determines the state of different turnouts. For example, for the down direction 3G receiving route, turnout #1 in turnout section 1DG must be in the 2.5-5 position to receive a train.

[0070] Article 286 of the "Railway Technical Management Regulations" stipulates that: within the braking distance of the station entrance signal, if the entrance direction is a downhill slope exceeding 6‰, and there is no separating device at the end of the receiving track, simultaneous receiving of trains in opposite directions and simultaneous departure and arrival of trains in the same direction are prohibited (except for sections where only EMU trains operate). In the scheme of this application, ... Figure 3 The slope exceeds 6‰ within the braking distance outside the throat entry signal of the middle and upper direction. Therefore, it is necessary to design a continuation route at the end of the receiving route in the upper direction to prevent the train from slipping and causing danger.

[0071] Table 1 shows the interlocking table for the continuation routes established for the example station. It can be seen that there are 4 continuation routes, all of which are continuations in the downlink throat.

[0072] Table 1 Example Station Continuation Route Interlocking Table

[0073]

[0074] When no separating device is installed at the end of the receiving track, and trains in opposite directions are simultaneously receiving each other, a train collision may occur. Interlocking tables are a traditional method for protecting against continuation routes. This paper uses Petri net modeling for a sample station's continuation route to achieve protection of the continuation route and improve the safety of train operation within the station. It provides a new approach and method for verifying the safety of station interlocking continuation routes.

[0075] This application uses a time-delay Petri net model, assigning delays to transitions, with each transition's delay corresponding to the time of train clearance from the designated section. In this application, the places, transition delays, and tokens in the Petri net correspond to the track section, the time of train clearance for the corresponding track section, and the train itself, respectively. These three elements are used to dynamically simulate and formally verify the planned train operation within the station. This provides a new protection method for station interlocking routes.

[0076] Specifically, the transition rules for the 0.6% downhill slope protection model are as follows:

[0077] Combination Figure 3 Explanation:

[0078] The model uses a thick solid line as the dividing line, with the left side representing the receiving routes in the upward direction and the right side representing the receiving routes in the downward direction. The meanings of key locations and transitions in the model are shown in Table 2. Route arrangement is a resource allocation process. Taking the receiving route in the upward direction of IG as an example, this route's resources begin at section IBG and 4DG, and end at track IG. However, due to the existence of a 0.6% downhill slope, continuation routes need to be considered when arranging routes. That is, before declaring the receiving route in the upward direction of IG, it is necessary to ensure that not only sections IBG and 4DG and track IG are idle, but also sections 1DG and IAG are idle. After confirming that all sections are idle, the declaration of the receiving route in the upward direction of IG is completed, reflected in the model as transition t. sI Enable and remove tokens from the storage locations of segments IBG, 4DG, 1DG, IAG, and IG, while simultaneously sending a token to storage location s. I-begin This indicates the start of an IG (Incoming Train Attachment) route in the upward direction, with the train running on section IBG. At this point, other routes are not allowed to declare and use resources such as IBG, 4DG, 1DG, IAG, and track IG because the tokens in their storage spaces are not marked, meaning they lack "rights." Only after a receiving route completes and releases the rights to these resources can other routes use them. Otherwise, train conflicts will occur. Therefore, routes need to be established and unlocked in a specific order. A route is only allowed to be established when all the resources required for its creation are unlocked; otherwise, unsafe route arrangements will result.

[0079] like Figure 4 The image shown is based on Figure 3 The model established by the example site. Figure 4 In the model, the right side of the vertical solid line represents the receiving route in the downhill direction. Both sides are based on the same model, sharing track sections and resources such as tracks. However, the receiving route in the downhill direction does not involve a 0.6% downhill slope, so there is no issue of continuing the route. Taking the receiving route in the downhill direction of IG as an example, according to railway specifications, the receiving route in the downhill direction of IG can only be declared when 1DG, IAG, and track IG are idle. If 1DG and IAG are declared for use due to continuing the route, even though 1DG and IAG are idle, they still cannot be used by other routes. This is reflected in the model as the tokens in their storage places being taken away, thus preventing the receiving route in the downhill direction of IG from being implemented.

[0080] Table 2 shows the meaning of key locations / changes in the model.

