Method for detecting state of train brake output loop

Abstract

According to the train brake output loop state detection method, a state detection subsystem is designed in a brake output loop and comprises an output control unit, an input acquisition unit, an output unit and a state detection unit; the detection method comprises the steps of large loop state detection and middle loop state detection, and detection coverage of the state of the whole brake output loop is achieved. After the state detection unit receives a periodic control signal of the output control unit, detection on the state of the brake output loop is started, and detected state information is fed back to the output control unit; according to the detection method, the state of the brake output loop is continuously monitored in real time in the whole period of state verification after the brake equipment is powered on, runs and stops. According to the detection method, the problem that the brake output loop state real-time detection function is lacked in the train running process is effectively solved, and the requirement for continuous safety monitoring of the power-on brake system in the whole running cycle of the railway train is met.

Description

Technical Field

[0001] This invention relates to the field of railway signaling, and more specifically to a method for detecting the status of train brake output circuit. Background Technology

[0002] In the field of railway train control and signaling, the safety and reliability of train operation are directly related to passenger safety, freight transport safety, and the operational order of railway lines. Among these, the train braking control system, as a key component of the train safety assurance system, directly determines whether the train can accurately respond to braking commands under various abnormal conditions, avoiding major safety accidents caused by brake failure. The brake output circuit, as the "last execution channel," plays a crucial role in transmitting the emergency braking control signal stably and accurately to the braking equipment when the train triggers emergency braking conditions, ensuring the reliable operation of the braking equipment. The integrity and stability of this circuit directly determine whether the emergency braking command can be effectively implemented. It is a core prerequisite for ensuring that the train avoids dangerous conditions and achieves a safe stop, and has an irreplaceable and decisive impact on the safety redundancy capability and risk prevention level of the railway transportation system.

[0003] Currently, to improve the safety and reliability of energized braking output, the industry generally adopts a dual-machine redundancy design scheme. This involves configuring two independent output relays for each machine, and using combinational logic of the relay nodes to transmit braking signals. Under normal operating conditions, the two relays are energized synchronously, and their nodes combine to form a complete energized braking output circuit. Basic safety redundancy is achieved through hardware combinational logic. In this design architecture, the safety of the energized braking output highly depends on the inherent safety characteristics of the dual-machine output relays to ensure the basic safety of the circuit. Currently, the common method for detecting the state of the energized braking output circuit is to perform a one-time continuity self-test during the braking test phase at the train start-up stage (or before departure) to verify whether the initial state of the circuit is normal.

[0004] The aforementioned conventional design has significant technical flaws: the status check of the energized braking output circuit is limited to the braking test during train startup (or before departure). During normal locomotive operation, this circuit is susceptible to factors such as line wear, loose joints, cable aging, poor contact due to vibration, or line breakage caused by external impacts, leading to open circuits or continuity failures. More critically, during the continuous operation phase after train startup, there is a lack of a real-time dynamic monitoring mechanism for abnormal states of this circuit (especially critical faults like open circuits). When an open circuit occurs, operators cannot obtain real-time fault information, resulting in delayed troubleshooting and repair. If an open circuit fault occurs during operation, even if the dual-motor relays execute the braking command normally when the train triggers emergency braking, the energized braking control signal cannot be transmitted to the braking equipment through the faulty circuit, directly causing emergency braking failure. This prevents the train from stopping safely as instructed, greatly increasing the risk of railway train accidents and seriously threatening railway train operation safety. Summary of the Invention

[0005] To address the shortcomings of traditional train braking control systems in monitoring the status of the energized braking output circuit, this invention provides a highly reliable and safe method for detecting the status of the train braking output circuit. This method aims to accurately determine whether there are any abnormalities in the connection status of the train's energized braking output circuit, filling a gap in the monitoring capabilities of traditional systems in this area.

[0006] This invention provides a method for detecting the status of a train braking output circuit. The braking output circuit refers to the entire connection circuit from the external braking power supply to the braking device. A status detection subsystem is designed within the braking output circuit, comprising an output control unit, an input acquisition unit, an output unit, and a status detection unit. The status detection subsystem adopts a dual-machine hot standby redundant architecture, with each functional unit configured in a dual-machine operation mode (A machine and B machine). The output control unit and input acquisition unit both employ a "two-out-of-two" architecture composed of two processors with identical functions.

[0007] The detection methods are large circuit state detection and medium circuit state detection, respectively, to achieve detection coverage of the entire braking output circuit state; the large circuit refers to the connection circuit in the braking output circuit excluding the output unit, and the medium circuit refers to the connection circuit in the braking output circuit from the external braking power supply to the output end of the output unit.

[0008] After receiving the periodic control signal from the output control unit, the status detection unit starts detecting the status of the braking output circuit and feeds back the detected status information to the output control unit.

