Track loop monitoring device

Abstract

The present invention provides a track circuit monitoring device capable of determining the degree of distortion in the voltage waveform of the track voltage in a track circuit. [Solution] The track circuit monitoring device 1 is characterized by comprising: a track voltage acquisition unit 1A; a local voltage acquisition unit 1B; a phase difference calculation unit 1C; a state recognition unit 1D; an information generation unit 1F; and a storage unit 1G that stores state information and stores at least the track voltage V111 among the track voltage acquisition unit 1A, the local voltage V121 acquired by the local voltage acquisition unit 1B, and the phase difference calculated by the phase difference calculation unit 1C, in an acquisition result storage area 1G-2 different from the information storage area 1G-1.

Description

Technical Field

[0001] The present invention relates to a track circuit monitoring device for monitoring a track circuit for detecting an on-track state in a railway.

Background Art

[0002] Conventionally, a track circuit for detecting an on-track state in a railway has been provided. In such a track circuit, the on-track state is detected for each section of a railway rail electrically divided into a plurality of sections. The detection of the on-track state utilizes a configuration in which when a train is present, the sectional rail of each section is electrically short-circuited via the axle of the train, and is performed based on voltage measurement of the sectional rail or the like. By detecting the on-track state by the track circuit, operations such as controlling the operation of trains so that, for example, only one train is present in each section become possible, and situations such as multiple trains approaching each other too closely during travel can be effectively avoided.}

[0003] Here, a track circuit monitoring device for monitoring whether such a track circuit is operating normally is known (see, for example, Patent Document 1). In the device described in Patent Document 1, an alternating voltage is applied to the sectional rail in the track circuit, and an alternating voltage is also applied to a local distribution line installed near the sectional rail. Then, the track circuit is monitored based on various parameters including the track voltage of the sectional rail, the local voltage of the local distribution line, and the phase difference between the two in these applied states. As a monitoring result, information including the on-track state, the amplitude values of the track voltage and the local voltage, and the phase difference, etc. is generated and output as appropriate according to requests from external devices.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, in track circuits, for example, to avoid interference with the overhead line voltage for pantographs, an AC voltage shifted by dividing the frequency from the commercial frequency is sometimes applied to the section rails, and then the frequency is doubled by the track circuit monitoring device to return it to the original commercial frequency. The voltage waveform of the track voltage acquired by the track circuit monitoring device after frequency division and doubling may be distorted, and if such distortion is large, it may reduce the monitoring accuracy of the track circuit monitoring device. On the other hand, currently it is not possible to determine the degree of distortion in the track voltage from the information output from the track circuit monitoring device, making it difficult to contribute to measures to improve monitoring accuracy.

[0006] Accordingly, the present invention aims to provide a track circuit monitoring device that can determine the degree of distortion of the voltage waveform of the track voltage in a track circuit, taking into account the circumstances described above. [Means for solving the problem]

[0007] To solve the above problems, the track circuit monitoring device monitors the state of a track circuit for detecting the presence of a train in a section of a railway rail that is electrically divided into multiple sections, based on the voltage of the section rail to which a first AC voltage is applied and which is electrically short-circuited when a train is present, and the voltage of a local power distribution line installed near the section rail to which a second AC voltage is applied, and the state of the track circuit, comprising: a track voltage acquisition unit that acquires the track voltage used for detecting the presence of a train at a predetermined sampling interval based on the voltage of the section rail; and a local voltage that acquires the local voltage used for detecting the presence of a train at the sampling interval based on the voltage of the local power distribution line. The device is characterized by comprising: a voltage acquisition unit; a phase difference calculation unit that calculates the phase difference between the track voltage and the local voltage; a state recognition unit that grasps the occupancy status in the section based on the track voltage and the phase difference; an information generation unit that generates state information representing the state of the track circuit based on the track voltage, the local voltage, the phase difference, and the occupancy status; and a storage unit that stores the state information and stores at least the track voltage among the track voltage acquired by the track voltage acquisition unit, the local voltage acquired by the local voltage acquisition unit, and the phase difference calculated by the phase difference calculation unit during a predetermined acquisition period in an acquisition result storage area different from the information storage area in which the state information is stored.

[0008] According to the above-described track circuit monitoring device, at least the track voltage among the track voltage, local voltage, and phase difference acquired during a predetermined acquisition period is stored in the acquisition result storage area of ​​the storage unit as a storage target. Since the track voltage acquired at sampling intervals during the acquisition period represents the voltage waveform of this track voltage, if distortion occurs in the voltage waveform of the track voltage in the track circuit, the degree of distortion of the voltage waveform can be determined from the track voltage stored as a storage target in the acquisition result storage area.

[0009] In this case, it is preferable for the storage unit to store the storage target as the acquisition period, which is the period from the start timing after the occurrence of the change in the occupancy status grasped by the status grasping unit.

[0010] With this configuration, the track voltage is stored from the start timing after the occurrence of a change in the track occupancy status, which is likely to cause distortion in the track voltage waveform. Therefore, the degree of distortion in the track voltage waveform can be determined more effectively.

[0011] Furthermore, the presence status of each section has three states: presence (the train is present in the section), forward presence (the train has moved to a section ahead of the section in the direction of travel of the train as viewed from the section), and non-presence (the train has also moved from the forward section). The acquisition result storage area in the storage unit is divided into the presence, forward presence, and non-presence categories, and it is preferable that the storage target is stored in the area corresponding to the presence status when the storage target was obtained.

[0012] In this configuration, the data to be stored is located in one of three regions, each divided into "occupied," "forward occupied," and "unoccupied," corresponding to the occupancy state at the time the data was obtained. This allows for analysis of the distortion of the track voltage waveform for each of the three occupancy states, enabling a detailed determination of the degree of distortion in the track voltage waveform for each occupancy state.

[0013] Furthermore, the memory unit also stores the phase difference, and it is preferable that the phase difference is not stored if the presence status at the time the phase difference is calculated is the presence status, but is stored in the area corresponding to the presence status when the presence status is the forward presence status or the absence status.

[0014] With this configuration, when phase difference is the target of storage, the phase difference is not stored when the value is zero (i.e., when the train is present), but the phase difference is stored for forward-facing trains and non-trains, which are useful for analysis and have a value. This allows for efficient storage of phase differences while reducing the amount of memory used.

[0015] Furthermore, the system includes a period setting unit that sets an unstable period during which the track voltage becomes unstable due to a change in the track occupancy status, based on the timing of the occurrence of a change in the track occupancy status as determined by the status recognition unit. The information generation unit generates the status information based on the track voltage and local voltage acquired during the period excluding the unstable period set by the period setting unit, the phase difference calculated using the track voltage and local voltage, and the track occupancy status determined using the track voltage and phase difference. The storage unit preferably stores the storage target as the acquisition period, which is the period from the start timing corresponding to the end of the unstable period.

[0016] This configuration allows for obtaining highly accurate state information based on stable orbital voltages, local voltages, and phase differences calculated from these voltages, which are acquired during periods excluding unstable periods. Furthermore, by setting the start timing of memory to coincide with the end of the unstable period, it is possible to store data in a stable state, thereby enabling highly accurate determination of the degree of voltage waveform distortion in the orbital voltage.

[0017] Furthermore, if a new state change in the track occupancy status occurs during the unstable period set by the period setting unit, the unstable period is extended based on the time of occurrence of the new state change, and a signal abnormality in the track circuit is detected based on a comparison of the elapsed time since the first state change occurred in the extended unstable period with a predetermined timeout threshold. When the signal abnormality is detected by the period setting unit, it is preferable for the storage unit to store the data to be stored during the signal abnormality acquisition period corresponding to the detection timing in a signal abnormality storage area that is different from the acquisition result storage area.

[0018] This configuration effectively detects signal anomalies where rapid state changes exceed the timeout threshold, and also stores the data associated with such anomalies separately. This allows for an effective determination of the degree of distortion in the voltage waveform of the orbital voltage at the time of the signal anomaly.

[0019] Furthermore, it is preferable that the first AC voltage and the second AC voltage are AC voltages having one period selected from a predetermined number of periods, the storage unit stores the data to be stored with the acquisition period being an integer multiple of the least common multiple of the multiple periods, and the sampling interval in the orbital voltage acquisition unit and the local voltage acquisition unit is a time interval of 1 / 10 or less of the one period.

[0020] With this configuration, regardless of which of the above multiple periods the first and second AC voltages are on, by setting the acquisition period to an integer multiple of the least common multiple of the multiple periods, it is possible to store orbital voltages of a sufficient length for determining distortion of the voltage waveform. Furthermore, by setting the sampling interval in the orbital voltage acquisition unit and the local voltage acquisition unit to 1 / 10 or less of one of the above periods, i.e., the periods of the first and second AC voltages, it is possible to store orbital voltages with sufficient resolution for checking the voltage waveform while keeping the amount of data stored in the storage unit to a minimum.

[0021] Furthermore, it is preferable to further include an output unit that reads and outputs the contents of the storage unit when a predetermined output timing arrives, or in response to a request from outside the device.

