KR101081843B1 - Network communication apparatus of railway car - Google Patents

Abstract

The present invention relates to a network communication device of a railway vehicle.

The network communication apparatus of a railway vehicle according to the present invention reads and writes data from a transceiver unit for transmitting and receiving data on a network through a communication line connecting the railway vehicles, a repeater for amplifying and outputting data received from the transceiver unit, and a repeater. It is configured to include a communication control unit, the repeater is characterized in that the data transmitted from the transceiver unit to the communication control unit and at the same time re-output on the network through the communication line via the transceiver unit.

According to the present invention, it is possible to effectively respond to various needs such as increasing the transmission distance and the number of nodes by eliminating the limitation of the transmission distance and the total number of nodes by using the arcnet repeater for the main communication dedicated to the long train. When a failure occurs, there is an effect of providing a network communication device of a railway vehicle that can actively control the communication connection of a failed node.

Rolling stock, transceivers, repeaters, communication controls, bypass relays

Description

Network communication device of rolling stock {NETWORK COMMUNICATION APPARATUS OF RAILWAY CAR}

The present invention relates to a network communication device of a railway vehicle. More specifically, the present invention compensates for the problem of distance limitation among inter-vehicle communication methods used in railway vehicles, for example, when applied to 20 or more long-range trains of the railway vehicle to share all data of the vehicle with each other It relates to a network communication device.

In general, railway vehicles operate in a unit formed by connecting a plurality of vehicles, and long-range trains in which more than 20 vehicles are configured in a single unit are also operated.

As such, as the number of vehicles that constitute a single train increases, problems such as distance limitations make it difficult to smoothly perform communication between vehicles.

1 is a diagram illustrating a network communication method of a conventional railway vehicle.

Referring to FIG. 1, in the related art, a method of performing vehicle-to-vehicle communication using a communication controller and a transceiver under the control of a main control processor has been used.

However, according to the conventional method, various problems occur as follows.

1. Problems with distance limitation

The conventional method has a constraint of up to 12 nodes and a communication distance of 330 m when using a bus topology. In addition, even if other topologies such as ring, star, and tree are used, the limitation of bandwidth causes the limitation of distance and the total number of nodes due to the limitation of data transmission in the same cable.

As the cause of the long distance communication and the number of node constraints is basically a synchronized communication method, it is limited by the effect of voltage decrease, waveform distortion and transmission delay caused by the distance.

2. Communication cable screening limit

Optimizing long distance communication requires the purchase and use of expensive, expensive cables that take into account the impedance generated at high frequencies (2.5Mbps). In addition, due to the use of a special cable is difficult to work during installation, thereby increasing the operating cost.

3. Difficulty in selecting transceiver and cable connectors

According to Arcnet, transceivers and transmission cables for long distance transmissions must be paired. For example, to use a transceiver for a coaxial cable, you must use a coaxial cable such as RG-62 / u. Figure 2 shows the maximum number of nodes and transmission distance per arcnet communication cable / connector.

However, even in this case, although the distance can be transmitted 300m, the total number of nodes is limited (maximum 8 nodes). When designing a train communication network in the above manner, there is a limit that only 8 vehicles can be designed, and in the case of 10 vehicles, a different communication method should be selected.

If the topology changes, the transceiver must be changed accordingly, so the design must be changed and it is difficult to immediately respond to various consumer demands.

4. It is impossible to block communication of a broken communication board.

According to the conventional method, the transceiver is directly connected to the communication line without a separate switch. Therefore, the blocking control could not be performed when the error data due to the failure or abnormality of the communication board entered the network.

For example, if wrong data is generated due to an error in the communication control unit, the main control processor cannot cleanly separate its node from the communication line. As a result, communication failures between vehicles occur.

The present invention eliminates the limitation of the transmission distance and the total number of nodes by using the arcnet repeater as the main communication for long-term trains, and the network communication apparatus of the railway vehicle that can effectively respond to various needs such as increasing the transmission distance and the number of nodes of the consumer. To provide a technical problem.

Another object of the present invention is to provide a network communication apparatus for a railway vehicle that can actively control communication connections of a failed node when a failure occurs in some nodes.

Network communication apparatus for a railway vehicle according to the present invention for achieving the technical problem is a transceiver unit for transmitting and receiving data on the network through a communication line connecting the railway vehicle, a repeater for amplifying and outputting the data received from the transceiver unit and And a communication control unit configured to read data from the repeater and perform a write operation, wherein the repeater transfers the data received from the transceiver unit to the communication control unit, and at the same time, passes through the transceiver unit on the network through the communication line. It is characterized by reprinting.

The transceiver unit may include a first transceiver and a second transceiver independently connected to the repeater.

The apparatus may further include a bypass relay unit connecting the first transceiver to the second transceiver to mediate direct data transfer between the first transceiver and the second transceiver.

The bypass relay unit mediates data transmission between the communication line and the second transceiver in a normal bypass state and a first bypass relay that mediates data transmission between the communication line and the first transceiver in a normal close state. And a second bypass relay, wherein the first and second bypass relays are configured to change internal contacts so that the first transceiver and the second transceiver are directly connected to each other according to a bypass control signal.

