JP2024099315A - Train Control System - Google Patents

Abstract

To provide a train control system that can reliably transmit information between the ground and onboard trains and ensure safe train operation by means of a stable radio communication environment that can handle various types of trains.SOLUTION: A train control system 1 wirelessly transmits stop point information on security from a ground controller 2 to an onboard controller 4 of each train T via a plurality of radio facilities 3 along the line and an onboard radio facility 5 of each train T. In this train control system 1, the ground controller 2 determines a communication range of each radio facility 3 on the line on the basis of the train's position on a track R, and wirelessly transmits the communication limit point information to the onboard controller 4 when the train T is outside the communication range of all the radio facilities 3 along the line ahead of it, and the onboard controller 4 performs train control on the basis of the received stop point information and communication limit point information.SELECTED DRAWING: Figure 2

Description

The present invention relates to a train control system that controls trains by exchanging information between ground and on-board stations via wireless communication.

For example, a wireless train control system called CBTC (Communication Based Train Control) realizes safe train operation (moving block operation) by exchanging information wirelessly between on-board control devices installed on trains and ground control devices installed on the ground via ground-side radio stations (wayside radio equipment) and on-board radio stations (on-board radio equipment). In such wireless train control systems, low-power radio stations that do not require a license as stipulated in the Radio Law are widely used. However, because low-power radio stations have a narrow communication area, if there are obstacles such as other trains between the ground-side radio stations, the wireless communication may become unstable, affecting train control. It is known that the communication range of wayside radio equipment is narrowed, especially in tunnels and underground tracks, due to radio wave shielding by the train body, etc.

For example, in the wireless communication network system disclosed in Patent Document 1 as a conventional technology for stabilizing wireless communication in the wireless train control system described above, two train radios (on-board radio stations) are placed at the front and rear of a train, and each train radio is connected by a wired cable so that they can communicate with each other. Then, in cases where the presence of a train between wayside radios (ground-side radio stations) that can wirelessly communicate with each other disrupts wireless communication between the wayside radios, the two train radios installed on the train are used to relay information between the wayside radios. This increases the reliability of the wireless communication network.

JP 2013-42344 A

However, in the case of the above-mentioned conventional technology, when train control targets include freight trains in which a locomotive pulls vehicles such as freight cars that do not have radio stations, or rescue trains that pull broken-down vehicles, the freight trains and rescue trains have on-board radio stations only at either the front or rear. Therefore, if a freight train or rescue train is between ground-side radio stations and wireless communication between the respective radio stations is obstructed, it becomes difficult for the freight train or rescue train to relay information transmission between the above-mentioned ground-side radio stations. Furthermore, even if a train has on-board radio stations at both the front and rear, if one of the radio stations breaks down or if a problem occurs in the wired cable connecting the front and rear radio stations, it will no longer be possible to relay information transmission between the above-mentioned ground-side radio stations. For this reason, the conventional technology has room for improvement in terms of realizing a stable wireless communication environment that can be used with various trains.

The present invention was made with the above points in mind, and aims to provide a train control system that can reliably transmit information between ground and on-board stations in a stable wireless communication environment that is compatible with various types of trains, ensuring safe train operation.

To achieve the above object, one aspect of the present invention provides a train control system that wirelessly transmits safety stop point information from ground equipment to the on-board equipment of the train via multiple radio stations installed along the track. In this train control system, the ground equipment determines the communication range of each radio station based on the train's position on the track, and wirelessly transmits communication limit point information, where the train is outside the communication range of all radio stations ahead, to the on-board equipment, which then controls the train based on the received stop point information and communication limit point information.

As described above, the train control system of the present invention enables train control that prevents the train being controlled from entering a section where wireless communication becomes unstable due to the presence of other trains on the line, so a stable wireless communication environment between the ground and on-board can be maintained. Such a train control system does not require wireless equipment to be installed at both the front and rear of the train, so it can also be used with freight trains, rescue trains, and the like. Therefore, a stable wireless communication environment that can be used with various trains can ensure the reliable transmission of information between the ground and on-board, ensuring safe train operation.

1 is a schematic configuration diagram showing an embodiment of a train control system according to the present invention; FIG. 2 is a block diagram showing a specific configuration example of the train control system according to the above embodiment. FIG. 1 is a conceptual diagram for explaining a basic model of received power in wireless communication between ground and on-board. FIG. 11 is a diagram showing an example of communication range data in the embodiment. FIG. 2 is a conceptual diagram for explaining communication ranges of a plurality of wayside radio equipment in the embodiment. 4 is a conceptual diagram for explaining an actual communication range determined by a communication range determination unit in the embodiment. FIG. FIG. 11 is a conceptual diagram for explaining a communication limit point in the embodiment. FIG. 2 is a diagram showing an example of a speed inspection pattern created in the above embodiment. A block diagram showing an example of the functional configuration of a speed verification unit, a brake control unit, and a brake device in the above embodiment. FIG. 4 is a conceptual diagram showing a basic processing cycle of train control in the embodiment. 5 is a flowchart showing a specific process flow executed by a ground control device in the embodiment. 4 is a flowchart showing a specific process flow executed by the on-board control device in the embodiment. FIG. 11 is a diagram showing an example of a specific situation regarding speed inspection and brake control in the above embodiment. FIG. 14 is a diagram for explaining speed checking and brake control performed in the situation of FIG. 13. FIG. 13 is a diagram for explaining a modification related to the above embodiment.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram showing an embodiment of a train control system according to the present invention.
In FIG. 1, the train control system 1 of this embodiment is configured to include a ground control device 2 installed on the ground, a plurality of wayside radio equipment 3 (3A, 3B, 3C, ...) installed along a track R along which a train T runs, and an on-board control device 4 and on-board radio equipment 5 mounted on each train T on the track R.

The ground control device 2 and the multiple wayside radio equipment 3 are connected so as to enable two-way communication by wire or wirelessly. The ground control device 2 has a ground database (not shown). The ground database includes wayside information of the track R (installation positions of the wayside radio equipment 3 and signals S, the positions of the terminal points on the track R, and the locations of tunnels and underground track sections, etc.), vehicle information of each train T running on the track R (type of train, length of train, identifier, etc.), information on the multiple ground coils installed along the track R (identifiers (ID) and installation positions of each ground coil), etc.

In the train control system 1 of this embodiment, the ground control device 2 and the on-board control device 4 of each train T exchange various information by wireless communication via each wayside radio equipment 3 and the on-board radio equipment 5 of each train T, and each train T is controlled based on the exchanged information. Such a train control system 1 is suitable as a system for performing train control using the CBTC method. In this embodiment, the ground control device 2 corresponds to the "ground device" of the present invention, the multiple wayside radio equipment 3 corresponds to the "multiple radio stations" of the present invention, and the on-board control device 4 and on-board radio equipment 5 correspond to the "on-board device" of the present invention.

