On-board communication device and self-diagnosis method for on-board communication device

Abstract

To enable normal self-diagnosis of a power wave monitor to be performed even when a ground element and a gangboard exist in the vicinity of an on-vehicle element in an on-vehicle communication device.SOLUTION: An on-vehicle communication device mounted on a vehicle that travels on a locus comprises: an on-vehicle element which transmits a power wave to a ground element installed on the locus and receives an information wave from the ground element; an information wave reception unit which transmits data obtained by modulating the information wave received by the on-vehicle element to a control unit; a power wave transmission circuit which transmits the power wave to the on-vehicle element according to a power wave transmission instruction output from the control unit; a power wave monitor which outputs a power wave monitor signal based on the power wave level of the power wave transmission circuit; and a control unit which performs soundness diagnosis of the power wave monitor on the basis of the power wave monitor signal. The on-vehicle communication device includes: a simulated load which has an impedance equivalent to the on-vehicle element; and a load switching circuit which switches the connection destination of the power wave transmission circuit between the on-vehicle element and the simulated load.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to an on-board communication device and a self-diagnosis method for an on-board communication device. [Background technology]

[0002] The on-board transponder equipment mounted on the vehicle transmits and receives telegram information to and from the ground communication equipment installed on the track. Data such as the vehicle's speed limit and location information obtained from the ground communication equipment is used for important vehicle operation control, such as vehicle speed control. There are two types of ground communication equipment: powered ground communication equipment that receives power from the ground equipment, and non-powered ground communication equipment that receives power from the power waves from the on-board transponder equipment and is activated. Both types of ground communication equipment transmit telegram information at a frequency different from the power waves to the on-board communication equipment. Here, since communication between the on-board communication equipment and the ground communication equipment may affect the safety of vehicle operation as mentioned above, the on-board communication equipment is required to communicate reliably with the ground communication equipment.

[0003] In particular, in order to start up the non-powered ground communication device and reliably communicate with it, it is essential to transmit stable power from the on-board transponder device to the ground communication device, so it is important to perform self-diagnosis of the power wave transmission circuit and reliably detect any faults. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-222907 A Summary of the Invention [Problem to be solved by the invention]

[0005] Self-diagnosis of the power wave is performed by a monitor function that monitors the power wave transmission level. The monitor function measures the power wave transmission output and constantly checks whether it is outputting a level that can activate the ground coil. In addition, self-diagnosis of this monitor function itself is also necessary, and the power wave output level is deliberately lowered to check whether the monitor function detects the drop in power wave level and detects a fault. Since this self-diagnosis of the monitor function changes the power wave transmission level, it cannot be performed while the train is moving, but is performed when the on-board transponder device is activated.

[0006] If there is a metal bridge plate installed in a ground coil or a depot pit near the on-board transponder equipment, the impedance will increase due to the resonance frequency of the on-board equipment being shifted by coupling with the ground coil or the effect of eddy currents generated in the bridge plate. This makes it difficult for the power wave current to flow, lowering the monitor value and causing the on-board equipment to be judged as faulty even though there is no abnormality.

[0007] Therefore, Patent Document 1 discloses a method in which, when an on-board device is activated near a ground coil, a power wave at the same level as when the train is moving is output to activate the ground coil and transmit an information wave, and when the information wave from the ground coil is detected, the threshold value of the power wave monitor value is lowered below normal to perform diagnosis.

[0008] However, according to the above method described in Patent Document 1, it is necessary to set in advance a threshold value for the decrease in the power wave monitor value when a ground coil is detected, and if the installation height of the on-board coil is different, the influence of the ground coil changes, so it is necessary to set a threshold value according to the installation height. Furthermore, since a gangway does not transmit information waves, it is not possible to detect that it is near a gangway, and there is a problem that the threshold value for the power wave monitor value cannot be changed.

