Remote automatic switching test method and system for double-machine hot backup of a train control center

Abstract

This application discloses a remote automatic system switching test method and system for dual-machine hot standby in a train control center. The main technical solution of this application is as follows: The test control terminal issues a first control command based on a target script, which instructs the forced switching of the first system to the master control system. The target script pre-writes the execution logic for normal system switching testing of the TCC and the corresponding first expected feedback result. In the TCC dual-machine hot standby architecture, the first system and the second system are redundant backups of each other, and their master control states are mutually exclusive. After receiving the first control command and completing the interlock check, the PLC controls the relay contacts corresponding to the first system to close. In pure remote mode, power supply is connected to the first signal channel of the TCC through the closed relay contacts; after the TCC acquires a high-level signal, it executes the operation of switching the first system to the master control system. The test control terminal verifies whether the TCC system switching action is successful based on the first expected feedback result in the target script.

Description

Technical Field

[0001] This application relates to the field of automated testing technology for dual-machine hot standby systems in train control centers, and in particular to a remote automatic switching test method and system for dual-machine hot standby systems in train control centers. Background Technology

[0002] In high-speed railway and urban rail transit communication and signaling systems, the Train Control Center (TCC) is the core ground equipment. To ensure high reliability and high safety, a dual-machine hot standby redundancy architecture is usually adopted, which includes an A-series main controller, a B-series main controller, and automatic shutdown logic.

[0003] Currently, to achieve intervention-based shutdown (i.e., forced switching between primary and backup systems), existing designs typically install an industrial-grade three-position self-locking rotary switch on the cabinet surface. This switch has three physical positions: left position (position 1), corresponding to A-system master control commands; middle position (position 0), corresponding to automatic mode; and right position (position 2), corresponding to B-system master control commands. Electrically, this switch connects to the digital input (DI) port of the TCC safety acquisition board. Through the opening and closing of internal contacts, a high-level signal (such as DC 24V) is input to the designated acquisition channel of the TCC. The TCC's internal software determines the current control mode based on the acquired high and low level combinations, i.e., A-system master control, B-system master control, or automatic shutdown.

[0004] Therefore, when testers need to verify the "system switching" action of TCC dual-machine hot standby (including switching to the A-series master controller, the B-series master controller, and verifying the automatic failover logic), they must go to the cabinet, manually operate the industrial-grade three-position self-locking rotary switch, and manually observe the system's operating status and feedback results. Since system switching testing heavily relies on such physical rotary switch operations, and existing automated testing solutions mainly focus on the software logic and communication protocol layers, failing to cover the physical control aspects of master-slave switching, test cases involving TCC dual-machine hot standby master-slave switching cannot achieve full-process automation. This significantly restricts testing efficiency and security, and is a technical problem that urgently needs to be solved. Summary of the Invention

[0005] This application provides a remote automatic switching test method and system for dual-machine hot standby in train control centers. The main purpose is to completely bypass the physical operation of manual knobs by using a PLC to replace traditional mechanical switches, and to build a complete closed loop of "initiating switching command → PLC outputting level signal → TCC executing switching → remotely verifying switching results". This achieves remote automation of the entire switching test process, effectively improving test efficiency and safety, and providing an efficient and reliable automated solution for TCC dual-machine hot standby master-slave switching test.

[0006] To achieve the above objectives, this application mainly provides the following technical solutions: The first aspect of this application provides a remote automatic system switching test method for dual-machine hot standby in a train control center, the method comprising: The test control terminal sends a first control instruction to the PLC based on the target script. The first control instruction is used to instruct the first system to be switched to the master control system. The target script is pre-written with the execution logic of the TCC normal system switching test and its corresponding first expected feedback result. In the TCC dual-machine hot standby architecture, the first system and the second system are redundant backups of each other and their master control states are mutually exclusive. After receiving the first control command and performing an interlock check, the PLC controls the corresponding relay contact of the first system to close. In remote mode, the power supply is connected to the first signal channel of the TCC through the relay contact corresponding to the first system that has been activated, and after the TCC acquires a high-level signal, the TCC performs the operation of switching the first system to the main control system. The test control terminal verifies whether the TCC switching action is successful based on the first expected feedback result in the target script.

[0007] The second aspect of this application provides a remote automatic switching test system for dual-machine hot standby in a train control center, which is applied to the remote automatic switching test method for dual-machine hot standby in a train control center as described above. The system includes at least: a test control terminal, a PLC, and a TCC.

[0008] A third aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the remote automatic system switching test method described above for dual-machine hot standby in a train control center.

[0009] A fourth aspect of this application provides an electronic device, the device including at least one processor, and at least one memory and bus connected to the processor; The processor and the memory communicate with each other via the bus. The processor is used to call program instructions in the memory to execute the remote automatic system switching test method for dual-machine hot standby in the train control center as described above.

[0010] By employing the above-described technical solution, the technical solution provided in this application has at least the following advantages: This application provides a remote automatic system switching test method and system for dual-machine hot standby in a train control center. The test control terminal issues a first control command based on a target script, which instructs the forced switching of the first system to the master control system. The target script pre-writes the execution logic of the normal system switching test of the TCC and the corresponding first expected feedback result. In the TCC dual-machine hot standby architecture, the first system and the second system are redundant backups of each other, and their master control states are mutually exclusive. After receiving the first control command and completing the interlock check, the PLC controls the relay contacts corresponding to the first system to close. In pure remote mode, power supply is connected to the first signal channel of the TCC through the closed relay contacts; after the TCC acquires a high-level signal, it executes the operation of switching the first system to the master control system. The test control terminal verifies whether the TCC system switching action is successful based on the first expected feedback result in the target script.