Each component of the train control system 1 according to this embodiment will be described in detail below.
FIG. 2 is a block diagram showing a specific configuration example of the train control system 1 according to this embodiment.
In Figure 2, the ground control device 2 has, for example, a train position update unit 20, a stop point determination unit 21, a stop point distance calculation unit 22, a communication range determination unit 23, a communication limit point distance calculation unit 24, a data memory unit 25, a data correction unit 26, a control command creation unit 27, and a control command transmission unit 28.

The train position update unit 20 is provided with information indicating the track position of each train T received by the radio transmission/reception unit 30 of each wayside radio equipment 3. The radio transmission/reception unit 30 of each wayside radio equipment 3 is configured to transmit and receive radio signals between the on-board radio equipment 5 of each train T via the ground antenna 31. The train position update unit 20 aggregates the information indicating the track position of each train T, grasps the positions of all trains T on the track R, and creates and stores train position information that compiles the results and maps them on a route map. The stored train position information is updated each time new information is provided from each wayside radio equipment 3. The train position information includes, for example, information indicating the head (front end) position of each train T on the track R, which is stored in association with the identifier of each train T. The train position information updated by the train position update unit 20 is transmitted to the stop point determination unit 21 and the communication range determination unit 23, respectively.

The stop point determination unit 21 determines a safety stop point Ps corresponding to each train T on the track R based on the train position information transmitted from the train position update unit 20, the current indication information of the signal S installed along the track R, and the position information of the end point of the track R. Specifically, for each train T on the track R, the stop point determination unit 21 selects the point closest to the train to be controlled from among the rear end position of the other train (preceding train) ahead of the train to be controlled in the running direction, the position of the signal S with a stop indication ahead of the train to be controlled, and the position of the end point of the track R on which the train to be controlled runs, and determines the selected point as the safety stop point Ps of the train to be controlled.

Regarding the position of the rear end of the preceding train, first, the preceding train that exists ahead of the train on the track R on which the train itself runs is identified using the train position information from the train position update unit 20. Then, the train length of the preceding train is obtained by referring to the vehicle information of each train T in the ground database described above, and the position of the rear end is calculated according to the head position and train length of the preceding train. Regarding the position of the stop signal S, first, the stop signal S ahead of the train itself is identified using the indication information of each signal S given from time to time to the ground control device 2 by a signal control device (not shown) that controls the indication state of each signal S installed along the track R. Then, the installation position of the stop signal S is determined using the trackside information in the ground database. Furthermore, regarding the position of the terminal point of the track R, the position of the front terminal point on the track R on which the train itself runs is determined using the trackside information in the ground database.

Among the above-mentioned positions of the rear end of the preceding train, the position of the stop signal, and the position of the end point of the track R, the point closest to the train itself is the safety stop point Ps, which the train itself must not enter in order to ensure the safety of train operation. In other words, the safety stop point Ps represents the running limit point before which the train must be stopped. The safety stop point Ps of each train T determined by the stop point determination unit 21 is transmitted to the stop point distance calculation unit 22 together with the train position information from the train position update unit 20.

The stopping point distance calculation unit 22 calculates the stopping point distance from the leading position of each train T to the safety stopping point Ps using the safety stopping point Ps and train position information of each train T transmitted from the stopping point determination unit 21. Then, information indicating the stopping point distance of each train T calculated by the stopping point distance calculation unit 22 is transmitted from the stopping point distance calculation unit 22 to the control command creation unit 27.

The communication range determination unit 23 determines the actual communication range corresponding to each wayside radio equipment 3 based on the train position information updated by the train position update unit 20 described above and the communication range data of each wayside radio equipment 3 stored in the data storage unit 25, while taking into consideration the type of train T and its current position on the track R, as well as the operating status of each wayside radio equipment 3. The communication range data of each wayside radio equipment 3 is data indicating the communication range based on the received power in wireless communication between each wayside radio equipment 3 and each train T (between the ground and on board).

Figure 3 is a conceptual diagram for explaining a basic model of the received power in ground-to-train wireless communication. The curve PR shown in Figure 3 shows the change in the received power when the horizontal axis is the position of the on-board wireless equipment 5 of the train T traveling on the track R and the vertical axis is the power (dBm) when the on-board wireless equipment 5 receives a wireless signal transmitted from the ground antenna 31 of the wayside wireless equipment 3. In this embodiment, the on-board wireless equipment 5 has a wireless transceiver 50 and an on-board antenna 51 (Figure 2), and the on-board antenna 51 is installed at the front of the train T. In this model, as the train T approaches the ground antenna 31 of the wayside wireless equipment 3, the received power PR at the on-board wireless equipment 5 gradually increases, and when the on-board antenna 51 reaches the position of the ground antenna 31, the received power PR is maximized, and as the on-board antenna 51 moves away from the ground antenna 31, the received power PR rapidly decreases.

By setting a lower limit value PR (hereinafter referred to as "stable communication limit value") PR L of the receiving power PR at which stable wireless communication can be performed between the wayside and the on-board in response to such changes in the receiving _power PR at the on-board radio equipment 5, it is possible to define a communication range Ac that spreads forward and backward along the track R with the installation position of the wayside radio equipment 3 (ground antenna 31) as the reference point. Note that in the model of FIG. 3, since two-way communication is performed between the wayside and the on-board radio equipment, it is assumed that the wayside radio equipment 3 and the on-board radio equipment 5 have equivalent transmission and reception performance. If there is a difference in the transmission and reception performance of the wayside radio equipment 3 and the on-board radio equipment 5, it is necessary to narrow the communication range Ac by correcting it to increase the stable communication limit value PR _L to match the side with poorer performance.

The communication range Ac of the wayside radio equipment 3 defined according to the basic model as described above varies depending on the type and running direction (upward/downward) of the train T with which it communicates. For this reason, the communication range Ac corresponding to the type and running direction of the train T is calculated in advance for each wayside radio equipment 3, and communication range data indicating each communication range Ac is stored in the data storage unit 25.

FIG. 4 is a diagram showing an example of communication range data stored in the data storage unit 25. As shown in FIG.
As shown in the upper part of Figure 4, the data storage unit 25 stores a table (communication range data) for each wayside radio equipment 3A, 3B, 3C..., for each type of train X, Y, Z with which communication is to take place, which includes a pair of data D1, D2 indicating the communication range Ac of a train T traveling in the downward direction and a pair of data D3, D4 indicating the communication range Ac' of a train T' traveling in the upward direction.