[0009] The present invention has been made in consideration of the above, and one of its objects is to enable normal self-diagnosis of a power wave monitor in an on-board communication device, even if a ground coil or gangway is present near the on-board coil. [Means for solving the problem]

[0010] In order to solve the above problems, one aspect of the present invention is an on-board communication device mounted on a vehicle running on a track, comprising: an on-board coil that transmits power waves to a ground coil installed on the track and receives information waves from the ground coil; an information wave receiving unit that transmits data obtained by demodulating the information wave received by the on-board coil to a control unit; a power wave transmitting circuit that transmits power waves to the on-board coil in accordance with a power wave transmission instruction output from the control unit; a power wave monitor that outputs a power wave monitor signal based on the power wave level of the power wave transmitting circuit; and a control unit that performs health diagnosis of the power wave monitor based on the power wave monitor signal, and is characterized in that the device is provided with a simulated load having an impedance equivalent to the on-board coil, and a load switching circuit that switches the connection destination of the power wave transmitting circuit between the on-board coil and the simulated load. Effect of the Invention

[0011] According to the present invention, for example, in an on-board communication device, even if a ground coil or a gangway is present near the on-board coil, normal self-diagnosis of the power wave monitor is possible. [Brief description of the drawings]

[0012] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of an on-board communication device according to a first embodiment. [Diagram 2] FIG. 2 is a diagram showing in detail an example of the configuration of an on-board communication device according to the first embodiment. [Diagram 3] FIG. 2 is a diagram showing a configuration example of a load switching circuit of the on-board communication device according to the first embodiment. [Figure 4] FIG. 13 is a diagram for explaining an image of power wave output characteristics. [Diagram 5] A diagram to explain the traveling distance when the disablement of the output of the power wave fault detection signal when the on-board device is activated directly above the gangway is released. [Figure 6] FIG. 11 is a diagram showing an example of the configuration of an on-board communication device according to a second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. The present disclosure is not limited to this embodiment. In the description of the drawings, the same parts are denoted by the same reference numerals. In addition, sub-numbers are added to the same reference numerals to distinguish between a plurality of identical components. In addition, in the description of the embodiments described later, differences from the previously described embodiments will be mainly described, and duplicated description will be omitted.

[0014] [Embodiment 1] FIG. 1 is a diagram illustrating a schematic configuration example of an on-board communication device 1 according to a first embodiment. The on-board communication device 1 is mounted on a vehicle traveling on a track such as a railway. The on-board communication device 1 generates a power wave in an electric power wave transmission circuit 10 in response to an electric power wave transmission command received from a control unit 2, and transmits the power wave to a ground coil 3 installed on the track via a load switching circuit 12 and an on-board coil 13. At this time, an output control unit 11 monitors the output of the electric power wave transmission circuit 10, and when the output level falls outside a specified range, determines that the electric power wave transmission circuit 10 or the on-board coil 13, which is a load, has failed, and transmits a failure detection signal to the control unit 2.

[0015] The on-board communication device 1 also has an on-board terminal 13 and a dummy load 14 having an impedance equivalent to that of the on-board terminal 13 as output destinations of the power wave transmission circuit 10. The power wave transmission circuit 10 includes a load switching circuit 12 that is connected to either the on-board terminal 13 or the dummy load 14. The load switching circuit 12 connects the on-board terminal 13 or the dummy load 14 to the power wave transmission circuit in accordance with a load switching signal 118.

[0016] 2 is a diagram showing in detail an example of the configuration of the on-board communication device 1 according to the embodiment 1. The power wave transmission circuit 10 has an oscillator 101, a preamplifier 102 that amplifies the output of the oscillator 101, a variable attenuator 103 that attenuates the output of the preamplifier 102 to adjust the level, an output stage amplifier 104 that amplifies the power wave level-adjusted by the variable attenuator 103, and a low pass filter (LPF) 105 that removes distortion of the output waveform of the output stage amplifier 104.

