JP2019118201A - Arc discharge determination device - Google Patents

Abstract

To determine whether or not arc discharge is generated between a pantagraph and an overhead power line even if an ultraviolet ray of the sunlight is made incident in a camera.SOLUTION: An arc discharge determination device of the embodiment comprises an imaging part, a high luminance region extraction part and an arc generation determination part. The imaging part is mounted on a vehicle, and receives a visible light ray from the periphery of a pantagraph of the vehicle. The high luminance region extraction part extracts a high luminance region of higher luminance than preset luminance in a visible light image provided by imaging of the imaging part. The arc generation determination part determines whether or not arc discharge is generated between the pantagraph and an overhead power line based on whether or not the area of the high luminance region is a first threshold value or more.SELECTED DRAWING: Figure 2

Description

  Embodiments of the present invention relate to an arc discharge determination device.

  There is a technique of imaging an arc discharge generated between a pantograph and an overhead wire using an ultraviolet camera. Also, using the detection result of the brightness of the contact point between the ground plate and the overhead wire and the detection result of the brightness around the pantograph by the illuminance sensor, it is determined whether or not arcing has occurred between the pantograph and the overhead wire Have the technology to

Patent No. 3793928 gazette JP, 2010-122102, A Patent No. 4415330

  However, in the technology of imaging an arc discharge using an ultraviolet camera, it is necessary to use a special ultraviolet camera. In addition, the technology that determines whether or not arcing has occurred using the detection result of the brightness of the contact point between the ground plate and the overhead wire and the detection result of the brightness around the pantograph by the illuminance sensor When sunlight is incident on the visible light camera used to detect the brightness of the contact point between the plate and the overhead wire, there is a possibility that the occurrence of arc discharge may be erroneously determined.

  The arc discharge determination apparatus according to the embodiment includes an imaging unit, a high brightness area extraction unit, and an arc occurrence determination unit. The imaging unit is mounted on the vehicle and receives visible light from the periphery of the pantograph of the vehicle. The high brightness area extraction unit extracts a high brightness area having a brightness higher than a preset brightness in a visible light image obtained by imaging by the imaging unit. The arc occurrence determination unit determines whether or not an arc discharge has occurred between the pantograph and the overhead wire based on whether or not the area of the high luminance region is equal to or greater than the first threshold.

FIG. 1 is a diagram showing an example of a configuration of an arc discharge determination device mounted on a vehicle according to a first embodiment. FIG. 2 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the first embodiment. FIG. 3 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the first embodiment. FIG. 4 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the first modification. FIG. 5 is a flowchart showing an example of the flow of arc generation determination processing by the image processing apparatus according to the first modification. FIG. 6 is a diagram for explaining an example of calculation processing of the arc discharge occurrence frequency in the image processing apparatus according to the first modification. FIG. 7 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the second embodiment. FIG. 8 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the second embodiment. FIG. 9 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the second modification. FIG. 10 is a flowchart illustrating an example of the flow of arc generation determination processing by the image processing apparatus according to the second modification. FIG. 11 is a diagram for explaining an example of arc generation determination processing by the image processing apparatus according to the second modification. FIG. 12 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the third modification. FIG. 13 is a flowchart illustrating an example of the flow of arc generation determination processing by the image processing apparatus according to the third modification. FIG. 14 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the fourth modification. FIG. 15 is a flowchart illustrating an example of the flow of arc generation determination processing in the image processing apparatus according to the fourth modification. FIG. 16 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the third embodiment. FIG. 17 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the third embodiment. FIG. 18 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the fourth embodiment. FIG. 19 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the fourth embodiment.

  Hereinafter, vehicles, such as an electric car to which an arc discharge judging device concerning this embodiment is applied, are explained using an attached drawing.

First Embodiment
FIG. 1 is a diagram showing an example of a configuration of an arc discharge determination device mounted on a vehicle according to a first embodiment. An example of a schematic configuration of the arc discharge determination device mounted on a vehicle according to the present embodiment will be described using FIG. 1. In the present embodiment, the arc discharge determination device includes a camera 101, an image processing device 102, a log recording device 103, and an in-vehicle monitor 104. In the present embodiment, the arc discharge determination device has the log recording device 103 and the in-vehicle monitor 104, but it may have at least the camera 101 and the image processing device 102.

  The camera 101 (an example of an imaging unit) is a camera capable of capturing visible light (so-called visible light camera) or the like, is mounted on a vehicle, and can capture the pantograph 2 of the vehicle. Specifically, the camera 101 receives visible light from the periphery of the pantograph 2 of the vehicle and captures an image of the pantograph 2. In the present embodiment, the camera 101 is provided so as to be able to image the pantograph 2 from below. Furthermore, in the present embodiment, the camera 101 is provided in front of the pantograph 2 in the traveling direction of the vehicle, but the present invention is not limited to this. The camera 101 is provided behind the pantograph 2 in the traveling direction of the vehicle. It may be done.

