Method for establishing traction control redundant network

Abstract

The invention provides a method for establishing a traction control redundant network, which comprises the following steps of: cascading local area networks in adjacent carriages through a first switch and a second switch preset in each carriage to form a double-channel communication Ethernet, and enabling the first switch and the second switch in the head carriage and the tail carriage of a train to be in communication connection to form a looped network; gateways are arranged in the head compartment and the tail compartment of the train respectively, and data forwarding between the train central control unit and all devices in the middle compartments is carried out through the gateways; the first switch and the second switch in the head compartment and the tail compartment of the train are connected with a third switch and a fourth switch in an original train-level backbone network of the train in a one-to-one correspondence mode to form a redundant communication network; and the first switch and the second switch in the head compartment and the tail compartment of the train are respectively in communication connection with the train central control units in the head compartment and the tail compartment of the train. According to the method, the redundancy of the vehicle control communication network can be improved, and the safety and reliability of vehicle operation are further improved.

Description

Technical Field

[0001] The invention relates to the field of locomotive traction control, and in particular to a method for establishing a traction control redundant network. Background Art

[0002] EMUs are responsible for the passenger transportation of major railway bureaus across the country, and the operating departments have high requirements for the smooth operation of the operating lines and the punctuality of the trains. EMUs generally operate in three reconnection modes: short, long or short. The master-slave control power car / control car (located at the front and rear of the car respectively) is connected through the train-level backbone network. When the backbone network fails, the control instructions and status information of the master-slave control power car / control car interconnection will not be transmitted, causing the entire EMU to be unable to operate normally. At present, the existing EMUs have not solved this problem. Reconnection hard wires are arranged throughout the entire train, and the emergency traction mode is switched through the conversion switch. The control information such as key occupation, pantograph raising, main disconnection, direction, traction braking, etc. is transmitted by hard wire level signals. Since hard wire signals are all level signals, analog quantities such as the driver controller level cannot be transmitted. Therefore, when the driver switches to emergency traction mode, the speed cannot be accurately controlled through the driver controller, and key information affecting driving such as traction and braking force cannot be displayed on the computer display screen. Usually, degraded operating modes such as speed limit and quasi-constant speed control are used to maintain operation.

[0003] With the iteration and upgrading of new technologies, the 200 km / h centralized power EMU with generational characteristics carries the important significance of comprehensively improving the intelligence and control performance of this series of products. It also puts forward requirements for comprehensively improving reliability and controllability for emergency traction mode, and urgently needs to improve in train integrated design, network topology architecture, functional redundancy configuration and other aspects. Summary of the invention

[0004] In order to improve the safety and reliability of traction control by reforming the existing EMU, the present invention proposes a method for forming a redundant traction control network, the method comprising: cascading the local area networks in adjacent carriages through the first switch and the second switch preset in each carriage to form a two-way communication Ethernet, and making the first switch in the head and tail carriages of the train communicate with the second switch to form a ring network; arranging gateways in the head and tail carriages of the train respectively so that the gateways can forward data between the train central control unit and various devices in the middle carriages; connecting the first switch and the second switch in the head and tail carriages of the train to the third switch and the fourth switch in the original train-level backbone network of the vehicle one by one to form a redundant communication network; and connecting the first switch and the second switch in the head and tail carriages of the train to the train central control unit in the head and tail carriages of the train respectively.

[0005] In one or more embodiments, a method of establishing a traction control redundant network of the present invention further includes: configuring the Ethernet according to the data format, packet rate and packet period in the train-level backbone network.

[0006] In one or more embodiments, a method of establishing a traction control redundant network of the present invention also includes: configuring a central slave control unit to send a first heartbeat message to a central master control unit through the gateway and multiple first switches, and configuring the Ethernet as a backup emergency traction control network to be put into use when a failure occurs in the train-level backbone network.

[0007] In one or more embodiments, a method of establishing a traction control redundant network of the present invention further includes: in response to the train-level backbone network returning to normal, switching the train-level backbone network as a traction control network.

[0008] In one or more embodiments, a method of establishing a traction control redundant network of the present invention further includes: configuring the Ethernet as a main communication network for devices between carriages when the train-level backbone network is normal.

[0009] In one or more embodiments, a method for forming a traction control redundant network of the present invention also includes: in response to a breakpoint occurring in the Ethernet, configuring the car equipment on one side of the breakpoint to send equipment data to a first switch at the head or tail of the vehicle, and the first switch at the head or tail of the vehicle sends the equipment data to a corresponding second switch in the train-level backbone network so that the train-level backbone network can communicate with the car equipment on the other side of the breakpoint.