[0017] The output control unit 11 includes a power wave control unit 111 that controls the frequency setting and output ON / OFF of the power wave in response to a power wave transmission command received from the control unit 2, a power wave monitor 113a that measures the output current of the power wave transmission circuit 10 and outputs a power wave monitor signal 117a of the power wave transmission circuit 10 according to the power wave level based on the output current, an A / D converter 112a that converts the output of the power wave monitor 113a into a digital signal, and a D / A converter 114 that converts a power wave output level control signal 116 output from the power wave control unit 111 into an analog signal to control the variable attenuator 103. The output control unit 11 transmits a failure detection signal 115 to the control unit 2 when the power wave monitor signal 117a falls outside a specified range.

[0018] The information wave receiving unit 15 has a bandpass filter 151 that removes unnecessary frequencies from the information wave received from the on-board coil 13, a preamplifier 152 that amplifies the output of the bandpass filter 151, an A / D converter 112 that converts the output of the preamplifier 152 into a digital signal, and an information wave control unit 153 that demodulates the converted digital signal and transmits the telegram received from the ground coil to the control unit 2.

[0019] In addition, the on-board communication device 1 is equipped with a transformer 16 for isolation and balanced-to-unbalanced conversion between the on-board terminal 13 and the power wave transmitting circuit 10, and a load switching circuit 12 for connecting either the on-board terminal 13 or the dummy load 14 to the power wave transmitting circuit 10.

[0020] Here, the electric power wave control unit 111 controls the load switching circuit 12 so that the load of the electric power wave transmission circuit 10 becomes the dummy load 14 immediately after the on-board communication device 1 is started. Furthermore, the electric power wave control unit 111 changes the electric power wave output level control signal 116 for self-diagnosis of the electric power wave monitor 113a, and confirms that when the electric power wave output level control signal 116 causes the output level of the electric power wave transmission circuit 10 to be outside the specified range, the electric power wave monitor signal 117a also becomes outside the specified range. After the self-diagnosis of the electric power wave monitor 113a is completed, the electric power wave control unit 111 switches the load switching circuit 12 so that the load of the electric power wave transmission circuit 10 becomes the on-board coil 13, and transitions to normal operation.

[0021] 3 is a diagram showing a configuration example of the load switching circuit 12 of the on-board communication device 1 according to the embodiment 1. The load switching circuit 12 connects either the on-board terminal 13 or the dummy load 14 as a load of the power wave transmission circuit 10 in accordance with a load switching signal 118. The load switching circuit 12 connects the load to the on-board terminal 13 during normal operation, and to the dummy load 14 during self-diagnosis of the power wave monitor 113a.

[0022] Fig. 4 is a diagram for explaining an image of the electric power wave output characteristic, with the horizontal axis representing the intensity of the electric power wave output level control signal 116 and the vertical axis representing the intensity of the electric power wave monitor signal 117. When the electric power wave transmission circuit 10, the output control section 11, and the load of the electric power wave transmission circuit 10 are normal, that is, when there is no ground coil 3 or crossing plate 4 near the on-board coil 13, or when a dummy load 14 is connected, the electric power wave output characteristic 51 shown in Fig. 4 is obtained. The crossing plate 4 is an example of an obstruction that may be present in a predetermined vicinity of the on-board coil 13 and that obstructs normal failure detection of the electric power wave transmission circuit 10 by the electric power wave monitor 113a.

[0023] To check whether a drop in the power wave level is detected as a fault, a test is performed by actually lowering the power wave level. This can be confirmed by checking that the power wave monitor signal 117a is less than the power wave lower limit threshold 55 when the power wave output level control signal 116 is set to a predetermined intensity 54. Also, if the monitor value 56 of the power wave monitor signal 117a is equal to or greater than the power wave lower limit threshold 55 when the power wave output level control signal 116 is set to the power wave output level setting value 53 during normal operation, it can be confirmed that the power wave output characteristic 51 is normal. The health check of the power wave monitor 113a is performed by changing the power wave level setting value, so it is necessary to perform the check before the operation of the device immediately after the device is started up.