  The image processing apparatus 102 determines whether or not an arc discharge has occurred between the pantograph 2 and the overhead wire L based on a visible light image obtained by imaging the pantograph 2 with the camera 101. Then, the image processing apparatus 102 stores the determination result as to whether or not the arc discharge has occurred in the log recording apparatus 103. The log recording device 103 is an HDD (Hard Disk Drive) or the like, and is a storage unit that stores various information such as the determination result of whether or not arc discharge has occurred. In the present embodiment, the log recording device 103 determines whether or not arc discharge has occurred between the pantograph 2 and the overhead wire L as a result of determination as to whether or not arc discharge has occurred (that is, a visible light image is obtained). And the like, and stores the determination result together with identifiable information. In the present embodiment, the image processing apparatus 102 stores the arc discharge determination result with respect to the log recording apparatus 103 mounted on the vehicle, but the present invention is not limited to this. For example, the result of determination as to whether or not arcing has occurred may be stored in the storage device of the system on the ground side.

  The in-vehicle monitor 104 is an LCD (Liquid Crystal Display) or the like, and is a display unit that displays various information such as a determination result as to whether or not an arc discharge has occurred. In the present embodiment, the image processing apparatus 102 causes the in-vehicle monitor 104 mounted on the vehicle to display the determination result as to whether or not arcing has occurred. However, the present invention is not limited to this. The arc discharge determination result may be displayed on an external display device (e.g., a display unit of a system on the ground side).

  FIG. 2 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the first embodiment. FIG. 3 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the first embodiment. Next, an example of the flow of arc generation determination processing in the image processing apparatus 102 according to the present embodiment will be described using FIGS. 2 and 3. In the present embodiment, as shown in FIG. 2, the image processing apparatus 102 includes an image acquisition unit 201, a high brightness area extraction unit 202, a high brightness area area calculation unit 203, and an arc occurrence determination unit 204.

  The image acquiring unit 201 acquires, from the camera 101, a visible light image obtained by imaging the pantograph 2 by the camera 101 (step S301). In the visible light image acquired by the image acquisition unit 201, the high luminance area extraction unit 202 extracts an area having a luminance higher than that set in advance (hereinafter, referred to as a high luminance area) (step S302). Here, the preset brightness is the brightness of the visible light image when the arc discharge occurs between the overhead line L and the pantograph 2. Arc light generated by arc discharge has high brightness. Therefore, when the pixel value of the visible light image can be 0 to 255, the pixel value of the visible light image when arc light is generated is often 255. Therefore, in the present embodiment, the high luminance area extraction unit 202 extracts an area constituted by pixels whose pixel value is 255 in the visible light image as a high luminance area.

  The high brightness area area calculation unit 203 calculates the area of the high brightness area extracted by the high brightness area extraction unit 202 (step S303). In the present embodiment, the high brightness area area calculation unit 203 counts the number of pixels in the high brightness area, and calculates the value obtained by multiplying the counted number of pixels by the area per pixel as the area of the high brightness area. Do. The arc occurrence determination unit 204 determines whether an arc discharge has occurred between the pantograph 2 and the overhead wire L based on whether the area of the high brightness area calculated by the high brightness area area calculation unit 203 is equal to or larger than the threshold TH1. It is determined (step S304). In the present embodiment, the arc generation determination unit 204 determines that an arc discharge has occurred between the pantograph 2 and the overhead wire L when the area of the high luminance region is equal to or larger than the threshold TH1.

  As described above, according to the arc discharge determination apparatus according to the first embodiment, the occurrence of arc discharge between the pantograph 2 and the overhead wire L can be detected without using the ultraviolet camera. Even if the light is incident, it can be determined whether or not an arc discharge has occurred between the pantograph 2 and the overhead wire L. Further, since the occurrence of arc discharge between the pantograph 2 and the overhead wire L can be detected without using a special ultraviolet camera or a plurality of cameras, the cost required to realize the arc discharge determination device can be reduced.

(Modification 1)
In this modification, the frequency of occurrence of arc discharge between the pantograph and the overhead wire is determined using a visible light image, and whether or not arc discharge has occurred between the pantograph and the overhead wire based on the frequency of occurrence of the arc discharge. It is an example of determination. In the following description, the description of the same configuration as that of the first embodiment is omitted.

  FIG. 4 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the first modification. FIG. 5 is a flowchart showing an example of the flow of arc generation determination processing by the image processing apparatus according to the first modification. FIG. 6 is a diagram for explaining an example of calculation processing of the arc discharge occurrence frequency in the image processing apparatus according to the first modification. The flow of the arc generation determination process by each part of the image processing apparatus 400 according to the present modification will be described with reference to FIGS. The processing from step S301 to step S303 in FIG. 5 is the same as that in the first embodiment. Further, in the present modification, as illustrated in FIG. 4, the image processing apparatus 400 includes an image acquisition unit 201, a high brightness area extraction unit 202, a high brightness area area calculation unit 203, and an arc occurrence determination unit 401. Further, the arc occurrence determination unit 401 includes a first arc occurrence determination unit 402, an arc occurrence frequency calculation unit 403, and a second arc occurrence determination unit 404.

  The first arc occurrence determining unit 402 executes a first arc occurrence determining process of determining whether the area of the high luminance region is equal to or greater than the threshold TH1 (step S501). The arc occurrence frequency calculation unit 403 calculates the occurrence frequency of the arc discharge between the pantograph 2 and the overhead wire L (hereinafter referred to as the arc discharge occurrence frequency) (step S502). Specifically, as shown in FIG. 6, among the N visible light images obtained within a preset time, the arc occurrence frequency calculation unit 403 determines that a visible light image is determined to have generated an arc discharge. Count the number of (A sheet). Next, the arc occurrence frequency calculation unit 403 determines the ratio (A / A) of the visible light images of the A sheet determined to cause the arc discharge to the number (N sheets) of visible light images obtained within a preset time. N) is calculated as the arc discharge occurrence frequency R. Here, the visible light image determined to have generated an arc discharge is a visible light image determined to have the area of the high luminance region equal to or greater than the threshold TH1. Alternatively, as illustrated in FIG. 6, the arc occurrence frequency calculation unit 403 determines the ratio of the visible light images of A sheets determined to have generated the arc discharge among the visible light images of the preset frame number N (A Calculate / N) as the arc discharge occurrence frequency R.