[0010] In one or more embodiments, a method of establishing a traction control redundant network of the present invention also includes: configuring a first timeout threshold for the Ethernet; determining that the Ethernet fails in response to the train central control unit not receiving the first heartbeat information within the time corresponding to the first timeout threshold.

[0011] In one or more embodiments, a method of forming a redundant traction control network of the present invention further includes: when the Ethernet fails and the train-level backbone network has not been restored, configuring a pre-configured hard line in the vehicle as a backup emergency traction control network for use.

[0012] In one or more embodiments, a method of forming a traction control redundant network of the present invention further includes: configuring a manual switching button for the Ethernet to manually switch the Ethernet as a backup emergency traction control network for use when a failure occurs in the train-level backbone network.

[0013] In one or more embodiments, the manual switch button includes a hardware switch button and / or a software switch button, wherein the software switch button is installed in the operating system of the central control unit.

[0014] The beneficial effects of the present invention include: the present invention can increase the redundancy of the network on the basis of the existing communication network of the EMU to achieve network upgrade, and can avoid the disadvantage that the central control unit of the existing EMU in the emergency traction mode cannot obtain and display key monitoring information such as the traction torque of the slave power car through the hard-wired network, thereby greatly improving the reliability and safety of the EMU operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A flowchart of a method for establishing a traction control redundant network according to an embodiment of the present invention; Figure 2 A schematic diagram of a network topology structure of a train constructed by the method of the present invention according to an embodiment of the present invention; Figure 3 A schematic diagram of a data flow scheduling process of a network topology structure constructed based on the present invention; Figure 4 A timing diagram of hot standby switching between an Ethernet network and a train-level backbone network in a network topology structure constructed based on the present invention; Figure 5 The figure is a logical diagram of emergency traction control of a network topology structure constructed based on the present invention. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0018] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0019] In order to improve the safety and reliability of traction control based on the existing EMU and reduce the cost of the transformation as much as possible, in one embodiment, the present invention proposes a method for establishing a traction control redundant network, such as Figure 1 As shown, the method includes: step S1, cascading the local area networks in adjacent carriages through the first switch and the second switch preset in each carriage to form a two-way communication Ethernet, and making the first switch in the head and tail carriages of the train communicate with the second switch to form a ring network; step S2, respectively arranging gateways in the head and tail carriages of the train so that the gateways forward data between the train central control unit and various devices in the middle carriages; step S3, respectively connecting the first switch and the second switch in the head and tail carriages of the train with the third switch and the fourth switch in the original train-level backbone network of the vehicle one by one to form a redundant communication network; and step S4, respectively connecting the first switch and the second switch in the head and tail carriages of the train with the train central control unit in the head and tail carriages.

[0020] Specifically, this embodiment proposes to form an Ethernet that runs through the train and can achieve two-way communication by cascading the local area network in each carriage of the EMU (train) through two switches preset in the local area network in each carriage, and configure the Ethernet to have a higher priority than the hard line so that it can be used as the first backup traction control communication network to be activated when the original train-level backbone network of the train fails. Compared with the traction control performed by hard lines, the Ethernet in this embodiment can achieve more precise control and ensure the normal transmission of various monitoring data of the train, thereby greatly improving the safety and reliability of the train traction control.

[0021] For more details, see Figure 2, which shows the network topology of the train constructed by the method of the present invention, wherein the power car and the control car are the first and last cars of the train respectively, and the vehicles located between the first and last cars can be ordinary trailers, dining cars and Boeing cars. The central control unit (CCU) is respectively arranged in the power car and the control car, and adopts a master-slave control mode, that is, only one central control unit works at any time, and the other is in hot standby state; the train-level backbone network (ETB) is composed of switches ETB-A, ETB-B and multiple ETB repeaters (for signal amplification), wherein ETB-A and ETB-B are mutually hot standby redundant and are respectively connected to the central control unit for communication. The Ethernet formed by the present invention is composed of multiple switches ECN-A and ECN-B, wherein ECN-A and ECN-B are switches in the original local area network in the train compartment. The present invention cascades the local area networks between adjacent compartments through ECN-A and ECN-A to form a two-way communication Ethernet, and interconnects the ECN-A and ECN-B in the head and tail compartments of the train to form a ring network (no ring network is formed in the middle compartment), so that the Ethernet forms a train-level ring network for redundant communication, and by connecting ECN-A to ETB-A and connecting ECN-B to ETB-B, a redundant communication connection between the Ethernet ring network and the train-level backbone network is further formed, and the two are mutually redundant communication networks. In addition, since the original local area network in the compartment uses a two-layer switch, it does not support the TTDP topology discovery protocol, that is, it is impossible to identify devices with the same IP address in different compartments. For this reason, it is necessary to set a gateway between the central control unit of the head and tail compartments of the train and the first switch communication, so that the gateway can reallocate the IP address to the device according to the compartment where the device is located.