In this table, train types X, Y, and Z represent differences in train type (passenger train, freight train, etc.), length of train set, and type of on-board radio equipment 5. Data D1 corresponding to down train T, as shown in the lower part of FIG. 4, represents the distance (D1 = |P1-P0|) from reference point P0, which is the installation position of wayside radio equipment 3 (ground antenna 31), to first limit point P1. First limit point P1 is the point at which communication is limited on the upbound side in communication range Ac of down train T. Data D2 corresponding to down train T represents the distance (D2 = |P2-P0|) from reference point P0 to second limit point P2. Second limit point P2 is the point at which communication is limited on the downbound side in communication range Ac of down train T. Like the data D1 and D2 corresponding to the down train T as described above, the data D3 corresponding to the up train T' represents the distance from the reference point P0 to the third limit point P3 (D3 = |P3 - P0|). The third limit point P3 is the point where communication is limited on the up direction side in the communication range Ac' of the up train T'. The data D4 corresponding to the up train T' represents the distance from the reference point P0 to the fourth limit point P4 (D4 = |P4 - P0|). The fourth limit point P4 is the point where communication is limited on the down direction side in the communication range Ac' of the up train T'.

As described above, the communication range Ac of the down train T and the communication range Ac' of the up train T' at each wayside radio equipment 3A, 3B, 3C, etc., extend along each track R in the up and down directions, centered on the installation position (reference point P0) of the ground antenna 31, and the parts corresponding to data D2 and D3 overlap in both communication ranges Ac, Ac'.

Generally, wireless equipment can experience a decline in transmission/reception performance and an increase in communication error rate due to aging or changes in the surrounding environment. In this embodiment, each wayside wireless equipment 3 is a fixed station with a fixed installation location, and therefore has the property that the reception power and communication error rate in wireless communication between each wayside wireless equipment 3 are approximately constant. Taking advantage of this property, in this embodiment, the data correction unit 26 is configured to monitor and evaluate the change over time in at least one of the reception power and communication error rate in wireless communication between each wayside wireless equipment 3, and correct the data D1 to D4 in the table stored in the data storage unit 25 according to the evaluation result.

Specifically, information on the reception power and/or communication error rate obtained by mutual wireless communication between adjacent wayside radio equipment 3 is transmitted from each wayside radio equipment 3 to the data correction unit 26 at a required monitoring period. The data correction unit 26 calculates the rate of change over time of the reception power and/or communication error rate for each wayside radio equipment 3 to evaluate the reception status of each equipment. The data correction unit 26 then executes a correction process for the communication range data by multiplying the data D1 to D4 in the table stored in the data storage unit 25 by the above-mentioned change rate corresponding to each wayside radio equipment 3. Note that even if any of the multiple wayside radio equipment 3 fails, the data correction unit 26 can deal with the situation by correcting the communication range data of the failed wayside radio equipment in the same manner as above (changing the data D1 to D4 to 0 m).

In this embodiment, the communication range determination unit 23 uses the communication range data corrected by the data correction unit 26 at the required monitoring cycle as described above and the train position information from the train position update unit 20 to determine the actual communication range corresponding to each wayside radio equipment 3, taking into consideration the type of train T and its current position on the track R, as well as the operating status of each wayside radio equipment 3, etc.

Figure 5 is a conceptual diagram for explaining the communication ranges Ac, Ac' of multiple wayside radio equipment 3 in this embodiment. Figure 5 shows an example in which four wayside radio equipment 3A, 3B, 3C, 3D are installed along a tunnel or underground track section on track R. The layout of the wayside radio equipment 3A-3D is usually designed so that the on-board radio equipment 5 of the train on track R is simultaneously located within the communication range of two or more wayside radio equipment, allowing multiple redundant communication paths to be formed, in order to maintain stable communication between the ground control device 2 and the on-board control device 4 of the train T.

The upper part of FIG. 5 shows the communication range Ac of down trains and the communication range Ac' of up trains corresponding to each wayside radio equipment 3A-3D when there are no trains in the tunnel or underground track section. Note that FIG. 5 omits the illustration of the overlapping portion of the communication range Ac of down trains and the communication range Ac' of up trains for one wayside radio equipment. In the situation shown in the upper part of FIG. 5, the communication ranges Ac (Ac') of adjacent wayside radio equipment in the same direction overlap at any position in the tunnel or underground track section, making it possible to form two redundant communication paths. The communication range data stored in the data storage unit 25 corresponds to data showing the communication ranges Ac, Ac' of each wayside radio equipment 3A-3D as shown in the upper part of FIG. 5 for each type of train T, X-Z, with which communication is to take place.

Meanwhile, the lower part of Fig. 5 shows the communication range Ac of down trains and the communication range Ac' of up trains corresponding to each of the wayside radio equipment 3A-3D when a train T is between the wayside radio equipment 3B, 3C. In such a situation, the radio signals transmitted from each of the wayside radio equipment 3A-3D are blocked by the train T located between the wayside radio equipment 3B, 3C, narrowing the communication ranges Ac, Ac' of each of the wayside radio equipment 3A-3D (see the area surrounded by the dashed line in Fig. 5). Specifically, with regard to the communication range Ac' of up trains for each wayside radio equipment 3A, 3B, communication is not possible in the part that overlaps with the train T located between the wayside radio equipment 3B, 3C and in the part on the down direction side of the train T. In addition, for the communication range Ac of down trains at each wayside radio equipment 3C, 3C, communication is not possible in the area that overlaps with train T and in the area upstream of train T.

The communication ranges Ac, Ac' of each wayside radio equipment 3 installed along the track R as described above may change depending on the position of the train T on the track R, and such changes are particularly likely to occur in tunnels or underground track sections. For this reason, the communication range determination unit 23 in this embodiment uses the latest train position information to determine (update) the actual communication ranges Ac, Ac' of each wayside radio equipment 3 each time the train position update unit 20 updates the train position information.

Figure 6 is a conceptual diagram for explaining the actual communication range Ac determined by the communication range determination unit 23 in this embodiment. Figure 6 illustrates how the communication range Ac corresponding to each of the wayside radio equipment 3A-3D changes when another train T2 is present ahead of the down train T1, which is the communication partner of each wayside radio equipment 3A-3D in Figure 5 described above. Note that Figure 6 only illustrates the communication range Ac of the down train, and does not illustrate the communication range Ac' of the up train.