  Returning to FIG. 5, the second arc occurrence determining unit 404 determines that an arc occurs between the pantograph 2 and the overhead wire L when the arc occurrence frequency calculated by the arc occurrence frequency calculating unit 403 is equal to or greater than the threshold TH1a. The second arc occurrence determination processing is executed (step S503). Here, the threshold value TH1a is the lower limit of the arc discharge occurrence frequency that determines that arc discharge has occurred between the pantograph 2 and the overhead wire L. Thus, when the area of the high-brightness region included in the visible light image becomes equal to or greater than the threshold TH1 due to an influence other than the arc discharge generated between the pantograph 2 and the overhead wire L, an arc discharge is generated between the pantograph 2 and the overhead wire L It is possible to prevent the wrong judgment of things.

  In the present modification, the second arc occurrence determining unit 404 determines that arcing has occurred between the pantograph 2 and the overhead wire L when the arc occurrence frequency is equal to or higher than the threshold TH1a, but this is limited to this It is not a thing. For example, the second arc generation determination unit 404 may determine that arc discharge has occurred between the pantograph 2 and the overhead wire L when the arc discharge frequency is within a predetermined arc discharge frequency range. Here, the predetermined arc discharge occurrence frequency range is a range of the arc discharge occurrence frequency that determines that arc discharge has occurred between the pantograph 2 and the overhead wire L. In the present modification, the predetermined arc discharge occurrence frequency range is equal to or higher than the threshold TH1a and equal to or lower than the threshold TH1b. Here, the threshold value TH1 b is the upper limit of the arc discharge occurrence frequency that determines that arc discharge has occurred between the pantograph 2 and the overhead wire L.

  In the daytime, when the sunlight is directed to the camera 101 or the vehicle comes out from the tunnel, the visible light image has white spots while the control of the exposure of the camera 101 is completed by the automatic exposure control. It often occurs. Also in this case, since a high luminance region continues to be generated in the visible light image (that is, since the arc discharge occurrence frequency continues to be 1.0), the occurrence of the arc discharge may be erroneously determined. Therefore, in the present modification, an upper limit (threshold TH1 b) is added to the range of arc discharge occurrence frequency in which it is determined that arc discharge has occurred. As a result, it takes time for the automatic exposure control of the camera 101 when the sunlight is exposed to the camera 101 in the daytime or when the vehicle comes out from the tunnel during the daytime, and the overexposure of the visible light image continues. Even when the frequency of occurrence of discharge increases, it is possible to prevent an erroneous determination of the occurrence of arc discharge.

  As described above, according to the arc discharge determination apparatus according to the first modification, when the area of the high luminance region included in the visible light image becomes equal to or more than the threshold TH1 due to influences other than the arc discharge generated between the pantograph 2 and the overhead wire L. In addition, it is possible to prevent the erroneous determination of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L.

Second Embodiment
The present embodiment is an example of determining whether or not an arc discharge has occurred between the pantograph and the overhead wire, using the amount of change in the area of the high luminance region included in the visible light image obtained by the camera at different times. In the following description, the description of the same configuration as that of the above-described embodiment will be omitted.

  FIG. 7 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the second embodiment. FIG. 8 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the second embodiment. The flow of the arc generation determination process by each unit of the image processing apparatus 700 according to the present embodiment will be described with reference to FIGS. 7 and 8. The process from step S301 to step S302 in FIG. 8 is the same as that in the first embodiment. As shown in FIG. 7, the image processing apparatus 700 according to the present embodiment includes an image acquisition unit 201, a high luminance area extraction unit 202, an area change amount calculation unit 701, and an arc occurrence determination unit 702.

  The area change amount calculation unit 701 uses the area S0 of the high-luminance area included in the visible light image (for example, the immediately preceding frame) obtained at a preset time (an example of the first time) to be the latest visible. An area change amount D (= | S1−S0 |) which is a change amount of the area S1 of the high luminance region included in the light image (an example of the visible light image obtained at the second time) is calculated (step S801). In the present embodiment, the area change amount calculation unit 701 calculates the absolute value of the value obtained by subtracting the area S0 from the area S1 as the area change amount D, but the area of the high luminance region included in the visible light image is increased. Only in the case (that is, only when the value obtained by subtracting the area S0 from the area S1 is a positive number), it may be determined whether the arc discharge has occurred using the area change amount D.

  Arc generation determination unit 702 determines whether arc discharge has occurred between Pantab Rough 2 and overhead wire L based on whether area change amount D calculated by area change amount calculation unit 701 is equal to or larger than threshold value TH2. An arc determination process to determine is performed (step S802). The arc discharge generated between the pantograph 2 and the overhead wire L has a high luminance and changes the area of the high luminance region included in the visible light image with time (because the visible light image looks like it is blinking), so the area change The amount D becomes large. On the other hand, when sunlight enters the imaging range of the camera 101 and a high brightness area is continuously generated in the visible light image, blinking of the visible light image does not occur, and the area change amount D is a threshold The value is smaller than TH2. Also, when the vehicle leaves the tunnel, overexposure often occurs in the visible light image until the exposure control of the camera 101 is completed by the automatic exposure control. Also in that case, as in the case where sunlight enters the imaging range of the camera 101, a high brightness area continues to be generated in the visible light image, and the area change amount D becomes a value smaller than the threshold TH2.