[0022] In one embodiment, a method for establishing a traction control redundant network of the present invention further includes: configuring Ethernet according to the data format, packet sending rate and packet sending period in the train-level backbone network.

[0023] Specifically, the ETB network and the ECN network have a bandwidth of 100M, which can transmit data information for traction control and status display between the power car and the control car. At the same time, in order to ensure that the ETB network can be switched to the ECN network in hot standby when the ETB network fails, the data format, packet rate and packet cycle configuration of the transmitted information on the ETB and ECN networks need to be exactly the same to ensure one-to-one mapping and synchronous switching of the dual-network data.

[0024] Secondly, in order to ensure the hot standby switching between the ETB network and the cascaded ECN network, the present invention also formulates a data flow redundancy scheduling strategy, see Figure 3, the data flow scheduling process includes: on the ETB side ①, the master and slave control section power car / control car respectively send their own control and status information to the opposite power car / control car. On the ECN side ②, the master and slave control section power car / control car respectively send their own control and status information to the Ethernet gateway of this section, and the Ethernet gateway receives the data sent by the CCU of this section and forwards it to the Ethernet gateway of the opposite side. After receiving the data, the Ethernet gateway of the opposite side forwards it to the CCU of this section. The above process is the data synchronization process of the master and slave central control units; in addition, the CCU of each power car / control car also monitors the heartbeat signal sent by the opposite ETB switch and Ethernet gateway in real time. When the ETB network is disconnected or the communication is interrupted due to equipment failure, the data in the buffer area remains unchanged, and the receiving port in the central control unit is switched to the ECN network for real-time transmission and reception. After that, when the CCU detects that the heartbeat information in the ETB network is restored and maintained for more than the preset time, the data in the buffer area remains unchanged, and the receiving port is switched back to the ETB network for real-time transmission and reception.

[0025] In an optional embodiment, during the data synchronization process between the master and slave central control units, the CCU preferentially receives the synchronization data transmitted in the current master communication network and discards the synchronization data transmitted by the backup control network.

[0026] In an optional embodiment, during the data synchronization process between the master and slave central control units, the synchronization data is only transmitted by the backup communication network, and the master communication network mainly transmits traction control signals and various equipment monitoring signals.

[0027] Specifically, the traction control signals and various equipment monitoring signals transmitted by the main communication network are shown in Table 1 and Table 2 below, wherein Table 1 shows the main traction control signals and Table 2 shows the main status monitoring signals: Table 1: Traction control signal table Serial number Signal name Control function description Scope of application Emergency Tow Mode Activated The emergency traction activation switch is set on the display screen in the driver's cab, including: input position, cut-off position; the activation signal of the emergency traction mode runs through the entire train through the trailer Ethernet; the signal is not passed during short-term reconnection and the electric key activation signal needs to be interlocked. The emergency traction mode can only be activated when the electric key is activated. After the emergency traction mode is activated, disconnect the electric key and the mode remains Power car / control car Driver's cab occupancy conflict This signal indicates that two driver's cabs are occupied at the same time; the occupancy status of the driver's cabs is transmitted through the trailer control network, and the microcomputer system makes a comprehensive judgment. When two keys are activated, it indicates an occupancy conflict and the main switch should be disconnected, the pantograph should be lowered, and the penalty brake should be applied. Power car / control car Direction forward The master car sends a valid Power car / control car Directionally neutral The master car sends a valid Power car / control car Direction backward The master car sends a valid Power car / control car Pantograph raising command The master car sends a valid pulse (3s pulse is valid) Power car / control car Pantograph lowering command The master car sends a valid Power car / control car Main breaker closing command The master car sends a valid pulse (3s pulse is valid) Power car / control car Main disconnect command The master car sends a valid Power car / control car Air compression command The master car sends a valid Power car / control car Air compressor instructions The master car sends a valid Power car / control car Air compressor power pump instruction The master car sends a valid Power car / control car Air pressure requirements for multiple-unit vehicles (680kpa, 750kpa) Each car sends effective Power car / control car Driver controller traction command The master car sends a valid Power car / control car Braking command from driver controller The master car sends a valid Power car / control car Controller neutral command The master car sends a valid Power car / control car Controller level percentage The signal is transmitted through the trailer control network and received by the control power vehicle to realize the calculation and display of the set speed in speed mode. Power car / control car Set torque percentage The signal is transmitted through the trailer control network and received by the control power vehicle to achieve precise torque control in speed mode and torque mode. Power car / control car Air-electric combined application state Air-electric combined application status fed back by each power car Power car / control car Air-electric combined isolation Air-electricity joint conditions are not met Power car / control car Full train traction blockade Each car is sent according to its status to control the blocking of the entire train Power car / control car Full train electrical lockout Each car is sent according to its status to control the blocking of the entire train Power car / control car Penalty brake command Emergency brake command Key signal Each car is sent according to its status Power car / control car Table 2: Status display signal table Serial number Display signal description Scope of application Network pressure Power car / control car Primary current Power car / control car Traction / braking force Power car / control car Set speed, set force, traction mode Power car / control car Column supply voltage and current Power car / control car Control voltage and current Power car / control car Direction Status Power car / control car Pantograph status Power car / control car Main disconnect status Power car / control car Traction and brake settings Power car / control car Idle state Power car / control car Sanding status Power car / control car Air-electric joint status Power car / control car Phase state Power car / control car Normal braking state Power car / control car Parking brake status Power car / control car Emergency braking state Power car / control car No alert status Power car / control car Fault information (Class A) Power car / control car Tips Power car / control car Operating conditions (4) Power car / control car This supplement status Power car / control car Flow value Power car / control car Balanced air cylinder pressure value Power car / control car Train pipe pressure value Power car / control car Total wind pressure value Power car / control car Brake pressure value Power car / control car Trailer brake status Power car / control car Working Mode Power car / control car Train braking force value Power car / control car Tail car pressure (train pipe, brake cylinder, total air) Power car / control car Vehicle information Power car / control car Trailer Information Power car / control car In an optional embodiment, during the data synchronization process between the master and slave central control units, the CCU simultaneously receives the synchronization data transmitted by the master control network and the backup control network and compares them to determine whether the synchronization data is complete. If complete, the identical data is discarded; if incomplete, the difference data is stored in the designated area of ​​the data storage module and an alarm is issued.

