A rail transit door system network architecture and network communication method

Abstract

The present invention discloses a rail transit door system network architecture and network communication method. All gate control units in the door system are chain-connected, and the gate control units at the head and tail are connected to real-time Ethernet switches to form a ring network topology to complete the interaction of control information and maintenance information; the gate control unit and the two real-time Ethernet switches respectively form two external network planes, and the two external network planes are mutually redundant; the real-time Ethernet switch is connected to TCMS, and all gate control units communicate directly with TCMS. The DCU of the present invention is standardized, and there is no need to distinguish between master and slave DCUs. The DCU can communicate directly with TCMS; the network architecture has ring network redundancy, link redundancy and bypass relay technology, which can prevent two-point failures and has high reliability.

Description

Technical Field

[0001] The present invention belongs to the technical field of network communication, and in particular to a network architecture and a network communication method for a rail transit door system. Background Art

[0002] Existing rail transit vehicles generally use the multifunction vehicle bus MVB (Multifunction Vehicle Bus) or standard Ethernet as the vehicle backbone network. With the rapid development of the industry, the network control functions of vehicles are constantly expanding, and the diagnostic data is increasing, resulting in higher requirements for bandwidth and real-time performance of vehicle networks. The MVB bus has high real-time performance, but the communication rate is only 1.5Mbps, which cannot meet the requirements of large bandwidth; standard Ethernet has a large bandwidth, but the transmission is not deterministic and cannot guarantee the real-time performance of control data. In order to meet the requirements of large bandwidth and high real-time performance, vehicle networks are gradually being upgraded to real-time Ethernet.

[0003] Take the door system as an example. Due to the large number of door system devices, in order to ensure bandwidth and real-time requirements, the door system itself forms an intranet, and each car only retains two nodes connected to the TCMS (Train Control and Management System) network. In the existing rail transit vehicle Ethernet architecture, the door system has its own intranet because of the large number of door control units (DCUs) and the long distance between DCUs. Figure 1 As shown. DCU distinguishes between master and slave. Each carriage has two master door control units MDCU, and the rest are slave door control units LDCU. The two MDCUs are connected to the train Ethernet switch in a star shape, and the MDCU and LDCU are connected in a chain shape. The MDCU has a gateway function. Only the port on the MDCU connected to the switch can communicate with TCMS. The LDCU cannot communicate with TCMS. The DCU lacks standardization. Summary of the invention

[0004] Purpose of the invention: The purpose of the present invention is to provide a rail transit door system network architecture and network communication method in which all DCUs and TCMSs can communicate directly and DCUs are standardized.

[0005] Technical solution: The network architecture of the rail transit door system of the present invention includes a door control unit. All the door control units in the door system are chain-connected. The door control units at the head and tail are connected to real-time Ethernet switches to form a ring network topology to complete the interaction of control information and maintenance information. The door control unit and the two real-time Ethernet switches respectively form two external network planes, and the two network planes are redundant with each other.

[0006] The real-time Ethernet switch is connected to the TCMS, and all door control units communicate directly with the TCMS.

[0007] Furthermore, each of the external network planes logically disconnects the loop through a ring network redundancy protocol, and each gating unit sets a bypass relay between two network ports in the same external network plane. Each gating unit detects the link in real time, and when a breakpoint occurs, the logically disconnected loop is closed to achieve breakpoint detection and link switching.

[0008] Furthermore, the gate control unit has a built-in Switch module;

[0009] The Switch module includes a Switch, which forms two internal network planes through logical isolation, and respectively forms two external network planes with the two real-time Ethernet switches; or,

[0010] The Switch module includes two Switch switches, which form two internal network planes through physical isolation and respectively form two external network planes with the two real-time Ethernet switches.

[0011] Furthermore, all the door control units directly communicate with the TCMS including:

[0012] When TCMS sends data, the gate control unit connected to the two real-time Ethernet switches receives two data channels at the same time and forwards them to the next gate control unit. After the forwarding is completed, the gate control unit eliminates duplicate frames and sends one data channel to the CPU.

[0013] When a gate control unit uploads data, it copies the data and sends it to adjacent gate control units. Each real-time Ethernet switch on the external network plane receives one channel of data and forwards it to TCMS.

[0014] Furthermore, the network topology between the two real-time Ethernet switches includes a ring network, a linear network or a link aggregation network.