  Therefore, in the present embodiment, when the area change amount D is equal to or greater than the threshold value TH2, the arc occurrence determination unit 702 determines that arcing has occurred. Thus, when a high brightness area is generated in the visible light image due to a factor other than the arc discharge between the pantograph 2 and the overhead wire L, it is possible to prevent the erroneous determination that the arc discharge is generated. It is possible to improve the determination accuracy as to whether or not arc discharge has occurred between the overhead wires L.

  As described above, according to the image processing apparatus 700 according to the second embodiment, it is possible to improve the determination accuracy as to whether or not the arc discharge has occurred between the pantograph 2 and the overhead wire L.

  In the present embodiment, the arc occurrence determination unit 702 determines whether or not arc discharge has occurred between the pantograph 2 and the overhead wire L using a visible light image obtained by imaging by one camera 101. The present invention is not limited to this, and visible light images obtained by imaging a plurality of cameras 101 (for example, the camera 101 provided in front of the pantograph 2 and the camera 101 provided behind the pantograph 2 in the traveling direction of the vehicle) It may be used to determine whether or not arcing has occurred between the pantograph 2 and the overhead wire L.

  Specifically, the arc generation determination unit 702 sequentially changes the area change amount D of the high-brightness region included in the visible light image from the visible light image obtained first among the visible light images obtained by imaging of the plurality of cameras 101. It is determined whether arcing has occurred between the pantograph 2 and the overhead wire L based on whether or not the threshold value TH2 is equal to or greater than the threshold value TH2. As a result, the time resolution of the process of determining whether or not arcing has occurred can be enhanced, so that the occurrence of arcing occurring in a shorter time can be detected.

(Modification 2)
In this modification, the arc discharge occurrence frequency is calculated using the area change amount of the high luminance region included in the visible light image, and based on the arc discharge occurrence frequency, whether the arc discharge has occurred between the pantograph and the overhead wire Is an example of determining In the following description, the description of the same configuration as that of the second embodiment will be omitted.

  FIG. 9 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the second modification. FIG. 10 is a flowchart illustrating an example of the flow of arc generation determination processing by the image processing apparatus according to the second modification. FIG. 11 is a diagram for explaining an example of arc generation determination processing by the image processing apparatus according to the second modification. The flow of the arc generation determination process by each part of the image processing apparatus 900 according to the present modification will be described with reference to FIGS. 9 to 11. The process from step S301 to step S801 in FIG. 10 is the same as that in the second embodiment. In the present modification, as shown in FIG. 9, the image processing apparatus 900 includes an image acquisition unit 201, a high brightness area extraction unit 202, an area change amount calculation unit 701, and an arc occurrence determination unit 901. The arc generation determination unit 901 includes a first arc generation determination unit 902, an arc generation frequency calculation unit 903, and a second arc generation determination unit 904.

  The first arc occurrence determining unit 902 executes a first arc occurrence determining process of determining whether the area change amount D is equal to or larger than the threshold TH2 (step S1001). The arc occurrence frequency calculation unit 903 calculates, as an arc discharge occurrence frequency, a ratio of visible light images determined to have generated arc discharge among visible light images of a preset number of frames (step S1002). Here, the visible light image determined to have generated an arc discharge is a visible light image in which the area change amount D is equal to or greater than the threshold TH2. Specifically, as shown in FIG. 11, the arc occurrence frequency calculation unit 903 determines the number of visible light images determined to be arc discharge out of the visible light images of the preset frame number N (A Count). Next, the arc occurrence frequency calculation unit 903 generates an arc discharge (A / N) as a ratio of the number (A sheet) of visible light images determined to cause arc discharge to the preset frame number N. Calculated as frequency R. Alternatively, the arc discharge occurrence frequency calculation unit 903 may calculate, as the arc discharge occurrence frequency R, the proportion of the time in which the visible light image in which the arc discharge is determined to be generated is obtained among the preset times.

  Referring back to FIG. 10, the second arc occurrence determining unit 904 determines that an arc occurs between the pantograph 2 and the overhead wire L when the arc occurrence frequency calculated by the arc occurrence frequency calculating unit 903 is equal to or higher than the threshold TH2a. The second arc occurrence determination processing to be determined is executed (step S1003). Here, the threshold value TH2a is the lower limit of the arc discharge occurrence frequency R that determines that arc discharge has occurred between the pantograph 2 and the overhead wire L. Thus, when the area change amount D temporarily exceeds the threshold value TH2 due to an influence (for example, noise included in the visible light image) other than the arc discharge generated between the pantograph 2 and the overhead wire L, the pantograph 2 and the overhead wire Since it is possible to prevent an erroneous determination that an arc discharge has occurred between L, the determination accuracy of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L can be improved.

  As described above, according to the image processing apparatus 900 according to the second modification, it is possible to improve the determination accuracy as to whether or not the arc discharge has occurred between the pantograph 2 and the overhead wire L.

