Partial binary tree fair train dispatching system and method based on supervisory control theory

Abstract

The present invention discloses a partial binary tree fair train dispatching system and method based on supervisory control theory, which mainly solves the problem that the existing one-way, single-line, multi-platform station train entry and exit dispatching relies on the train timetable, and the platform and crossover capacity constraints require large calculations and high investment. The system includes entry and exit switch modules for simulating the train entry and exit process; platform capacity specification modules and crossover capacity specification modules for constraining platform and crossover capacity; fair dispatching specification modules for ensuring that the number of trains entering and exiting each platform is in a relatively balanced state; and dispatching priority specification modules for ensuring that the platform priority decreases as the platform number increases. Through the mutual cooperation of these modules, the present invention realizes the automatic constraint of platform and crossover capacity during the train entry and exit process, the relatively fair dispatch of each platform, and the first-in-first-out dispatching effect of trains. It does not need to be based on a timetable or distinguish between trains, and has low cost and low investment. It can be used for station management of train entry and exit.

Description

Technical Field

[0001] The present invention belongs to the technical field of railway transportation, and in particular relates to a partial binary tree fair train dispatching system, which can be used to optimize the dispatching of trains entering and leaving stations. Background Art

[0002] In recent years, China has made tremendous progress in transportation, particularly in railway construction. The railway industry, with its advantages of low energy consumption, large capacity, and wide coverage, is of great significance to various industries. Existing railway systems include single-track railways, such as the Qinghai-Tibet Railway and the Chengdu-Kunming Railway, and multi-track railways. Single-track railways present two major scheduling challenges: train scheduling on single-track railways with one direction, and train scheduling on single-track railways with bidirectional operation. To address the train scheduling problem on single-track railways with one direction, researchers have proposed numerous control algorithms, including branch and bound, Lagrangian relaxation, genetic algorithms, and heuristic algorithms. However, these algorithms consume significant computational cost and time to generate feasible paths. Determining the optimal feasible path requires designing new algorithms and constraints based on the calculated feasible paths, further increasing computational complexity. Furthermore, these algorithms cannot easily implement automated scheduling, such as platform-based fair scheduling and automatic capacity constraints.

[0003] Russian patent publication RU2757131C1 discloses a "method for controlling trains when leaving a station sequentially." The method involves the following steps: a first train departs from a first track at the station, and electrical equipment prepares for the departure of a second train from a second track at the station, timed to occur after the first train leaves the station's exit throat and enters the subsequent track section. Simultaneously, the station's radio control center sends a command to the second train via a radio channel, switching the second train's onboard control equipment from train mode to shunting mode or a similar control mode. This mode remains in effect until the second train approaches designated coordinates transmitted by the control center via radio. The control center then automatically sends a command to the second train to switch back to train mode. Unique identification data transmitted along with the switch command enables the first and second trains to establish local radio communication for information exchange. The control center then switches the second train from train mode to priority operation mode, in which it operates at its maximum permitted speed. Furthermore, the second train's onboard control equipment operates in a continuous target braking curve calculation mode, targeting the first train's rear end position coordinates to prevent collisions. This method only addresses train departure scheduling. It cannot address platform scheduling issues when trains enter and exit multiple stations, nor can it dynamically adjust the order of trains entering and exiting stations. Furthermore, the introduction of wireless communication and automated control systems increases overall system complexity. A failure in the wireless communication system could disrupt information exchange between two trains, leading to a collision and compromising safe operation.

[0004] A Chinese patent document with publication number CN116859849A discloses a method for "an AGVS virtual-reality fusion intelligent management and control system based on digital twins." The method includes an AGVS physical system, an AGVS virtual simulation system, a DDS twin data center, and an AGVS intelligent management and control system. The method utilizes digital twin technology to link dynamic path planning and multi-resource scheduling solutions based on AGVS discrete event simulation and multi-agent simulation. By mapping the AGVS physical system into the AGVS virtual simulation system, the simulation is combined with the actual AGVS system to achieve dynamic real-time simulation. Dynamic real-time simulation is used to continuously predict the next situation. For possible anomalies such as conflicts, various different resource collaborative scheduling methods are simulated and tried, thereby providing an optimized solution for the AGVS physical system, thereby reducing AGV conflicts and deadlocks within the system and timely optimizing the response to disturbances in the system. This enables intelligent analysis, prediction, and decision-making of the AGVS system operation process based on digital twins. This method does not provide a specific entry and exit scheduling plan for railway trains entering and leaving the station. Moreover, since it integrates multiple levels and components and involves the fusion of multiple complex technologies and complex computational analysis, it leads to complexity in implementation and maintenance, increasing initial investment and subsequent maintenance costs. Summary of the Invention