[0024] When the ground coil 3 or the crossing plate 4 is present near the on-board coil 13, the power wave output characteristic 52 appears, which does not match the power wave output characteristic 51 in normal operation, and the soundness of the power wave monitor 113a cannot be confirmed. That is, it is confirmed that the power wave output characteristic 52 based on the level of the power wave monitor signal 117a when the power wave output level control signal 116 is set to a predetermined intensity 54 and the level of the power wave monitor signal 117a when the power wave output level control signal 116 is set to the power wave output level setting value 53 in normal operation differs from the power wave output characteristic 51 in normal operation.

[0025] For this reason, the electric power wave transmission circuit 10 is connected to a dummy load 14 to check the soundness of the electric power wave monitor signal 117a, and after the soundness check is completed, the load is switched to the on-board coil 13. If the on-board coil 13 is located directly above the ground coil 3 or the crossing plate 4, switching the load of the electric power wave transmission circuit 10 to the on-board coil 13 may output a fault detection signal 115, which is avoided by the following method.

[0026] When the on-board coil 13 is directly above the ground coil 3, the power wave transmitted by the on-board coil 13 activates the ground coil 3 and transmits an information wave. When the information wave receiving unit 15 detects the information wave, it transmits information wave detection information and an information wave telegram to the control unit 2. When the control unit 2 receives the information wave detection information, it disables the output of the failure detection signal 115 to prevent a failure determination. When the vehicle starts moving, it leaves the ground coil 3 and is no longer able to receive the information wave, so the information wave detection signal stops, and the control unit 2 enables the output of the disabled failure detection signal 115, thereby resuming failure diagnosis of the electric power wave transmission circuit 10 based on the electric power wave output by the electric power wave transmission circuit 10.

[0027] When the on-board terminal 13 is directly above the gangway 4, the speed information 21 input to the control unit 2 is used to disable the output of the failure detection signal 115 when the vehicle is stopped, preventing a failure determination. When the vehicle starts to move and detects that it has traveled a predetermined distance, the control unit 2 enables the output of the failure detection signal 115 that was disabled, thereby resuming failure diagnosis of the electric power wave transmission circuit 10 based on the electric power wave output by the electric power wave transmission circuit 10.

[0028] Fig. 5 is a diagram for explaining the travel distance when disabling of the output of the power wave fault detection signal when the on-board device is activated immediately above the gangway is released. Fig. 5 shows the relative positional relationship of the on-board coils 13a, 13b and the gangway 4 in the traveling direction of the vehicle (left and right direction on the paper) and the vertical direction (up and down direction on the paper).

[0029] The control unit 2 of the on-board communication device 1 disables the output of the failure detection signal 115 when the on-board terminal 13 is located from the position of the on-board terminal 13a near the crossing board 4 to the position of the on-board terminal 13b. Since the control unit 2 cannot detect the positional relationship between the on-board terminal 13 and the crossing board 4, it is sufficient to use the movement distance from the position of the on-board terminal 13a, which is affected by the crossing board 4, to the position of the on-board terminal 13b to cancel the failure detection signal 115.

[0030] Specifically, if the length 113 of the on-board coil 13 in the vehicle travel direction is L1 and the length 41 of the crossing plank 4 in the vehicle travel direction is L2, the distance 134 at which the disablement of the output of the power wave fault detection signal is released is expressed as L1+L2. Therefore, when the travel distance calculated from the speed information 21 after the output of the fault detection signal 115 is disabled exceeds the previously registered L1+L2, the control unit 2 releases the disablement of the output of the fault detection signal 115 (i.e., enables the output of the fault detection signal 115), thereby making it possible to prevent erroneous fault detection and transition to operation.

[0031] [Embodiment 2] Fig. 6 is a diagram showing an example of the configuration of an on-board communication device 1B according to embodiment 2. The configuration of the on-board communication device 1B is the same as that of the on-board communication device 1 (Fig. 2) of embodiment 1, except that it has an output control unit 11B instead of the output control unit 11. The output control unit 11B further includes a power wave monitor 113b for detecting a power wave level between the load switching circuit 12 and the dummy load 14, an A / D converter 112b, and a power wave monitor signal 117b.