[0011] Compared to TCC switching tests that rely on traditional mechanical switches to initiate commands, which makes it difficult to remotely and fully automate the testing process, this method uses a PLC to replace traditional mechanical switches. This completely bypasses the physical operation of manual knobs and establishes a complete closed loop: "initiating switching command → PLC outputting level signal → TCC executing switching → remotely verifying switching results." This achieves remote automation of the entire switching test process, effectively improving testing efficiency and safety, and providing an efficient and reliable automated solution for TCC dual-machine hot standby master-slave switching tests.

[0012] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0013] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 A schematic diagram of the overall architecture of a remote automatic switching test system for dual-machine hot standby in a train control center, provided for an embodiment of this application; Figure 2 A schematic diagram of the overall architecture of another remote automatic switching test system for dual-machine hot standby in train control center provided in this application embodiment; Figure 3 Example 1 provided for the embodiments of this application: Architecture diagram; Figure 4Example 2 provided for embodiments of this application: Electrical connection topology diagram; Figure 5 Example 3 provided for the embodiments of this application: PLC wiring diagram; Figure 6 A flowchart of a remote automatic system switching test method for dual-machine hot standby in a train control center, provided in an embodiment of this application; Figure 7 A flowchart of another remote automatic system switching test method for dual-machine hot standby in train control center provided in this application embodiment. Detailed Implementation

[0014] Exemplary embodiments of the present application will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this application will be thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0015] Currently, to achieve intervention-based shutdown (i.e., forced switching between primary and backup systems), existing designs typically install an industrial-grade three-position self-locking rotary switch on the cabinet panel. This mechanical switch has three physical positions: left position (position 1), corresponding to A-system master control commands; middle position (position 0), corresponding to automatic mode; and right position (position 2), corresponding to B-system master control commands. Electrically, this switch connects to the digital input (DI) port of the TCC safety acquisition board. Through the on / off state of its internal contacts, a DC 24V high-level signal is input to the designated acquisition channel of the TCC. The TCC's internal software determines the current control mode—A-system master control, B-system master control, or automatic shutdown—based on the acquired high / low level combination.

[0016] When testers need to verify the "system switching" action of the TCC dual-machine hot standby, they must go to the cabinet and manually rotate the mechanical switch mentioned above to change the on / off state of the internal contacts, thereby sending a high-level command to the TCC. This mechanical switch has no electronic control interface and cannot be directly triggered by software or network commands, which is a typical pure manual physical operation.

[0017] The complete switchover test loop can be seen as follows: initiate switchover command → TCC executes switchover → verify switchover results. Since the "initiate switchover command" step relies on the manual knob "mechanical switch" mentioned above, if the entire switchover test process is to be automated, the operation of this manual knob "mechanical switch" is an unavoidable breakpoint in the automated test loop, which directly leads to the inability to achieve unattended automated execution of test cases related to master / slave switchover.

[0018] Based on the above considerations, this application provides a remote automatic system switching test system for dual-machine hot standby in a train control center. The overall architecture of the test system is as follows: Figure 1 As shown, the system comprises a test control terminal (host computer) 11, a programmable logic controller (PLC) 12, and a device under test (TCC) 13. In the overall architecture of this test system, the test control terminal and the PLC are connected via an Ethernet network, using industrial Ethernet protocols such as Modbus TCP or S7 to achieve bidirectional instruction and status data interaction. The PLC and the TCC are connected via digital signals. The PLC sends power (e.g., DC 24V) level signals to the digital input (DI) port of the TCC's safety acquisition board through its own relay output contacts (e.g., Q0.0, Q0.1).

[0019] Specifically, the test control terminal provides a Python-based automated script or HMI (Human-Machine Interface) for data interaction with the PLC via Ethernet protocol, serving as the system's human-machine interface and decision-making layer. The core functions of the test control terminal include: issuing test commands such as system switching and fault injection to the PLC; reading status feedback from the PLC and TCC; and automatically verifying and logging test results, thereby achieving an unattended automated testing closed loop.

[0020] Specifically, the PLC receives commands from the test control terminal, runs its internal logic program (interlocking, delay, fault injection, etc.), controls the opening and closing of the output relay contacts, and converts digital commands into physical level signals. The core functions of the PLC include: acting as the instruction execution layer, converting host computer commands into DI level signals recognizable by the TCC; implementing interlocking protection for A / B series switching signals to prevent short circuits or conflicts; simulating mechanical switch characteristics to provide precise timing control for testing the TCC's debouncing and fault detection logic.

[0021] Specifically, the TCC detects the high and low level combinations from the PLC through the DI port of the safety acquisition board, determines the control mode based on its internal safety logic, and executes master / standby system switching or fault alarm. The core functions of the TCC include: receiving system switching control signals as the tested object; executing master / standby system switching logic and feeding back the current master control status and system log; providing verification basis for the test control terminal, and completing the closed loop of system switching test.

[0022] like Figure 1 The overall architecture of the test system shown features a hardware improvement that replaces traditional mechanical switches with PLCs. Based on this design improvement, this application also provides another remote automatic switching test system for dual-machine hot standby in train control centers, such as... Figure 2As shown, in addition to the test control terminal (host computer) 11, programmable logic controller (PLC) 12 and device under test (TCC) 13, the overall architecture of the test system also includes a mode switching module (local / remote selection switch) 14. It should be noted that the mode switching module 14 is essentially a hardware entity. Its core design is the local / remote selection switch, and the electrical connection and mutual isolation between the local control path and the remote control path are realized through the switching of the switch position.

[0023] Below, on Figure 2 The overall architecture of the remote automatic switching test system for dual-machine hot standby in the train control center is explained.

