Emergency braking loop switching method and circuit in vehicle circuit fault mode

Abstract

The invention relates to the technical field of subway control circuits, and discloses an emergency braking loop switching method and circuit in a vehicle circuit fault mode. According to the method, double emergency braking control loops which are completely identical in structure and triggering condition are arranged in a vehicle, in a normal mode, a first emergency braking control loop is activated to maintain a relieving state, and a second emergency braking control loop is powered off and standby. And when emergency braking is triggered and locking cannot be achieved due to the fact, the emergency braking change-over switch is operated, and the control right is transferred from the first emergency braking control loop to the second emergency braking control loop. According to the design, the fault handling efficiency and the train usability are improved, and it is ensured that the train can be maintained to run to the garage to be overhauled after faults occur.

Description

Technical Field

[0001] This invention relates to the field of subway control circuit technology, and discloses a method and circuit for switching emergency braking circuits under vehicle circuit fault modes. Background Technology

[0002] The emergency braking function of subway trains is crucial for ensuring operational safety. Its triggering conditions are complex and varied, including manual activation of the emergency brake button, power failure in the emergency electrical circuit, overspeed, insufficient total air pressure, unoccupied driver's cab, failure of the warning device to respond within a specified time, and ATP protection. In addition, some systems also involve conditions such as passive obstacle triggering, derailment detection, or the opening of emergency evacuation doors.

[0003] To improve train availability, existing technologies typically include bypass switches in the emergency braking circuit for most triggering conditions, so that the failure point can be temporarily bypassed in the event of a single node failure, allowing the train to continue operating under manual monitoring and avoiding rescue operations.

[0004] However, the contact status in the emergency braking circuit is independent of the contacts monitored by the train control and monitoring system. If the emergency braking circuit contacts fail but the monitoring contacts show normal status, operators will not be able to quickly locate the cause of the fault and will have to rely on guesswork to try operating the bypass switch one by one, which greatly reduces the efficiency of fault handling and may even lead to unnecessary rescue operations. Summary of the Invention

[0005] To address the aforementioned technical shortcomings, the purpose of this invention is to provide an emergency braking circuit switching method and circuit under vehicle circuit fault mode, which solves the problem of low handling efficiency when emergency braking circuit faults cannot be quickly located in the prior art.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions: In a first aspect, the present invention provides a method for switching emergency braking circuits under vehicle circuit failure mode, comprising: A first emergency braking control circuit and a second emergency braking control circuit are provided in the vehicle. The first emergency braking control circuit and the second emergency braking control circuit have exactly the same triggering conditions and structure, and are used to independently control the application and relief of emergency braking. In normal operation mode, the first emergency braking control circuit is activated to maintain the emergency braking relief state, while the second emergency braking control circuit is kept in a de-energized state. When emergency braking is triggered, the cause of the emergency braking is monitored through the train control and monitoring system. When the cause of emergency braking cannot be locked or a short circuit fault occurs in the first emergency braking control circuit, the emergency braking switch is operated to switch from the first circuit position to the second circuit position, the second emergency braking control circuit is activated and the first emergency braking control circuit is cut off. If the emergency braking is relieved, the second emergency braking control circuit remains active and the train continues to run.

[0007] Preferably, in one possible implementation of the first aspect, the triggering conditions for the first emergency braking control circuit and the second emergency braking control circuit include: the manual driving alert device timeout, the train running direction change, the train speeding, the total air pressure undervoltage, the absence of a driver's cab, and ATP emergency braking protection.

[0008] Preferably, in one possible implementation of the first aspect, the first emergency braking control circuit and the second emergency braking control circuit respectively control the first emergency braking contactor and the second emergency braking contactor, whose contacts are connected in parallel in the train line of the emergency braking execution circuit to control the train emergency braking solenoid valve.

[0009] Preferably, in one possible implementation of the first aspect, the cause of emergency braking that cannot be identified includes emergency braking triggered by an unknown cause as indicated by the train control and monitoring system.

[0010] Preferably, in one possible implementation of the first aspect, the emergency braking switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively control the first emergency braking control circuit and the second emergency braking control circuit.

[0011] Preferably, in one possible implementation of the first aspect, operating the emergency braking switch includes manually switching the emergency braking switch from a first circuit position to a second circuit position, thereby realizing the control switching from the first emergency braking control circuit to the second emergency braking control circuit.