[0022] This configuration allows for easier retrieval of stored data compared to, for example, a configuration where the memory unit stores data in a portable memory device, and a worker retrieves the portable memory device during maintenance. [Effects of the Invention]

[0023] According to the above track circuit monitoring device, it is possible to determine the degree of distortion of the voltage waveform of the track voltage in the track circuit.

Brief Description of the Drawings

[0024] [Figure 1] It is a schematic configuration diagram showing an example of a track circuit that is a monitoring target in an embodiment of the track circuit monitoring device. [Figure 2] It is a schematic configuration diagram showing the track circuit monitoring device shown in FIG. 1. [Figure 3] It is a schematic diagram showing the functional blocks of the track circuit monitoring device shown in FIG. 1. [Figure 4] It is a schematic flowchart showing the flow of processing from the acquisition of the track voltage and local voltage in the track circuit monitoring device shown in FIGS. 1 to 3 to the storage in the storage unit. [Figure 5] It is a schematic diagram showing the state in which the phase difference is calculated in the phase difference calculation process shown in FIG. 4. [Figure 6] It is a time chart showing an example of the time change of the occupancy state in a section of the track circuit shown in FIGS. 1 to 3 and the accompanying time changes in the track voltage, local voltage, and phase difference. [Figure 7] It is a schematic diagram showing the state in which an unstable period is set in the period setting process shown in FIG. 4. [Figure 8] It is a schematic diagram showing the state in which an unstable period is set when the instantaneous change of the amplitude of the track voltage to "0" is repeated a plurality of times. [Figure 9] It is a diagram showing how the state information of the track circuit is generated by the processing represented by the flowchart of FIG. 4 according to the time chart shown in FIG. 6. [Figure 10] It is a schematic diagram showing how various information is stored in the storage unit by the processing represented by the flowchart of FIG. 4. [Figure 11] It is a schematic flowchart showing the flow of processing in which the output unit shown in FIG. 3 outputs the stored content of the storage unit. [Modes for carrying out the invention]

[0025] An embodiment of the track circuit monitoring device will be described below with reference to the drawings.

[0026] Figure 1 is a schematic diagram showing an example of a track circuit that is monitored by one embodiment of the track circuit monitoring device.

[0027] The track circuit L1 shown in Figure 1 is a circuit including a railway rail L1a for detecting the presence of a train on a railway line. The railway rail L1a is divided into a station section A2 that passes through station ST1 and a block section A1 sandwiched between station sections A2. A signal SG1 is installed at the boundary between station section A2 and block section A1. Block section A1 is further divided into multiple sections A11. Each section A11 is provided with a section rail L11, and adjacent sections A11 are electrically separated from each other by the section rails L11. A first AC voltage of 2V to 3V at commercial frequency is applied to the section rail L11 of each section A11 from a first power supply E11. When a train is present in section A11, the section rail L11 is electrically short-circuited by the train's axle, and the voltage of that section rail L11 becomes "0".

[0028] On the other hand, a local power distribution line L12 is installed near the section rail L11, to which a second AC voltage of 100V to 120V at the same commercial frequency as the first AC voltage is applied from a second power supply E12. Furthermore, the section rail L11 is connected to the track coil L131 of the track relay L13 for detecting the presence of a train, and the local power distribution line L12 is connected to the local coil L132 of this track relay L13.

[0029] In track circuit L1, the presence of a train in section A11 is detected when the voltage of section rail L11 becomes "0" and track relay L13 operates. Track circuit L1 also determines the phase difference between the voltages of track coil L131 and local coil L132. If the voltage of section rail L11 is not "0" and track coil L131 is lagging in phase with local coil L132, it is detected that there is no train in section A11, but there is a train in section A11 ahead in the direction of travel. Conversely, if the voltage of section rail L11 is not "0" and track coil L131 is leading in phase with local coil L132, it is detected that there is no train in either section A11 or section A11 ahead in the direction of travel.

[0030] The track circuit monitoring device 1 receives the voltages of the track coil L131 and the local coil L132, that is, the voltage V11 of the section rail L11 and the voltage V12 of the local power distribution line L12, and monitors the track circuit L1 based on these voltages V11 and V12.

[0031] Figure 2 is a schematic diagram showing the track circuit monitoring device shown in Figure 1.

[0032] The track circuit monitoring device 1 is a device that monitors the track circuit L1 shown in Figure 1, and comprises a track voltage processing unit 11, a local voltage processing unit 12, an MPU 13, an RS485 transmission unit 14, a power supply unit 15, an oscillator 16, and a reset IC 17.

[0033] The track voltage processing unit 11 receives the voltage V11 of the section rail L11 shown in Figure 1 and performs signal processing on the said voltage V11.

[0034] The track voltage processing unit 11 includes a track step-down circuit 111, a track isolation amplifier 112, a first track LPF 113, a first track HPF 114, a second track LPF 115, a second track HPF 116, and a track inverting amplifier 117. The track step-down circuit 111 is a circuit that steps down the input section rail voltage V11 to 0.99 times its original value. The track isolation amplifier 112 is a circuit that transmits the stepped-down voltage to the subsequent stage while electrically isolating it from the track step-down circuit 111. In addition, this track isolation amplifier 112 adds a predetermined DC offset to the input voltage. This DC offset is adjusted to an offset value such that the track voltage V111 finally obtained by the track voltage processing unit 11 is always a positive value. The first orbital LPF113 is a low-pass filter that allows input voltages below a predetermined frequency (e.g., 219 Hz) to pass through. The first orbital HPF114, located downstream of the first orbital LPF113, is a high-pass filter that allows input voltages above a predetermined frequency (e.g., 9.95 Hz) to pass through.

[0035] Furthermore, the orbital voltage processing unit 11 is provided with two routes for transmitting the orbital voltage V111 to the MPU 13. One route transmits the orbital voltage V111 obtained via the second orbital LPF 115, the second orbital HPF 116, and the orbital inverting amplifier 117 to the MPU 13. The other route transmits the orbital voltage V111 obtained only via the orbital inverting amplifier 117 to the MPU 13. The second orbital LPF 115 is a low-pass filter that allows input voltages below a predetermined frequency (e.g., 66.32 Hz) to pass through. The second orbital HPF 116 is a high-pass filter that allows input voltages above a predetermined frequency (e.g., 33.66 Hz) to pass through. The orbital inverting amplifier 117 is provided at the final stage of each of the two routes described above and is an inverting amplifier circuit that amplifies the input voltage by a predetermined number (e.g., 5 times) to obtain the orbital voltage V111 and transmits it to the MPU 13.

[0036] The local voltage processing unit 12 receives the voltage V12 of the local power distribution line L12 shown in Figure 1 and performs signal processing on the said voltage V12.

[0037] The local voltage processing unit 12 includes a local step-down circuit 121, a local isolation amplifier 122, a local low-pass filter 123, a local high-pass filter 124, and a local inverting amplifier 125. The local step-down circuit 121 is a circuit that steps down the voltage V12 of the input local distribution line L12 to 0.06 times its original value. The local isolation amplifier 122 is a circuit that transmits the stepped-down voltage to the subsequent stage while electrically isolating it from the local step-down circuit 121. This local isolation amplifier 122 also adds a predetermined DC offset to the input voltage. This DC offset is adjusted to an offset value such that the local voltage V121 finally obtained by the local voltage processing unit 12 is always a positive value. The local low-pass filter 123 is a low-pass filter that allows the input voltage to pass through frequencies below a predetermined frequency (e.g., 219 Hz). The local HPF124, located downstream of the local LPF123, is a high-pass filter that allows input voltages above a predetermined frequency (e.g., 9.95 Hz) to pass through. The local inverting amplifier125 is located at the final stage of the local voltage processing unit12 and is an inverting amplifier circuit that amplifies the input voltage by a predetermined number (e.g., 0.75 times) to obtain the local voltage V121, which is then transmitted to the MPU13.

[0038] The MPU13 is a microprocessor equipped with a CPU (Central Processing Unit), etc. The MPU13 executes various operations, as described later, using programs stored in its internal memory. The MPU13 also includes AD converters 131, 132, and 133, and UARTs 134 and 135.

[0039] AD converter 131 receives an AC waveform with a DC offset of the local voltage V121 from the local inverting amplifier 125 in the local voltage processing unit 12, and converts the analog signal into a digital signal. AD converter 132 receives an AC waveform with a DC offset of the orbital voltage V111 from a route that passes only through the orbital inverting amplifier 117 in the orbital voltage processing unit 11, and converts the analog signal into a digital signal. AD converter 133 receives an AC waveform with a DC offset of the orbital voltage V111 from a route that passes through the second orbital LPF 115, the second orbital HPF 116, and the orbital inverting amplifier 117 in the orbital voltage processing unit 11. AD converter 133 converts the analog signal of the AC waveform thus input into a digital signal.