(Modification 3)
The present modification is an example in which a time interval in which the area change amount is large is calculated, and it is determined that an arc discharge has occurred between the pantograph and the overhead wire when the calculation result of the time interval is large. In the following description, the description of the same configuration as that of the second embodiment will be omitted.

  FIG. 12 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the third modification. FIG. 13 is a flowchart illustrating an example of the flow of arc generation determination processing by the image processing apparatus according to the third modification. The flow of arc generation determination processing by the image processing apparatus 1200 according to the present modification will be described with reference to FIGS. 12 and 13. The process from step S301 to step S801 in FIG. 13 is the same as that in the second embodiment. The image processing apparatus 1200 according to the present modification includes an image acquisition unit 201, a high luminance area extraction unit 202, an area change amount calculation unit 701, and an arc occurrence determination unit 1201, as shown in FIG. The arc generation determination unit 1201 has a first arc generation determination unit 1202, an arc generation interval calculation unit 1203, a diversity calculation unit 1204, and a second arc generation determination unit 1205.

  The first arc occurrence determining unit 1202 executes a first arc occurrence determining process of determining whether the area change amount D is equal to or larger than the threshold TH2 (step S1301). The arc generation interval calculation unit 1203 calculates, as an arc generation interval, a time interval at which the area change amount D is equal to or larger than the threshold value TH2 (step S1302). Specifically, the arc generation interval calculation unit 1203 calculates the X-th arc at the time IX when the latest visible light image determined to have the possibility of arc discharge being generated and the X-1st arc. An arc generation interval T1 (= IX-IX1) of time IX1 at which a visible light image determined to have the possibility of occurrence of discharge is obtained is determined. Here, the visible light image determined to have the possibility that arc discharge has occurred is a visible light image in which the area change amount D is equal to or greater than the threshold TH2. In addition, the arc generation interval calculation unit 1203 calculates an arc generation interval T2 between time IX1 and time IX2 at which the visible light image determined to have the possibility of arc discharge at the X-2nd position is obtained. Find (= IX1-IX2). Thus, the arc generation interval calculation unit 1203 obtains a plurality of arc generation intervals T (= T1, T2,..., TN).

  The diversity calculation unit 1204 calculates the diversity V of the plurality of arc generation intervals T (= T1, T2,..., TN) thus determined (step S1303). For example, the diversity calculation unit 1204 calculates the standard deviation of the plurality of arc generation intervals T obtained as the diversity V of the plurality of arc generation intervals T. The second arc occurrence determination unit 1205 determines that an arc discharge has occurred between the pantograph 2 and the overhead wire L when the diversity V calculated by the diversity calculation unit 1204 is equal to or greater than the threshold TH 2 b. The process is executed (step S1304). The arc discharge between the pantograph 2 and the overhead wire L is likely to have a random occurrence interval. Also, even when the vehicle crosses an iron bridge in a state where sunlight is direct with respect to the camera 101, the pillars of the iron bridge block sunlight and an increase and decrease in area change amount D of a high luminance region included in a visible light image It is conceivable to repeat the However, when sunlight is blocked by the columns of the iron bridge, the area change amount D periodically repeats increase and decrease, so that the diversity of the arc generation intervals decreases.

  Therefore, in the present modification, the diversity calculation unit 1204 determines that an arc discharge has occurred between the pantograph 2 and the overhead wire L when the diversity V of the arc generation interval T is equal to or greater than the threshold TH2b. Thereby, when the area change amount D becomes large due to factors other than the arc discharge between the pantograph 2 and the overhead wire L (for example, shielding and non-shielding of sunlight by columns of iron bridge), an arc between the pantograph 2 and the overhead wire L Since the erroneous determination that the discharge has occurred can be prevented, the determination accuracy of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L can be improved.

  As described above, according to the image processing apparatus 1200 according to the third modification, the determination accuracy of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L can be improved.

(Modification 4)
The present modification is an example in which it is determined that an arc discharge has occurred between the pantograph and the overhead wire when the calculation result of the area change amount of the high luminance region included in the visible light image is highly diverse. In the following description, the description of the same configuration as that of the second embodiment will be omitted.

  FIG. 14 is a diagram illustrating an example of a functional configuration of the image processing apparatus according to the fourth modification. FIG. 15 is a flowchart illustrating an example of the flow of arc generation determination processing in the image processing apparatus according to the fourth modification. The flow of the arc generation determination process by each unit of the image processing apparatus 1400 according to the present modification will be described with reference to FIGS. 14 and 15. The process from step S301 to step S801 in FIG. 15 is the same as that in the second embodiment. In the present modification, as illustrated in FIG. 14, the image processing apparatus 1400 includes an image acquisition unit 201, a high luminance area extraction unit 202, an area change amount calculation unit 701, and an arc occurrence determination unit 1401. The arc occurrence determination unit 1401 includes a variation diversity calculation unit 1402 and an arc occurrence determination unit 1403.

  The variation diversity calculator 1402 calculates the diversity V of the area variation D calculated by the area variation calculator 701 (step S1501). For example, the variation diversity calculator 1402 calculates the standard deviation of the latest plurality of area variation D (= D1, D2,..., DN) as the diversity V of the area variation D. Then, the arc occurrence determination unit 1403 executes an arc occurrence determination process that determines that arc discharge has occurred between the pantograph 2 and the overhead wire L when the diversity V calculated by the variation diversity calculation unit 1402 is large. (Step S1502). In the present embodiment, the arc occurrence determination unit 1403 determines that an arc discharge has occurred between the pantograph 2 and the overhead wire L when the diversity V calculated by the variation diversity calculation unit 1402 is equal to or greater than the threshold TH2c. .