[0012] In a second aspect, the present invention provides an emergency braking circuit switching circuit under vehicle circuit failure mode, for implementing an emergency braking circuit switching method under vehicle circuit failure mode as described in the first aspect, including a first emergency braking control circuit, a second emergency braking control circuit, an emergency braking switching switch, a first emergency braking contactor, a second emergency braking contactor, and an emergency braking execution circuit. The first emergency braking control circuit and the second emergency braking control circuit have exactly the same structure and triggering conditions, and control the first emergency braking contactor and the second emergency braking contactor respectively. The contacts of the first emergency brake contactor and the second emergency brake contactor are connected in parallel in the train line of the emergency brake execution circuit to control the train emergency brake solenoid valve. The emergency brake switching switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively activate the first emergency brake control circuit or the second emergency brake control circuit. In normal operation mode, the emergency brake switch is set to the first circuit position, which activates the first emergency brake control circuit to maintain the emergency brake relief state, while keeping the second emergency brake control circuit in a de-energized state. When the cause of emergency braking cannot be locked or a short circuit fault occurs in the first emergency braking control circuit, the emergency braking switch is operated to switch from the first circuit position to the second circuit position, activating the second emergency braking control circuit and disconnecting the first emergency braking control circuit. If the emergency braking is relieved, the second emergency braking control circuit is kept active to keep the train running.

[0013] The beneficial effects of the present invention are as follows: by setting up dual emergency braking control circuits, the present invention activates the first emergency braking control circuit to maintain the relief state in normal mode, while the second emergency braking control circuit serves as a backup in case of power failure.

[0014] When emergency braking is triggered and the cause of the trigger cannot be identified through the train monitoring system, the driver can manually switch the two-position bypass switch to transfer control from the first emergency braking control circuit to the second emergency braking control circuit, thereby cutting off the first emergency braking control circuit and activating the second circuit.

[0015] Since the triggering conditions and structure of the two circuits are completely consistent, covering all key conditions such as manual alert timeout, overspeed, and total wind undervoltage, the contactor contacts are connected in parallel to control the solenoid valve to ensure the complete braking function after switching.

[0016] This design avoids the risk of a single point of failure causing the entire vehicle to fail, while also achieving circuit isolation through independent monitoring components to prevent the spread of the fault.

[0017] If the braking is relieved after the operation, the second emergency braking control circuit can remain active and continue to operate without immediate rescue, significantly improving the efficiency of fault handling and train availability. The original circuit can be repaired after returning to the depot, balancing safety and operational continuity. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This application provides a flowchart of an emergency braking circuit switching method under vehicle circuit fault mode.

[0020] Figure 2 This application provides a first emergency braking control circuit diagram under vehicle circuit failure mode.

[0021] Figure 3 This application provides a second emergency braking control circuit diagram under vehicle circuit failure mode.

[0022] Figure 4 This application provides an emergency braking execution circuit diagram under vehicle circuit failure mode. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] To facilitate understanding of the technical solution of this application, this application will first be described. Figure 2 , Figure 3 and Figure 4 The designations of electrical components in the document are explained as follows:

[0025] Example 1: As Figure 1 As shown, the present invention provides a method for switching emergency braking circuits under vehicle circuit fault mode, including: A first emergency braking control circuit and a second emergency braking control circuit are installed in the vehicle. The first emergency braking control circuit and the second emergency braking control circuit have exactly the same triggering conditions and structure, and are used to independently control the application and relief of emergency braking.

[0026] In this embodiment, both the first and second emergency braking control circuits are designed as independent circuits to ensure reliable operation in both normal and fault modes. Specifically, each circuit includes the same triggering conditions, including manual driving alert device timeout, change in train direction, train overspeed, low total air pressure, no driver's cab occupied, and ATP emergency braking protection.

[0027] Structurally, the first emergency brake control circuit controls the first emergency brake contactor, while the second emergency brake control circuit independently controls the second emergency brake contactor. The contacts of the contactors are connected in parallel in the train line of the emergency brake execution circuit, which runs through the entire train and is used to directly control the train's emergency brake solenoid valve.

[0028] The circuit design follows the "double-break" safety principle, which means disconnecting both the positive and negative terminals of the power supply through circuit breakers to avoid malfunctions caused by single-point faults. Each circuit also includes an independent monitoring element to ensure complete isolation and independent operation of the circuit.

[0029] In normal operating mode, the first emergency braking control circuit is activated to maintain the emergency braking relief state, while the second emergency braking control circuit is kept in a de-energized state.

[0030] In this embodiment, the emergency brake switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively control the first emergency brake control circuit and the second emergency brake control circuit. When the emergency brake switch is set to the first circuit position, the first emergency brake control circuit is activated. The first emergency brake control circuit is in operation. When the circuit is energized, the emergency brake is released; when the circuit is de-energized, the emergency brake is applied. At the same time, the second emergency brake control circuit remains de-energized.