[0040] UART134 is an interface circuit that converts parallel data to be transmitted to the RS485 transmission unit 14 into serial data, and converts serial data received from the RS485 transmission unit 14 into parallel data. UART134 outputs state information representing the state of the track circuit L1 calculated by the MPU 13 as serial data. In addition, UART134 receives various instruction signals related to the monitoring of the track circuit L1 received by the RS485 transmission unit 14 and outputs them to the MPU 13 as parallel data. UART135 converts parallel data into serial data for serial communication with the PC3 used for various settings. It also converts serial data received from the PC3 into parallel data.

[0041] The RS485 transmission unit 14 outputs information received from the UART 134 to the external device 2. The RS485 transmission unit 14 also outputs various instruction signals received from the external device 2 to the UART 134. In this embodiment, communication between the track circuit monitoring device 1 and the external device 2 is performed using the RS485 standard, but other communication standards, whether wired or wireless, may be used instead.

[0042] The power supply unit 15 converts the power supplied from the power supply 4 into the voltage and other values ​​required by each block of the track circuit monitoring device 1 and supplies them to the device.

[0043] The oscillator 16 is composed of, for example, a crystal oscillator and generates a clock signal for the operation of the MPU 13.

[0044] The reset IC17 is a well-known circuit that monitors when the output voltage of power supply 4 exceeds the operating voltage of MPU13 and activates MPU13 by releasing the reset signal to MPU13.

[0045] External device 2 receives information output by the track circuit monitoring device 1. External device 2 comprises an RS485 transmission unit 21 and a microcontroller circuit 22. The RS485 transmission unit 21 receives information output from the track circuit monitoring device 1. The microcontroller circuit 22 includes a microprocessor and the like, and performs processing based on the information received from the track circuit monitoring device 1, such as internal storage or transmission to a monitoring center.

[0046] PC3 is a computer that serves as a terminal for various settings of the track circuit monitoring device 1. PC3 is connected when necessary for settings and other operations. Power supply 4 supplies power (e.g., 5V DC) to the track circuit monitoring device 1.

[0047] In this embodiment, the following functional blocks are constructed in the track circuit monitoring device 1 described above.

[0048] Figure 3 is a schematic diagram showing the functional blocks of the track circuit monitoring device shown in Figure 1.

[0049] The track circuit monitoring device 1 of this embodiment includes a track voltage acquisition unit 1A, a local voltage acquisition unit 1B, a phase difference calculation unit 1C, a status recognition unit 1D, a period setting unit 1E, an information generation unit 1F, a storage unit 1G, and an output unit 1H.

[0050] The track voltage acquisition unit 1A is a functional block constructed by the track voltage processing unit 11 and the AD converters 132 and 133 of the MPU 13. The track voltage acquisition unit 1A acquires the track voltage V111 based on the voltage V11 of the section rail L11. The track voltage acquisition unit 1A acquires the track voltage V111 after adding a DC offset, amplifying it, and further converting it to a digital value.

[0051] The local voltage acquisition unit 1B is a functional block constructed by the local voltage processing unit 12 and the AD converter 131 of the MPU 13. The local voltage acquisition unit 1B acquires the local voltage V121 based on the voltage V12 of the local power distribution line L12. The local voltage acquisition unit 1B also acquires the local voltage V121 after adding a DC offset, amplifying it, and further converting it to a digital value.

[0052] In this embodiment, as described above, a first AC voltage of commercial frequency is applied to the section rail L11 from the first power supply E11. A second AC voltage of the same commercial frequency as the first AC voltage is applied to the local distribution line L12 from the second power supply E12. The period of the first and second AC voltages is selected from the periods of 1 / 50 second and 1 / 60 second, which are the periods of two types of commercial power supplies in Japan. At this time, the track voltage acquisition unit 1A and the local voltage acquisition unit 1B acquire the track voltage V111 and local voltage V121 with the following sampling intervals. That is, the track voltage acquisition unit 1A and the local voltage acquisition unit 1B acquire the track voltage V111 and local voltage V121 with a sampling interval of 1 / 10 or less of the period of the first and second AC voltages selected as described above. If the AC voltage period is 1 / 50 second, the sampling interval is set to 2 milliseconds or less; if the period is 1 / 60 second, the sampling interval is set to 1.7 milliseconds or less. Here, the sampling interval is set to 0.5 milliseconds, which applies to both cases above. The track voltage acquisition unit 1A and the local voltage acquisition unit 1B acquire the track voltage V111 and local voltage V121, respectively, at a sampling interval of 0.5 milliseconds. By sequentially acquiring the target voltage at this sampling interval, the target voltage waveform is obtained. Here, the sampling period is set to 0.5 milliseconds, but this is appropriately selected based on the capabilities of the MPU used, the required measurement accuracy, and especially the local crossover time, track crossover time, and the frequency of the input AC voltage for the phase difference calculation described later. By using a shorter sampling period, the resolution can be further increased, but the MPU, AD converter, etc. used must be suitable for high-speed operation, and the setting is determined based on measurement accuracy, cost-effectiveness, etc.

[0053] The phase difference calculation unit 1C is a functional block constructed by the operation of the MPU 13, and it calculates the phase difference between the orbital voltage V111 and the local voltage V121. This phase difference calculation is performed repeatedly at the following calculation interval once acquisition by the orbital voltage acquisition unit 1A and the local voltage acquisition unit 1B has started. In this embodiment, 100 milliseconds is used as the calculation interval, which is an integer multiple (here, 1) of 100 milliseconds, the least common multiple of the 1 / 50 second period and the 1 / 60 second period. During the 100 millisecond calculation interval, the phase difference is calculated based on the time difference of the intersection time with the midpoint voltage (e.g., the median of the amplitude) of the AC voltage waveform drawn by each of the orbital voltage V111 and local voltage V121, which are obtained 200 times each at a sampling interval of 0.5 milliseconds. In other words, in the phase difference calculation unit 1C, the phase difference is repeatedly calculated at a calculation interval of 100 milliseconds after acquisition has started by the orbital voltage acquisition unit 1A and the local voltage acquisition unit 1B.

[0054] The status recognition unit 1D is a functional block constructed by the operation of the MPU 13, and it recognizes the occupancy status in section A11 based on the track voltage V111 and the phase difference described above.

[0055] The period setting unit 1E is a functional block constructed by the operation of the MPU 13, and sets an unstable period in which the track voltage V111 becomes unstable due to a change in the track occupancy status, based on the timing of the change in status in the track occupancy status as determined by the status recognition unit 1D. Furthermore, if a new change in the track occupancy status occurs during the unstable period that has been set, the period setting unit 1E extends the unstable period based on the timing of the occurrence of the new change in status. Then, the period setting unit 1E detects the occurrence of a signal abnormality in the track circuit L1 based on a comparison of the elapsed time since the first change in track occupancy occurred in the extended unstable period with a predetermined timeout threshold.

[0056] The information generation unit 1F is a functional block constructed by the operation of the MPU 13. This information generation unit 1F generates state information representing the state of the track circuit L1 based on the track voltage V111, local voltage V121, phase difference, and occupancy status. In this embodiment, the information generation unit 1F generates state information based on the track voltage V111, local voltage V121 acquired during the period excluding the unstable period, the phase difference calculated from these voltages, and the occupancy status which is also determined using the phase difference. This state information generation is repeated at the following generation interval. In this embodiment, 100 milliseconds, which is an integer multiple (here 1x) of the same 100 milliseconds as the phase difference calculation interval in the phase difference calculation unit 1C, is adopted as this generation interval.

[0057] The information generation unit 1F calculates orbital voltage amplitude values ​​and local voltage amplitude values, which are the amplitude values ​​of the AC voltage waveforms drawn by the orbital voltage V111 and local voltage V121, obtained 200 times at a sampling interval of 0.5 ms over a 100 m s interval and used in the phase difference calculation unit 1C to calculate the phase difference. The information generation unit 1F also performs an anomaly determination on these orbital voltage amplitude values ​​and local voltage amplitude values, as well as on the phase difference calculated based on the same orbital voltage V111 and local voltage V121 over the same 100 m s interval. This anomaly determination is separate from the detection of signal anomalies by the period setting unit 1E, and is performed on the orbital voltage amplitude values, local voltage amplitude values, and phase difference that are repeatedly obtained at 100 m s intervals after the unstable period has ended without the detection of signal anomalies. In the anomaly determination, the orbital voltage amplitude values, local voltage amplitude values, and phase difference calculated after the end of the unstable period are compared with a threshold value corresponding to the occupancy status at the time of calculation. Then, if the judgment condition based on this threshold is satisfied, it is determined that there is no abnormality, and if the judgment condition is not satisfied, it is determined that there is an abnormality. The information generation unit 1F then generates status information, including the occupancy status, track voltage amplitude value, local voltage amplitude value, phase difference, and judgment results regarding abnormalities in the track circuit L1, at generation intervals of 100 milliseconds.

[0058] The memory unit 1G first stores the state information generated by the information generation unit 1F in the information storage area 1G-1. This state information is stored by updating the contents of the information storage area 1G-1 at a 100ms update interval using the state information repeatedly generated by the information generation unit 1F at a 100ms generation interval.