  The area of the high luminance region due to the occurrence of the arc discharge between the pantograph 2 and the overhead wire L often changes randomly, so the possibility that the variety V of the area change amount D becomes large is high. On the other hand, when the sunlight is blocked by the columns of the iron bridge when the vehicle passes the iron bridge in a state where the sunlight is direct to the camera 101, the area change amount D is often constant, so the diversity V is likely to be small. Therefore, in the present embodiment, the arc occurrence determination unit 1403 determines that an arc discharge has occurred between the pantograph 2 and the overhead wire L when the diversity V calculated by the variation diversity calculation unit 1402 is equal to or greater than the threshold TH2c. judge. Thereby, when the area change amount D becomes large due to factors other than the arc discharge between the pantograph 2 and the overhead wire L (for example, shielding and non-shielding of sunlight by columns of iron bridge), an arc between the pantograph 2 and the overhead wire L Since the erroneous determination that the discharge has occurred can be prevented, the determination accuracy of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L can be improved.

  As described above, according to the image processing apparatus 1400 according to the fourth modification, the determination accuracy of the occurrence of the arc discharge between the pantograph 2 and the overhead wire L can be improved.

Third Embodiment
The present embodiment is an example in which the threshold value of the area of the high luminance region determined to be arc discharge is determined based on the luminance of the visible light image determined to be arc discharge not occurring between the pantograph and the overhead wire. is there. In the following description, the description of the same configuration as that of the first embodiment is omitted.

  FIG. 16 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the third embodiment. FIG. 17 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the third embodiment. The flow of the arc generation determination process by each unit of the image processing apparatus 1600 according to the present embodiment will be described with reference to FIGS. 16 and 17. The process from step S301 to step S303 shown in FIG. 17 is the same as that of the first embodiment. In the present embodiment, as shown in FIG. 16, the image processing apparatus 1600 includes an image acquisition unit 201, a high brightness area extraction unit 202, a high brightness area area calculation unit 203, and an arc occurrence determination unit 1601. The arc generation determination unit 1601 includes an arc generation determination unit 1602 and an area threshold determination unit 1603.

  Arc generation determination unit 1602 executes arc generation determination processing to determine whether or not arc discharge has occurred between pantograph 2 and overhead wire L based on whether or not the area of the high luminance region is equal to or greater than threshold value TH1. (Step S1701). The area threshold value determination unit 1603 executes an area threshold value determination process of determining the threshold value TH1 based on the luminance of the visible light image determined by the arc occurrence determination unit 1602 that arc discharge has not occurred (step S1702). In the present embodiment, the area threshold value determination unit 1603 changes the threshold value TH1 based on the luminance of the visible light image when it is determined by the arc occurrence determination unit 1602 that no arc discharge has occurred. On the other hand, the area threshold value determination unit 1603 does not change the threshold value TH1 when the arc occurrence determination unit 1602 determines that the arc discharge is occurring.

  The average M of the luminance of the visible light image (hereinafter referred to as the average luminance) is less than the luminance M1 at night, and is more than the luminance M1 and less than the luminance M2 in the daytime. In the case of direct exposure, the luminance is M2 or more. Therefore, when it is determined that arcing has not occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the latest visible light image is equal to or lower than the luminance M1, the area threshold determination unit 1603 determines the threshold TH1. Among the threshold candidates that can be set as the threshold TH1, the largest threshold TH1-1 is determined.

  If it is determined that arcing has not occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the finally obtained visible light image is greater than M1 and less than M2, the area threshold value determination unit 1603 The threshold value TH1 is determined as the threshold value TH1-2 smaller than the threshold value TH1-1 among the threshold value candidates. Furthermore, when it is determined that arcing has not occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the finally obtained visible light image is equal to or higher than the luminance M2, the area threshold determination unit 1603 determines the threshold TH1. Among the threshold candidates, the threshold TH1-3 which is smaller than the threshold TH1-2 is determined.

  Here, the reason why the threshold TH1 is made smaller as the average luminance M becomes higher is that it occurs in the bright environment of daytime and in the dark environment such as nighttime even with arc discharge of the same intensity. This is because the area of the high luminance region included in the visible light image is different. Specifically, when an arc discharge occurs in a dark environment such as nighttime, the area of the high luminance region included in the visible light image becomes large, so the threshold TH1 is increased. On the other hand, when the arc discharge occurs in a bright environment during the daytime, the area of the high luminance region included in the visible light image decreases, so the threshold TH1 is reduced.

  Thereafter, when the area of the high luminance area included in the new visible light image is calculated by the high luminance area area calculation unit 203, the arc occurrence determination unit 1602 determines that the area of the high luminance area to be calculated is the area threshold determination unit 1603. It is determined whether or not arc discharge has occurred between the pantograph 2 and the overhead wire L based on whether or not it is the latest threshold value TH1 or more determined by the above. As a result, the threshold TH1 can be changed to a threshold that can appropriately determine whether or not arcing has occurred between the pantograph 2 and the overhead wire L according to the surrounding environment of the pantograph 2 and the overhead wire L. It is possible to improve the determination accuracy as to whether or not arcing has occurred between the wire L and the overhead wire L.