[0028] In one embodiment, the method of the present invention also includes: configuring the central slave control unit to send a first heartbeat message to the central master control unit through a gateway and multiple first switches, and configuring Ethernet as a backup emergency traction control network to be put into use when a train-level backbone network fails.

[0029] Specifically, a first timeout threshold is configured for Ethernet; in response to the train central control unit not receiving the first heartbeat information within the time corresponding to the first timeout threshold, an Ethernet failure is determined; at the same time, in the ETB network, the central slave control unit sends a second heartbeat information to the central master control unit through multiple second switches, and if the second heartbeat information is not received within the time corresponding to the preset second timeout threshold, it is determined that the train-level backbone network has a failure, and the Ethernet automatically switches to take over the work of the train-level backbone network. If the second heartbeat information in the train-level backbone network returns to normal, it automatically switches to the train-level backbone network for communication.

[0030] See also Figure 4 , which shows the timing diagram of the hot standby switching between Ethernet and train-level backbone network of the present invention. Among them, T1 is the time corresponding to the first timeout threshold and the second timeout threshold, and T2 is the conversion time required for the switching between Ethernet and train-level backbone network, that is, it is necessary to maintain T2 time to determine whether the network to be switched is working normally. Optionally, the size of T2 is 3-5 heartbeat cycles.

[0031] In one embodiment, the method of the present invention further comprises: configuring Ethernet as the main communication network for devices between carriages when the train-level backbone network is normal.

[0032] Specifically, this embodiment uses Ethernet as a backup traction control network and as the main network for equipment communication between carriages to reduce the burden on the main traction control network (i.e., the main communication network) and reduce the number of messages sent in the main traction control network, thereby improving the safety and reliability of traction control.

[0033] In one embodiment, the method of the present invention further includes: in response to a breakpoint in the Ethernet, configuring the carriage device on one side of the breakpoint to send device data to the first switch at the head or tail of the vehicle, and the first switch at the head or tail of the vehicle sends the device data to the corresponding second switch in the train-level backbone network so that the train-level backbone network can communicate with the carriage device on the other side of the breakpoint. Specifically, since the switches of the Ethernet and the train-level backbone network are interconnected, this embodiment proposes that when a breakpoint failure occurs in the Ethernet, the train-level backbone network can bypass the breakpoint to communicate between the carriage devices.

[0034] In one embodiment, the method of the present invention further comprises: when the Ethernet fails and the train-level backbone network has not been restored, configuring the pre-configured hard wire in the train to be used as a backup emergency traction control network.

[0035] Specifically, this embodiment needs to allocate switching priorities to the constructed Ethernet and hard-wired network of the present invention respectively, and configure the constructed Ethernet of the present invention to have a higher automatic switching priority than the hard-wired network after a train-level backbone network failure.