[0059] Furthermore, the memory unit 1G stores data to be stored that includes at least the track voltage V111 acquired by the track voltage acquisition unit 1A during the following acquisition period. Specifically, the track voltage V111 during the acquisition period, the local voltage V121 during the acquisition period, and the phase difference calculated based on them are stored as data to be stored. The acquisition period here is a certain period of time from the start timing after the occurrence of a change in the occupancy status as grasped by the status grasping unit 1D. This certain period is set to 100 milliseconds, which is an integer multiple (in this case, 1) of the same 100 milliseconds used for the calculation interval of the phase difference in the phase difference calculation unit 1C and the generation interval of the status information in the information generation unit 1F. In this embodiment, the start timing of this 100 millisecond acquisition period is set to the end of the unstable period set by the period setting unit 1E according to the change in the occupancy status. The memory unit 1G stores 200 orbital voltages V111 and local voltages V121 acquired at 0.5 m-second sampling intervals during the 100 m-second acquisition period from the end of this point, as well as the phase difference calculated based on them. This storage is performed in the acquisition result storage area 1G-2, which is different from the information storage area 1G-1 where state information is stored. Furthermore, this storage in the acquisition result storage area 1G-2 is divided into three types of states: present, forward present, and absent. Storage for each state is performed by updating the stored contents of each category each time a state change to the same state occurs. In other words, each of the three types of state categories stores the orbital voltage V111, local voltage V121, and phase difference at the time the state change to that state last occurred.

[0060] Furthermore, in addition to storing data in the acquisition result storage area 1G-2, when the period setting unit 1E detects the aforementioned signal anomaly, the storage unit 1G stores the orbital voltage V111 and local voltage V121 obtained during a predetermined acquisition period from the detection timing, and the phase difference θ calculated based on them, as storage targets. This storage is performed in the signal anomaly storage area 1G-3, which is different from the acquisition result storage area 1G-2. This storage in the signal anomaly storage area 1G-3 is also performed on storage targets that include at least the orbital voltage V111 acquired during an acquisition period of 100 m seconds, which is an integer multiple (in this case, 1) of 100 m seconds, the same as the storage in the acquisition result storage area 1G-2. In other words, in this embodiment, the signal anomaly storage area 1G-3 stores storage targets that include at least 200 orbital voltage V111 acquired at a sampling interval of 0.5 m seconds during an acquisition period of 100 m seconds from the timing of signal anomaly detection by the period setting unit 1E. The storage of this signal anomaly in the signal anomaly storage area 1G-3 is performed by updating the stored contents each time a signal anomaly is detected in the period setting unit 1E.

[0061] Finally, the output unit 1H is a functional block constructed by the UART 134 and RS485 transmission unit 14 in the MPU 13, and reads and outputs the contents stored in the memory unit 1G. In this embodiment, the output by the output unit 1H is performed when a predetermined output timing arrives, or in response to a request from outside the device. Requests from outside the device may be made from a monitoring center via external equipment 2, or from a worker's PC 3 connected to the track circuit monitoring device 1. In response to such requests from outside the device, the output unit 1H outputs the requested contents to the requester.

[0062] Next, the operation of the track circuit monitoring device 1 with the above configuration will be explained with reference to Figures 4 to 10.

[0063] Figure 4 is a schematic flowchart illustrating the processing flow from the acquisition of track voltage and local voltage in the track circuit monitoring device shown in Figures 1 to 3 to their storage in the memory unit.

[0064] When the power is turned on and the track circuit monitoring device 1 starts up, the track voltage acquisition unit 1A and the local voltage acquisition unit 1B first perform acquisition processing S11. In acquisition processing S11, 200 values ​​each of track voltage V111 and local voltage V121 are acquired over 100 milliseconds at a sampling interval of 0.5 milliseconds. Here, 5 waveforms of track voltage V111 and local voltage V121 are acquired in 50Hz regions, and 6 waveforms in 60Hz regions. As a result, each voltage is obtained without any peaks or gaps in the AC waveforms drawn by the 200 track voltages V111 and local voltage V121, and the influence of regional frequency differences in subsequent calculations of phase differences can be excluded.

[0065] Next, the phase difference calculation unit 1C executes a phase difference calculation process S12 to calculate the phase difference between the orbital voltages V111 and local voltages V121, which have been acquired in sets of 200. In the phase difference calculation process S12, the phase difference is calculated as follows.

[0066] Figure 5 is a schematic diagram showing how the phase difference is calculated in the phase difference calculation process shown in Figure 4.

[0067] Figure 5 shows the line GL1 drawn by the AC waveform of the orbital voltage V111, acquired at 0.5 m-second intervals over 100 m-seconds, along with the midpoint voltage V112 of the voltage change (for example, the median value of the amplitude of the orbital voltage V111). Similarly, for the local voltage V121, the line GL2 drawn by the AC waveform of the local voltage V121, acquired at 0.5 m-second intervals over the same 100 m-second period, is also shown, along with the midpoint voltage V122 of the voltage change (for example, the median value of the amplitude of the local voltage V121). In this embodiment, the phase difference is calculated as follows.

[0068] First, the local crossing time TC2 is determined when the line GL2 of the AC waveform of the local voltage V121 intersects with the midpoint voltage V122. This local crossing time TC2 is calculated by a linear interpolation method using a pair of voltages V123 obtained by sequentially acquiring the local voltages V121 in the local voltage acquisition unit 1B, with the midpoint voltage V122 sandwiched between them.

[0069] Furthermore, the track crossing time TC1, at which the line GL1 of the AC waveform of the track voltage V111 intersects with the midpoint voltage V112, can be determined. This track crossing time TC1 is calculated by a linear interpolation method using a pair of voltages V113 obtained by sandwiching the midpoint voltage V112 between the track voltages V111 sequentially acquired by the track voltage acquisition unit 1A, as follows. The pair of voltages V113 referred to here are a pair of voltages obtained by sandwiching the midpoint voltage V112 between them in the same direction as the increase or decrease of the local voltage V121 at the local crossing time TC2.

[0070] In the phase difference calculation process S12 shown in Figure 4, once the track crossing time TC1 and local crossing time TC2 are determined in this manner, the time difference Δt between the track crossing time TC1 and the local crossing time TC2 is calculated. Then, based on the time difference Δt between the track crossing time TC1 and the local crossing time TC2 and the period T of the local voltage V121, the phase difference θ is calculated using the formula θ = (360 / T) × Δt. When the calculated θ has a negative sign, it is a lagging phase corresponding to a train being ahead, and when it has a positive sign, it is a leading phase corresponding to a train not being present. Also, when a train is present, the track voltage V111 becomes "0", so the phase difference cannot be calculated, and in this case, the phase difference θ is set to "0°". In this phase difference calculation process S12, one phase difference θ is calculated as described above for the track voltage V111 and local voltage V121, which were acquired 200 times each over 100 m seconds in the acquisition process S11.

[0071] In the phase difference calculation process S12 shown in Figure 4, once one phase difference θ is calculated, a state change detection process S13 is executed to detect changes in the occupancy status of section A11 based on the 200 track voltages V111 and the one phase difference θ at that calculation point. This state change detection process S13 is performed by the state recognition unit 1D, with part of the processing being delegated to the information generation unit 1F.

[0072] Figure 6 is a time chart showing an example of the time variation of the occupancy status in a section of the track circuit shown in Figures 1 to 3, and the corresponding time variation of track voltage, local voltage, and phase difference.

[0073] The example in Figure 6 takes one of several sections A11 as an example, and shows how the train's presence status changes in the order of unoccupied, occupied, ahead occupied, and unoccupied as time progresses. Specifically, it shows an example where the train is unoccupied, with no trains in the preceding section A11 and the section A11 in question, then enters the section A11 and becomes occupied, then moves to the preceding section A11 and becomes ahead occupied, and then moves to the next section A11 and becomes unoccupied.

[0074] In the state change detection process S13, the above-mentioned changes in the track occupancy status are identified based on the 200 track voltages V111 acquired in the acquisition process S11 and one phase difference θ calculated in the phase difference calculation process S12.

[0075] As shown in Figure 6, the track voltage V111 acquired in acquisition process S11 is an AC voltage. When section A11 is empty, the track voltage V111 is an AC voltage corresponding to the first AC voltage from the first power supply E11 shown in Figure 1. When section A11 is occupied, the section rail L11 is short-circuited and the amplitude of this track voltage V111 becomes 0V, and when the train is ahead, the waveform of the AC voltage is inverted. Then, when section A11 changes from being occupied ahead to being empty, the waveform is inverted again and the track voltage V111 returns to the original AC voltage. In acquisition process S11, 200 of these track voltages V111, whose AC waveform changes in this way as the train moves, are acquired over 100 m seconds at a sampling interval of 0.5 m seconds. In state change detection process S13, first, the information generation unit 1F calculates the track voltage amplitude value V111a, which is the amplitude of the AC waveform drawn by these 200 track voltages V111. The track voltage amplitude value V111a is approximately the same when the track is empty and when the track is ahead (1.2V as an example in Figures 6 and 7), and becomes 0V when the track is occupied. Furthermore, when the track changes from being ahead to empty, it momentarily becomes 0V in accordance with the switching operation of the track relay L13 shown in Figure 1.