  In the present embodiment, the area threshold value determination unit 1603 determines the threshold value TH1 based on the average luminance M of the visible light image, but the present invention is not limited to this. The area of the high luminance area included in the visible light image The threshold TH1 may be determined according to For example, the area threshold value determination unit 1603 can determine that the area around the overhead line L and the pantograph 2 is darker as the area of the high luminance area included in the visible light image is larger. Therefore, as the area of the high luminance area increases, the threshold TH1 is increased. Enlarge.

  As described above, according to the image processing apparatus 1600 according to the third embodiment, it is possible to improve the determination accuracy as to whether or not the arc discharge has occurred between the pantograph 2 and the overhead wire L.

Fourth Embodiment
The present embodiment is an example of determining the threshold value of the area change amount that determines that the arc discharge has occurred, based on the luminance of the visible light image that has been determined that the arc discharge has not occurred between the pantograph and the overhead wire. In the following description, the description of the same configuration as that of the second embodiment will be omitted.

  FIG. 18 is a block diagram showing an example of the functional arrangement of an image processing apparatus according to the fourth embodiment. FIG. 19 is a flowchart showing an example of the flow of arc generation determination processing in the image processing apparatus according to the fourth embodiment. The flow of the arc generation determination process by each unit of the image processing apparatus 1800 according to the present embodiment will be described with reference to FIGS. 18 and 19. The processing from step S301 to step S801 in FIG. 19 is the same as that in the second embodiment. In the present embodiment, as shown in FIG. 18, the image processing apparatus 1800 includes an image acquisition unit 201, a high luminance area extraction unit 202, an area change amount calculation unit 701, and an arc occurrence determination unit 1801. The arc generation determination unit 1801 includes an arc generation determination unit 1802 and an area change amount threshold determination unit 1803.

  Arc generation determination unit 1802 executes arc generation determination processing to determine whether or not arc discharge has occurred between pantograph 2 and overhead wire L based on whether or not area change amount D is equal to or greater than threshold value TH (( Step S1901). The area change amount threshold value determination unit 1803 determines the threshold value TH2 based on the luminance of the visible light image determined by the arc generation determination unit 1802 to be not generating the arc discharge (step S1902). In the present embodiment, the area change amount threshold determination unit 1803 changes the threshold TH2 based on the luminance of the visible light image when it is determined by the arc occurrence determination unit 1802 that no arc discharge has occurred. On the other hand, the area change amount threshold value determination unit 1803 does not change the threshold value TH3 when it is determined by the arc occurrence determination unit 1802 that arc discharge is occurring.

  The average brightness M of the visible light image is less than the brightness M1 at night, less than the brightness M1 and more than the brightness M1 in the daytime, and less than the brightness M1. Become. Therefore, if it is determined that arcing has not occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the visible light image obtained last is less than or equal to the luminance M1, the area change amount threshold determination unit 1803 The threshold TH2 is determined to be the largest threshold TH2-1 among the threshold candidates that can be set to the threshold TH2.

  In addition, if it is determined that arcing has not occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the visible light image obtained last is greater than or equal to the luminance M1 and less than the luminance M2, the area change amount threshold determination is made. The unit 1803 determines the threshold TH2 to be a threshold TH2-2 smaller than the threshold TH2-1 among the threshold candidates. Furthermore, when it is determined that no arc discharge has occurred between the pantograph 2 and the overhead wire L, and the average luminance M of the visible light image obtained last is equal to or higher than the luminance M2, the area change amount threshold determination unit 1803 The threshold TH2 is determined to be a threshold TH2-3 smaller than the threshold TH2-2 among the threshold candidates.

  Here, the reason why the threshold TH2 is decreased as the average brightness M increases is that the arc discharge of the same intensity occurs in the daytime bright environment and in the dark environment such as the nighttime. This is because the area change amount D of the high luminance area included in the visible light image is different. Specifically, when the arc discharge occurs in a dark environment such as night, the area change amount D of the high luminance region included in the visible light image becomes large, so the threshold value TH2 is increased. On the other hand, when the arc discharge occurs in a bright environment during the daytime, the area change amount D of the high luminance region included in the visible light image decreases, so the threshold value TH2 is decreased.

  Thereafter, when the area change amount calculation unit 701 calculates the area change amount D of the high luminance region included in the new visible light image, the arc occurrence determination unit 1802 determines that the calculated area change amount D is the area change amount threshold. It is determined whether or not arc discharge has occurred between the pantograph 2 and the overhead line L based on whether or not it is equal to or more than the latest threshold value TH2 determined by the determination unit 1803. As a result, the threshold TH2 can be changed to a threshold that can appropriately determine whether or not arcing has occurred between the pantograph 2 and the overhead wire L, depending on the surrounding environment of the pantograph 2 and the overhead wire L. It is possible to improve the determination accuracy as to whether or not arcing has occurred between the wire L and the overhead wire L.

  In the present embodiment, the area change amount threshold determination unit 1803 determines the threshold TH2 based on the average luminance M of the visible light image, but the present invention is not limited to this, and a high luminance region included in the visible light image The threshold value TH2 may be determined according to the area change amount D of For example, the area change amount threshold determination unit 1803 can determine that the area around the pantograph 2 and the overhead line L is darker as the area change amount D in the high luminance area included in the visible light image is larger. As the increases, the threshold TH2 is increased.