[0081]

[0082]

[0083] Furthermore, the logic of the continuation route protection fault diagnosis model is as follows:

[0084] A fault alarm system alerts the system to potential faults and risks. For a route, a fault alarm system is not needed during planned operation. However, a fault diagnosis system becomes essential if unforeseen circumstances arise during route execution, preventing adherence to the plan or even causing conflicts. In the technical solution of this application, the fault diagnosis model can protect against potential hazards before route planning is implemented. By outputting hazard information based on the marked conditions in the fault database, it significantly improves the safety of train operation at stations, especially regarding the often overlooked issue of protection on downhill slopes with a gradient of 0.6%. Taking the IG downhill receiving route as an example, when a train wants to establish a receiving route, it first checks whether the relevant track sections are free. If IBG, 4DG, and IG are all unlocked, and IAG and IDG are free, the possession rights of these track sections are revoked after the departure route is declared. Finally, the relevant track sections are sequentially occupied, cleared, and unlocked until the receiving route is completed, at which point the possession rights are returned sequentially. However, if the train needs to establish a downlink receiving route for 3G simultaneously as planned, the occupancy rights of IAG and IDG are taken away. Regardless of whether it is due to a fault or improper scheduling, our downlink receiving route for 3G cannot proceed as originally planned. The model in this application needs to report the fault.

[0085] Fault diagnosis model corresponds to Figure 4The dashed lines on the model need to be used in conjunction with the 0.6% downhill slope protection model, and fault diagnosis should be performed in conjunction with the physical meaning of the depot. For the situation where a train receiving route in the uphill direction of track IG needs to be implemented, and a train receiving route in the downhill direction of track 3G is desired, the train receiving route in the uphill direction of track IG starts at depot s. I If all locations IBG, 4DG, 1DG, IAG, and IG are marked, then transition t sI Enable and take away the tokens from the kusuo, while simultaneously launching a token to the kusuo. I-begin This indicates that the upward direction of stock IG has begun. At this time, warehouse x3 is marked, indicating a desired downward direction of stock 3G. However, since 1DG and IAG are not marked, the transition t... x3 The enabling condition is not met, and transition t is then... e5 Enable, and simultaneously send a token to the faulty storage p while taking away the token from storage x3. e5 At this time, a fault alarm is triggered, and based on the fault database... e5 The marked meanings pinpoint the problem, and modifications are made accordingly. It's necessary to add the transition t. e5 and t x3 Although the delays are all 0, the transition t e5 It has a lower launch priority, meaning that the transition t is only active when both are enabled simultaneously. x3 Launch. The meanings of the tags in the relevant fault database are shown in Table 3 below.

[0086] Table 3. Meaning of Location / Change in Fault Diagnosis Model

[0087]

[0088] Example 2

[0089] This embodiment provides a site deployment method for the above-described Petri net-based railway station continuous route protection system, specifically including the following steps:

[0090] Step 1: Determine the target railway station and its train operation information. Based on the track and section structure of the target railway station and the train operation information, establish a comprehensive simulation model of railway station continuation routes based on Petri nets.

[0091] Step 2: Perform simulation verification of the actual operation plan on the model; debug the target station integrated model according to the simulation verification results. If the preset fault locations in the integrated model are consistent with the preset problems in the simulation verification process, it indicates that the target station integrated model is qualified.

[0092] Step 3: Apply the comprehensive model of the target station to the dynamic process of the train receiving route of the corresponding target station to protect the railway station interlocking route protection system.

[0093] More specifically, the simulation verification method for step 2 is as follows:

[0094] In the technical solution of this application, a preset verification method is adopted. A train station operation plan with a preset failure is given as shown in Table 4. The delay is corresponding to the transition in the model. The Petri net simulation verification tool TINA is used to perform simulation verification. If the output failure is consistent with the preset problem, it means that the model is feasible and has application value.

[0095] Table 4 Train Operation Plan within the Station

[0096]

[0097] The specific operating procedure is as follows: First, it is stipulated that the clearing time for each track section in this application is 30 seconds, meaning the train's running time in all sections is 30 seconds. The station train scheduling plan given in Table 4 involves a total of 6 trains, named sequentially as (Train 01, Train 02, Train 03, Train 04, Train 05, Train 06). Two trains are in the down direction, namely Train 01 and Train 02. Four trains are in the up direction, namely Train 03, Train 04, Train 05, and Train 06. Their stopping tracks, stopping times, and departure times within the station are shown in Table 4.

[0098] The dwell time is added to the track clearing time. For example, if IG and IIG trains cannot stop, the difference between their arrival and departure times is the time it takes for the train to clear the track. For train 01, the difference between its 3G arrival and departure times is 2 minutes and 30 seconds. The dwell time excluding the track clearing time is 2 minutes. This application pre-defines fault sections in both the up and down directions and uses model simulation to verify whether the corresponding fault database is marked in the given station scheduling plan.