[0005] The purpose of the present invention is to address the deficiencies of the above-mentioned existing technologies and propose a partial binary tree fair train dispatching system and method based on supervisory control theory to sequentially dispatch trains entering and leaving multi-platform stations, avoid train collisions caused by failures in the wireless communication system, and reduce the complexity of the dispatching system and the construction and maintenance costs.

[0006] To achieve the above objectives, the technical idea of ​​the present invention is: to design a train entry and exit scheduling system through discrete event system supervisory control theory to realize the sequential scheduling of trains entering and exiting multi-platform stations; to reduce the system complexity and construction and maintenance costs by using the station's existing railway signal machines, switch switches, track sensors and other equipment for scheduling.

[0007] According to the above ideas, the present invention is based on the partial binary tree fair train scheduling system of supervisory control theory, including:

[0008] The station entry switch module is used to simulate the train entering the station;

[0009] Outbound turnout switch module, used to simulate the train outbound process;

[0010] Platform capacity specification module, used to constrain platform capacity;

[0011] The entry crossover capacity specification module is used to constrain the entry crossover capacity, that is, to constrain the capacity of the connecting track between two entry switches;

[0012] The outbound crossover capacity specification module is used to constrain the outbound crossover capacity, that is, to constrain the capacity of the connecting track between two outbound turnouts;

[0013] The station entry fair scheduling specification module is used to ensure that the number of trains entering each platform is in a relatively balanced state;

[0014] The outbound fair scheduling specification module is used to ensure that the number of trains leaving each platform is in a relatively balanced state;

[0015] The scheduling priority specification module is used to ensure that the platform priority decreases as the platform number increases.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] Firstly, the present invention uses the turnout switches for entering and exiting the station to simulate the process of trains entering and exiting the station, and can be combined with the existing sensor equipment and railway signal lights at the station to complete the simulation of the station's operating status;

[0018] Secondly, the present invention realizes the scheduling of trains entering and leaving the station through the turnout switch, without distinguishing the trains entering and leaving the station, thereby reducing the complexity and computational load of the scheduling of trains entering and leaving the station.

[0019] Thirdly, the present invention can realize platform capacity constraint and crossover capacity constraint by constructing platform capacity specification and crossover capacity specification;

[0020] Fourthly, the present invention can achieve full utilization of each platform by establishing fair scheduling specifications for trains entering and leaving the station;

[0021] Fifth, the present invention can realize dynamic adjustment of the order of train entry and exit by constructing a train entry and exit scheduling priority specification;

[0022] Sixth, the present invention performs platform scheduling based on the real-time status of the station switch rather than on time. The scheduling path it provides can further verify the correctness of the scheduling path based on the train schedule, thereby improving the safety of the railway system. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is an application background diagram of the present invention;

[0024] Figure 2 This is a simplified diagram of the station structure to which the present invention is applied;

[0025] Figure 3 This is a structural diagram of a first example of a station entrance and exit to which the present invention is applied;

[0026] Figure 4 This is a second example structural diagram of a station entrance and exit to which the present invention is applied;

[0027] Figure 5 This is a station entrance turnout control tree diagram applied by the present invention;

[0028] Figure 6 is a system diagram of the present invention;

[0029] Figure 7 It is a DES model diagram of the turnout switch in the present invention;

[0030] Figure 8 It is the DES model diagram of the platform capacity specification in the present invention;

[0031] Figure 9 This is a DES model diagram of the crossover capacity specification in the present invention;

[0032] Figure 10 This is the DES model diagram of the fair scheduling specification in the present invention;

[0033] Figure 11 It is the scheduling priority specification DES model diagram in the present invention;

[0034] Figure 12 This is a flowchart of the scheduling system implementation in the present invention. DETAILED DESCRIPTION

[0035] The following describes the embodiments of the present invention in detail with reference to the accompanying drawings. The first, second, third, fourth, fifth, sixth, seventh and eighth events in the description are only used to distinguish events of different contents, and are not a necessary order of events.