[0076] Here, the local voltage V121 acquired in acquisition process S11 is also an AC voltage, but since it is the voltage of the local power distribution line L12 which is installed separately from the section rail L11, the local voltage V121 is not affected by the movement of the train and maintains a constant AC waveform. For this reason, the local voltage V121 is used as a reference in calculating the phase difference θ, as explained with reference to Figure 5.

[0077] In the state change detection process S13, the local voltage amplitude value V121a, which is the amplitude of the AC waveform of the local voltage V121 acquired 200 times over 100 milliseconds at a sampling interval of 0.5 milliseconds, is calculated by the information generation unit 1F. The local voltage amplitude value V121a, for which the waveform does not change, is approximately constant (110V as an example in Figures 6 and 7). The orbital voltage amplitude value V111a and the local voltage amplitude value V121a calculated by the information generation unit 1F are used in the subsequent state information generation process J11.

[0078] After calculating the track voltage amplitude value V111a and the local voltage amplitude value V121a, the state change detection process S13 uses the state recognition unit 1D to determine the presence status. For this determination, the track voltage amplitude value V111a and the phase difference θ calculated in the phase difference calculation process S12 are used. As shown in Figure 6, the phase difference θ of the track voltage V111 with respect to the local voltage V121 is a leading phase of +90° when there is no track, 0° when there is a track, and a lagging phase of -90° when there is a track ahead. In the state change detection process S13, first, it is determined whether there is a track in section A11 based on whether the track voltage amplitude value V111a is 0V and the phase difference θ is 0°. Also, it is determined whether there is no track in section A11 based on whether the track voltage amplitude value V111a is greater than 0V and the phase difference θ is a leading phase with a positive sign. Furthermore, whether or not section A11 is ahead of the track is determined by whether the track voltage amplitude value V111a is greater than 0V and the phase difference θ is a lagging phase with a negative sign.

[0079] If the occupancy status determined in this way differs from the occupancy status determined based on the previous track voltage amplitude value V111a and the phase difference θ, a change in the occupancy status is detected. Furthermore, when a change in the occupancy status is detected, the point in time when the change line of the track voltage amplitude value V111a leading up to the change intersects with a predetermined threshold V111b is calculated as the time of occurrence ST11 of the state change.

[0080] In the flowchart of Figure 4, if no change in the track occupancy status is detected in the state change detection process S13 (NO determination), the process proceeds to the first period determination process S15, which will be described later. On the other hand, if a change in the track occupancy status is detected in the state change detection process S13 (YES determination), the period setting process S14 is executed by the period setting unit 1E. In the period setting process S14, based on the time ST11 when the state change occurred as detected in the state change detection process S13, an unstable period T1 is set during which the track voltage V111 becomes unstable as a result of the state change.

[0081] Figure 7 is a schematic diagram showing how the unstable period is set in the period setting process shown in Figure 4. In this example in Figure 7, the unstable period T1 is set when the track presence changes from unoccupied → occupied → forward occupied → unoccupied, along with the changes in the track voltage amplitude value V111a and the phase difference θ. Figure 7 also shows the local voltage amplitude value V121a, which remains approximately constant throughout the entire process.

[0082] In the example shown in Figure 6 above, a threshold V111b that is approximately constant throughout the entire process is shown as the threshold V111b for the orbital voltage amplitude value V111a used to calculate the time ST11 when the state change occurs. The threshold V111b in Figure 6 is shown schematically for the sake of illustration simplification, and strictly speaking, in this embodiment, two thresholds V111b-1 and V111b-2 are used as shown in Figure 7. That is, when the orbital voltage amplitude value V111a changes from a value to "0", the threshold V111b-1, which is closer to the value, is used. On the other hand, when the orbital voltage amplitude value V111a changes from "0" to a value, the threshold V111b-2, which is closer to "0", is used.

[0083] In the state change detection process S13 described above, a state change is detected in the track voltage amplitude value V111a from a value to "0" or from "0" to a value, and the time ST11 at which the state change occurs is calculated, then the period setting process S14 sets the unstable period T1. In the period setting process S14, a predetermined period T11 starting from the time ST11 at which the state change occurs is set as the unstable period T1, and a predetermined period T12 ending from the time ST11 at which the state change occurs is also added to the unstable period T1. In other words, in the period setting process S14, the period T11 is set as the sum of the two periods T11 and T12 that surround the time ST11 at which the state change occurs. The predetermined length of the unstable period here refers to the period during which the track occupancy state switchover occurs. The predetermined length of this unstable period is influenced by factors such as the response speed of the track relay L13, the contact resistance between the rail and the wheel, and the length of the block section. It is predetermined by considering the time constants (rise time, fall time) of the amplitude change of the track voltage V111.

[0084] In this case, when the track presence changes, the track voltage amplitude value V111a may momentarily change to "0" before changing back to a value. An example of such a change is shown on the right side of Figure 7.

[0085] In this case, first, an unstable period T1 is set, which is the sum of a period T11 starting from the point of change to "0", i.e., the point of occurrence of the apparent state change to being present ST21, and a period T12 ending from the point of occurrence ST21. Here, Figure 7 schematically shows how the set period after the point of occurrence ST21 is extended within the unstable period T1 once it has been set, using a graph G11 that represents the passage of time after the point of occurrence ST21.

[0086] As shown in graph G11, if a new state change from "0" to a value is detected during the initially set instability period T1, the instability period T1 is extended based on the time ST22 at which this new state change occurred. This extension is achieved by resetting a new period T11 starting from the time ST22 at which the new state change occurred. As a result, the period after the first state change occurred ST21 is extended, and a new instability period T2 is set, which is the sum of the period T12 before the first state change occurred ST21 and the extended period T21 after ST21.

[0087] Furthermore, in Figure 7, the time elapsed after the state change ST11 is also shown in graph G11 for the state change from non-occupied → occupied → forward occupied. In graph G11, the period T11 set at the state change time ST11 is completed without undergoing the extension seen in the example of the state change from forward occupied → non-occupied.

[0088] In this case, during a state change, the instantaneous change in the orbital voltage amplitude value V111a to "0" may occur not just once, as shown in Figure 7, but may be repeated multiple times.

[0089] Figure 8 is a schematic diagram illustrating how an instability period is established when the amplitude of the orbital voltage changes instantaneously to "0" multiple times. Figure 8 also shows graph G21, which represents the time elapsed since the first state change occurred at ST31.

[0090] Figure 8 shows an example where the orbital voltage amplitude V111a changes instantaneously to "0" four times, along with the changes in the local voltage amplitude V121a and the phase difference θ. Figure 8 also shows graph G21, which represents the time elapsed since the first state change occurred at ST31.

[0091] In this example, a period T11 is first set, starting from the point ST31 where the first state change occurs, from "Value" to "0". Subsequently, a new period T11 is set, starting from the point ST32 where the state change occurs, from "0" to "Value", before the end of period T11. This process of setting the period again is repeated. As a result, the unstable period T3 is the sum of the period T31 from the point ST31 where the first state change occurred until the end of period T11 after the point ST33 where the last state change occurred, and the period T12 before the point ST31 where the first state change occurred.

[0092] In the flowchart shown in Figure 4, once the period setting process S14 described above is completed, the process returns to the acquisition process S11 and the subsequent processes are repeated.

[0093] On the other hand, if no change in the occupancy status is detected in the state change detection process S13 (NO determination), and the process proceeds to the first period determination process S15 described later, the first period determination process S15 determines whether the current time is within the period of instability. The first period determination process S15 is executed by the storage unit 1G. If it is within the period of instability (YES determination), the process proceeds to the signal anomaly detection process S20 described later. On the other hand, if it is not within the period of instability (NO determination), the storage unit 1G executes a second period determination process S16 to determine whether it is immediately after the end of an already set period of instability.

[0094] If it is immediately after the end of the unstable period (YES determination), the storage unit 1G executes the normal acquisition information storage process S17. In the normal acquisition information storage process S17, the storage unit 1G stores the acquisition result storage area 1G-2, which includes at least 200 orbital voltages V111 acquired in acquisition processes S11 at 100ms acquisition intervals. This storage to the acquisition result storage area 1G-2 will be explained in detail later with reference to Figure 10. After the normal acquisition information storage process S17, the process proceeds to the information generation process S18 by the information generation unit 1F.

[0095] On the other hand, if it is not immediately after the end of the unstable period (NO determination), the normal information acquisition and storage process S17 is not performed, and the process proceeds to the information generation process S18.

[0096] In the information generation process S18, state information J11 representing the state of the orbital circuit L1 is generated based on the various calculation results up to this point.

[0097] Figure 9 shows how the state information of the track circuit is generated by the process represented by the flowchart in Figure 4, according to the time chart shown in Figure 6.