[0024] like Figure 2 In the overall architecture of this testing system, the test control terminal and the PLC are connected via an Ethernet network. Bidirectional command and status data interaction is achieved through industrial Ethernet protocols such as Modbus TCP or S7. The PLC and the mode switching module are connected via digital signals, serving as a remote control path. The PLC sends a power supply (e.g., DC 24V) level signal to the mode switching module through relay output contacts. Furthermore, the existing mechanical switch also establishes a digital signal connection with the mode switching module, serving as a local control path. Thus, the mode switching module can provide either a remote control path or a local path depending on its position. The mode switching module and the TCC are connected via digital signals. The mode switching module uses either the remote control path or the local control path to forward control signals from the PLC or mechanical switch to the digital input (DI) port of the TCC's safety acquisition board.

[0025] Specifically, the core tasks of the test control terminal are... Figure 1 The core functionalities of the test control unit in the overall architecture are the same, and will not be elaborated upon here. PLC and Figure 1 The core functions of the PLC in the overall architecture are basically the same: converting test commands into level signals. The difference lies in that its output is only connected to the mode switching module and does not directly drive the TCC. Furthermore, the TCC only receives the final control signal from the mode switching module, executes the switching logic, and provides status feedback.

[0026] Specifically, the mode switching module can be a manual double-pole double-throw (DPDT) physical switch or a similar mode switching switch. Through position switching, it electrically selects between the PLC's "remote control path" and the original mechanical knob's "local control path," while physically isolating the two paths. The core functions of the mode switching module include the following: (1) Mode selection: When switched to the "remote" position, only the PLC signal is forwarded to realize automated testing; when switched to the "local" position, only the mechanical switch knob signal is forwarded to restore manual operation.

[0027] (2) Security isolation: Physically disconnect unselected paths to avoid interference between remote and local signals, thereby improving system security and fault isolation capabilities.

[0028] Based on (1) and (2) above, this embodiment of the application achieves a smooth switch between remote testing and local operation and maintenance without modifying the original input logic of TCC. Figure 2 The overall architecture of the test system shown in this application embodiment provides a "PLC in parallel with traditional mechanical switches" method, which realizes remote automated control of TCC switching system testing through "remote + local" dual modes.

[0029] To demonstrate more clearly Figure 2 The overall architecture diagram of the test system is shown in Example 1 of this application: Architecture Diagram (e.g.) Figure 3 As shown in the figure, Example 1 is a typical engineering implementation of the "PLC in parallel with traditional mechanical switch" method. It constructs a "remote + local" dual-mode compatible TCC switching system test system, including a remote test link and a local operation and maintenance link.

[0030] The remote testing link is as follows: The test control terminal (running a Python script or HMI human-machine interface) sends control commands to the S7-1200 PLC via Ethernet. The PLC converts the software commands into DC 24V level signals at the relay output points Q0.0 / Q0.1, which are then connected to the DI_A / DI_B ports of the TCC via the "local / remote switch" to achieve unattended normal switching or fault injection testing.

[0031] The local operation and maintenance link is as follows: the original mechanical knob switch is connected to the same changeover switch. When switching to the local position, the original manual operation process can be fully reused to ensure on-site operation and maintenance and emergency operation.

[0032] In Example 1, electrical isolation and selection between two control paths are achieved through physical switches. Without altering the original TCC logic, this approach retains the safety redundancy of manual operation while also achieving high efficiency in remote automated testing. It represents a complete implementation of the testing process using the "PLC in parallel with traditional mechanical switches" method.

[0033] Furthermore, to more clearly illustrate the electrical connections in the architecture of Example 1, this application embodiment also provides Example 2: an electrical connection topology diagram (such as...). Figure 4As shown in the figure, Example 2 is the electrical connection topology implementation of the "PLC in parallel with traditional mechanical switch" method in the test process. The core is to achieve physical isolation and switching of the two control paths of "local manual control + remote PLC control" at the electrical level by switching the switch in double-pole double-throw mode.

[0034] In Example 2, the core hardware is a DC 24V powered local / remote switching switch (double-pole double-throw (DPDT) physical switch), which serves as the electrical selector for the entire system. Example 2 provides path divisions including local mode (position 1) and remote mode (position 2).

[0035] Local mode (position 1): Connect the DC 24V power supply to the original mechanical knob, and then selectively conduct the power to the TCC's DI channel 1 (forced A series) or DI channel 2 (forced B series) by the knob contacts, completely reusing the existing manual operation logic; Remote mode (position 2): Connect the DC 24V power supply to the common output terminal 1L of the PLC. The PLC controls the Q0.0 (analog switch A) and Q0.1 (analog switch B) relay contacts to close, outputting a high level to the corresponding DI channel of the TCC.

[0036] The safety features implemented based on the local mode (gear 1) and remote mode (gear 2) are as follows: physical gears are mutually exclusive, ensuring electrical isolation between the local and remote control paths, and avoiding signal conflicts or false triggering.

[0037] Specifically, the remote control logic implemented in remote mode (gear 2) is an automated switching system driven by the PLC. The provided signal mapping is as follows: PLC Q0.0 is activated → TCC DI channel 1 is turned on → forced switching to system A; PLC Q0.1 is activated → TCC DI channel 2 is turned on → forced switching to system B; both Q0.0 and Q0.1 are deactivated → TCC recognizes it as automatic mode.

[0038] During normal switching, the PLC first disconnects the current contact, delays to simulate a mechanical dead zone, and then closes the target contact to prevent signal conflicts. During fault injection, the interlock can be temporarily released, allowing Q0.0 and Q0.1 to close simultaneously, simulating a switch short circuit / illegal state, and verifying the TCC fault-tolerant protection logic.

[0039] Specifically, the local control logic implemented in local mode (gear 1) retains the original manual operation and maintenance. When switching to local gear, the TCC switching input (DI) is directly connected to the original mechanical knob, which is completely consistent with the operation before the modification. This allows on-site personnel to perform normal switching or emergency operations, ensuring system safety redundancy.