[0032] When the load switching circuit 12 is normal and the dummy load 14 is selected as the load of the power wave transmitting circuit 10, the output of the power wave transmitting circuit 10 is entirely supplied to the dummy load 14, so the power wave monitor signal 117a and the power wave monitor signal 117b match. Also, when the on-board coil 13 is selected as the load of the power wave transmitting circuit 10, the output of the power wave transmitting circuit 10 is not supplied to the dummy load 14, so the power wave monitor signal 117b is zero. In these cases, the control unit 2 diagnoses that the load switching circuit 12 is normal.

[0033] In addition, if the contacts of the load switching circuit 12 are stuck and both the on-board terminal 13 and the dummy load 14 are connected as loads to the power wave transmission circuit 10, the power wave monitor signal 117b will not match the power wave monitor signal 117a and will not become zero, which can be detected as an abnormality. In this case, the control unit 2 diagnoses the load switching circuit 12 as being faulty (stuck in connection to both the on-board terminal 13 and the dummy load 14).

[0034] Similarly, if all of the contacts of the load switching circuit 12 are in poor contact, the power wave monitor signal 117a does not reach the specified level, and this can be detected. At this time, the control unit 2 diagnoses the load switching circuit 12 as being faulty (all of the contacts between the on-board unit 13 and the dummy load 14 are in poor contact).

[0035] According to the above-described embodiment, when the vehicle is started, such as when it leaves the vehicle depot, the load of the electric power wave transmission circuit 10 is connected to the dummy load 14 when the on-board communication devices 1, 1B are started. This prevents the load impedance of the electric power wave transmission circuit 10 from fluctuating even if the ground coil 3 or the crossing plate 4 is present near the on-board coil 13, and allows the self-diagnosis of the electric power wave monitor 113a to be performed under stable conditions. This makes it possible to prevent erroneous detection of a failure due to the influence of the ground coil 3 or the crossing plate 4, even when the on-board communication devices 1, 1B are functioning normally.

[0036] The variable attenuator 103, the power wave monitors 113a and 113b, the A / D converters 112a and 112b, and the D / A converter 114 are one of the means for realizing the above-mentioned embodiment, and the above-mentioned embodiment does not limit these configurations. For example, the power wave level may be controlled using a variable amplifier instead of the variable attenuator 103, or the power wave voltage may be divided and input to the D / A converter 114 without passing through the power wave monitor 113a.

[0037] In addition, the preamplifier 102, the output stage amplifier 104, the low-pass filter 105, and the transformer 16 are not essential components for the above-mentioned embodiment, and may be deleted if unnecessary. In addition to the components shown in Fig. 2 and Fig. 6, a signal conversion circuit, a filter, etc. may be added as necessary.

[0038] Furthermore, the load switching circuit 12 may be controlled by the control unit 2 instead of the power wave control unit 111 .

[0039] The disclosed technology is not limited to the above-described embodiment, and various changes and modifications are possible by those skilled in the art within the scope of the technical ideas disclosed in this application, and various modified examples are included. In addition, the above-described embodiment is an example given to easily explain the disclosed technology, and is not necessarily limited to those having all the configurations described. In addition, it is possible to add, replace, or delete a part of the configuration of the above-described embodiment with the configuration of another embodiment or modified example. [Explanation of symbols]

[0040] 1, 1B: on-board communication device, 2: control unit, 3: ground coil, 4: gangway, 10: power wave transmitting circuit, 11: output control unit, 12: load switching circuit, 13, 13a, 13b: on-board coil, 14: dummy load, 15: information wave receiving unit.