[0015] In the network communication method for rail transit door system of the present invention, the real-time Ethernet switch is connected to the TCMS, and all the door control units in the door system communicate directly with the TCMS; all the door control units in the door system are chain-connected, and the door control units at the head and the tail are connected to the real-time Ethernet switch to form a ring network topology, and the interaction of control information and maintenance information is completed;

[0016] The gate control unit and the two real-time Ethernet switches respectively form two external network planes, and the two network planes are redundant to each other.

[0017] Furthermore, each of the external network planes logically disconnects the loop through a ring network redundancy protocol, and each gating unit sets a bypass relay between two network ports in the same external network plane. Each gating unit detects the link in real time, and when a breakpoint occurs, the logically disconnected loop is closed to achieve breakpoint detection and link switching.

[0018] Furthermore, the gate control unit has a built-in Switch module;

[0019] The Switch module includes a Switch, which forms two internal network planes through logical isolation, and respectively forms two external network planes with the two real-time Ethernet switches; or,

[0020] The Switch module includes two Switch switches, which form two internal network planes through physical isolation and respectively form two external network planes with the two real-time Ethernet switches.

[0021] Furthermore, when TCMS sends data, the gate control unit connected to the two real-time Ethernet switches receives two data paths at the same time and forwards them to the next gate control unit. After the forwarding is completed, the gate control unit eliminates duplicate frames and sends one data path to the CPU.

[0022] When a gate control unit uploads data, it copies the data and sends it to adjacent gate control units. Each real-time Ethernet switch on the external network plane receives one channel of data and forwards it to TCMS.

[0023] Furthermore, the network topology between the two real-time Ethernet switches includes a ring network, a linear network or a link aggregation network.

[0024] Beneficial effects: Compared with the prior art, the advantages of the present invention are: (1) The DCU of the present invention is standardized, and there is no need to distinguish between master and slave DCUs. The DCU can communicate directly with the TCMS; (2) The network architecture of the present invention has ring network redundancy, link redundancy and bypass relay technology, which can prevent two-point failures and has high reliability; (3) The present invention uses a safe, reliable and deterministic real-time Ethernet, which has both the deterministic and real-time requirements of the field industrial bus and the large bandwidth requirements of the standard Ethernet, and can simultaneously transmit control data and maintenance data to achieve multi-network integration. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a topological diagram of the vehicle door system compartment network architecture in the prior art;

[0026] Figure 2 This is a network architecture diagram of the door system of the present invention;

[0027] Figure 3This is a schematic diagram of the DCU internal network isolation of the present invention;

[0028] Figure 4 Schematic diagram of link switching within a network plane in an embodiment of the present invention;

[0029] Figure 5 This is a data flow diagram of TCMS sending data under normal circumstances in an embodiment of the present invention;

[0030] Figure 6 This is a data flow diagram of TCMS sending data under abnormal circumstances in an embodiment of the present invention;

[0031] Figure 7 This is a flow chart of DCU uploading data under normal circumstances in an embodiment of the present invention;

[0032] Figure 8 This is a flow chart of DCU uploading data under abnormal circumstances in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The technical solution of the present invention is further described below in conjunction with the accompanying drawings.

[0034] like Figure 2 As shown in the figure, the rail transit door system network architecture includes DCU and real-time Ethernet switch. The "=" line and "-" line in the figure represent two different networks. Taking the door system as an example, a train-level secure real-time Ethernet is set up, all DCUs in the carriage are chain-connected, and the head and tail DCUs are connected to the vehicle real-time Ethernet switch to form a ring network topology. All DCUs can communicate directly with TCMS without distinguishing between master and slave DCUs, and the degree of standardization is high.

[0035] The network topology between train real-time Ethernet switches can be a ring network, a linear network or a link aggregation network. Real-time Ethernet also completes the interaction of control information and maintenance information.

[0036] By setting up dual network planes, seamless redundancy of the dual network planes can be achieved through the IEEE 802.1CB protocol or similar equivalent protocols. A failure of a single network plane does not affect the other network plane.

[0037] DRP or similar equivalent ring network redundancy protocols are used in a single ring network plane to disconnect the loop logic and prevent the occurrence of network storms in the plane. Each DCU detects the link in real time. When a breakpoint occurs, the originally logically disconnected loop is reconnected to achieve breakpoint detection and link switching.