[0040] In Example 2, a "local / remote" electrical isolation is achieved through a double-pole double-throw switch. In local mode, the original mechanical knob is reused, while in remote mode, the TCC DI channel is driven by a PLC (Q0.0 / Q0.1). This completes the electrical topology and control logic for "remote + local" dual-mode TCC switching system testing.

[0041] Furthermore, to more clearly illustrate the PLC wiring in the architecture of Example 1, this application embodiment also provides Example 3: PLC wiring diagram (e.g. Figure 5 (As shown). Example 3 is the hardware wiring implementation of the "PLC in parallel with traditional mechanical switch" method in the test process. It completes the physical connection of the three types of circuits, namely power supply, signal and communication, through a double-pole double-throw switch, realizing the electrical implementation of "local / remote" dual-mode control.

[0042] In Example 3, the core connection is: the positive terminal of the DC 24V+ power supply provided inside the TCC is connected to the common terminal (COM) of the double-pole double-throw switch, which serves as the sole power source for the entire switching control signal. This ensures that the local and remote control paths share the same power supply and that the signal level characteristics are consistent, thus avoiding misjudgment by the TCC due to power supply differences.

[0043] Furthermore, the signal loop provided in Example 3 offers electrical isolation for both local and remote operation. In local mode, when the switch is set to "Local (L)", DC 24V+ is connected to the input terminal of the original control knob. The knob outputs A / B position signals, which are connected to Pin A (DI_A channel) and Pin B (DI_B channel) on the TCC backplane, respectively, fully reusing the original manual control logic.

[0044] In remote mode: When the switch is set to "Remote Terminal (R)," DC 24V + is connected to the PLC's common output terminal 1L. The PLC's internal relays control the on / off state of contacts Q0.0 and Q0.1. Specifically: Q0.0 is energized → outputs a high level to TCC Pin A (DI_A), forcing a switch to the A series; Q0.1 is energized → outputs a high level to TCC Pin B (DI_B), forcing a switch to the B series; both Q0.0 and Q0.1 are de-energized → TCC recognizes it as automatic mode. The double-pole double-throw switch physically isolates the local / remote paths, avoiding signal conflicts and ensuring electrical safety.

[0045] Example 3 provides a communication loop for remote command channels. Its core connection is as follows: the PLC connects to the test laboratory's local area network via an RJ45 network cable, establishing Ethernet communication (such as Modbus TCP / S7 protocol) with the test control terminal. This enables the issuance of test commands and the exchange of status feedback data, forming the communication foundation for remote automated testing.

[0046] Combining the above Figure 1 and Figure 2 To summarize the explanations and descriptions in this application's embodiments, such as... Figure 1 The diagram shows a purely remote architecture. Commands are issued from the test control terminal, transmitted to the PLC via a communication link, and the PLC converts the commands into electrical signals to directly drive the TCC. This achieves automated system switching without relying on local manual operation (i.e., manual operation of knobs or mechanical switches), and there is no local backup operation mode. Furthermore, as... Figure 2 It is shown as a dual-mode architecture, in Figure 1 Based on the pure remote architecture, a mode switching module has been added. Through the mode switching module, it is possible to switch between two modes: remote automated testing and local manual operation and maintenance. It supports both remote automated system switching testing and retains the ability to operate manually on site, which is more in line with actual engineering application scenarios.

[0047] Furthermore, in order to Figure 1 The overall structure and workflow of the test system shown are explained. This application provides a remote automatic switching test method for dual-machine hot standby in a train control center, such as... Figure 6 As shown, this method achieves remote automated testing of the TCC switching system by "replacing traditional mechanical switches with PLC". The specific implementation steps of this application embodiment are as follows: Step 101: The test control terminal sends a first control instruction to the PLC based on the target script. The first control instruction is used to instruct the first system to be switched to the master control system. The target script is pre-written with the execution logic of the TCC normal system switching test and its corresponding first expected feedback result. In the TCC dual-machine hot standby architecture, the first system and the second system are redundant backups of each other and their master control states are mutually exclusive.

[0048] It should be noted that in this embodiment, "first system" and "second system" refer to the A system and B system in the TCC dual-machine hot standby architecture, and there is no fixed correspondence between them (i.e., it does not specifically mean that "first system" is A system or "second system" is B system). This expression is used to emphasize that the TCC system switching operation is performed between the two systems. In addition, when describing the control commands corresponding to different test scenarios (such as normal system switching test or fault injection test), for ease of distinction, this embodiment uses "first" and "second" as identification prefixes: "first control command" corresponds to "normal system switching test"; "second control command" corresponds to "fault injection test". This embodiment also uses "first" and "second" as identification prefixes to distinguish the expected feedback results corresponding to different test scenarios, such as "first expected feedback result" corresponding to "normal system switching test"; "second expected feedback result" corresponding to "fault injection test".

[0049] The TCC dual-machine hot standby architecture provides three mutually exclusive control modes: A-series master control mode, B-series master control mode, and automatic failover mode (automatic mode). It's important to note that in the TCC dual-machine hot standby architecture, A-series and B-series are two completely identical hardware and software systems, serving as redundant backups for each other (i.e., one master and one standby). At any given time, only one of A-series and B-series is in "master control" mode, responsible for outputting train control commands; the other is in "hot standby" mode, synchronizing data in real time but not outputting data, ensuring system redundancy and reliability. Furthermore, through external control commands, A-series or B-series can be actively and forcibly switched to master control, i.e., "interventional failover." When there is no "interventional failover" in the TCC, the internal software logic autonomously determines the master / standby status, i.e., implementing "automatic mode." The specific explanations include the following: If the current master control system (e.g., system A) fails, the TCC will automatically trigger a shutdown and upgrade system B to master control. If the master control system is functioning normally, the current master control status will remain unchanged in automatic mode. Automatic mode is mutually exclusive with "system A master control" and "system B master control," meaning the system can only be in one of three states: "system A master control," "system B master control," or "automatic shutdown."