[0098] As described above, in the process shown in the flowchart of Figure 4, an unstable period is set each time the occupancy status changes, and if it is not within that unstable period, the state information J11 of the track circuit L1 is generated. As shown in Figure 9, the state information J11 includes the occupancy status J111, the track voltage amplitude value V111a, the local voltage amplitude value V121a, the phase difference θ, and the judgment result regarding the abnormality of the track circuit L1. The occupancy status J111 is the status grasped in the state change detection process S13. The track voltage amplitude value V111a and the local voltage amplitude value V121a are amplitude values ​​calculated in this state change detection process S13 for state grasp. The phase difference θ is the phase difference calculated in the phase difference calculation process S12 and used for state grasp in the state change detection process S13. Furthermore, in the information generation process S18, the track voltage amplitude value V111a, the local voltage amplitude value V121a, and the phase difference θ calculated up to this point are compared with a threshold value corresponding to the track occupancy state J111 at the time of calculation to determine if there is an abnormality in the track circuit L1. To reiterate, this abnormality determination is separate from the detection of signal abnormalities performed in the period setting unit 1E as the unstable period is extended. The detection of signal abnormalities by the period setting unit 1E is performed in the signal abnormality detection process S20 described later. In the information generation process S18, the track occupancy state J111, the track voltage amplitude value V111a, the local voltage amplitude value V121a, the phase difference θ, and the determination results regarding the abnormality of the track circuit L1 are combined into a single information set to generate state information J11.

[0099] In the flowchart shown in Figure 4, following the information generation process S18 described above, the following information storage process S19 is executed by the storage unit 1G. In this information storage process S19, the state information J11 generated in the information generation process S18 is stored in the information storage area 1G-1. After the information storage process S19, the process returns to the acquisition process S11, and the subsequent processes are repeated.

[0100] Here, if the first period determination process S15 described above determines that the period is unstable (YES determination), the period setting unit 1E executes the signal anomaly detection process S20, which is as follows. The following explanation of this signal anomaly detection process S20 will mainly refer to the contents illustrated in Figure 8.

[0101] In the signal anomaly detection process S20, the occurrence of a signal anomaly related to the occupancy state J111 is detected based on a comparison between the elapsed time since the first state change was detected during the unstable period T3, i.e., the period T31 after the occurrence of the state change ST31, and a predetermined timeout threshold. The bottom of graph G21 in Figure 8 shows how the period T31 after the occurrence of the first state change ST31 is compared with the predetermined timeout threshold. In this example in Figure 8, the period T31 after the occurrence of the first state change ST31 reaches the timeout threshold before the end of the period T31. This means that a signal anomaly has occurred in which the occupancy state J111 does not stabilize and state changes are repeated in a short period of time, and the signal anomaly detection process S20 shown in Figure 4 detects the occurrence of a signal anomaly related to the occupancy state J111 in such a case. If this timeout threshold is too long, the desired signal anomaly cannot be detected, and conversely, if it is too short, even state changes that would normally occur may be judged as an anomaly. Therefore, the acceptable range will be predetermined based on factors such as the frequency of occurrence and the installation location.

[0102] If the signal anomaly is detected in the signal anomaly detection process S20 (YES determination), the following signal anomaly acquisition information storage process S21 is executed by the storage unit 1G. In this signal anomaly acquisition information storage process S21, the storage unit 1G stores in the signal anomaly storage area 1G-3 at a rate that includes at least 200 orbital voltages V111 acquired in the acquisition process S11 over an acquisition interval of 100 milliseconds as source data for detecting the occurrence of the signal anomaly. The storage in this signal anomaly storage area 1G-3 will also be explained in detail later with reference to Figure 10, along with the storage in the acquisition result storage area 1G-2. After the signal anomaly acquisition information storage process S21, the process returns to the acquisition process S11, and the subsequent processes are repeated.

[0103] On the other hand, if no signal anomaly is detected in the signal anomaly detection process S20 (NO determination), the various storage processes described above are not performed, the process returns to the acquisition process S11, and the subsequent processes are repeated.

[0104] In the process shown in the flowchart of Figure 4, various types of information are stored in the memory unit 1G as follows.

[0105] Figure 10 is a schematic diagram showing how various types of information are stored in the memory unit during the process represented by the flowchart in Figure 4.

[0106] The memory unit 1G is provided with three memory areas: information memory area 1G-1, acquisition result memory area 1G-2, and signal anomaly memory area 1G-3. First, the state information J11 of the track circuit L1 is stored in the information memory area 1G-1. The contents of the information memory area 1G-1 are updated at an update interval of 100 milliseconds by repeatedly executing the process shown in the flowchart of Figure 4, except during periods of instability associated with changes in the track occupancy status J111.

[0107] The acquisition result storage area 1G-2 stores data that includes at least 200 track voltages V111 acquired at a sampling interval of 0.5 ms during an acquisition period of 100 ms, starting immediately after the end of the unstable period. In this embodiment, the acquisition result storage area 1G-2 is divided into three types of track presence states J111: present, forward present, and non-present. The data is stored in the area corresponding to the track presence state J111 when the data was obtained. In this embodiment, regardless of the track presence state J111, 200 local voltages V121 acquired at a sampling interval of 0.5 ms during the same 100 ms acquisition period as the track voltages V111 are also stored as data. On the other hand, the phase difference θ calculated at a calculation interval of 100 ms is not stored when the track presence state J111 is such that the phase difference θ cannot be calculated and is set to "0°". The phase difference θ is stored along with the track voltage V111 and local voltage V121 when the occupancy status J111 is forward occupancy and unoccupancy. The contents of the acquired result storage area 1G-2 are updated each time the occupancy status J111 changes, specifically for the area corresponding to the changed occupancy status J111.

[0108] The signal anomaly storage area 1G-3 stores 200 orbital voltages V111 and local voltages V121 acquired during the signal anomaly acquisition period corresponding to the signal anomaly detection timing described above, as well as the phase difference θ calculated based on them. The signal anomaly acquisition period referred to here is the 100 msec acquisition period of the orbital voltages V111 and pole voltages V121 acquired in acquisition process S11 as the source data for signal anomaly detection in the process shown in the flowchart of Figure 4. The contents of the signal anomaly storage area 1G-3 are updated each time a signal anomaly is detected.

[0109] In this embodiment, the contents stored in the memory unit 1G are output by the output unit 1H shown in Figure 3.

[0110] Figure 11 is a schematic flowchart illustrating the process flow in which the output unit shown in Figure 3 outputs the contents stored in the memory unit.

[0111] The processing in this flowchart begins when power is supplied to the track circuit monitoring device 1 and it starts up. First, initialization S31 is performed for each element, and then the device enters a first determination waiting state S32 to determine whether a predetermined output timing has arrived. Examples of output timings include the passage of a certain time interval or the completion of 100ms of storage processing by the storage unit 1G after a change in the track occupancy status. If the output timing has arrived (YES), the process proceeds to the information output processing S34 described below. On the other hand, if the output timing has not yet arrived (NO), the device enters a second determination waiting state S33 to determine whether a read request has been sent from the external device 2 or PC 3 shown in Figure 1. If there is no read request (NO determination), the process returns to the first determination waiting state S32, and the subsequent processing is repeated. When a read request is sent (YES determination), the information output processing S34 regarding the contents stored in the storage unit 1G is executed at that point. Furthermore, if the output timing arrives in the first judgment waiting state S32 (YES), this information output process S34 is also executed. In the information output process S34, unless otherwise specified, all stored contents of the information storage area 1G-1, the acquired result storage area 1G-2, and the signal abnormality storage area 1G-3 are output. On the other hand, if a read target is specified in the read request, the stored contents of the area corresponding to that read target are output. In addition, for the acquired result storage area 1G-2, it is also possible to specify the occupancy status J111 in the read request, and if the occupancy status J111 is specified, the stored contents for the occupancy status J111 corresponding to that specification are output.

[0112] The track circuit monitoring device 1 described above can achieve the following effects. Specifically, in this embodiment, the storage target, which includes at least the track voltage V111 acquired during a predetermined acquisition period, is stored in the acquisition result storage area 1G-2 of the storage unit 1G. The track voltage V111 acquired at sampling intervals during the acquisition period represents the waveform of the time change of this track voltage V111, i.e., the voltage waveform. Therefore, if there is distortion in the voltage waveform of the track voltage V111 in the track circuit L1, the degree of distortion of the voltage waveform can be determined from the track voltage V111 stored as a storage target in the acquisition result storage area 1G-2. Furthermore, if there is no distortion in the voltage waveforms of the track voltage V111 and local voltage V121, as shown in Figure 5, the phase difference θ can be calculated from the time difference Δt from the intersection time between the center voltage of the amplitude and the waveforms of the track voltage V111 and local voltage V121 that are the acquisition targets. In this embodiment, in addition to the orbital voltage V111, the local voltage V121 and the phase difference θ are also stored. Therefore, if there is a significant error between the original phase difference and the calculated phase difference θ, the cause of the error can be verified by determining the degree of distortion in the voltage waveforms of the orbital voltage V111 and the local voltage V121.