[0036] Reference Figure 1 ,The implementation background of this example is that there is a one-way single-track railway in a complex ,railway network. There are stations with multiple platforms on the line. Each ,train runs on a one-way single-track line.

[0037] like Figure 2 As shown, each station on a single-line one-way line includes an entrance I, an exit O, and platforms P1, P2, ..., P n There are two instance structures for station entrance I and exit O respectively. The first structure is as follows Figure 3 , the second structure is as follows Figure 4 .

[0038] Reference Figure 3 , the entrance structure I1 of this example station is as follows Figure 3 As shown in a, the outlet structure O1 is as follows Figure 3 As shown in b, the entrance structure I1 and the exit structure O1 are symmetrical about the platform. The entrance structure I1 consists of n-1 entry turnout switches. 2(n-1) entry sensors n-2 entry crossovers and n entry tracks Composition; trains can enter the station through the switch From the station track Switch to pit track The station entry sensor is used to collect the train's location information; the train enters the station track You will then enter Platform P i The exit structure O1 consists of n-1 outgoing turnout switches. 2(n-1) outbound sensors n-2 outbound crossovers and n outbound tracks Composition; trains can pass through the outbound turnout switch From the outbound track Switch to outbound track Outbound sensor Used to collect train location information; when the train leaves the platform P i Then it will enter the exit track i∈{1, 2, ..., n-1}, where n is the total number of stations.

[0039] Reference Figure 4 The entrance structure I2 of this example station is as follows Figure 4 As shown in a, the outlet structure O2 is as follows Figure 4 As shown in b, the entrance structure I2 and the exit structure O2 are symmetrical about the platform. The entrance structure I2 consists of n-1 entry turnout switches. 2(n-1) entry sensors n-2 track sections between entry switches and n entry tracks Composition; trains can enter the station through the switch From the station track Switch to pit track Entry sensor Used to collect train location information; train enters the station track You will then enter Platform P i The exit structure O2 consists of n-1 exit switch 2(n-1) outbound sensors n-2 outbound turnout track sections and n outbound tracks The train can pass the exit switch From the outbound track Switch to outbound track

[0040] To verify that the first instance and the second instance have structural similarities, it is necessary to extract the turnout switches of the first instance and the second instance. and Platform P i , and use this to build a turnout control tree model, the results are as follows Figure 5 As shown, where:

[0041] Figure 5 a is the switch control tree model extracted from the entrance structure of the first example. The model retains the topological structure of the entrance structure of the first example. is a branch node, platform P i It is a leaf node.

[0042] Figure 5 b is the switch control tree model extracted from the entrance structure of the second example. This model retains the topological structure of the entrance structure of the second example. Also a branch node, platform P i Also a leaf node.

[0043] from Figure 5 a and Figure 5As can be seen from b, the inlet structures of both the first and second instances are topological structures of a partially ordered binary tree. Since the inlet and outlet structures of the first and second instances are symmetrical about the platform axis, the outlet structures are also topological structures of a partially ordered binary tree.

[0044] This example uses Figure 5 The obtained binary tree topology of the entrance and exit of the two instances is used as a theoretical basis to design a fair train scheduling system.