The upper part of FIG. 6 shows the communication ranges Ac corresponding to each of the wayside radio equipment 3A-3D in a situation where the down train T1 is located in front of the wayside radio equipment 3A and another train T2 is located at a position straddling the wayside radio equipment 3B. In this situation, the communication range determination unit 23 determines the communication range Ac of the wayside radio equipment 3A to be the range from a position near the wayside radio equipment 3A (ground antenna 31) (corresponding to the second limit point P2 in FIG. 4) to near the front of the train T1. On the other hand, with regard to the communication range Ac of the wayside radio equipment 3B, the radio signal transmitted from the wayside radio equipment 3B is blocked by the other train T2. For this reason, the communication range determination unit 23 determines that there is no communication range (communication is not possible) for the wayside radio equipment 3B. The communication range determination unit 23 also determines the communication range Ac of the wayside radio equipment 3C as the range from the vicinity of the wayside radio equipment 3C to the vicinity of the front of the other train T2, and determines the communication range Ac of the wayside radio equipment 3D as the range from the vicinity of the wayside radio equipment 3D to the vicinity of the front of the other train T2. In the situation shown in the upper part of Figure 6, the on-board radio equipment 5 of the train T1 is located only within the communication range Ac of the wayside radio equipment 3A, so that no redundant communication paths are formed and only one communication path can be formed.

The middle part of FIG. 6 shows the communication ranges Ac corresponding to each of the wayside radio equipment 3A to 3D in a situation where the down train T1 is located in front of the wayside radio equipment 3A and the other train T2 is located between the wayside radio equipment 3B and 3C. In this situation, compared to the situation shown in the upper part of FIG. 6, the radio signal transmitted from the wayside radio equipment 3B is not blocked by the other train T2, so the communication range determination unit 23 determines the range from the vicinity of the wayside radio equipment 3B to the vicinity of the front of the train T1 as the communication range Ac of the wayside radio equipment 3B. The communication ranges Ac of each of the wayside radio equipment 3A, 3C, and 3D other than the wayside radio equipment 3B are determined to be the same as those in the upper part of FIG. 6 described above. However, because the other train T2 has moved between the wayside radio equipment 3B and 3C, the communication ranges Ac of each of the wayside radio equipment 3C and 3D are narrower than those in the upper part of FIG. 6. In the situation shown in the middle of Figure 6, the on-board radio equipment 5 of train T1 is located within the communication range Ac of the two wayside radio equipment 3A and 3B, so it is possible to form two redundant communication paths.

The lower part of FIG. 6 shows the communication ranges Ac corresponding to each of the wayside radio equipment 3A to 3D in a situation where the down train T1 is located between the wayside radio equipment 3A and 3B, and another train T2 is located between the wayside radio equipment 3C and 3D. In this situation, the communication range determination unit 23 determines the communication range Ac of the wayside radio equipment 3A according to the communication range data stored in the data storage unit 25. In addition, the communication range determination unit 23 determines the communication range Ac of the wayside radio equipment 3B from the vicinity of the wayside radio equipment 3B to the vicinity of the front of the train T1, and determines the communication range Ac of the wayside radio equipment 3C from the vicinity of the wayside radio equipment 3C to the vicinity of the front of the train T1. Furthermore, the communication range determination unit 23 determines the communication range Ac of the wayside radio equipment 3D from the vicinity of the wayside radio equipment 3D to the vicinity of the front of the other train T2. In the situation shown in the lower part of Figure 6, the on-board radio equipment 5 of train T1 is located within the communication range Ac of the two wayside radio equipment 3B and 3C, so it is possible to form two redundant communication paths.

The communication range determination unit 23 determines the communication range Ac' of the upbound train, taking into account the on-track location of the upbound train, in the same way as in the case of the communication range Ac of the downbound train described above. The communication ranges Ac, Ac' corresponding to each wayside radio equipment 3 determined by the communication range determination unit 23 are then transmitted to the communication limit point distance calculation unit 24 together with the train position information from the train position update unit 20 (Figure 2).

The communication limit point distance calculation unit 24 sets a communication limit point Pc for each train on the track R at which the train to be controlled (the train itself) is outside the communication range of all wayside radio equipment 3 ahead, based on the communication ranges Ac, Ac' corresponding to each wayside radio equipment 3 transmitted from the communication range determination unit 23, and calculates the distance from the head position of the train itself to the communication limit point Pc (hereinafter referred to as the "communication limit point distance"). Note that in this embodiment, the communication range determination unit 23 and the communication limit point distance calculation unit 24 correspond to the "communication limit point determination unit" of the present invention.

Figure 7 is a conceptual diagram for explaining the communication limit point Pc set by the communication limit point distance calculation unit 24 in this embodiment. Note that in Figure 7, as in Figure 6 described above, only the communication range Ac of the down train is shown, and the communication range Ac' of the up train is omitted.

The upper part of Fig. 7 shows the communication limit point Pc of train T (own train) when the train T is located between wayside radio equipment 3A and 3B among four wayside radio equipment 3A to 3D installed along the track R. In such a situation, the communication limit point distance calculation unit 24 uses the communication ranges Ac of each wayside radio equipment 3A to 3D determined by the communication range determination unit 23 to set the communication limit point Pc as the boundary position where the on-board radio equipment 5 of train T first falls outside the communication ranges Ac of all wayside radio equipment 3B to 3D installed on the running direction (downward direction) of train T. In the example shown in the upper part of Fig. 7, the communication ranges Ac of each wayside radio equipment 3B to 3D installed in front of train T overlap and continue in order as they proceed in the downward direction. Therefore, the downstream limit point (corresponding to the second limit point P2 in FIG. 4) of the communication range Ac of the wayside radio equipment 3D that is farthest from the train T is set as the communication limit point Pc of the train T.

The middle part of Figure 7 shows the communication limit point Pc of train T when train T (the train itself) is located between wayside radio equipment 3A and 3B, and wayside radio equipment 3B has failed and communication is not possible. In this situation, even if wayside radio equipment 3B has failed, the on-board radio equipment 5 of train T is located within the communication range Ac of wayside radio equipment 3C beyond it, and is therefore able to communicate with the wayside radio equipment 3C. For this reason, the communication limit point distance calculation unit 24 sets the downstream limit point of the communication range Ac of wayside radio equipment 3D as the communication limit point Pc of train T, as in the case shown in the top part of Figure 7.

The lower part of Figure 7 shows the communication limit point Pc of train T1 in a situation where train T1 (the train itself) is located between wayside radio equipment 3A and 3B, and another train T2 (the preceding train) is located across wayside radio equipment 3D. In this situation, the radio signal transmitted from wayside radio equipment 3D is blocked by the other train T2, making communication impossible for wayside radio equipment 3D. For this reason, the communication limit point distance calculation unit 24 sets the communication limit point Pc of train T1 to the downstream limit point of the communication range Ac of wayside radio equipment 3C, which is one equipment before wayside radio equipment 3D.