[0113] In this embodiment, the memory unit 1G stores the data to be stored as the acquisition period, which is the period from the start timing after the occurrence of a change in the occupancy state J111. With this configuration, the track voltage V111 from the start timing after the occurrence of a change in the occupancy state, when there is a high possibility of distortion in the voltage waveform of the track voltage V111, is stored, so the degree of distortion in the voltage waveform of the track voltage V111 can be determined more effectively.

[0114] Furthermore, in this embodiment, the acquisition result storage area 1G-2 in the storage unit 1G is divided into three types of occupancy states J111: occupant, forward occupant, and non-occupant. The storage target in the acquisition result storage area 1G-2 is stored in the area corresponding to the occupancy state J111 at the time the storage target was obtained. With this configuration, the voltage waveform of the track voltage V111 can be analyzed for each of the three types of occupancy states J111, making it possible to determine in detail the degree of distortion of the voltage waveform of the track voltage V111 for each occupancy state J111.

[0115] Furthermore, in this embodiment, the memory unit 1G does not store the phase difference θ if the occupancy state J111 at the time the phase difference θ is calculated is occupancy, but stores it in the area corresponding to each occupancy state J111 if the occupancy state is forward or not occupancy. With this configuration, when the phase difference θ is to be stored, the phase difference θ is not stored when the value is zero (occupancy), and the phase difference θ for forward occupancy and not occupancy, which have values ​​and are useful for analysis, is stored. This makes it possible to efficiently store the phase difference θ while suppressing the amount of storage area used in the memory unit 1G.

[0116] Furthermore, in this embodiment, the information generation unit 1F generates state information J11 based on the track voltage V111 and local voltage V121 during the period excluding the unstable period associated with changes in the track occupancy state J111, and the phase difference θ calculated using these voltages. The storage unit 1G stores the data to be stored as an acquisition period, starting from a start timing corresponding to the end of the unstable period. With this configuration, highly accurate state information J11 can be obtained based on the stable track voltage V111, local voltage V121, and phase difference θ during the period excluding the unstable period. In addition, by setting the start timing of storage to a timing corresponding to the end of the unstable period, it is possible to store data in a stable state, and thus the degree of distortion of the voltage waveform in the track voltage V111 can be determined with high accuracy.

[0117] Furthermore, in this embodiment, the period setting unit 1E extends the unstable period and detects the occurrence of a signal anomaly in the track circuit L1 based on a comparison of the elapsed time during the extended unstable period with the timeout threshold. The storage unit 1G stores the data to be stored during the signal anomaly acquisition period, which corresponds to the timing of the signal anomaly detection, in the signal anomaly storage area 1G-3. With this configuration, the occurrence of a signal anomaly in which a short-term state change is repeated beyond the timeout threshold can be effectively detected, and the data to be stored when such a signal anomaly occurs can be stored separately. As a result, even when a signal anomaly occurs, the degree of distortion of the voltage waveform of the track voltage V111 can be effectively determined.

[0118] Furthermore, in this embodiment, the first AC voltage and the second AC voltage are AC voltages having one period selected from a predetermined set of periods, and the storage unit 1G stores the data to be stored using the least common multiple of the multiple periods as the acquisition period. The sampling interval in the orbital voltage acquisition unit 1A and the local voltage acquisition unit 1B is a time interval of 1 / 10 or less of the above-mentioned one period. Specifically, the acquisition period is set to 100 milliseconds, which is an integer multiple (in this case, 1) of 100 milliseconds, the least common multiple of the 1 / 50 second period and the 1 / 60 second period. The sampling interval is set to 0.5 milliseconds, which is 1 / 10 or less of the 1 / 50 second period and 1 / 10 or less of the 1 / 60 second period. With this configuration, regardless of whether the first AC voltage and the second AC voltage have a 1 / 50 second period or a 1 / 60 second period, an orbital voltage V111 of sufficient length for distortion determination can be stored. Furthermore, by setting the sampling interval in the orbital voltage acquisition unit 1A and the local voltage acquisition unit 1B to 1 / 10 or less of the above period, the orbital voltage V111 can be stored with sufficient resolution for checking the voltage waveform while keeping the amount of data stored in the memory unit 1G to a minimum.

[0119] Furthermore, in this embodiment, an output unit 1H is provided that reads and outputs the contents of the storage unit 1G when a predetermined output timing arrives, or in response to a request from outside the device. With this configuration, compared to, for example, a configuration in which the storage unit 1G stores data in a portable memory and an operator removes the portable memory during maintenance, the workload can be reduced to obtain the stored contents.

[0120] It should be noted that the embodiments described above merely represent typical forms of track circuit monitoring devices, and the track circuit monitoring device is not limited to these. In other words, the track circuit monitoring device can be implemented in various modified forms without departing from its core principles.

[0121] For example, in the above embodiment, as an example of a track circuit, a track circuit L1 is provided in which a section rail L11 and a local power distribution line L12 are connected via a track relay L13, and the track relay L13 detects the presence of a train. However, the track circuit is not limited to this, and any circuit that detects the presence of a train based on the voltage of the section rail and the voltage of the local power distribution line is acceptable, regardless of its specific circuit configuration.

[0122] Furthermore, in the above-described embodiment, as an example of a track circuit monitoring device, a track circuit monitoring device 1 is provided in which a track voltage V111 and a local voltage V121, to which a DC offset is applied so as to always be a positive value, are input to a positive single-supply MPU 13. In this track circuit monitoring device 1, the midpoint voltage V112 of the track voltage V111 and the midpoint voltage V122 of the local voltage V121, which are used for phase difference calculation, are both voltages corresponding to the DC offset. However, the track circuit monitoring device is not limited to this, and may also be equipped with an MPU with a positive / negative dual-supply specification. In this case, the MPU receives track voltages and local voltages that fluctuate in both positive and negative directions around 0V without applying a DC offset, and each midpoint voltage becomes 0V.

[0123] Furthermore, in the above-described embodiment, a storage unit 1G is provided as an example of a storage unit that stores local voltage V121 and phase difference θ in the acquisition result storage area 1G-2 in addition to orbital voltage V111. However, the storage unit is not limited to this, and may store only orbital voltage, or only orbital voltage and local voltage.

[0124] Furthermore, in the above-described embodiment, a memory unit 1G is provided as an example of a memory unit that stores data to be stored as an acquisition period, starting from the start timing after the occurrence of a change in the occupancy state J111. However, the start timing of storage is not limited to this, and any timing can be set. However, as mentioned above, by adopting a start timing after the occurrence of a change in the occupancy state J111, the degree of distortion of the voltage waveform of the track voltage V111 can be determined more effectively.

[0125] Furthermore, in the above-described embodiment, an example of an acquisition result storage area is shown as an acquisition result storage area G1-2, which is divided into three types of occupancy states J111, and the storage target is stored in the area corresponding to the occupancy state J111 at the time of acquisition. However, the acquisition result storage area is not limited to this, and the storage target may be stored without distinction of occupancy states. However, as mentioned above, by storing the storage target in the area corresponding to the occupancy state J111 at the time of acquisition, the degree of distortion of the track voltage V111 can be determined in detail for each occupancy state J111.

[0126] Furthermore, in the above-described embodiment, as an example of a memory unit, a memory unit 1G is provided which does not store the phase difference θ in the acquisition result memory area G1-2 when the occupancy status J111 is occupancy, but stores the phase difference θ in the acquisition result memory area G1-2 when the forward occupancy status and the non-occupancy status are present. However, the memory unit is not limited to this, and may not store the phase difference in the acquisition result memory area regardless of the occupancy status, or even if it does store it, it may store it uniformly without distinguishing between occupancy status and non-occupancy status. However, as mentioned above, by not storing the phase difference θ in the acquisition result memory area G1-2 when the occupancy status is occupancy, but storing it in the acquisition result memory area G1-2 when the forward occupancy status and the non-occupancy status are present, the phase difference θ can be efficiently stored while reducing the amount of memory area used.

[0127] Furthermore, in the above-described embodiment, as an example of a track circuit monitoring device, a track circuit monitoring device 1 is provided in which an information generation unit 1F generates state information J11 based on the track voltage V111 etc. during the period excluding the unstable period, and a storage unit 1G stores the items to be stored according to the end time of that period. However, the track circuit monitoring device is not limited to this, and may generate state information J11 and store items to be stored regardless of the unstable period. However, as mentioned above, generating state information J11 and storing items to be stored based on the unstable period improves the accuracy of the state information J11 and allows for a highly accurate determination of the degree of distortion in the track voltage V111.

[0128] Furthermore, in the above-described embodiment, as an example of a track circuit monitoring device, a track circuit monitoring device 1 is provided in which the storage unit 1G stores in the signal abnormality storage area 1G-3 the storage targets for a period corresponding to the timing of detection of signal abnormalities due to the extension of the unstable period. However, the track circuit monitoring device is not limited to this, and the storage unit 1G may store storage targets regardless of the detection of the occurrence of the above-described signal abnormality. However, as mentioned above, by storing storage targets for a period corresponding to the timing of detection of signal abnormalities, it is possible to effectively determine the degree of distortion of the track voltage V111 when a signal abnormality occurs.