[0045] Reference Figure 6 The dispatching system designed in this example includes: station turnout switch module Outbound turnout switch module Platform Capacity Specification Module Station entry crossover capacity specification module Outbound crossover capacity specification module Fair dispatch specification module for entering the station Outbound fair scheduling specification module and scheduling priority specification module SP i .in:

[0046] The station entry turnout switch module like Figure 7 As shown in a, it includes the state y0 of entering the station, the state y1 of connecting the left track of entering the station and the state y2 of connecting the right track of entering the station. When the left track needs to be connected, the first event Occurs, the station turnout switch transitions from state y0 to state y1; the train passes the turnout switch Trigger the left track sensor Second incident Occurrence, station turnout switch Reset from state y1 to state y0; when the entry switch When the right track needs to be connected, the third event Occurs, the station turnout switch transitions from state y0 to state y2; the train passes the turnout switch Trigger the right track sensor Fourth Incident Occurrence, station turnout switch It will also be reset from state y2 to state y0. For a station with n platforms, n-1 entry switch modules are required to simulate the train entry process.

[0047] The outbound turnout switch module like Figure 7 b; it includes the exit four open state w0, the exit left track connected state w1 and the exit right track connected state w2. When connecting to the left track, the fifth event Occurs, the outbound turnout switch transitions from state w0 to state w1; the train passes the turnout switch Trigger the left track sensor The Sixth Incident Occurrence, outbound turnout switch Reset from state w1 to state w0; when the outbound turnout switch When connecting to the right track, the seventh event Occurrence, outbound turnout switch Transition from state w0 to state w2; the train passes the switch Trigger the left track sensor The Eighth Incident Occurrence, outbound turnout switch It is also reset from state w2 to state w0; for a station with n platforms, n-1 exit turnout switch modules are required to simulate the train exit process.

[0048] Use the sync command in the TCT software to combine all entry and exit turnout switches into a DES model that simulates the complete entry and exit behavior of the train.

[0049] The platform capacity specification module like Figure 8 As shown, it includes the platform without train state a0 and the platform with train state a1. When the second event or the fourth event When this happens, the switch connects the left track or the right track, and a train will pass through the connected track and enter the platform P. i Module From state a0 to state a1, when the sixth event or the eighth incident Occurs, the train parked at the station leaves the platform P i , module Reset from state a1 to state a0. For a station with n platforms, n platform capacity specification modules are required to constrain the train capacity of the platform to 1 to prevent overflow and underflow of the platform capacity;

[0050] The entry crossover capacity specification module like Figure 9 As shown in a, it includes the state b0 of no train on the crossing line and the state b1 of train on the crossing line. When the fourth event of the i-th crossing line When the switch connects the right track, a train will enter the station crossing line. From state b0 to state b1, when the second event of the i+1th entry switch or the fourth event If the switch connects the left track or the right track, the train in the station crossing line will leave the station crossing line. Reset from state b1 to state b0. For a station with n platforms, n-2 entry crossover capacity specification modules are required to constrain the capacity of the entry crossover to 1. That is, constrain the capacity of the connecting track between the two entry switch switches to 1 to prevent overflow or underflow of the entry crossover capacity.

[0051] The outbound crossover capacity specification module like Figure 9 As shown in b, it includes the outbound crossover state c0 with no train and the outbound crossover state c1 with a train. When the second event of the i+1th outbound turnout switch or the fourth event If the switch connects the left track or the right track, a train will enter the outbound crossing line. From state c0 to state c1, when the eighth event of the i-th outbound switch When this happens, the switch connects the right track, which will cause the train in the outbound crossover to leave the outbound crossover. Reset from state c1 to state c0. For a station with n platforms, n-2 outbound crossover capacity specification modules are required to constrain the capacity of the outbound crossover to 1. That is, constrain the capacity of the connecting track between the two outbound turnout switches to 1 to prevent overflow or underflow of the outbound crossover capacity.

[0052] The fair dispatch specification module for entering the station like Figure 10 As shown in a, it includes the fair dispatching states d0, d1, ..., d n-i and the first event With the third event The purpose of this specification is to set the first event of the i-th entry switch in a station with n platforms The number of occurrences of the third event The number of occurrences meets Since a switch connects tracks, trains enter the connected track. Therefore, the number of times the first and third events occur can be used to represent the number of trains passing through the left and right tracks of the station switch. For a station with n platforms, n-1 station crossing capacity specification modules are required to ensure a relatively balanced number of trains entering each platform, improve platform resource utilization, reduce passenger waiting time, and ensure relatively consistent wear of the platform tracks, facilitating subsequent track maintenance.