When the communication limit point Pc of the train (own train) is set as described above, the communication limit point distance calculation unit 24 uses the train position information to calculate the communication limit point distance from the head position of the train to the communication limit point Pc. When the communication limit point distance calculation unit 24 calculates the communication limit point distance of each train T on the track R, information indicating the communication limit point distance of each train T (communication limit point information) is transmitted from the communication limit point distance calculation unit 24 to the control command creation unit 27 (Figure 2).

The control command creation unit 27 uses the information transmitted from the stop point distance calculation unit 22 and the communication limit point distance calculation unit 24 to create a control command for instructing each train T on the track R to be allowed to run. This control command includes the stop point distance and communication limit point distance associated with the identifier of each train T. The control command created by the control command creation unit 27 is transmitted to the control command transmission unit 28.

The control command transmission unit 28 generates a transmission signal by converting the control command from the control command creation unit 27 according to a predetermined communication protocol. The transmission signal generated by the control command transmission unit 28 is sent from the ground control device 2 to the wireless transmission/reception unit 30 of each wayside wireless equipment 3.

The radio transceiver 30 of each wayside radio equipment 3 receives a transmission signal (control command) from the ground control device 2 and transmits a radio signal including the control command from the ground antenna 31 to each train T on the track R. The on-board radio equipment 5 of each train T located within the communication range Ac, Ac' of each wayside radio equipment 3 receives the radio signal transmitted from the ground antenna 31 at the radio transceiver 50 via the on-board antenna 51 installed at the front of the train. The received signal of the radio transceiver 50 is sent from the on-board radio equipment 5 to the on-board control device 4.

As shown in FIG. 2 , the on-board control device 4 has a speed detection unit 40 , a train position detection unit 41 , a pattern creation unit 42 , a speed inspection unit 43 , and a brake control unit 44 .
The speed detection unit 40 detects (calculates) the speed and running distance of the train T based on an output signal of a speed generator (not shown) mounted on the train T. The speed and running distance of the train T detected (calculated) by the speed detection unit 40 are transmitted to the train position detection unit 41 and the speed verification unit 43, respectively.

The train position detection unit 41 calculates the on-track position of the train T (train location) based on the ground coil information received by an on-board coil (not shown) attached to the front bottom of the train T and the speed and travel distance of the train T transmitted from the speed detection unit 40, and updates the on-track position of the train T at a predetermined period C (e.g., 0.5 seconds). The ground coil information is information transmitted from each on-board coil (not shown) installed along the track R, and is received when the on-board coil passes above the ground coil.

To explain this with a specific example, when the on-board coil receives the ground coil information, the train position detection unit 41 acquires the identifier (ID) of the ground coil contained in the ground coil information. Then, based on the timing of receiving the ground coil information, the train position detection unit 41 calculates the relative position of the train T with respect to the ground coil using the travel distance transmitted from the speed detection unit 40, and detects the relative position information of the train T associated with the ground coil identifier as information indicating the on-line position of the train T. The train position detection unit 41 repeatedly executes such a detection process of the on-line position of the train T at a predetermined period C, and updates the on-line position of the train T. However, the method of detecting and updating the train position in the train position detection unit 41 is not limited to the above example.

The information indicating the current track position of train T updated by the train position detection unit 41 is transmitted to the speed verification unit 43 and also sent to the radio transmission/reception unit 50 of the on-board radio equipment 5. The radio transmission/reception unit 50 of the on-board radio equipment 5 receives the information indicating the current track position of train T from the train position detection unit 41, and transmits a radio signal including the information from the on-board antenna 51 to the wayside radio equipment 3.

The pattern creation unit 42 creates two types of speed check patterns (first speed check pattern V1, second speed check pattern V2) based on the control command from the ground control device 2 contained in the radio signal received by the radio transmission/reception unit 50 of the on-board radio equipment 5. The first speed check pattern V1 is a pattern that indicates a speed change for stopping the train T by the safety stopping point Ps instructed by the control command so that the train T can run safely. The second speed check pattern V2 is a pattern that indicates a speed change for stopping the train T by the communication limit point Pc instructed by the control command so that radio communication between the ground and the on-board is maintained.

FIG. 8 is a diagram showing an example of two types of speed inspection patterns created by the pattern creation unit 42 in this embodiment.
As shown in the upper part of Fig. 8, the first speed inspection pattern V1 created by the pattern creation unit 42 shows the change in the safety limit speed (solid line) and the change in the safety limit speed (dashed line) in the section from the location of the train T on the track (distance 0 m) to the safety stop point Ps that is a stop point distance away in the running direction. The change in the safety limit speed shown by the first speed inspection pattern V1 represents a deceleration pattern for stopping the train T before the safety stop point Ps by operating the service brake of the train T when the speed of the train T exceeds the safety limit speed. The change in the safety limit speed shown by the first speed inspection pattern V1 represents a deceleration pattern for stopping the train T at the safety stop point Ps by operating the emergency brake of the train T when the speed of the train T exceeds the safety limit speed. The safety limit speed shown by the first speed inspection pattern V1 is slightly higher than the safety limit speed at each distance (location of the train on the track) shown on the horizontal axis.

The second speed inspection pattern V2 created by the pattern creation unit 42 shows the change in the speed limit in the section from the location of the train T (distance 0 m) on the line to the communication limit point Pc, which is the communication limit point distance away in the running direction, as shown in the lower part of Figure 8. The change in the speed limit shown by the second speed inspection pattern V2 represents a deceleration pattern for activating the service brakes of the train T to stop the train T by the communication limit point Pc when the speed of the train T exceeds the speed limit. The deceleration curve (brake rate) represented by the change in the speed limit shown by the second speed inspection pattern V2 is basically set to be the same as the deceleration curve represented by the change in the safety speed limit shown by the first speed inspection pattern V1. The first speed inspection pattern V1 and the second speed inspection pattern V2 created by the pattern creation unit 42 as described above are transmitted to the speed inspection unit 43 (Figure 2).

The speed inspection unit 43 independently inspects the speed of the train T detected by the speed detection unit 40 against the first speed inspection pattern V1 (safety limit speed, safety speed limit) created by the pattern creation unit 42, and the speed of the train T detected by the speed detection unit 40 against the second speed inspection pattern V2 (speed limit) created by the pattern creation unit 42, and outputs a signal indicating each speed inspection result to the brake control unit 44. The brake control unit 44 generates a control signal for controlling the operation of the brake device 6 (emergency brake and regular brake) of the train T according to the speed inspection result in the speed inspection unit 43, and outputs the control signal to the brake device 6.