[0129] Furthermore, in the above-described embodiment, as an example of a track circuit monitoring device, a track circuit monitoring device 1 is provided in which a memory unit 1G stores the track voltage V111 and local voltage V121 with an acquisition period of 100 m seconds. The acquisition period of 100 m seconds is an integer multiple (here, 1) of 100 m seconds, which is the least common multiple of the two types of periods, 1 / 50 second period and 1 / 60 second period, that are the source of selection for the periods of the first AC voltage and the second AC voltage. In addition, in this track circuit monitoring device 1, the sampling interval in the track voltage acquisition unit 1A and the local voltage acquisition unit 1B is 0.5 m seconds, which is a time interval of 1 / 10 or less of the above-mentioned period. However, the track circuit monitoring device is not limited to this. The acquisition period when the memory unit stores the track voltage and local voltage may be set to a period unrelated to the periods of the first AC voltage and the second AC voltage, and the sampling interval in the track voltage acquisition unit and the local voltage acquisition unit may also be set to an interval unrelated to the above-mentioned period. However, as mentioned above, by setting the acquisition period for storage in the memory unit to an integer multiple of the least common multiple of the multiple periods from which the periods of the first and second AC voltages are selected, it is possible to store orbital voltages V111 of a length sufficient for strain detection. Furthermore, as mentioned above, by setting the sampling interval to a time interval of 1 / 10 or less of one of the periods, it is possible to store orbital voltages V111 with sufficient resolution for strain detection while keeping the amount of data stored in the memory unit 1G low. Note that the specific acquisition period when using an integer multiple of the least common multiple of multiple periods, and the specific sampling interval when using a time interval of 1 / 10 or less of one of the periods, can be set to any length as long as the respective conditions are met.

[0130] Furthermore, in the above-described embodiment, as an example of a track circuit monitoring device, a track circuit monitoring device 1 is provided which includes an output unit 1H that reads and outputs the contents of the memory unit 1G when a predetermined output timing arrives or in response to a request from outside the device. However, the track circuit monitoring device is not limited to this, and the output unit described above may not be provided. In this case, for example, the memory unit 1G may be stored in a portable memory, and a worker may take out the portable memory during maintenance, etc. However, as mentioned above, providing the output unit 1H reduces the workload and allows for obtaining the stored contents. In the above-described embodiment, the output unit 1H determines both the arrival of the output timing and whether or not there is a request from outside the device and performs information output processing S34. However, the output unit is not limited to this, and as long as it reads and outputs the contents of the memory unit when a predetermined output timing arrives or in response to a request from outside the device, it may determine only one of these and perform information output processing. [Explanation of symbols]

[0131] 1 Track circuit monitoring device 1A Track voltage acquisition unit 1B Local voltage acquisition unit 1C Phase difference calculation section 1D Status Assessment Unit 1E Period setting section 1F Information generation department 1G storage 1G-1 Information storage area 1G-2 Acquisition result storage area 1G-3 Signal abnormality storage area 1H Output Section 2 External equipment 3 PC 4 Power supply 11. Track Voltage Processing Unit 12 Local voltage processing unit 13 MPU 14,21 RS485 transmission section 15 Power supply section 16 Oscillator 17 Reset IC 22 Microcontroller Circuits 111 Step-down circuit for track 112 Isolation amplifier for track use 113 First orbital LPF 114 HPF for the first orbit 115 Second orbital LPF 116 HPF for the second orbit 117 Inverting amplifier for orbit 121 Local step-down circuit 122 Local isolation amplifier 123 Local LPF 124 Local HPF 125 Local Inverting Amplifier 131, 132, 133 AD converters 134,135 UART A1 Block Section A11 section A2 In-venue section E11 First Power Supply E12 Second power supply G11, G21 graph Lines drawn by the time evolution of GL1 and GL2 J11 Status Information J111 On-line status L1 track circuit L1a Railway Rail L11 Section Rail L12 Local distribution line L13 Track Relay L131 orbital coil L132 Local Coil S11 Acquisition process S12 Phase difference calculation process S13 State change detection process S14 Period setting process S15 First period determination process S16 Second period determination process S17 Normal information acquisition and storage processing S18 Information generation process S19 Information storage processing S20 Signal Anomaly Detection Process S21 Signal Anomaly Acquisition Information Storage Processing S31 Initialize S32 First judgment waiting state S33 Second judgment waiting state S34 Information Output Processing ST1 Station ST11, ST21, ST22, ST31, ST32, ST33 Occurrence Time SG1 traffic light T period T1, T2, T3 Unstable Periods Periods T11, T12, T21, T31 TC1 Track Crossing Time TC2 local crossing time V11 section rail voltage V12 Local distribution line voltage V111 orbital voltage V111a Orbital voltage amplitude value V111b, V111b-1, V111b-2 thresholds V112, V122 Midpoint Voltage V113, V123 Pair of Voltages V121 Local Voltage V121a Local voltage amplitude value θ phase difference Δt time difference

Claims

1. In a track circuit monitoring device that monitors the state of a track circuit for detecting the presence of a train in a section of a railway track that is electrically divided into multiple sections, based on the voltage of the section rail to which a first AC voltage is applied and which is electrically short-circuited when a train is present, and the voltage of a local power distribution line installed near the section rail to which a second AC voltage is applied, A track voltage acquisition unit acquires the track voltage used for detecting the occupancy status based on the voltage of the aforementioned section of rail at a predetermined sampling interval, A local voltage acquisition unit acquires the local voltage used for detecting the presence of the line based on the voltage of the local distribution line at the sampling interval, A phase difference calculation unit that calculates the phase difference between the orbital voltage and the local voltage, A status recognition unit that recognizes the occupancy status in the section based on the track voltage and the phase difference, An information generation unit that generates state information representing the state of the track circuit based on the track voltage, the local voltage, the phase difference, and the track presence status, A storage unit that stores the state information and stores at least the track voltage among the track voltage acquired by the track voltage acquisition unit, the local voltage acquired by the local voltage acquisition unit, and the phase difference calculated by the phase difference calculation unit during a predetermined acquisition period, in an acquisition result storage area different from the information storage area in which the state information is stored. A track circuit monitoring device characterized by being equipped with the following features.

2. The track circuit monitoring device according to claim 1, characterized in that the storage unit stores the storage target as the acquisition period, which is the period from the start timing after the occurrence of the change in the track occupancy status grasped by the status grasping unit.

3. The presence status of each section has three states: presence (the train is present in the section), forward presence (the train has moved to a section ahead in the direction of travel of the train as viewed from the section), and non-presence (the train has moved from the forward section as well). The track circuit monitoring device according to claim 1, characterized in that the acquisition result storage area in the storage unit is divided into areas for the occupying track, the forward occupying track, and the non-occupying track, and the storage target is stored in an area corresponding to the occupying state when the storage target was obtained.

4. The storage unit also stores the phase difference, and with respect to the phase difference, it does not store the occupancy status when the occupancy status is the occupancy status when the phase difference is calculated, but stores it in the area corresponding to the occupancy status when the occupancy status is the forward occupancy status and the non-occupancy status, as described in claim 3.

5. The system further includes a period setting unit that sets an unstable period during which the track voltage becomes unstable due to the change in state, based on the timing of the occurrence of the state change in the track occupancy state as determined by the state recognition unit. The information generation unit generates the status information based on the track voltage and local voltage acquired during the period excluding the unstable period set by the period setting unit, the phase difference calculated using the track voltage and local voltage, and the track occupancy status grasped using the track voltage and phase difference. The track circuit monitoring device according to claim 1, characterized in that the storage unit stores the storage target as the acquisition period, which is the period from the start timing corresponding to the end of the unstable period.

6. If a new state change in the track occupancy status occurs during the unstable period set by the period setting unit, the unstable period is extended based on the time at which the new state change occurred, and a signal abnormality in the track circuit is detected based on a comparison of the elapsed time since the first state change occurred in the extended unstable period with a predetermined timeout threshold. The track circuit monitoring device according to claim 5, characterized in that when the period setting unit detects the signal abnormality, the storage unit stores the data to be stored during the signal abnormality acquisition period corresponding to the detection timing in a signal abnormality storage area that is different from the acquisition result storage area.

7. The first AC voltage and the second AC voltage are AC voltages having one period selected from a predetermined set of periods. The storage unit stores the storage target with the acquisition period set to an integer multiple of the least common multiple of the multiple periods. The track circuit monitoring device according to claim 1, characterized in that the sampling interval in the track voltage acquisition unit and the local voltage acquisition unit is a time interval of 1 / 10 or less of the one period.

8. The track circuit monitoring device according to claim 1, further comprising an output unit that reads and outputs the contents of the storage unit when a predetermined output timing arrives, or in response to a request from outside the device.

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