According to the present invention, the long-range train dedicated main communication by using the Arcnet repeater eliminates the limitation of the transmission distance and the total number of nodes, the network of the railway vehicle that can effectively respond to various needs, such as increasing the transmission distance and the number of nodes of consumers There is an effect that a communication device is provided.

In addition, when a failure occurs in some nodes, there is an effect that a network communication device of a railway vehicle that can actively control the communication connection of the failed node is provided.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a diagram illustrating a network communication apparatus for a railway vehicle according to an embodiment of the present invention.

Referring to FIG. 3, a network communication apparatus of a railway vehicle according to an embodiment of the present invention includes a transceiver unit 10, a repeater 20, a communication control unit 30, and a bypass relay unit 40. .

The transceiver unit 10 is a means for transmitting and receiving data on a network through a communication line connecting railway vehicles. More specifically, the transceiver unit 10 receives data on the network and transmits the data to the communication control unit 30 to be described later or loads the data received from the control unit on the network.

The transceiver unit 10 includes a first transceiver 12 and a second transceiver 14 independently connected to the repeater 20 to be described later.

The repeater 20 is a means for amplifying and outputting data received from the transceiver unit 10.

The repeater 20 is configured to transfer the data received from the transceiver unit 10 to the communication control unit 30 and to re-output it on the network through the communication line via the transceiver unit 10.

The communication control unit 30 performs overall communication control for performing communication with other devices, and continuously reads and writes data from the repeater 20.

The bypass relay unit 40 is a means for connecting the first transceiver 12 and the second transceiver 14 to mediate the direct transfer of data between the first transceiver 12 and the second transceiver 14.

The bypass relay unit 40 includes a first bypass relay 42 and a second bypass relay 44.

Hereinafter, the operation of the bypass relay unit 40 will be described by dividing the normal mode and the failure mode.

<Normal Mode>

The normal mode is an operation mode in which there is no error such as when there is wrong data due to an error of the communication control unit 30.

In this normal mode, the first bypass relay 42 maintains a normal close state to mediate data transfer between the communication line and the first transceiver 12. In addition, the second bypass relay 44 also maintains a normal closed state to mediate data transfer between the communication line and the second transceiver 14.

<Failure Mode>

The failure mode is an operation mode in which an error such as a board failure or a loss of power occurs when there is wrong data due to an error of the communication control unit 30. In this failure mode, the main control processor generates a bypass control signal to operate the first and second bypass relays 42 and 44.

When the bypass control signal is input, 1) a contact line connecting the communication line and the first transceiver 12 among the internal contacts of the first and second bypass relays 42 and 44, the communication line and the second transceiver ( The contact connecting 14) is turned off so that the electrical connection between the communication line and the transceiver unit 10 is cut off. 2) At the same time, the contacts connecting the first transceiver 12 and the second transceiver 14 among the internal contacts of the first and second bypass relays 42 and 44 are turned on so that the first transceiver 12 and the first transceiver 12 are turned on. The two transceivers 14 are directly electrically connected.

4 is a diagram illustrating an example in which a network communication apparatus for a railway vehicle according to an embodiment of the present invention is implemented on a communication board.

Hereinafter, an implementation example in terms of hardware and software will be described with reference to FIG. 4.

1. Communication board hardware design

(1) VMEbus interface

To control the VMEMU board through the VMEbus, VMEbus address / data and some control signals are passed through the buffer to the VMEMU board.

The five bits of A31 to A27 of the VMEbus address are always compared to the VMEbus ID setting slide switch (SLIDE SWITCH) on the VMEMU board. If the upper 5 bits of the VMEbus address match the ID of the VMEMU board, it knows whether the current VMEbus cycle is on the VMEMU board. In addition, the programmable logic device (PLD) of the VMEMU board generates the MYBD * signal, which is a board selection signal, to control the internal circuit of the VMEMU. It generates a DTACK * signal on the VMEbus to terminate the current VMEbus cycle with the VMEbus Master board. When VRAMbus Master board accesses DPRAM, it supports EVEN / ODD BYTE or WORD.

(2) PROCESSOR

For example, it uses the MPC860SR 50MHZ processor from Freescale Semiconductor and acts as the main control processor for the VCOMT board. Of the four SCC channels, SCC 1, 2, 3, and 4 channels are used as ports for RS-485 communication, and SCC 1 channel is shared with the Ethernet port. In SMC 1 and 2 channels, the SMC 1 channel is used as the CONSOLE port and the SMC 2 channel is not used. 32-bit address lines and 16-bit data lines are used for system memory and other I / O operations.

(3) PLD (Programmable Logic Device)

It performs address decoding (DECODING) function to allow DPRAM access in VMEMU board using VMEbus address and control signal, and generates DTACK signal which is VMEbus termination cycle. In addition, by appropriately controlling the signals of the CPU on the board to generate a signal to control the various devices.