FIG. 9 is a block diagram showing an example of the functional configuration of the speed checking unit 43 and the brake control unit 44 of the on-board control device 4, and the brake device 6.
9, the speed check unit 43 of the on-board control device 4 independently performs a speed check against the safety limit speed indicated by the first speed check pattern V1, a speed check against the safety limit speed indicated by the first speed check pattern V1, and a speed check against the speed limit corresponding to the communication limit point Pc indicated by the second speed check pattern V2. The brake control unit 44 receives a signal indicating the result of the speed check against the safety limit speed in the speed check unit 43, and generates a control signal for activating the emergency brake 6A of the brake device 6 when the speed of the train T exceeds the safety limit speed. The brake control unit 44 also calculates a logical sum between the signal indicating the result of the speed check against the safety limit speed in the speed check unit 43 and the signal indicating the result of the speed check against the speed limit corresponding to the communication limit point Pc, and generates a control signal for activating the service brake 6B of the brake device 6 when the speed of the train T exceeds the safety limit speed or exceeds the speed limit corresponding to the communication limit point Pc.

Next, the operation of train control by the train control system 1 of this embodiment will be described in detail.
FIG. 10 is a conceptual diagram showing a basic processing cycle of train control by the train control system 1.
In the train control system 1 configured as described above, the train positions detected by the on-board control devices 4 mounted on each train T on the track R are transmitted to the ground control device 2 by wireless communication and collected, as shown in the upper right of Fig. 10. Then, the ground control device 2 determines safety stopping points Ps and communication limit points Pc corresponding to each train T, creates control commands instructing the safety stopping point distances and communication limit point distances as travel permission for each train T, and transmits the control commands to the on-board control devices 4 of each train T by wireless communication, as shown in the lower right of Fig. 10.

In the on-board control device 4 of each train T that receives a control command from the ground side, as shown on the left side of Figure 10, a first speed inspection pattern V1 corresponding to the safety stop point Ps and a second speed inspection pattern V2 corresponding to the communication limit point Pc are created, and braking control of each train T is performed according to the results of the speed inspection of the first and second speed inspection patterns V1 and V2, and the on-track position of each train T is detected again. This series of processes between the ground and on board is repeatedly executed at a predetermined period C, for example, 0.5 seconds.

Here, a detailed description will be given of the specific process flows of the ground control device 2 and the on-board control device 4 in the basic process cycle of train control by the train control system 1 as described above.
Fig. 11 is a flowchart showing an example of a specific process executed by the ground control device 2. Fig. 12 is a flowchart showing an example of a specific process executed by the on-board control device 4 of each train T.

First, in step S100 of FIG. 11, in the ground control device 2, information indicating the on-track position detected by the on-board control device 4 of each train T on the track R is transmitted from the on-board radio equipment 5 of each train T, received by each wayside radio equipment 3, and collected in the train position update unit 20 of the ground control device 2. Then, in the next step S110, the train position update unit 20 determines the on-track positions of all trains T on the track R while referring to information related to the ground coils in the ground database, and updates the train position information stored on the ground side.

In the next step S120, the stop point determination unit 21 uses the train position information updated in step S110, the current indication information of each signal S installed along the track, and the position information of the end point of the track R to determine a safety stop point Ps corresponding to each train T on the track R. Then, in step S130, the stop point distance calculation unit 22 calculates the stop point distance from the leading position of each train T to the safety stop point Ps.

In parallel with the processing of steps S120 and S130, in step S140, the communication range determination unit 23 uses the train position information updated in step S110 and the communication range data corrected at the required monitoring period by the data correction unit 26 to determine the communication ranges Ac, Ac' corresponding to each wayside radio equipment 3. Then, in step S150, the communication limit point distance calculation unit 24 uses the communication ranges Ac, Ac' of each wayside radio equipment 3 to set the communication limit point Pc corresponding to each train T on the track R. In the following step S160, the communication range determination unit 23 calculates the communication limit point distance from the head position of each train T to the communication limit point Pc.

In the next step S170, the control command creation unit 27 creates a control command indicating the stopping point distance and communication limit point distance of each train T calculated in the above steps S130 and S160, and the control command transmission unit 28 sends a transmission signal indicating the control command to each wayside radio equipment 3. As a result, a radio signal including the control command from the ground control device 2 is transmitted from each wayside radio equipment 3 and received by the on-board radio equipment 5 of each train T on the track R.

In step S200 of FIG. 12, the on-board control device 4 of each train T transmits the control command received by the on-board radio equipment 5 from the ground control device 2 to the pattern creation unit 42. Then, in step S210, the pattern creation unit 42 creates a first speed check pattern V1 for stopping the train T at the safety stopping point Ps and a second speed check pattern V2 for stopping the train T at the communication limit point Pc according to the stopping point distance and communication limit point distance included in the control command.

In the next step S220, the speed detection unit 40 detects the speed of the train T using the output signal of the speed generator. Then, in step S230, the speed inspection unit 43 performs a speed inspection by comparing the first and second speed inspection patterns V1, V2 created in step S210 with the speed of the train T detected in step S220. At this time, the speed of the train T is compared individually with the safety limit speed and safety speed limit indicated by the first speed inspection pattern V1, and the speed limit corresponding to the communication limit point Pc indicated by the second speed inspection pattern V2.

In the next step S240, the speed inspection unit 43 determines whether the speed of the train T exceeds the pattern speed (safety limit speed, safety speed limit, or speed limit corresponding to the communication limit point) indicated by either the first or second speed inspection pattern V1, V2. If the speed of the train T exceeds the pattern speed (YES), the process proceeds to the next step S250, and if the speed of the train T is equal to or lower than the pattern speed (NO), the process proceeds to step S260. In step S250, the brake control unit 44 outputs a control signal to operate the brake device 6 of the train T to decelerate the train to below the pattern speed.

Here, the speed check and brake control processing in steps S230 to S250 will be described in detail with reference to a specific example shown in FIG. 13 and FIG.
In the specific example of FIG. 13, four down trains T1 to T4 are present in a section where three wayside radio facilities 3A to 3C are installed along the track R. The track R has a main line R1 and a branch line R2, and a point where the branch line R2 is connected to the main line R1 is provided between the wayside radio facilities 3A and 3B. A signal S1 is installed along the main line R1 and a signal S2 is installed along the branch line R2 before the point. In the situation illustrated in FIG. 13, a train T1 is present on the main line R1 before the wayside radio facility 3A, and a train T2 is installed on the branch line R2. The signal S1 in front of the train T1 is showing a proceeding aspect (g), and the signal S2 in front of the train T2 is showing a stop aspect (r). In addition, a train T3 is present on the main line R1 ahead of the point, straddling the wayside radio facility 3B, and a train T4 is present near the wayside radio facility 3B.