Claims

1. An on-board communication device mounted on a vehicle traveling on a railroad track, an on-board coil that transmits power waves to a ground coil installed on the track and receives information waves from the ground coil; an information wave receiving unit that transmits data obtained by demodulating the information wave received by the on-board unit to a control unit; a power wave transmission circuit for transmitting a power wave to the on-board coil in accordance with a power wave transmission instruction output from the control unit; a power wave monitor that outputs a power wave monitor signal based on a power wave level of the power wave transmission circuit; a control unit that performs a health diagnosis of the power wave monitor based on the power wave monitor signal, A simulated load having an impedance equivalent to the on-board coil; a load switching circuit that switches the connection destination of the power wave transmission circuit between the on-board coil and the dummy load; An on-board communication device comprising:

2. The on-board communication device according to claim 1, a second power wave monitor that outputs a second power wave monitor signal based on a power wave level between the load switching circuit and the dummy load; The control unit is An on-board communication device characterized in that a fault in the load switching circuit is detected based on the power wave monitor signal and the second power wave monitor signal.

3. The on-board communication device according to claim 2, The control unit is When the electric power wave monitor signal and the second electric power wave monitor signal match, the load switching circuit is diagnosed as normal; When the power wave monitor signal and the second power wave monitor signal do not match and do not become zero, the load switching circuit diagnoses a fault in connection with both the on-board unit and the dummy load; An on-board communication device characterized in that, when the power wave monitor signal and the second power wave monitor signal do not reach specified levels, the load switching circuit diagnoses a fault due to poor contact in the contacts of both the on-board device and the dummy load.

4. The on-board communication device according to any one of claims 1 to 3, The load switching circuit includes: When the on-board communication device is started, the power wave transmission circuit is connected to the dummy load; An on-board communication device characterized in that, after the health diagnosis is completed, the connection destination of the power wave transmission circuit is switched from the dummy load to the on-board terminal.

5. The on-board communication device according to claim 4, The control unit is An on-board communication device characterized in that the power wave monitor is diagnosed as normal when a power wave output characteristic based on a first value where the level of the power wave monitor signal detected by the power wave monitor when the power wave level of the power wave transmission circuit is set to a first predetermined intensity is less than a threshold value, and a second value where the level of the power wave monitor signal detected by the power wave monitor when the power wave level is set to a second predetermined intensity greater than the first predetermined intensity is equal to or greater than the threshold value, matches a power wave output characteristic under normal conditions.

6. The on-board communication device according to claim 4 or 5, The control unit is after the health diagnosis is completed, when a fault is detected in the electric power wave transmission circuit when the connection destination of the electric power wave transmission circuit is switched from the dummy load to the on-board unit, output of a fault detection signal indicating a fault in the electric power wave transmission circuit is disabled; An on-board communication device characterized in that after detecting that the vehicle has traveled a predetermined distance based on speed information input to the control unit, output of the failure detection signal is enabled.

7. The on-board communication device according to claim 6, An on-board communication device characterized in that the specified distance is determined based on the sum of the lengths in the direction of travel of the vehicle of the on-board unit and an obstacle that may be present in a specified vicinity of the on-board unit and that may prevent the power wave monitor from properly detecting a fault in the power wave transmitting circuit.

8. A self-diagnosis method performed by an on-board communication device mounted on a vehicle traveling on a railroad track, comprising: The on-board communication device includes: an on-board coil that transmits power waves to a ground coil installed on the track and receives information waves from the ground coil; an information wave receiving unit that transmits data obtained by demodulating the information wave received by the on-board unit to a control unit; a power wave transmission circuit for transmitting a power wave to the on-board coil in accordance with a power wave transmission instruction output from the control unit; a power wave monitor that outputs a power wave monitor signal based on a power wave level of the power wave transmission circuit; a control unit that performs a health diagnosis of the power wave monitor based on the power wave monitor signal; A simulated load having an impedance equivalent to the on-board coil; a load switching circuit for switching a connection destination of the power wave transmission circuit from the on-board coil to the dummy load, The load switching circuit, connecting the electric power wave transmitting circuit to the dummy load in order to perform a health diagnosis of the electric power wave monitor; After the health diagnosis is completed, the connection destination of the power wave transmission circuit is switched from the dummy load to the on-board coil. A self-diagnosis method for an on-board communication device comprising:

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