[0099] In converting the train operation plan into the delay of each transition in the model, this application uses 30 seconds as a unit of time. Therefore, the transition delay of the train clearing the track is 30 / 30 = 1 unit of time, and the time to clear 1DG is 1 unit of time. Similarly, the transition delay corresponding to the clearing time of other tracks can also be calculated as 1 unit of time.

[0100] The arrival times of cars 01, 02, 03, and 05 are used as the time baseline. The difference between the arrival times of the remaining trains and the time baseline is first calculated using the unit time calculation method and then added to the transition delay connected to the train arrival depot, so that the difference in departure times can be reflected in the model.

[0101] The clearing time of each track segment is mapped one-to-one with the corresponding transition delay, and assigned to... Figure 2 In the model, the initial identifier M0 of the fault database of the network structure is [p e1 ,p e2 ,p e3 ,p e4 ,p e5 ,p e6 ,p e7 ,p e8 Since none of the fault locations are marked in the initial state, M0 = 0. The model can now be simulated and verified. Using the time-delay Petri net simulation software TINA, the reachability graph in the model is calculated. Only the fault locations are observed, and the reachability markers that are not zero are selected.

[0102] By observing the calculation results of the reachability indicators, we can see that the fault database is not zero under each reachability indicator, as shown in Table 5 below:

[0103] Table 5 shows the calculated reachability indicators.

[0104]

[0105] By observing the reachability calculation results shown in Table 5, it can be seen that the fault database has p e2 and p e3 The fault codes are marked. It is known that the given station scheduling plan is infeasible. Then, based on the meanings of the marked codes in Table 3, the problem can be located as the receiving routes for cars IG and IIG in the uphill direction cannot proceed as planned. The corresponding operation plan needs to be adjusted. The adjusted train operation plan is shown in Table 6. The main adjustment is to the receiving routes of cars 03 and 05. The modified delays are then assigned to the model for verification to confirm that the operation plan is feasible.

[0106] Table 6. Revised Feasible Train Scheduling Plans within the Station

[0107]

[0108] In this application's technical solution, Petri nets are applied to the protection of extended routes on downhill slopes greater than 6‰. Petri net modeling and simulation verification are combined to further improve the safety of extended route protection. The solution utilizes a common four-track station and establishes a Petri net protection model corresponding to the extended route. This model considers resource allocation under extended routes, allowing for feasibility verification of all train operation plans within the example station and providing a reference for other stations. Simulation verification of the station model calculates the feasibility of the station's scheduling plan; if infeasibility is found, the problematic parts can be located and resolved. This significantly improves the safety of train operation control within the station.

Claims

1. A railway station continuous route protection system based on Petri nets, characterized in that, The railway station continuous route protection system includes a comprehensive model consisting of a 0.6% downhill slope protection model and a continuous route protection fault diagnosis model. In the Petri net model, the transition delay corresponds to the time of train exiting the clearing section, the depot corresponds to the track section of the railway station, and the token corresponds to the railway train. The railway station continuation route protection system is established according to the up and down directions of the target railway station; and it can dynamically simulate the train receiving route event at the target railway station. The 0.6% downhill slope protection model is used to simulate the train receiving route process in the track section within the station. The continuous route protection fault diagnosis model is used to report errors for train receiving route events that are not feasible according to the train plan and to provide feasible alternative solutions. The train station used to build the Petri net model is a four-track station, which includes a double-track, two-way main line; namely, track 1G and track IIG, with track 1G representing the downhill direction and track IIG representing the uphill direction. The uphill direction is equipped with a downhill slope of more than 0.6%. Each track has two sections at each end. Among them, the 1G section is divided into the following segments according to the downward direction: IAG, IDG, 1G, 4DG, and IBG. According to the upward direction, the IIG (Industry IIG) is divided into Segment IIBG, Segment 2DG, IIG, Segment 3DG, and Segment IIAG. The four-track station also includes track 3G and track 4G, which are set up in parallel with the main line. The two ends of track 3G merge into the main line through section IDG and section 4DG respectively, and the two ends of track 4G merge into the main line through section 2DG and section 3DG respectively. The 0.6% downhill slope protection model includes an uphill vehicle reception route model and a downhill vehicle reception route model: Taking the train A receiving route on track IG in the upward direction as an example, track IG starts from section IBG, passes through section 4DG, and arrives at track IG. The continued route considers sections 1DG and IAG. Before taking the train route in the upward direction of the IG lane, ensure that the IBG, 4DG and IG lanes are in an idle state, and ensure that the 1DG and IAG lanes are also idle. When the locations of segments IBG, 4DG, 1DG, IAG, and IG are all marked by Token, the transition t occurs. sI Enable and take away their tokens, while sending a token to the custodian. I-begin This indicates that train A has begun its receiving route on track IG in the upward direction. The procedure for receiving trains in the downward direction of track IG is as follows: a receiving train route in the downward direction of IG can only be declared when section 1DG, section IAG and track IG are free. Explanation of the situation where train A wants to take a connecting route on track IG in the upward direction, while simultaneously wanting to take a connecting route on track 3G in the downward direction: The upward trend of the stock IG line begins at the warehouse. s I At this point, all locations IBG, 4DG, 1DG, IAG, and IG are marked, and transition t... sI Enable and remove the token from the kusuo, while simultaneously launching a token to the kusuo. I-begin This indicates that train A begins its receiving route on track IG in the upward direction. At this time, if the depot... x If 3 is marked, it means that other trains want to take the connecting route on track 3G in the down direction. Since 1DG and IAG are not marked, the transition t is... x3 The enabling condition is not met, and the transition occurs. t e5 Enable, take away the warehouse x At the same time, 3 tokens simultaneously send a token to the faulty warehouse. p e5 Fault alarm, and based on the fault database p e5 The meaning of the marking identifies the problem, and at the same time, feasible solutions are developed to correct the problem. change t e5 and changes t x3 All delays are 0, define transitions. t e5 For low transmit priority, the transition occurs when both are enabled simultaneously. t x3 emission.