[0038] like Figure 3As shown in (a), (b) and (c), the DCU has a built-in switch module with four network interfaces. A built-in switch can be logically isolated into two network planes through technologies such as VLAN (Virtual Local Area Network), or physically isolated through two built-in switches.

[0039] After TCMS sends data, the switch module of the DCU connected to the two train real-time Ethernet switches receives two data at the same time and forwards it to the next DCU. After the forwarding is completed, the switch module eliminates duplicate frames and sends one data to the CPU of this DCU.

[0040] When the DCU uploads data to TCMS, the switch module of the DCU will simultaneously copy the data four times and forward it to two adjacent DCUs. Since a single network plane uses the ring network redundancy protocol to disconnect the loop logic, the train real-time Ethernet switch of each network plane will only receive one DCU data and forward the data to TCMS.

[0041] Add a bypass relay between the two network ports on the same network plane on the DCU to prevent the situation where the failure of two DCUs causes all devices between the failed DCUs to be disconnected on both network planes.

[0042] DCU has information security functions to ensure the confidentiality and integrity of data.

[0043] Secure real-time Ethernet can adopt: TSN (Time-Sensitive Networking) technology, 5G technology, secure wireless communication technology or other secure communication technologies.

[0044] by Figure 4 This example illustrates the link failure handling within a single network plane. By default, DCU9 and DCU10 are logically disconnected, represented by a dotted line, and all DCUs can communicate with the real-time Ethernet switch, such as Figure 4 When the link between DCU3 and DCU5 is physically disconnected, DCU9 and DCU10 close the link between them, and all DCUs can still communicate with the real-time Ethernet switch, as shown in (a). Figure 4 As shown in (b) in the figure. If two links are physically disconnected, the DCUs between the breakpoints need to rely on another network plane for communication.

[0045] by Figure 5 , Figure 6Take the data processing sent by TCMS to DCU as an example. By default, the link between DCU9 and DCU10 is logically disconnected. Each DCU forwards the two received data to the next DCU. Each DCU removes the duplicate frames received later and sends them to the local CPU. The data transmission direction is as follows: Figure 5 The real-time Ethernet switch sends the data to the DCU connected to it, namely DCU1 or DCU2, and then forwards it to each DCU in turn.

[0046] In an abnormal situation, assuming that the link between DCU3 and DCU5 in the B plane is physically disconnected, the data transmission direction is as follows Figure 6 As shown. Due to a breakpoint in the B plane, the logical link between DCU9 and DCU10 is closed, DCU3 receives data forwarded from DCU1, and DCU5 receives data forwarded from DCU7. Data in the A plane is sent normally.

[0047] by Figure 7 , Figure 8 Take the data processing of DCU uploading to TCMS as an example. DCU7 needs to send data to TCMS. By default, the link between DCU9 and DCU10 is logically disconnected. DCU7 copies the data four times and sends it to both DCUs through four network ports at the same time. Since the link between DCU9 and DCU10 is logically disconnected, the train real-time Ethernet switch on each network plane will only receive one DCU data and forward the data to TCMS. The data transmission direction is as follows: Figure 7 The data in DCU7 is uploaded to TCMS via DCU5, DCU3 and DCU1 in sequence.

[0048] In an abnormal situation, assuming that the link between DCU3 and DCU5 on the B plane is physically disconnected, the data transmission direction is as follows Figure 8 As shown in the figure, due to the breakpoint in the B plane, the logical link between DCU9 and DCU10 is closed, and the data in DCU7 is uploaded to TCMS through DCU9, DCU10, DCU8, DCU6, DCU4 and DCU2 in sequence; in the A plane, the data in DCU7 is uploaded to TCMS through DCU5, DCU3 and DCU1 in sequence.

[0049] In the network communication method for rail transit door system of the present invention, the real-time Ethernet switch is connected to the TCMS, and all the door control units in the door system communicate directly with the TCMS; all the door control units in the door system are chain-connected, and the head and tail door control units are connected to the real-time Ethernet switch to form a ring network topology, and the interaction of control information and maintenance information is completed; the door control unit and the two real-time Ethernet switches respectively form two external network planes, and the two network planes are redundant to each other.

[0050] Each external network plane logically disconnects the loop through the ring network redundancy protocol. Each gating unit sets a bypass relay between two network ports in the same external network plane. Each gating unit detects the link in real time. When a breakpoint occurs, the logically disconnected loop is closed to achieve breakpoint detection and link switching.