[0050] In this embodiment, the test control terminal (host computer) runs a pre-written automated test script (target script) and issues a first control command to the PLC. The purpose of this first control command is to force the first system (e.g., system A) in the TCC dual-machine hot standby architecture to switch to the master control system. The target script may include, but is not limited to, the following data information: The complete logic of "TCC normal system switching test" has been solidified, including: instruction issuance timing; interlocking rules (the master control states of the first system and the second system are mutually exclusive and cannot be master control at the same time); and the first expected result (such as the TCC should report the state of "the first system is master control").

[0051] Furthermore, it should be noted that before executing step 101, this embodiment of the application first performs system initialization, returning to the automated testing mode. The specific process is as follows: At the test control end, the staff runs a Python automated test script on the PC. This script calls the PLC's IP address through the pymodbus library to establish a network communication connection and then sends a reset command to the PLC. After receiving the command, the PLC's internal program forcibly sets two independent relay output contacts (denoted as Q0.0 and Q0.1) to the open state. These two contacts are used to simulate the "A-series contacts" and "B-series contacts" in traditional mechanical switches, respectively.

[0052] On the TCC side, since both Q0.0 and Q0.1 are in the off state, no DC24V high-level signal is detected in the DIA and DIB channels. According to the preset logic, it is identified as "automatic mode". Thus, the automatic failover logic of the dual-machine hot standby system takes over the control of the master-slave switching, and builds the initial baseline state for subsequent tests.

[0053] The essence of the initialization in this application embodiment is to restore the remote switching system to its original state of "no manual intervention," avoiding the influence of residual PLC touches on subsequent test results and ensuring the repeatability and consistency of the test process. Step 102: After receiving the first control instruction and performing an interlock check, the PLC controls the corresponding relay contact of the first system to close.

[0054] After receiving the first control command from the test control terminal, the PLC first executes its internal interlock check logic. After confirming that there are no conflicting commands or abnormal states, it drives the output circuit to close the relay contacts corresponding to the first system. Specifically, the execution flow of the interlock check is provided in this embodiment as follows: After the PLC receives the first control command, if it detects that the relay contact corresponding to the second system is currently in a closed state, it determines that it will refuse to execute the first control command and sends an error message to the test control terminal; if it detects that the relay contact corresponding to the second system is currently in an open state, it determines that it is safe to execute the system switching operation.

[0055] The interlocking check in this embodiment serves to ensure that the relay contacts of the first and second systems do not close simultaneously, thereby avoiding sending conflicting system-cutting signals to the TCC and preventing electrical short circuits or logical confusion.

[0056] Furthermore, after determining that the switching operation can be safely performed and before controlling the relay contacts corresponding to the first system to close, the embodiments of this application may add detailed steps, such as: the PLC controls the relay contacts corresponding to the first system and the second system to remain in the open state for a preset time according to the preset state machine anti-jitter logic, so as to simulate the physical dead zone characteristics of the mechanical rotary switch. After the preset time expires, the relay contacts corresponding to the first system are controlled to close.

[0057] The purpose of adding the above-mentioned detailed steps in this application embodiment is to: reproduce the "contact disconnection gap" during mechanical switch switching, avoid the PLC instantaneous signal causing TCC misjudgment timing, ensure that remote switching behavior is consistent with local operation behavior, thereby simulating physical dead zone and ensuring the authenticity of the test; by introducing a preset disconnection duration, the TCC anti-jitter and signal discrimination mechanism is triggered, effectively verifying its ability to recognize real switching commands and its anti-interference performance, thereby avoiding misjudgment and verifying anti-interference logic; force the two relays to disconnect synchronously and reserve a gap, eliminate the risk of "dual master control" overlap, improve the electrical safety and logic reliability of the switching process, thereby preventing signal conflict and strengthening safety.

[0058] Step 103: In remote mode, the power supply is connected to the first signal channel of the TCC through the relay contact corresponding to the first system that has been activated, and after the TCC acquires a high-level signal, the TCC performs the operation of switching the first system to the main control system.

[0059] In the pure remote mode where "PLC replaces traditional mechanical switches", the engaged first-series relay contacts connect a DC 24V high level to the first signal channel of the TCC (such as the DI_A port). After the TCC's safety acquisition board detects this high-level signal, it executes the operation of switching the first series to the master control system according to its internal safety logic.

[0060] The switching logic in step 103 is as follows: After the TCC detects a valid high level on the first channel, it confirms that the current instruction is "forced switch to the first system" and executes a master-slave switch, upgrading the first system to the master system and demoting the second system to the standby system. The corresponding signal path is: the PLC relay output is directly connected to the TCC DI channel, without an intermediate mode switching module.

[0061] Step 104: The test control terminal verifies whether the TCC switching action is successful based on the first expected feedback result in the target script.

[0062] The test control terminal reads the current master control status and system logs from the TCC feedback via the network and compares them with the first expected feedback result pre-written in the target script (e.g., "the first system is the master control, and the second system is the backup system") to complete automated verification: If the actual feedback from the TCC is consistent with the expected result → the TCC system switching test is deemed to have passed; if the actual feedback is inconsistent with the expected result (e.g., no system switching, incorrect system switching, or triggering of a fault alarm) → the test is deemed to have failed, and an exception log is recorded for problem localization.

[0063] After the test is completed, the test control terminal (host computer) script sends a reset command to the PLC. Upon receiving the command, the PLC controls all the relay output contacts (such as Q0.0 and Q0.1) corresponding to the first and second systems to disconnect, restoring the TCC's digital input (DI) ports to a state with no high-level input. The TCC then returns to automatic shutdown mode. Simultaneously, the test control terminal disconnects from the PLC's network connection, completing the entire remote automated testing process.