[0053] The outbound fair scheduling specification module like Figure 10 As shown in b, it includes outbound fair scheduling states e0, e1, ..., e n-i and the fifth event and the Seventh Incident The purpose of this specification is to set the fifth event of the i-th outbound switch in a station with n platforms. The number of occurrences of the seventh event The number of occurrences meets Since a switch connects tracks, trains enter the connected track. Therefore, the number of times the first and third events occur can be used to represent the number of trains passing through the left and right tracks of the exit switch. For a station with n platforms, n-1 exit crossover capacity specification modules are required to ensure a relatively balanced number of trains departing each platform, improve platform resource utilization, reduce passenger waiting time, and ensure relatively consistent wear of the platform tracks, facilitating subsequent track maintenance.

[0054] Scheduling priority specification module SP i ,like Figure 11 As shown, it includes the dispatch priority state f0, the dispatch priority state f1, the sixth event of the i-th outbound turnout switch and the fourth event of the i-th entry switch This specification makes the sixth event of the i-th outbound turnout switch The occurrence of the fourth event of the i-th entry switch takes precedence over This ensures that the platform priority decreases as the platform number increases, further ensuring the safety of trains entering and leaving the station.

[0055] Use the sync command in the TCT software to synthesize all the canonical modules into a global canonical DES model.

[0056] Using the supcon command in the TCT software, a DES model simulating the complete train entry and exit behavior and a global standard DES model are input, outputting a dispatching system that meets all standard module requirements. The dispatching system then generates a dispatching path for train entry and exit, along with a list of prohibited events for each station state. This path is achieved by prohibiting the occurrence of events in the list, ensuring that only legal events occur under different train entry and exit states. This ensures that turnout switches connect tracks according to standard requirements, ultimately ensuring that trains enter and exit the station along the path specified by the dispatching system.

[0057] Reference Figure 12 In this example, the method for train dispatching using the above system includes the following steps:

[0058] Step 1. Get the array of prohibited events and system status variables.

[0059] The prohibited event list in each state obtained from the above system is filled into the corresponding prohibited event array to ensure that the events occurring in the system in different states are legal events, so as to realize the connection of the switch switch to the set track in different states of train entering and leaving the station;

[0060] According to different situations of the prohibited event lists in different states of the system, the current system state is obtained from the above system and filled into the system state variable to determine the prohibited event list corresponding to the state.

[0061] Step 2. Event judgment and control.

[0062] 2.1) Determine whether event E is about to occur in the current state of the scheduling system:

[0063] If no event E is about to occur, the process ends;

[0064] If yes, go to step 2.2);

[0065] 2.2) Determine whether event E exists in the prohibited event array under the current system state:

[0066] If it exists, then prohibit the execution of event E to prevent the switch from connecting to the wrong track, which would cause the train to enter the track and cause an accident; end the process.

[0067] If it does not exist, then execute event E, connect the switch to the set track, and the train will run on the path set by the dispatching system; and update the dispatching system status and return to step 2.1).

[0068] The above description is only a specific example of the present invention and does not constitute any limitation to the present invention. Obviously, for professionals in this field, after understanding the content and principles of the present invention, it is possible to make various modifications and changes in form and details without departing from the principles and structure of the present invention. However, these modifications and changes based on the ideas of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A partial binary tree fair train dispatching system based on supervisory control theory, characterized in that: include The station entry switch module is used to simulate the train entry process; The outbound turnout switch module is used to simulate the train outbound process; Platform capacity specification module, used to constrain platform capacity; The entry crossover capacity specification module is used to constrain the entry crossover capacity, that is, to constrain the capacity of the connecting track between two entry switches; The outbound crossover capacity specification module is used to constrain the outbound crossover capacity, that is, to constrain the capacity of the connecting track between two outbound turnouts; The station entry fair scheduling specification module is used to ensure that the number of trains entering each platform is in a relatively balanced state; The outbound fair scheduling specification module is used to ensure that the number of trains leaving each platform is in a relatively balanced state; The scheduling priority specification module is used to ensure that the platform priority decreases as the platform number increases.