[0031] When emergency braking is triggered, the cause of the emergency braking is monitored through the train control and monitoring system.

[0032] In this embodiment, when emergency braking is triggered, the train control and monitoring system displays the reason for the emergency braking in real time on its monitoring screen, including status information such as the air pressure gauge and indicator lights. If the train control and monitoring system screen reports an emergency braking triggered for an unknown reason, it indicates that the specific fault point cannot be directly identified.

[0033] If the cause of emergency braking cannot be locked, operate the emergency braking switch to switch from the first circuit position to the second circuit position, activate the second emergency braking control circuit and disconnect the first emergency braking control circuit.

[0034] In this embodiment, when the train control and monitoring system displays an emergency braking event triggered by an unknown cause and the specific fault point cannot be located, the driver manually operates the emergency braking switch. This switch is a two-position bypass switch with clearly marked first and second circuit positions. During operation, the switch is switched from the first circuit position to the second circuit position, mechanically cutting off the power supply path to the first emergency braking control circuit while simultaneously activating the power supply path to the second emergency braking control circuit. This switching action completely de-energizes the first circuit, causing it to exit control mode, and the second circuit, after being energized, takes over the emergency braking control function. After the switch, the second circuit independently monitors all triggering conditions, such as the manual driving alert device timeout and train speeding, and manages the execution circuit through the emergency braking contactor contacts it controls.

[0035] If the emergency braking is relieved, the second emergency braking control circuit remains active and the train continues to run.

[0036] In this embodiment, after switching the emergency brake switch to the second circuit position, if the emergency braking is successfully released, it indicates that the second emergency brake control circuit has normally taken over the control function. At this time, keeping the emergency brake switch in the second circuit position ensures that the second emergency brake control circuit remains active, independently monitoring all triggering conditions and controlling the second emergency brake contactor. The train can maintain normal operation under the control of the second circuit and continue to complete the day's operation tasks. After the train returns to the depot, the faulty nodes in the original first emergency brake control circuit are inspected and maintained to avoid mid-journey passenger evacuation or rescue.

[0037] If the emergency braking does not relieve the situation, it shall be handled in accordance with the original relevant operating procedures.

[0038] Example 2: The present invention provides an emergency braking circuit switching circuit under vehicle circuit fault mode, including a first emergency braking control circuit, a second emergency braking control circuit, an emergency braking switching switch, a first emergency braking contactor, a second emergency braking contactor, and an emergency braking execution circuit.

[0039] The first emergency braking control circuit and the second emergency braking control circuit have exactly the same structure and triggering conditions, and control the first emergency braking contactor and the second emergency braking contactor respectively.

[0040] The first emergency braking control circuit is as follows: Figure 2As shown, this circuit maintains the emergency braking release state under normal operating mode. The circuit contains several key components: the emergency brake control circuit breaker EBCB is used for main power control, ensuring the circuit is energized after the train is awakened; the emergency brake circuit selection switch EBLS is defaulted to the first circuit position, at which point its contacts close to activate the circuit; the energization state of the first emergency brake contactor EBK1 coil determines the application or release of emergency braking. Triggering conditions include the driver's cab occupancy relay COR detecting the driver's cab occupancy status, the ATO mode relay ATOMR monitoring the automatic operation mode, and the alert button delay relay DMR responding to manual driving alert operations. During normal operation, when the train is awakened and EBCB is closed, DC 110V power is supplied to the circuit. If none of the triggering conditions are met, the EBK1 coil is energized, and the contacts remain closed, thus maintaining the emergency braking release. Conversely, if any condition is triggered, the EBK1 coil de-energizes, and the contacts open. The circuit also includes a first emergency brake circuit breaker EBL1CB, used to automatically trip the protection circuit in the event of a short-circuit fault, ensuring system safety.

[0041] The second emergency braking control circuit is as follows: Figure 3 As shown, this circuit serves as a redundant backup, with an identical structure and triggering conditions to the first circuit. However, it remains de-energized and on standby under normal conditions, activating only during fault switching. The circuit components include the second emergency braking circuit breaker EBL2CB and the second emergency braking contactor EBK2, designed symmetrically to the first circuit to ensure seamless takeover control. In normal operation, the emergency braking circuit selector switch EBLS is in the first circuit position. Therefore, the EBLS contacts in the second circuit are open, causing the entire circuit to lose power. The EBK2 coil is not energized, and the contacts remain open. The circuit triggering conditions cover manual driving alert device timeout, train direction change, overspeed, low total wind pressure, no driver's cab occupancy, and ATP emergency braking protection. When switching is required, EBLS is switched to the second circuit position, and the EBLS contacts close, activating the second circuit. At this time, if any condition is triggered, the EBK2 coil is energized, and the contacts close. After activation, the second circuit independently monitors all conditions, ensuring the integrity of the emergency braking function and improving system reliability.