[0036] In one embodiment, the method of the present invention further includes: configuring a manual switching button for Ethernet, which is used to manually switch Ethernet as a backup emergency traction control network to be put into use when a train-level backbone network fails. The manual switching button includes a hardware switching button and / or a software switching button, wherein the software switching button is installed in the operating system of the central control unit.

[0037] Specifically, in order to ensure the senseless switching and reliable use of the emergency traction function of the EMU, the present invention designs an emergency traction control method as follows: Figure 5 As shown, the control method includes: under normal operating conditions, the driver does not need to manually set the emergency traction mode. The control system monitors the communication status of the ETB and ECN networks in real time according to the redundant switching strategy. When it is found that the ETB network data frame loss exceeds T1 time, it automatically switches to the ECN network, switches to the emergency traction mode, and displays it on the display screen. The relevant control state remains unchanged, and the traction mode such as speed mode and torque mode can continue to be used for train control. At the same time, in order to ensure that this function can be manually set and activated, an emergency traction mode conversion hardware switch is set on the control panel, or an emergency traction mode conversion soft switch is set on the display screen. The central main control unit of the train recognizes the switch switching signal and controls the entire train of power / control cars to enter the emergency traction mode. When the emergency traction mode is activated, the necessary main control car control signals such as the pantograph, main circuit breaker, traction, etc. are forwarded through the ECN network via the Ethernet gateway and transmitted to the power cars / control cars of the entire train. The central main control unit of the train recognizes the signal to realize the high voltage, traction and electric braking actions in the emergency traction mode.

[0038] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope of the embodiments disclosed in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order.

[0039] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A method for establishing a traction control redundant network, characterized in that: The method comprises: The local area networks in adjacent carriages are cascaded through the first and second switches preset in each carriage to form a two-way communication Ethernet, and the first switches in the head and tail carriages of the train are connected to the second switches to form a ring network; Gateways are respectively arranged in the front and rear carriages of the train so that the gateways can forward data between the central control unit of the train and the devices in the middle carriages; The first switch and the second switch in the front and rear carriages of the train are respectively connected to the third switch and the fourth switch in the original train-level backbone network of the vehicle in a one-to-one correspondence to form a redundant communication network; The first switch and the second switch in the head and tail carriages of the train are respectively connected to the train central control unit in the head and tail carriages of the train for communication.

2. A method for establishing a traction control redundant network according to claim 1, characterized in that: The method further comprises: The Ethernet is configured according to the data format, packet sending rate and packet sending period in the train-level backbone network.

3. A method for establishing a traction control redundant network according to claim 2, characterized in that: The method further comprises: The central slave control unit is configured to send the first heartbeat information to the central master control unit through the gateway and the first switches, and the Ethernet is configured as a backup emergency traction control network to be used when the train-level backbone network fails.

4. The method for establishing a traction control redundant network according to claim 3, characterized in that: The method further comprises: In response to the train-level backbone network returning to normal, the train-level backbone network is switched as a traction control network.

5. The method for establishing a traction control redundant network according to claim 3, characterized in that: The method further comprises: The Ethernet is configured as the main communication network for devices between carriages when the train-level backbone network is normal.

6. A method for establishing a traction control redundant network according to claim 5, characterized in that: The method further comprises: In response to a breakpoint occurring in the Ethernet network, the car equipment on one side of the breakpoint is configured to send device data to the first switch at the head or tail of the vehicle, and the first switch at the head or tail of the vehicle sends the device data to the corresponding second switch in the train-level backbone network so that the train-level backbone network can communicate with the car equipment on the other side of the breakpoint.

7. The method for establishing a traction control redundant network according to claim 3, characterized in that: The method further comprises: Configuring a first timeout threshold for the Ethernet network; The Ethernet failure is determined in response to the train central control unit not receiving the first heartbeat information within the time corresponding to the first timeout threshold.

8. The method for establishing a traction control redundant network according to claim 7, characterized in that: The method further comprises: When the Ethernet fails and the train-level backbone network is not restored, the pre-configured hard line in the configuration vehicle is put into use as a backup emergency traction control network.

9. The method for establishing a traction control redundant network according to claim 1, characterized in that: The method further comprises: A manual switching button is configured for the Ethernet to manually switch the Ethernet to be used as a backup emergency traction control network when a failure occurs in the train-level backbone network.

10. The method for establishing a traction control redundant network according to claim 9, characterized in that: The manual switch button includes a hardware switch button and / or a software switch button, wherein the software switch button is installed in the operating system of the central control unit.

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