(4) memory

The VARCT board is equipped with 32KB (= 16K * 16bits) DPRAM. This DPRAM is perceived as local memory that resides in the slave area of the VARCT board on the VMEbus. Control signals for accessing the local memory area via the VMEbus are generated in the PLD and operate in the VMEbus Standard Mode of 24-bit address and 16-bit data.

(5) ARCNET Node

There are two ARCNET nodes on the VARCT board. Each ARCNET node uses a communication control unit, for example, COM20020, which is an ARCNET controller of SMSC, and a repeater, for example, TMC2005, which is a repeater of TMC, and a transceiver, for example, HYC5000, which is a transceiver of TMC. do. The VMEbus master board accesses the DPRAM area of the VARCT board through the VMEbus. At this time, a certain area of the DPRAM is set as TX / RX buffer for each node for ARCNET communication.

2. Software design

Each ARCNET communication board is assigned a node number from the VMEbus master board. When a master node calls a slave node, the slave node puts corresponding data on the communication line (broad casting method). When the control code is put in the DPRAM register area, the DPRAM data is automatically sent through the communication line by the CPU of the Arcnet board. As if the VMEbus master board reads and writes only considering the DPRAM memory area, the Arcnet board's CPU (MPC860SR) has the values and controls the COM20020 to maintain communication.

The COM20020 reads and writes data from the repeater, and the Arcnet board's CPU places the value in the specified DPRAM. The repeater automatically reads the data value read from the previous node to the next node and reports the result to COM20020.

Bypass relays, which operate in the event of a board failure or power loss, remain normally closed and can control the VMEbus master board. Therefore, it is up to the control of the VMEbus master board to participate and communicate with the node.

Terminal relay used in both ends of communication maintains Normal Open state basically, can be controlled by VMEbus master board, and can be forced by installing jumper on the outside of the board. .

5 is a diagram illustrating an example in which a network communication apparatus for a railway vehicle according to an embodiment of the present invention is implemented in a group of 20 vehicles.

As a result of testing and configuring a communication network with 20 nodes 22 nodes as shown in FIG. 5, the time delay passing through the repeater and the time delay passing through the 20 nodes 22 nodes are time delays that do not affect the entire communication in units of ㎲. Could know. As a result of the test, the delay time between repeater input and output terminals is about 650ns, the delay time according to the length of the communication cable (about 30m) installed in one railway vehicle is 144ns, and the delay time according to the internal PCB pattern length (about 1m) is 4.8ns. ns, and the total delay time in the 20-carat formation was measured to be about 30 ms.

As described in detail above, according to the present invention, the main communication dedicated to the long-range train can be effectively applied to various demands such as increasing the transmission distance and the number of nodes by eliminating the limitation of the transmission distance and the total number of nodes by using the arcnet repeater. There is an effect that the network communication device of the railway vehicle can be provided.

In addition, when a failure occurs in some nodes, there is an effect that a network communication device of a railway vehicle that can actively control the communication connection of the failed node is provided.

In addition, by amplifying and using short-range communication using a repeater, communication is possible without using a special cable, and there is an advantage in manufacturing cost as the communication board itself.

Although the technical spirit of the present invention has been described above with reference to the accompanying drawings, this is intended to describe exemplary embodiments of the present invention by way of example and not to limit the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

1 is a diagram illustrating a network communication method of a conventional railway vehicle.

2 is a view showing the maximum number of nodes and transmission distance for each Arcnet communication cable / connector.

3 is a diagram illustrating a network communication apparatus for a railway vehicle according to an embodiment of the present invention.

4 is a diagram illustrating an example in which a network communication apparatus for a railway vehicle according to an embodiment of the present invention is implemented on a communication board.

5 is a diagram illustrating an example in which a network communication apparatus for a railway vehicle according to an embodiment of the present invention is implemented in a group of 20 vehicles.

***** Explanation of symbols for the main parts of the drawing *****

10: transceiver section 12: the first transceiver

14: second transceiver 20: repeater

30: communication control unit 40: bypass relay unit

42: first bypass relay 44: second bypass relay

Claims (4)

In the network communication device of a railway vehicle, Transceiver unit for transmitting and receiving data on the network through a communication line connecting the railway vehicles; A repeater for amplifying and outputting data received from the transceiver unit; And A communication controller which reads data from the repeater and performs a write operation; The transceiver unit includes a first transceiver and a second transceiver independently connected to the repeater, And a bypass relay unit connecting the first transceiver and the second transceiver to mediate data transfer directly between the first transceiver and the second transceiver. And the repeater transmits the data received from the transceiver unit to the communication control unit and re-outputs the data on the network through the communication line via the transceiver unit. delete delete The method according to claim 1, The bypass relay unit A first bypass relay for mediating data transfer between the communication line and the first transceiver in a normal close state; And A second bypass relay that mediates data transfer between the communication line and the second transceiver in a normal closed state, And the first and second bypass relays are configured to change internal contacts such that the first transceiver and the second transceiver are directly connected according to a bypass control signal.

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