[0064] Steps 101-104 above constitute the remote fully automated test process for "TCC normal switching test". Below, this application embodiment also provides a remote fully automated test process for "TCC fault injection test". If the execution logic for the fault injection test and its corresponding second expected feedback result are pre-written in the target script, it will still be based on... Figure 1 The overall architecture of the test system is shown, and remote automated testing of the TCC switching system is achieved by "using PLC to replace traditional mechanical switches". Figure 7 As shown, the following specific implementation steps are provided for this embodiment: Step 201: The test control terminal sends a second control instruction to the PLC based on the target script. The second control instruction is a fault simulation instruction, which is used to trigger an illegal input scenario test.

[0065] The test control terminal (host computer) issues a second control instruction to the PLC based on a pre-written target script. This second control instruction is a fault simulation instruction. The purpose of the fault simulation instruction is to actively construct an "illegal input scenario" to test the fault tolerance and protection logic of the TCC under abnormal signals. The execution logic of the fault test (such as fault triggering methods and timing requirements) and the corresponding second expected feedback result (i.e., the safe operation that the TCC should perform under fault) are already embedded in the target script.

[0066] This step initiates a command to verify abnormal scenarios of the TCC switching function, which is different from normal switching tests and is used to verify the fault safety characteristics of the system.

[0067] Step 202: After receiving the second control command, the PLC temporarily releases the original interlock restrictions.

[0068] After receiving the second control command, the PLC temporarily releases the interlocking restriction between the first and second system relay contacts, which was enabled during normal system switching testing. The interlocking logic prevents both relays from engaging simultaneously during normal system switching, avoiding signal conflicts. The purpose of temporarily releasing the interlock is to proactively create an illegal scenario of "both system channels simultaneously inputting high levels" during fault testing. This is a state absolutely unacceptable under normal operation, and fault injection is achieved by releasing the interlock.

[0069] Step 203: The PLC controls the relay contacts corresponding to the first system and the relay contacts corresponding to the second system to close simultaneously. In remote mode, the power supply high level is simultaneously connected to the first signal channel and the second signal channel of the TCC. The first signal channel corresponds to the first system, and the second signal channel corresponds to the second system.

[0070] After the PLC releases the interlock, it controls the relay contacts corresponding to the first and second systems to simultaneously close. In pure remote mode, a high-level power supply (e.g., DC 24V) is simultaneously connected to both the first signal channel (corresponding to the first system) and the second signal channel (corresponding to the second system) of the TCC. Both channels being high simultaneously is a state that is physically impossible with traditional mechanical switches (mechanical switch positions are mutually exclusive, making it impossible to connect two paths simultaneously), representing a typical electrical fault / illegal input.

[0071] This step uses the electronic control capabilities of the PLC to simulate extreme fault scenarios that would not occur with a mechanical switch, in order to perform extreme testing of the TCC's safety logic.

[0072] Step 204: After the TCC detects that both the first and second channels are at a high level, it identifies the system switch as faulty and executes control operations.

[0073] After the TCC's safety acquisition board detects that the first and second channels are both at a high level, it identifies this state as a system switch failure (or "dual master control command conflict failure") based on its internal safety logic, and executes the corresponding fault handling control operation.

[0074] The fault diagnosis logic provided in this step is as follows: The TCC internally presets a state where "both channels are high simultaneously" as an illegal state, which is determined to be a failure of the physical switch or a short circuit in the line. Furthermore, the control operation direction provided is: the TCC will not perform any primary / standby switching action, but will enter a fault-tolerant protection state, the core of which is to maintain system stability and avoid unexpected failover.

[0075] Step 205: Based on the second expected feedback result in the target script, the test control terminal verifies whether the TCC executes the fault-tolerant protection operation under the fault condition that matches the second expected feedback result. The fault-tolerant protection operation includes at least the control operation that keeps the current master / standby state of the TCC from unexpectedly switching over.

[0076] The test control terminal reads the current master control status, fault logs, and other data fed back by the TCC, and compares them with the second expected feedback result pre-written in the target script to verify whether the TCC has performed the correct fault tolerance protection operation.

[0077] For example, the expected operation verification provided is: to focus on verifying whether the TCC maintains the current primary / standby status unchanged, without any unexpected primary / standby failover, and whether it outputs the corresponding fault alarm information. The provided test objective is: to confirm that the TCC can "refuse to operate" rather than "accidentally operate" when faced with illegal input, ensuring the safety and stability of the dual-machine hot standby system and verifying the effectiveness of its fault-safe design.

[0078] Steps 201-205 above constitute the test procedure for the "TCC Fault Injection Test". It should be noted that the system initialization steps and the reset operation after the test are completely consistent with the corresponding operations in steps 101-104 of the "TCC Normal System Switching Test" test procedure, and will not be repeated here.

[0079] Furthermore, in comparison Figure 1 and Figure 2 As can be seen from the overall architecture of the test system shown, the core difference between the two lies only in Figure 2 A "mode switching module" has been added, which enables TCC cutting system testing to be achieved through "PLC in parallel with traditional mechanical switches", and achieves remote automated control of TCC cutting system testing by relying on "remote + local" dual modes.

[0080] To avoid redundant explanations, the embodiments of this application, based on the technical solutions of steps 101-104 and 201-205 above, further elaborate on... Figure 2 When explaining the workflow of the overall structure of the test system shown, the focus will be on the working principle of the "mode switching module," and the specific explanation includes the following: (1) The mode switching module provides a double-pole double-throw physical switch, and the local control path and remote control path are divided at the electrical level. The mode switching module establishes a non-networked physical electrical connection with the PLC and TCC respectively.