[0009] The detection method enables real-time continuous monitoring of the status of the braking output circuit throughout the entire cycle from powering on the braking device to the post-stop verification.

[0010] The train brake output circuit status detection method of the present invention effectively solves the lack of real-time detection function of brake output circuit status during train operation, and meets the continuous safety monitoring requirements of the energized braking system throughout the entire operation cycle of railway trains. Attached Figure Description

[0011] Figure 1 Schematic diagram of the braking output circuit status detection principle

[0012] Figure 2 Schematic diagram of relay output node combination for energized braking device Detailed Implementation

[0013] The features and advantages of the present invention will be described in detail below with reference to specific embodiments. This content will help those skilled in the art to further understand the present invention, but it does not limit the present invention in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the inventive concept, and these all fall within the protection scope of the present invention.

[0014] The method for detecting the status of the train brake output circuit described in this invention aims to achieve real-time detection of the status of the train brake output circuit.

[0015] The "brake output circuit" specifically refers to the entire connection circuit from the external brake power supply to the brake device, and the "brake output circuit status" refers to the connection status of the brake output circuit.

[0016] The braking device described in this invention specifically refers to an energized braking device.

[0017] The train brake output circuit status detection method of the present invention consists of two parts: large circuit status detection and medium circuit status detection. The detection coverage of the entire brake output circuit status is achieved through large circuit status detection and medium circuit status detection.

[0018] To implement the braking output circuit state detection method described in this invention, a state detection subsystem is designed, specifically including an output control unit, an input acquisition unit, an output unit, and a state detection unit. To ensure the safety and reliability of state detection, the state detection subsystem adopts a dual-machine hot standby redundant architecture. Each functional unit is configured with a dual-machine operation mode (A machine and B machine). The output control unit and input acquisition unit both adopt a "two-out-of-two" architecture consisting of two processors (CPU1 / CPU2) with identical functions.

[0019] The term "large circuit" refers to the braking output circuit excluding the output unit ( Figure 1 The connection circuit outside the relay output node combination (EB_C). In order to realize the status detection of the large circuit, this invention designs a status detection unit based on the original output control unit and output unit.

[0020] The large circuit status detection function is achieved by the combined action of the above three functional circuits. Its function is to monitor the conduction status of the braking output large circuit in real time and accurately identify whether there is a break point fault in the circuit.

[0021] During normal operation of the equipment (under normal working conditions without output braking), the output control unit periodically outputs detection control signals. These signals drive the status detection unit to detect the status of the braking output circuit and receive real-time circuit status information fed back by the status detection unit. This completes the abnormal determination of the braking output circuit status and realizes continuous monitoring of the status of the output circuit.

[0022] The state detection unit is the core of this invention, and its function is to realize the state detection and state feedback of the braking output circuit. Specifically, after receiving the periodic control signal from the output control unit, the state detection unit starts to detect the state of the braking output circuit and feeds back the detected state information to the output control unit.

[0023] To achieve safe and accurate detection of the braking output circuit status, the status detection unit in this invention adopts a differentiated heterogeneous design. It achieves dual detection of the braking output circuit status through two independent acquisition methods. The output control unit compares the acquisition results of the two heterogeneous circuits in a "two-out-of-two" manner. Only when both acquisition results are determined to be normal is the output circuit status confirmed to be normal; otherwise, it is determined to be abnormal.

[0024] The differentiated heterogeneous design employs two methods: Method 1 involves acquiring the output circuit current and determining if there are any abnormalities in the circuit state based on the magnitude of the current flowing through the circuit (e.g., whether it exceeds the normal current range, whether there is a current interruption, etc.). Method 2 involves acquiring the voltage at the output terminal of the output unit and determining if there are any abnormalities in the circuit state based on the actual voltage value at the output terminal. This differentiated heterogeneous design can avoid the common-factor effects caused by using the same acquisition circuit, improving the reliability and security of output circuit state acquisition.

[0025] The "middle loop" refers to the connection loop in the braking output circuit from the external braking power supply to the output terminal of the output unit. The middle loop status detection function is achieved by the joint operation of three functional circuits: the output control unit, the output unit, and the input acquisition unit. Its function is to detect the continuity status of the relay output node combination EB_C and its associated connections that are not covered by the large loop status detection, so as to identify whether there is a break fault in the relay output node combination EB_C and its associated connections.

[0026] During the braking test or braking output phase, the output control unit controls the emergency braking output, causing the relay output node combination (EB_C) to be in a closed state. The input acquisition unit collects the actual output state of the output unit to determine whether the output unit has normally output the emergency braking command, whether the actual output is consistent with the command requirements, and inversely determines whether there is any abnormality in the EB_C node itself, and whether there is a broken wire fault in the connection between the braking power input and EB_C, thus identifying potential fault hazards in advance.