2. The system according to claim 1, wherein: The station turnout switch module simulates a train The pit stop process is implemented as follows: Extract the entry four-open state y0, the entry left track connected state y1 and the entry right track connected state y2 of the i-th entry turnout switch; According to the different states of the i-th entry turnout switch, the following events of the i-th entry turnout switch are defined: The process of the station turnout switch transitioning from state y0 to state y1 is defined as the first event The process of resetting the entry turnout switch from state y1 to state y0 is defined as the second event The process of the station turnout switch transitioning from state y0 to state y2 is defined as the third event The process of resetting the entry switch from state y2 to state y0 is defined as the fourth event 3. The system according to claim 1, wherein: The outbound turnout switch module simulates a train The outbound process is implemented as follows: Extract the entry four-open state w0, the exit left track connected state w1, and the exit right track connected state w2 of the i-th exit turnout switch; According to the extraction of different states of the i-th outbound turnout switch, the following events of the i-th outbound turnout switch are defined: The process of the outbound turnout switch transitioning from state w0 to state w1 is defined as the fifth event The process of resetting the outbound turnout switch from state w1 to state w0 is defined as the sixth event The process of the outbound turnout switch transitioning from state w0 to state w2 is defined as the seventh event The process of resetting the outbound turnout switch from state w2 to state w0 is defined as the eighth event 4. The system according to any one of claims 1 to 3, characterized in that: The platform capacity specification module The capacity of the platform is constrained by the second event or the fourth event Only one train is allowed to enter the platform; pass the sixth event or the eighth incident Allow trains parked on the platform to leave the platform, thereby achieving platform capacity constraints and avoiding platform capacity overflow and underflow.

5. The system according to any one of claims 1 and 2, characterized in that The capacity specification of the station crossover The module constrains the entry crossover capacity, which is the fourth event of the i-th entry switch. Only one train is allowed to enter the station crossing; the second event of passing the i+1th station switch and the fourth event Allow trains parked on the entry crossover to move out of the entry crossover, thereby realizing the capacity constraint of the entry crossover and avoiding overflow and underflow of the entry crossover capacity.

6. The system according to any one of claims 1 and 3, characterized in that The outbound crossover capacity specification The module constrains the outbound crossover capacity, which is the second event of the i+1th outbound turnout switch. and the fourth event Only one train is allowed to enter the outbound crossover; the eighth event of passing the i-th outbound switch Allow trains parked on the outbound crossover to leave the outbound crossover, thereby realizing the outbound crossover capacity constraint and avoiding overflow and underflow of the outbound crossover capacity.

7. The system according to any one of claims 1-2, characterized in that: The fair scheduling module for entering the station ensures that the number of trains entering each platform is in a relatively balanced state. It sets the first event of the i-th entry switch in a station with n platforms. The number of occurrences of the third event The number of occurrences meets quantitative relationship.

8. The system according to any one of claims 1 to 3, characterized in that: The fair dispatching module ensures that the number of trains leaving each platform is in a relatively balanced state. It sets the first event of the i-th outgoing turnout switch in a station with n platforms. The number of occurrences and the third event The number of occurrences meets quantitative relationship.

9. The system according to any one of claims 1 to 3, characterized in that: The scheduling priority specification module ensures that the platform priority decreases as the platform number increases, by setting the sixth event of the i-th outbound turnout switch The fourth event that takes precedence over the i-th entry switch to achieve.

10. A method for scheduling train entry and exit using the system of claim 1, characterized in that: The steps include: (1) Obtain the prohibited event list and status from the scheduling system and fill them into the prohibited event array and system status variables; (2) Determine whether event E is about to occur in the current state of the scheduling system: If no event E is about to occur, the process ends; If yes, go to step (3); (3) Determine whether event E exists in the prohibited event array under the current system state: If it exists, then prohibit event E from executing and end the process; If it does not exist, go to step (4); (4) Execute event E, that is, connect the switch to the set track, so that the train runs normally along the path set by the dispatching system, and update the dispatching system status, and return to step (2).

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