[0042] The contacts of the first and second emergency brake contactors are connected in parallel in the train line of the emergency brake execution circuit to control the train's emergency brake solenoid valve.

[0043] Emergency braking execution circuit diagram as follows Figure 4As shown, this circuit integrates the outputs of the first and second control circuits, and its parallel contact design ensures reliable control of the brake solenoid valve when either circuit is activated. Circuit components include the emergency brake relay EBR, the emergency brake solenoid valve EBV, and the emergency brake train line circuit breaker EBLCB. The EBLCB closes after the train is awakened, providing DC 110V power throughout the train. The key to the execution circuit lies in the parallel connection of the contacts of the first emergency brake contactor EBK1 and the second emergency brake contactor EBK2 within the train line. In normal mode, when the first circuit is activated and the EBK1 contact is closed, power is supplied to the EBR and EBV through the parallel path, energizing the EBR coil and energizing the EBV, thus maintaining the emergency brake in a released state. If either the EBK1 or EBK2 contact is open, the power path is cut off, the EBR and EBV are de-energized, and the emergency brake is immediately applied. This parallel structure ensures redundancy: when switching to the second circuit, the EBK2 contact can maintain power supply without relying on the original circuit.

[0044] The emergency braking (EBR) execution circuit is also connected to the train control and monitoring system, providing real-time feedback on the EBR status for monitoring. The circuit design follows a double-break principle, with EBK1 and EBK2 contacts controlling the positive and negative terminals respectively, ensuring safety and reliability. In fault scenarios, such as a short circuit in the first circuit preventing the EBK1 contact from closing, switching to the second circuit closes the EBK2 contact, energizing the execution circuit to release the brakes and allow the train to continue running. The entire circuit runs through the lead car and the last car, ensuring synchronized emergency braking across the entire train.

[0045] The emergency brake switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively activate the first emergency brake control circuit or the second emergency brake control circuit.

[0046] In normal operation mode, the emergency brake switch is set to the first circuit position, which activates the first emergency brake control circuit to maintain the emergency brake relief state, while keeping the second emergency brake control circuit in a de-energized state.

[0047] When emergency braking is triggered and the cause cannot be identified, the emergency braking switch is operated to switch from the first circuit position to the second circuit position, activating the second emergency braking control circuit and disconnecting the first emergency braking control circuit. If the emergency braking is relieved, the second emergency braking control circuit is kept active to maintain train operation.

[0048] In this embodiment, after the train is powered on and awakened, the emergency brake control circuit breaker EBCB and the emergency brake train line circuit breaker EBLCB close, and the train is supplied with DC 110V power. The emergency brake circuit selection switch EBLS is set by default to the "first emergency brake control circuit" position (first circuit position). When EBLS closes the contacts of the first emergency brake control circuit, the contacts of the second emergency brake control circuit open, the second emergency brake control circuit is de-energized, the coil of the second emergency brake contactor EBK2 is not energized, and the contacts open.

[0049] If any of the following conditions are met, the coil of the first emergency brake contactor EBK1 will lose its magnetism, the contacts will open, and combined with the state of EBK2, the power supply to the emergency brake relay EBR and the emergency brake solenoid valve EBV will be disconnected, and emergency braking will be applied.

[0050] Condition 1: Neither the local nor remote driver's cab is occupied, and the driver's cab occupancy relay COR is not energized.

[0051] Condition 2: The train is not in ATO mode and the ATO mode relay ATOMR is not energized; during train operation, the local controller's warning button is not pressed within the specified time and the warning button delay relay DMR is de-energized; and the warning bypass switch DMPS is not operated to the bypass position and the DMPS contacts are not closed.

[0052] Condition 3: During train movement, when the zero-speed relay ZVR is not energized, the direction of the local controller changes.

[0053] Condition 4: When the local or remote ATC outputs emergency braking, the ATC emergency relay ATCEB is not energized, and the ATC fault isolation switch ATCFS is not operated to the bypass position, and the ATCFS contacts are not closed.

[0054] Condition 5: The local or remote electronic brake control unit (EBCU) outputs emergency braking.

[0055] Condition 6: When the local or remote emergency braking button EMPB is pressed, the EMPB contacts open.

[0056] Condition 7: The local or remote brake main air pipe pressure switch LMPRS detects low brake main air pipe pressure, and the main air undervoltage bypass switch LMBPS is not operated to the bypass position, so the LMBPS contacts are open.