[0051] The door control unit has a built-in Switch module; the Switch module includes a Switch, which forms two internal network planes through logical isolation, and respectively forms two external network planes with two real-time Ethernet switches; or, the Switch module includes two Switches, which form two internal network planes through physical isolation, and respectively form two external network planes with two real-time Ethernet switches.

[0052] When TCMS sends data, the gating unit connected to the two real-time Ethernet switches receives two data channels at the same time and forwards them to the next gating unit. After the forwarding is completed, the gating unit eliminates duplicate frames and sends one data channel to the CPU.

[0053] When a gate control unit uploads data, it copies the data and sends it to adjacent gate control units. Each real-time Ethernet switch on the external network plane receives one channel of data and forwards it to TCMS.

[0054] The network topology between two real-time Ethernet switches includes a ring network, a linear network, or a link aggregation network.

Claims

1. A rail transit door system network architecture, characterized in that: It includes a gate control unit, all the gate control units in the door system are connected in a chain, the gate control units at the head and tail are connected to the real-time Ethernet switch, forming a ring network topology, completing the interaction of control information and maintenance information; the gate control unit and the two real-time Ethernet switches respectively form two external network planes, and the two external network planes are redundant to each other; The real-time Ethernet switch is connected to the TCMS, and all the gate control units communicate directly with the TCMS; the gate control unit has a built-in Switch module; The Switch module includes a Switch, which forms two internal network planes through logical isolation, and respectively forms two external network planes with the two real-time Ethernet switches; or, The Switch module includes two Switch switches, which form two internal network planes through physical isolation and respectively form two external network planes with the two real-time Ethernet switches.

2. The rail transit door system network architecture according to claim 1, characterized in that: Each of the external network planes logically disconnects the loop through a ring network redundancy protocol. Each gating unit sets a bypass relay between two network ports in the same external network plane. Each gating unit detects the link in real time and closes the logically disconnected loop when a breakpoint occurs.

3. The rail transit door system network architecture according to claim 1, characterized in that: The direct communication between all gate control units and TCMS includes: When TCMS sends data, the gate control unit connected to the two real-time Ethernet switches receives two data channels at the same time and forwards them to the next gate control unit. After the forwarding is completed, the gate control unit eliminates duplicate frames and sends one data channel to the CPU. When a gate control unit uploads data, it copies the data and sends it to adjacent gate control units. Each real-time Ethernet switch on the external network plane receives one channel of data and forwards it to TCMS.

4. The rail transit door system network architecture according to claim 1, characterized in that: The network topology between the two real-time Ethernet switches includes a ring network, a linear network or a link aggregation network.

5. A rail transit door system network communication method, characterized in that: The real-time Ethernet switch is connected to the TCMS, and all the door control units in the door system communicate directly with the TCMS; all the door control units in the door system are chain-connected, and the door control units at the head and tail are connected to the real-time Ethernet switch to form a ring network topology, completing the interaction of control information and maintenance information; The gate control unit and the two real-time Ethernet switches respectively form two external network planes, and the two network planes are mutually redundant; the gate control unit has a built-in Switch module; The Switch module includes a Switch, which forms two internal network planes through logical isolation, and respectively forms two external network planes with the two real-time Ethernet switches; or, The Switch module includes two Switch switches, which form two internal network planes through physical isolation and respectively form two external network planes with the two real-time Ethernet switches.

6. The rail transit door system network communication method according to claim 5, characterized in that: Each of the external network planes logically disconnects the loop through a ring network redundancy protocol. Each gating unit sets a bypass relay between two network ports in the same external network plane. Each gating unit detects the link in real time and closes the logically disconnected loop when a breakpoint occurs.

7. The rail transit door system network communication method according to claim 5, characterized in that: When TCMS sends data, the gate control unit connected to the two real-time Ethernet switches receives two data channels at the same time and forwards them to the next gate control unit. After the forwarding is completed, the gate control unit eliminates duplicate frames and sends one data channel to the CPU. When a gate control unit uploads data, it copies the data and sends it to adjacent gate control units. Each real-time Ethernet switch on the external network plane receives one channel of data and forwards it to TCMS.

8. The rail transit door system network communication method according to claim 5, characterized in that: The network topology between the two real-time Ethernet switches includes a ring network, a linear network or a link aggregation network.

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