At this time, the safety stop point Ps1 corresponding to train T1 is in front of the rear end of train T3, which is preceding train T3 on main line R1, because signal S1 is in a proceeding state. The safety stop point Ps2 corresponding to train T2 is in front of the installation position of signal S2, because signal S2 is in a stop state. In addition, both trains T1 and T2 are located within the communication range Ac of wayside radio equipment 3A. Since the radio signal transmitted from wayside radio equipment 3B, which is in front of wayside radio equipment 3A, is blocked by train T3, there is a range between each wayside radio equipment 3A and 3B where wireless communication is impossible. Therefore, the limit point on the downstream side of the communication range Ac of wayside radio equipment 3A (corresponding to the second limit point P2 in FIG. 4) becomes the communication limit point Pc common to trains T1 and T2.

In the situation illustrated in FIG. 13, the on-board control device 4 of train T1 creates a first speed check pattern V1 corresponding to the safety stop point Ps1 as shown in the upper left of FIG. 14, and a second speed check pattern V2 corresponding to the communication limit point Pc as shown in the lower left of FIG. 14. The safety speed limit (dashed line) indicated by the first speed check pattern V1 and the speed limit (solid line) corresponding to the communication limit point Pc indicated by the second speed check pattern V2 are the same speed near the location of train T1 on the track. However, since the communication limit point Pc is located before the safety stop point Ps1, the deceleration curve of the speed limit corresponding to the communication limit point Pc indicated by the second speed check pattern V2 starts to decrease at an earlier stage than the deceleration curve of the safety speed limit. Therefore, in the speed check performed by the on-board control device 4 of train T1, the speed of train T1 (thick line on the left side of Figure 14) is the first to exceed the speed limit indicated by the second speed check pattern V2. As a result, the service brakes 6B of train T1 are activated, and deceleration control is performed so that train T1 stops by the communication limit point Pc.

On the other hand, in the on-board control device 4 of train T2, the pattern creation unit 42 creates a first speed check pattern V1 corresponding to the safety stop point Ps2 as shown in the upper right of FIG. 14, and a second speed check pattern V2 corresponding to the communication limit point Pc as shown in the lower right of FIG. 14. As in the case of train T1, the safety speed limit (dashed line) shown in the first speed check pattern V1 created for train T2 and the speed limit (solid line) corresponding to the communication limit point Pc shown in the second speed check pattern V2 are the same speed near the location of train T2. However, contrary to the case of train T1, since the safety stop point Ps2 is located before the communication limit point Pc, the deceleration curve of the safety speed limit starts to decrease at an earlier stage than the deceleration curve of the speed limit corresponding to the communication limit point Pc. For this reason, in the speed check performed by the on-board control device 4 of train T2, the speed of train T2 (thick line on the right side of FIG. 14) exceeds the safety speed limit first. This activates the service brakes 6B of train T2, and deceleration control is performed so that train T2 stops before safety stopping point Ps2. If the speed of train T2 exceeds the safety limit speed due to insufficient deceleration by the service brakes 6B, the emergency brakes 6A of train T2 are activated.

Returning to FIG. 12, once the speed inspection and brake control processes are performed in steps S230 to S250 as described above, in the following step S260, the train position detection unit 41 of the on-board control device 4 calculates the current location of the train on the line and updates the position information. Then, in step S270, a radio signal including the position information updated by the train position detection unit 41 is transmitted from the on-board radio equipment 5 and is received by wayside radio equipment 3 within the communication range.

Next, the effects of the train control system 1 of this embodiment will be described.
As described above, in the train control system 1 of this embodiment, the ground control device 2 determines the communication ranges Ac, Ac' of each wayside radio equipment 3 based on the position information of each train T on the track R, calculates the communication limit point distance (communication limit point information) of each train T, and wirelessly transmits the communication limit point distance together with the safety stopping point distance (stopping point information) to the on-board control device 4 of each train T. Then, the on-board control device 4 of each train T performs train control based on the received safety stopping point distance and communication limit point distance.

According to the train control system 1 of this embodiment, even if the communication ranges Ac, Ac' of each wayside radio equipment 3 change due to the movement of the controlled train and the movement of other trains ahead of it, the controlled train can be prevented from departing from the communication ranges Ac, Ac'. In other words, by performing train control that does not allow the controlled train to enter a section where wireless communication becomes unstable due to the presence of other trains, such as a tunnel or underground track section, it is possible to maintain a stable wireless communication environment between the ground and on-board. In addition, the train control system 1 of this embodiment does not require on-board wireless equipment to be installed at both the front and rear of the train as in the above-mentioned conventional technology, so it can also be used for freight trains, rescue trains, and the like. Therefore, according to the train control system 1 of this embodiment, a stable wireless communication environment that can be used for various trains can be used to reliably transmit information between the ground and on-board, thereby realizing safe train operation.

Furthermore, in the on-board control device 4 in the train control system 1 of this embodiment, the pattern creation unit 42 creates a first speed check pattern V1 corresponding to the safety stop point Ps and a second speed check pattern V2 corresponding to the communication limit point Pc. Then, the speed check unit 43 performs speed checks using the first speed check pattern V1 and the second speed check pattern V2 independently, and the brake control unit 44 controls the brake device 6 of the train T according to the logical sum of the speed check results. With such an on-board control device 4, it is possible to perform brake control to operate the train T more safely while reliably maintaining a stable wireless communication environment between the ground and the on-board.

In addition, in the ground control device 2 in the train control system 1 of this embodiment, the communication range determination unit 23 determines the actual communication ranges Ac, Ac' of each wayside radio equipment 3 using the communication range data corresponding to the type of train T and the running direction stored in the data storage unit 25. With such a ground control device 2, the communication ranges Ac, Ac' of each wayside radio equipment 3 can be accurately determined corresponding to the various trains running on the track R, and the communication limit point distance of each train T can be calculated with high accuracy. In addition, the data correction unit 26 corrects the communication range data in the data storage unit 25 according to the change over time in at least one of the reception power and the communication error rate in the wireless communication between each wayside radio equipment 3, making it possible to flexibly respond to the deterioration of communication performance due to aging of each wayside radio equipment 3 and changes in the surrounding environment.

Although one embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and further modifications and variations are possible based on the technical concept of the present invention.

For example, in the above embodiment, an example was described in which the actual communication ranges Ac, Ac' of each wayside radio equipment 3 determined by the communication range determination unit 23 of the ground control device 2 are used to set the communication limit point Pc of each train T and calculate the communication limit point distance. In relation to this, since the communication ranges Ac, Ac' of each wayside radio equipment 3 are managed by the communication range determination unit 23, the ground control device 2 can acquire information on the redundancy of the communication path (the number of wayside radio equipment 3 that can communicate) at the location of each train T on the track R at any time. Therefore, by referring to this information, if the redundancy of the communication path is low, the number of transmissions of the control command may be increased in advance. This makes it possible to reduce communication errors with the on-board control device 4 of the train T with a low redundancy of the communication path. Alternatively, by referring to the above information, the communication limit point may be determined so that at least two communication paths are maintained for each train T on the track R. This makes it possible to prepare for a sudden failure of the wayside radio equipment 3.