[0057] When the emergency braking trigger condition is not triggered, or after the corresponding bypass switch is operated, the first emergency braking contactor EBK1 will be energized and the contacts will close, the emergency braking execution circuit will be energized, the emergency braking relay EBR and the emergency braking solenoid valve EBV will be energized, and the emergency braking will be relieved.

[0058] When a contact in the first emergency braking control circuit fails to close due to a fault, and other contacts of the same relay or device monitored by the TCMS are in normal condition, the cause of the fault cannot be immediately identified; or when a short circuit fault occurs in the first emergency braking control circuit and the circuit breaker EBL1CB of the first emergency braking circuit trips, the emergency braking circuit selector switch EBLS can be selected to the "second emergency braking control circuit" position (second circuit position), so that the same emergency braking control circuit can take over, achieving complete redundancy, improving the reliability of the system, and reducing the probability of rescue.

[0059] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for switching emergency braking circuits under vehicle circuit fault mode, characterized in that, include: A first emergency braking control circuit and a second emergency braking control circuit are provided in the vehicle. The first emergency braking control circuit and the second emergency braking control circuit have exactly the same triggering conditions and structure, and are used to independently control the application and relief of emergency braking. In normal operation mode, the first emergency braking control circuit is activated to maintain the emergency braking relief state, while the second emergency braking control circuit is kept in a de-energized state. When emergency braking is triggered, the cause of the emergency braking is monitored through the train control and monitoring system. When the cause of emergency braking cannot be locked or a short circuit fault occurs in the first emergency braking control circuit, the emergency braking switch is operated to switch from the first circuit position to the second circuit position, the second emergency braking control circuit is activated and the first emergency braking control circuit is cut off. If the emergency braking is relieved, the second emergency braking control circuit remains active and the train continues to run.

2. The emergency braking circuit switching method under vehicle circuit fault mode according to claim 1, characterized in that, The triggering conditions for the first and second emergency braking control circuits include: the manual driving alert device timeout, the train's direction of travel change, the train speeding, the total air pressure being low, the driver's cab being unoccupied, and ATP emergency braking protection.

3. The emergency braking circuit switching method under vehicle circuit fault mode according to claim 1, characterized in that, The first emergency braking control circuit and the second emergency braking control circuit control the first emergency braking contactor and the second emergency braking contactor respectively. Their contacts are connected in parallel in the train line of the emergency braking execution circuit to control the train emergency braking solenoid valve.

4. The emergency braking circuit switching method under vehicle circuit fault mode according to claim 1, characterized in that, The inability to pinpoint the cause of emergency braking includes emergency braking triggered by unknown reasons as indicated by the train control and monitoring system.

5. The emergency braking circuit switching method under vehicle circuit fault mode according to claim 1, characterized in that, The emergency brake switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively control the first emergency brake control circuit and the second emergency brake control circuit.

6. The emergency braking circuit switching method under vehicle circuit fault mode according to claim 5, characterized in that, The operation of the emergency braking switch includes manually switching the emergency braking switch from the first circuit position to the second circuit position, thereby realizing the control switching from the first emergency braking control circuit to the second emergency braking control circuit.

7. An emergency braking circuit switching circuit under vehicle circuit fault mode, characterized in that, The circuit is used to implement an emergency braking circuit switching method under a vehicle circuit fault mode as described in claims 1 to 6, including a first emergency braking control circuit, a second emergency braking control circuit, an emergency braking switching switch, a first emergency braking contactor, a second emergency braking contactor, and an emergency braking execution circuit. The first emergency braking control circuit and the second emergency braking control circuit have exactly the same structure and triggering conditions, and control the first emergency braking contactor and the second emergency braking contactor respectively. The contacts of the first emergency brake contactor and the second emergency brake contactor are connected in parallel in the train line of the emergency brake execution circuit to control the train emergency brake solenoid valve. The emergency brake switching switch is a two-position switching bypass switch, including a first circuit position and a second circuit position, which respectively activate the first emergency brake control circuit or the second emergency brake control circuit. In normal operation mode, the emergency brake switch is set to the first circuit position, which activates the first emergency brake control circuit to maintain the emergency brake relief state, while keeping the second emergency brake control circuit in a de-energized state. When the cause of emergency braking cannot be locked or a short circuit fault occurs in the first emergency braking control circuit, the emergency braking switch is operated to switch from the first circuit position to the second circuit position, activating the second emergency braking control circuit and disconnecting the first emergency braking control circuit. If the emergency braking is relieved, the second emergency braking control circuit is kept active to keep the train running.

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