[0081] The mode switching module uses a double-pole double-throw physical switch as its core carrier, dividing the system into two mutually exclusive control paths at the electrical wiring layer: one is a local control path, connecting to the existing three-position self-locking mechanical knob; the other is a remote control path, connecting to the relay output of the PLC. The module's connections to the PLC and TCC are all non-networked physical electrical connections (i.e., DC24V level signal connections), relying solely on physical contacts to forward signals, ensuring the reliability and security of the control link. This achieves physical electrical path isolation at the underlying architecture level.

[0082] (2) When the double-pole double-throw physical switch is switched to the local position, the mode switching module conducts the local control path, receives the manual control signal triggered by the physical knob, and selectively connects the high-level power supply to the first signal channel or the second signal channel of the TCC, supporting normal switching test or fault injection test performed on the TCC. The manual control signal corresponds to one of the three positions: first system forced main control, second system forced main control or automatic mode.

[0083] When the double-pole double-throw switch is switched to the local position, the internal physical contacts of the module connect the local control path while completely disconnecting the remote control path. The signal source is: receiving manual control signals from the original mechanical knob (corresponding to A-series main control, B-series main control, and automatic mode positions); signal forwarding is: selectively connecting the high-level power supply (DC 24V) to the first signal channel (corresponding to A-series) or the second signal channel (corresponding to B-series) of the TCC according to the knob position. This completely replicates the original manual system switching operation procedure, supporting on-site personnel to perform normal system switching tests or troubleshooting, and is fully compatible with the operating habits and TCC input logic before the modification. Therefore, when the double-pole double-throw physical switch is switched to the local position, the original manual operation logic can be reused.

[0084] (3) When the double-pole double-throw physical switch is switched to the remote position, the mode switching module connects the remote control path and connects the signal acquisition channels of the PLC and TCC. The PLC controls the power supply high level to selectively connect to the first signal channel or the second signal channel of the TCC, supporting normal switching test or fault injection test performed on the TCC.

[0085] When the double-pole double-throw switch is switched to the remote position, the internal physical contacts of the module connect the remote control path and simultaneously disconnect the local control path. In this path, the signal source is the automated control signal output by the PLC (generated by commands issued from the test control terminal); the signal forwarding method is as follows: according to the PLC control logic, the DC 24V high level is selectively connected to either the first or second signal channel of the TCC. Therefore, the system can achieve automated control based on the PLC, supporting unattended normal switching tests and fault injection tests, achieving the same automated testing effect as the PLC replacing the traditional mechanical switch method in a pure remote architecture (as shown in Figure 1). In summary, when the double-pole double-throw physical switch is switched to the remote position, it can receive PLC automated control commands.

[0086] In the embodiments of this application, using as Figure 2 The overall architecture of the testing system is such that the mode switching module achieves electrical isolation between "local" and "remote" modes through a physical switch, which retains the safety redundancy of manual on-site operation and maintenance while also enabling the high-efficiency capability of remote automated testing by PLC.

[0087] In summary, the remote automatic system switching test method and system for dual-machine hot standby in train control centers provided in this application embodiment can be implemented in the following two ways: Purely remote method: "PLC replaces traditional mechanical switches", directly bypassing the physical operation of manual knobs, and realizing purely remote automated switching tests.

[0088] Dual-mode compatibility: By connecting a PLC in parallel with a traditional mechanical switch, and using a dual-mode system of "remote + local", remote automated testing is achieved while retaining the ability for manual on-site maintenance.

[0089] In summary, both methods can fully realize the closed-loop process of TCC switchover testing: "initiating switchover command → TCC executing switchover → verifying switchover results", achieving remote fully automated control of TCC switchover testing and providing an efficient and reliable automated solution for TCC dual-machine hot standby switchover testing. Of particular note is that this application's embodiment can resolve the physical breakpoint of "master / standby switching" in TCC automated testing, enabling the test script to automatically execute the entire "run-system switching-verification-switchback" process, significantly improving regression testing efficiency. Simultaneously, utilizing the independent control contact characteristics of the PLC, it can simulate "double-closed" faults that physical mechanical switches cannot achieve, filling the gap in external input circuit fault diagnosis logic testing. Furthermore, this application's embodiment uses relay dry contact output, with electrical characteristics completely consistent with the original mechanical switch, requiring no modification to the internal circuitry of the device under test (TCC), and retains "local / remote" physical switching to ensure on-site laboratory maintenance safety. The PLC's action time is precisely controllable, and it can accurately test the TCC software's debouncing time window and critical response characteristics, effectively eliminating human error.

[0090] This application provides a computer-readable storage medium storing a computer program. When the computer program is executed by a processor, it implements the remote automatic system switching test method for dual-machine hot standby in a train control center as described above.

[0091] This application provides an electronic device, which includes at least one processor, at least one memory and a bus connected to the processor; wherein the processor and the memory communicate with each other through the bus; the processor is used to call program instructions in the memory to execute the remote automatic switching test method for dual-machine hot standby in the train control center as described above.

[0092] The processor contains a kernel, which retrieves the corresponding program unit from memory. One or more kernels can be configured. By adjusting kernel parameters, a complete closed loop can be constructed: "Initiating a switching command → PLC outputs a level signal → TCC executes the switching → Remotely verifies the switching result." This achieves remote automation of the entire switching test process, effectively improving testing efficiency and safety, and providing an efficient and reliable automated solution for TCC dual-machine hot standby master-slave switchover testing.

[0093] This application also provides a computer program product that, when executed on a data processing device, is suitable for executing a program that initializes a remote automatic switching test method for dual-machine hot standby in a train control center.

[0094] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0095] In a typical configuration, the device includes one or more processors (CPUs), memory, and a bus. The device may also include input / output interfaces, network interfaces, etc.

[0096] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM, and memory includes at least one memory chip. Memory is an example of computer-readable media.