In the above embodiment, an example has been described in which the ground control device 2 provides the on-board control device 4 of each train T with the stopping point distance and the communication limit point distance, but the method and format of providing the information on the safety stopping points and the communication limit points is not limited to the above example. For example, map information of the track R may be stored in the on-board database of the on-board control device 4, and the ground control device 2 may provide the on-board control device 4 with the position information of the safety stopping points and the communication limit points, and the on-board control device 4 may calculate the distances to the safety stopping points and the communication limit points and create a speed inspection pattern corresponding to each of them.

In addition, in the above-mentioned embodiment, a configuration example in which on-board radio equipment 5 is provided at the front of each train T has been shown, but the present invention is also effective in a system in which on-board radio equipment is installed at the front and rear of a train to create a redundant configuration. When the present invention is applied to such a system in which on-board radio equipment is configured redundantly, in a situation in which the on-board radio equipment at the rear of the train fails, the situation becomes equivalent to each of the situations in the above-mentioned embodiment, and the same effect as in the above-mentioned embodiment can be obtained. Alternatively, if the technical concept of the present invention is applied to a system in which on-board radio equipment is configured redundantly and the on-board radio equipment at the front fails, it is possible to avoid radio communication problems with the preceding train. This will be briefly explained with reference to FIG. 15.

Figure 15 shows a situation where an upbound train T1 is running behind an upbound train T2 whose on-board radio equipment at the front has broken down. In the situation shown in Figure 15, when the following train T1 enters the communication range Ac" of the wayside radio equipment 3A that is located closest to the rear of the preceding train T2, there is a possibility that wireless communication between the preceding train T2 and the wayside radio equipment 3A will be impaired. At this time, the ground control device 2 can calculate the distance d1 between train T1 and train T2, and the distance d2 from the rear end of train T2 to the limit point on the downlink side of the communication range Ac" of the wayside radio equipment 3A (corresponding to the fourth limit point P4 in Figure 4). Furthermore, the ground control device 2 can also use the distances d1 and d2 to calculate the distance d3 (d3 = d1 - d2) to the limit point at which train T1 does not interfere with the wireless communication of train T2. The ground control device 2 then compares the calculated distance d3 with the distance to the communication limit point of train T1 (the limit point on the uphill side of the communication range Ac" of the wayside radio equipment 3A), sets the point closer to train T1 as the actual communication limit point of train T1, and transmits the communication limit point information from the ground control device 2 to the on-board control device 4 of train T1. This makes it possible to avoid wireless communication problems with the preceding train T2.

In the above embodiment, an example was described in which the deceleration curve represented by the change in the safety speed limit indicated by the first speed check pattern V1 and the deceleration curve represented by the change in the speed limit corresponding to the communication limit point Pc indicated by the second speed check pattern V2 are set to be the same, but it is also possible to set each deceleration curve differently, that is, to create a speed check pattern in which the brake rates are different for the safety stop point Ps and the communication limit point Pc. In this case, train control can be performed according to the speed check pattern corresponding to the point on the near side (closer to the front end of the train to be controlled) between the safety stop point Ps and the communication limit point Pc.

1...Train control system, 2...Ground control device (ground device), 3...Wayside radio equipment (radio station), 4...On-board control device, 5...On-board radio equipment, 6...Brake device, 6A...Emergency brake, 6B...Normal brake, 20...Train position update unit, 21...Stop point determination unit, 22...Stop point distance calculation unit, 23...Communication range determination unit, 24...Communication limit point distance calculation unit, 25...Data storage unit, 26...Data correction unit, 27...Control command creation unit, 28...Control command transmission unit, 30, 50...Radio transmission and reception unit, 31...Ground antenna, 40...Speed detection unit, 41...Train position detection unit, 42...Pattern creation unit, 43...Speed inspection unit, 44...Brake control unit, 51...On-board antenna, Ac, Ac'...Communication range, Pc...Communication limit point, Ps...Safety stopping point, R...Track, T...Train, V1...First speed inspection pattern, V2...Second speed inspection pattern

Claims (6)

A train control system that wirelessly transmits safety stop point information from a ground device to an on-board device of a train via a plurality of radio stations installed along a track,
The ground device determines the communication range of each radio station based on the train position on the track, and wirelessly transmits to the on-board device information on a communication limit point at which the train is out of the communication range of all radio stations ahead of the train;
The on-board equipment controls the train based on the received stop point information and communication limit point information. The train control system of claim 1, wherein the on-board device creates two speed check patterns corresponding to the received stop point information and communication limit point information, respectively, performs speed checks using each speed check pattern independently, and controls train brakes according to the logical sum of the results of each speed check. The on-board device includes:
a speed detection unit for detecting a running speed of the train itself;
a pattern creation unit that creates a first speed check pattern corresponding to the stop point and a second speed check pattern corresponding to the communication limit point according to the stop point information and the communication limit point information received from the ground device via each of the radio stations;
a speed check unit that determines whether or not the running speed of the train itself detected by the speed detection unit exceeds each of the first and second speed check patterns created by the pattern creation unit;
a brake control unit that controls a train brake in accordance with a first or second speed check pattern when the speed check unit determines that the running speed of the train exceeds at least one of a first or second speed check pattern;
The train control system of claim 2 , comprising: The ground device includes:
a train position update unit that receives information wirelessly transmitted from the on-board device of each train on a track via each of the radio stations and updates position information of each of the trains using the received information;
a stop point determination unit that determines a safety stop point corresponding to each of the trains based on the position information of each of the trains updated by the train position update unit, the current indication information of signals installed along the track, and the position information of a track end point;
a communication limit point determination unit that calculates an actual communication range of each of the radio stations based on the position information of each of the trains updated by the train position update unit and communication range data corresponding to the communication performance of each of the radio stations, and determines a communication limit point corresponding to each of the trains;
a control command transmitting unit that wirelessly transmits, via each of the radio stations, a control command including the stop point information indicating the stop point determined by the stop point determining unit and the communication limit point information indicating the communication limit point determined by the communication limit point determining unit, to the on-board equipment of each of the trains;
The train control system of claim 1 . The train control system according to claim 4, wherein the communication limit point determination unit determines the actual communication range of each of the radio stations using the communication range data corresponding to the type and running direction of each of the trains. The train control system according to claim 4, further comprising a data correction unit that corrects the communication range data in response to changes over time in at least one of the reception power and the communication error rate in the wireless communication between the wireless stations.