[0027] The following section, with reference to the diagram, provides a detailed explanation of the method for detecting the status of the train's brake output circuit.

[0028] See Figure 1 The figure illustrates the distribution of breakpoints in the brake output circuit, the functional modules required for the support detection method, and the principle of brake output circuit state detection.

[0029] There are a total of four potential breakpoints in the braking output circuit, as shown in the diagram at locations A, B, C, and D. Segment A connects the locomotive braking power supply to the input terminal of the relay output node combination EB_C; segment B connects the relay output node combination EB_C and its connecting lines; segment C connects the output terminal of the relay output node combination EB_C to the intermediate loop status acquisition point; and segment D connects the intermediate loop status acquisition point to the braking equipment (i.e., the connection path from the status detection subsystem to the braking equipment). These four breakpoints cover all possible abnormal disconnection locations in the entire braking output circuit.

[0030] The output control unit, status detection unit, and output unit work together to realize the large-loop status detection function, namely, the detection of breakpoints at positions A, C, and D shown in the diagram. Among them, the status detection unit is the core component for realizing the large-loop status detection, realizing the status detection and feedback function of the braking output circuit, and is specifically composed of a detection control module, a current detection module, and a voltage detection module.

[0031] During normal operation (without braking output), the output relay is in an energized state, the equivalent node EB_C remains open, and the output control unit periodically checks the status of the braking output circuit. The output control unit CPU1 periodically outputs a detection enable signal CHK_EN, activating the current detection module and voltage detection module to operate effectively. The current detection module collects the channel current, and the voltage detection module collects the voltage at the EB_C output point. Both modules synchronously send the collected status data to CPU1 and CPU2 of the output control unit. The two CPUs of the control unit perform a "two-out-of-two" judgment on the collected current and voltage status data to determine whether the braking output circuit is normal. If only one status is found to be normal, the remaining combinations are judged as either a broken circuit in the braking output circuit or a malfunction in the status detection unit.

[0032] The status output of the status detection unit has four logical combinations [current & voltage]: 0&0, 0&1, 1&0, 1&1. Only when the status is 0&0 does it indicate that there is no break in the braking output circuit. Status 0&1 indicates that there is a break in the C segment or D segment. Status 1&0 indicates that there is a break in the A segment. Status 1&1 indicates that the status detection unit is abnormal.

[0033] The detection enable control signal CHK_EN, current detection, and voltage detection all adopt dynamic square wave form, which avoids the error of the return signal due to single point failure and improves the safety and reliability of the detection module status return.

[0034] The output control unit, input acquisition unit, and output unit work together to realize the mid-loop status detection function, namely the breakpoint detection at positions A, B, and C shown in the figure.

[0035] During the braking test or braking output phase, the output control unit outputs a braking command, the output unit relay switches to the de-energized state, the EB_C node closes, and the output unit outputs an energized braking signal. Input acquisition units CPU1 and CPU2 synchronously acquire the braking output status and perform a two-out-of-two comparison of the acquired results. If the output status acquired by the input acquisition units does not match the expectation, it indicates a break in line segment A, B, or C. Combined with the large circuit status detection results, it is possible to identify whether a break exists in line segment B, thus achieving comprehensive detection coverage of abnormalities in the relay output node combination EB_C and its associated connections.

[0036] Through the synergistic effect of the two detection mechanisms mentioned above, the status detection of the four segments A, B, C, and D is achieved, completing the status monitoring coverage of the entire braking output circuit.

[0037] join Figure 2The normally closed node EB_C described above is a schematic diagram of a relay output node combination. It is equivalent to a relay output combination structure used in energized braking equipment. Its core design consists of a series-parallel combination of normally closed nodes from relays A and B. It should be noted that the state of the normally closed node is defined as follows: when the relay coil is de-energized (not energized), the node remains in its initial closed state. The node only switches to the open state when the coil is energized.

[0038] The core technical advantage of this invention lies in:

[0039] The braking output circuit status detection method described in this invention can achieve real-time continuous monitoring of the braking output circuit status throughout the entire cycle from power-on to operation. Its core technological advantages are specifically reflected in the following four aspects: 1) Differentiated heterogeneous acquisition design to avoid common-cause faults. The braking output circuit status detection method adopts a differentiated heterogeneous current and voltage acquisition circuit design. The two acquisition circuits are independently deployed and have different structures, effectively avoiding common-cause faults such as synchronous failures caused by extreme environments (e.g., high temperature, strong vibration) in traditional identical circuit designs, significantly improving the reliability and safety of the system under complex operating conditions; 2) Dynamic square wave signal design to reduce the false judgment rate of single-point faults. The detection enable signal and current and voltage acquisition signals are all transmitted in the form of dynamic square waves. Compared with static signals, dynamic square waves can effectively identify and eliminate signal distortion problems caused by single-point faults (e.g., instantaneous short circuits, poor contact), greatly reducing the probability of false judgments and further improving the reliability of status detection; 3) Status combination judgment to achieve accurate fault location. The detection circuit, through a combination of current and voltage detection, can accurately identify the location of the brake output circuit break and the abnormality of the detection module itself, solving the pain point of "knowing the fault but not the location" in detection; 4) Full-cycle monitoring coverage, meeting the needs of all operating scenarios. Breaking through the limitations of traditional systems that only detect during the startup phase, it realizes full-cycle monitoring of the brake output circuit status. From the startup braking test before train start-up, to real-time monitoring during operation, and then to the status verification after stopping, it comprehensively covers the entire train operation cycle, effectively making up for the shortcomings of traditional systems "lacking real-time detection during operation", meeting the railway train's need for continuous safety monitoring of the energized braking system, and providing all-time protection for train operation safety.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting the state of a train brake output circuit, characterized in that, The braking output circuit refers to the entire connection circuit from the external braking power supply to the braking device; a status detection subsystem is designed in the braking output circuit, which includes an output control unit, an input acquisition unit, an output unit, and a status detection unit; the status detection subsystem adopts a dual-machine hot standby redundancy architecture, and each functional unit is configured with a dual-machine operation mode of machine A and machine B. The output control unit and the input acquisition unit both adopt a "two-out-of-two" architecture composed of two processors with the same function. The detection methods are large circuit state detection and medium circuit state detection, respectively, to achieve detection coverage of the entire braking output circuit state; the large circuit refers to the connection circuit in the braking output circuit excluding the output unit, and the medium circuit refers to the connection circuit in the braking output circuit from the external braking power supply to the output end of the output unit. After receiving the periodic control signal from the output control unit, the status detection unit starts detecting the status of the braking output circuit and feeds back the detected status information to the output control unit. The detection method enables real-time continuous monitoring of the status of the braking output circuit throughout the entire cycle from powering on the braking device to the post-stop verification.

2. The detection method according to claim 1, characterized in that, The circuit state refers to the connection state of the brake output circuit; the brake device refers to the energized brake device.

3. The detection method according to claim 1, characterized in that, The status detection unit adopts a differentiated heterogeneous design and achieves dual detection of the brake output circuit status through two independent acquisition methods. The output control unit performs a "two-out-of-two" comparison on the acquisition results of the two heterogeneous circuits. Only when both acquisition results are judged to be normal is the output circuit status confirmed to be normal; otherwise, it is judged to be abnormal.

4. The detection method according to claim 3, characterized in that, The differentiated heterogeneous design, in one method, involves collecting the output circuit current and determining whether there is an abnormality in the circuit state based on the magnitude of the current flowing through the circuit. The second method involves collecting the voltage at the output terminal of the output unit and determining whether there is an abnormality in the circuit state based on the actual voltage value at the output terminal. The differentiated heterogeneous design can avoid the common factor effects caused by using the same acquisition circuit.

5. The detection method according to claim 1, characterized in that, The detection enable signal and the current and voltage acquisition signals are all transmitted in the form of dynamic square waves, which can effectively identify and eliminate signal distortion caused by single-point faults and reduce the probability of misjudgment of detection results.

6. The detection method according to claim 1, characterized in that, The large circuit status detection is jointly implemented by three functional circuits: output control unit, output unit, and status detection unit. It monitors the conduction status of the braking output large circuit in real time and accurately identifies whether there is a breakpoint fault in the large circuit. During normal operation of the equipment after power-on, the output control unit periodically outputs detection control signals. These signals drive the status detection unit to detect the status of the braking output circuit and receive real-time circuit status information from the status detection unit. This completes the abnormal determination of the braking output circuit status and enables continuous monitoring of the status of the large output circuit.

7. The detection method according to claim 1, characterized in that, The intermediate loop status detection is jointly implemented by three functional circuits: the output control unit, the output unit, and the input acquisition unit. It is used to detect the continuity status of the relay output node combination EB_C and its associated wiring that are not covered by the large loop status detection, so as to identify whether there is a break fault in the relay output node combination EB_C and its associated wiring.

8. The detection method according to claim 7, characterized in that, During the braking test or braking output phase, the output control unit controls the emergency braking output, causing the relay output node combination (EB_C) to be in a closed state. The input acquisition unit collects the actual output state of the output unit to determine whether the output unit has normally output the emergency braking command, whether the actual output is consistent with the command requirements, and inversely determines whether there is any abnormality in the EB_C node itself, and whether there is a broken wire fault in the connection between the braking power input and EB_C, thus identifying potential fault hazards in advance.

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