[0097] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0098] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0099] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0100] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A remote automatic system switching test method for dual-machine hot standby in train control center, characterized in that, The method includes: The test control terminal sends a first control instruction to the PLC based on the target script. The first control instruction is used to instruct the first system to be switched to the master control system. The target script is pre-written with the execution logic of the TCC normal system switching test and its corresponding first expected feedback result. In the TCC dual-machine hot standby architecture, the first system and the second system are redundant backups of each other and their master control states are mutually exclusive. After receiving the first control command and performing an interlock check, the PLC controls the corresponding relay contact of the first system to close. In remote mode, the power supply is connected to the first signal channel of the TCC through the relay contact corresponding to the first system that has been activated, and after the TCC acquires a high-level signal, the TCC performs the operation of switching the first system to the main control system. The test control terminal verifies whether the TCC switching action is successful based on the first expected feedback result in the target script.

2. The method according to claim 1, characterized in that, After receiving the first control command, the PLC performs an interlock check and controls the corresponding relay contacts of the first system to close, including: After the PLC receives the first control instruction, if it detects that the relay contact corresponding to the second system is currently in a closed state, it determines that it will refuse to execute the first control instruction and sends an error message back to the test control terminal. If it is detected that the relay contact corresponding to the second system is currently in an open state, it is determined that the system switching operation can be safely performed.

3. The method according to claim 2, characterized in that, After determining that it is safe to perform the system switching operation, and before controlling the relay contacts corresponding to the first system to close, the method further includes: The PLC controls the relay contacts corresponding to the first system and the second system to remain in the open state for a preset time according to the preset state machine anti-jitter logic, so as to simulate the physical dead zone characteristics of mechanical switches. After the preset time expires, the PLC controls the relay contacts corresponding to the first system to close.

4. The method according to claim 1, characterized in that, The target script also pre-writes the execution logic for the fault injection test and its corresponding second expected feedback result. The method further includes: The test control terminal sends a second control instruction to the PLC based on the target script. The second control instruction is a fault simulation instruction, which is used to trigger an illegal input scenario test. After receiving the second control command, the PLC temporarily releases the original interlock restrictions; The PLC controls the relay contacts corresponding to the first system and the relay contacts corresponding to the second system to simultaneously engage. In remote mode, a high power supply level is simultaneously connected to the first signal channel and the second signal channel of the TCC. The first signal channel corresponds to the first system, and the second signal channel corresponds to the second system. After the TCC detects that both the first channel and the second channel are at a high level, it identifies the system switch as faulty and executes control operations. The test control terminal verifies whether the TCC performs a fault-tolerant protection operation under fault conditions that matches the second expected feedback result in the target script. The fault-tolerant protection operation includes at least a control operation that keeps the TCC in its current primary / standby state from experiencing an unexpected failover.

5. The method according to claim 1 or 4, characterized in that, The method further includes: A mode switching module is used to provide a double-pole double-throw physical switch, which divides the local control path and the remote control path at the electrical level. The mode switching module establishes a non-networked physical electrical connection with the PLC and TCC respectively. When the double-pole double-throw physical switch is switched to the local position, the mode switching module activates the local control path, receives the manual control signal triggered by the physical knob, and selectively connects the high-level power supply to the first signal channel or the second signal channel of the TCC, supporting the normal switching test or the fault injection test performed on the TCC. The manual control signal corresponds to one of the three positions: first system forced main control, second system forced main control, or automatic mode. When the double-pole double-throw physical switch is switched to the remote position, the mode switching module connects the remote control path, connecting the signal acquisition channels of the PLC and TCC. The PLC controls the selective connection of the high-level power supply to the first signal channel or the second signal channel of the TCC, supporting the normal switching test or the fault injection test performed on the TCC.

6. The method according to any one of claims 1 to 4, characterized in that, The method further includes: After the TCC normal switching test and / or the fault injection test are completed, the test control terminal sends a reset command based on the target script; After the PLC receives the reset command, it controls the relays corresponding to the first system and the relays corresponding to the second system to be in the disconnected state, so that the TCC returns to the automatic mode. The automatic mode is the third working mode in the TCC dual-machine hot standby architecture, which is different from the first system forced master control mode and the second system forced master control mode. In the automatic mode, the TCC autonomously decides the master and standby system status by its own dual-machine hot standby shutdown logic. The test control terminal disconnects from the network communication connection of the PLC.

7. A remote automatic switching test system for dual-machine hot standby in a train control center, applied to the method as described in any one of claims 1 to 6, characterized in that, The system includes at least: a test control terminal, a PLC, and a TCC.

8. The system according to claim 7, characterized in that, The system also includes a mode switching module, which provides a double-pole double-throw physical switch to divide the local control path and the remote control path at the electrical level. The mode switching module establishes a non-networked physical electrical connection with the PLC and the TCC respectively. When the double-pole double-throw physical switch is switched to the local position, the mode switching module activates the local control path, receives the manual control signal triggered by the physical knob, and selectively connects the high-level power supply to the first signal channel or the second signal channel of the TCC, supporting the normal switching test or the fault injection test performed on the TCC. The manual control signal corresponds to one of the three positions: first system forced main control, second system forced main control, or automatic mode. When the double-pole double-throw physical switch is switched to the remote position, the mode switching module connects the remote control path, connecting the signal acquisition channels of the PLC and TCC. The PLC controls the selective connection of the high-level power supply to the first signal channel or the second signal channel of the TCC, supporting the normal switching test or the fault injection test performed on the TCC.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, which, when executed by a processor, implements the remote automatic system switching test method for dual-machine hot standby in a train control center as described in any one of claims 1-6.

10. An electronic device, characterized in that, The device includes at least one processor, and at least one memory and bus connected to the processor; The processor and the memory communicate with each other via the bus. The processor is used to call program instructions in the memory to execute the remote automatic system switching test method for dual-machine hot standby in the train control center as described in any one of claims 1-6.

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