2. The Petri net-based railway station continuous route protection system according to claim 1, characterized in that, The Petri net is defined as follows: Let the time-delay Petri net be: Petri nets are collections of data. Its changes are set as .

3. The Petri net-based railway station continuous route protection system according to claim 2, characterized in that, In the Petri net model, the transition emission process is the same as the Token emission process, where the initial identifier is given by the following formula: (Equation 1-1) The conditions for a transition to be emitted are as follows: a transition is only allowed to be emitted when the total number of input place identifiers is greater than or equal to the weight of the arc from the place to the corresponding transition. At this time, the transition is considered to be enabled. Whether an enabled transition will be emitted depends on whether the event actually occurs.

4. The Petri net-based railway station continuous route protection system according to claim 2, characterized in that, The detailed rules for transition enabling are as follows: Definition 1: A transition If and only if: ; When satisfied At that time, it was called In the logo The following is enabling; Definition 2: If in the identifier Under the condition of enabling, a change It can be launched and change. After launch ， From the input library Move to the middle A token, and to the output warehouse. Put into A token, if in under conditions The new logo after launch became ,but Among them, equation (1-2) represents the warehouse. The state equation, yes 3D emission vector.

5. The Petri net-based railway station continuous route protection system according to claim 4, characterized in that, The physical meanings of the depots and their changes involved in the railway station continuous route protection system are shown in the table below: 。 6. The Petri net-based railway station continuous route protection system according to claim 5, characterized in that, The physical meanings of storage locations and transitions in the continuous route protection fault diagnosis model are shown in the table below: 。 7. A site deployment method for a railway station continuous route protection system based on Petri nets according to any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Determine the target railway station and its train operation information. Based on the track and section structure of the target railway station and the train operation information, establish a comprehensive simulation model of railway station continuation routes based on Petri nets. Step 2: Perform simulation verification of the model based on the actual operation plan; adjust the target based on the simulation verification results. The station's integrated model, if the preset fault location in the integrated model is the same as the preset problem in the simulation verification process... To; This indicates that the target station's integrated model is qualified; Step 3: Apply the comprehensive model of the target station to the dynamic process of the train receiving route of the corresponding target station to protect the railway station interlocking route protection system.

8. The site deployment method for a railway station continuous route protection system based on Petri nets according to claim 7, characterized in that, Step 2 specifically includes the following steps: Step 2.1, Data Preparation: Name the internal scheduling plans of the target station separately, and in the uplink direction... The fault components are pre-set in the model for the downlink direction; Step 2.2, Feasibility Verification: The station scheduling plan obtained through model simulation is verified, and its details are examined. Does it contain a marked fault library? Step 2.3: Calculate the reachability graph of the model, observe only the fault locations, and select the reachability markers that are not zero; By observing the calculation results of the reachability identifiers, we can see that the fault database is not zero under each reachability identifier. Step 2.4, Result Analysis: The reachability marker calculation results can locate the identified faulty locations. Based on the meaning of the markers for these faulty locations, the cause of the problem can be determined, and corresponding operational plans can be adjusted. Adjustments were made.

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