  As described above, according to the image processing apparatus 1800 according to the fourth embodiment, it is possible to improve the determination accuracy as to whether or not the arc discharge has occurred between the pantograph 2 and the overhead wire L.

  As described above, according to the first to fourth embodiments, it is possible to determine whether or not arc discharge has occurred between the pantograph 2 and the overhead wire L even if ultraviolet rays of sunlight enter the camera 101. .

  The programs executed by the image processing apparatuses 102, 400, 700, 900, 1200, 1400, 1600, and 1800 of the present embodiment are provided by being incorporated in advance in a ROM (Read Only Memory) or the like.

  The programs executed by the image processing apparatuses 102, 400, 700, 900, 1200, 1400, 1600, and 1800 according to the present embodiment are files in an installable format or an executable format, such as a CD-ROM or a flexible disk (FD). It may be configured to be recorded and provided in a computer readable recording medium such as a CD-R, a DVD (Digital Versatile Disk), or the like.

  Furthermore, the program executed by the image processing apparatus 102, 400, 700, 900, 1200, 1400, 1600, and 1800 of the present embodiment is stored on a computer connected to a network such as the Internet and downloaded via the network. May be configured to provide. Further, the programs executed by the image processing apparatuses 102, 400, 700, 900, 1200, 1400, 1600, and 1800 of the present embodiment may be configured to be provided or distributed via a network such as the Internet.

  The programs executed by the image processing apparatuses 102, 400, 700, 900, 1200, 1400, 1600, and 1800 according to the present embodiment are the units described above (the image acquisition unit 201, the high luminance area extraction unit 202, and the high luminance area area calculation The module configuration includes an arc generation determination unit 204, 401, 702, 901, 1201, 1401, 1601, and 1801 and an area change amount calculation unit 701). As an actual hardware, a CPU (Central Processing Unit) Etc. are read from the ROM and executed to load the above units onto the main storage device, and the image acquisition unit 201, high brightness area extraction unit 202, high brightness area area calculation unit 203, arc occurrence determination Sections 204, 401, 702, 901, 1201, 1401, 1601, 1801, and so on. An area change amount calculation unit 701 is generated on the main storage device.

  While certain embodiments of the present invention have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

  2 ... pantograph, 101 ... camera, 102, 400, 700, 900, 1200, 1400, 1600, 1800 ... image processing device, 103 ... log recording device, 104 ... in-car monitor, 201 ... image acquisition unit, 202 ... high brightness area Extraction unit 203 High brightness area area calculation unit 204, 401, 702, 901, 1201, 1401, 1601, 1801 Arc generation determination unit 701, area change amount calculation unit

Claims (11)

An imaging unit mounted on a vehicle and receiving visible light from around the pantograph of the vehicle;
A high brightness area extraction section for extracting a high brightness area having a brightness higher than a preset brightness in a visible light image obtained by imaging of the imaging section;
An arc generation determination unit that determines whether or not arc discharge has occurred between the pantograph and the overhead wire based on whether or not the area of the high luminance region is equal to or greater than a first threshold value;
Arc discharge determination apparatus comprising:   The arc generation determination unit determines that the area of the high luminance region is equal to or more than the first threshold among a plurality of visible light images obtained within a preset time or a visible light image of a preset number of frames. The ratio of the visible light image that has become is calculated as the arc discharge occurrence frequency, and when the arc discharge occurrence frequency is equal to or higher than a second threshold, or when the arc discharge occurrence frequency is within a predetermined arc discharge occurrence frequency range, The arc discharge determination apparatus according to claim 1, wherein it is determined that arc discharge has occurred between the pantograph and the overhead wire. An imaging unit mounted on a vehicle and receiving visible light from around the pantograph of the vehicle;
A high brightness area extraction section for extracting a high brightness area having a brightness higher than a preset brightness in a visible light image obtained by imaging of the imaging section;
An amount of change in area of the high brightness area included in the visible light image obtained at a second time different from the first time, based on the area of the high brightness area included in the visible light image obtained at the first time A change amount calculation unit that calculates
An arc occurrence determination unit that determines whether or not arc discharge has occurred between the pantograph and the overhead wire based on whether or not the change amount is equal to or greater than a third threshold value;
Arc discharge determination apparatus comprising:   The arc generation determination unit determines a ratio of time in which the change amount is equal to or more than the third threshold among preset times, or the change amount of the visible light image in the number of frames set in advance. The ratio of the visible light image having a threshold of 3 or more is calculated as the frequency of occurrence of arc discharge, and it is determined that arc discharge has occurred between the pantograph and the overhead wire when the frequency of occurrence of arc discharge is 4 or more. The arc discharge determination apparatus according to claim 3.   The arc occurrence determination unit calculates a time interval in which the change amount is equal to or more than the third threshold, calculates a diversity of calculation results of the time interval, and when the diversity is large, the pantograph and the overhead wire The arc discharge determination apparatus according to claim 3, wherein it is determined that arc discharge has occurred between the two.   The arc discharge determination apparatus according to claim 3, wherein the arc occurrence determination unit calculates a variety of calculation results of the change amount, and determines that arc discharge has occurred in the pantograph when the variation is large.   The arc discharge determination unit according to claim 1, wherein the arc generation determination unit determines the first threshold value based on the luminance of the visible light image determined to have not generated arc discharge between the pantograph and the overhead wire. Judgment device.   The arc discharge determination unit according to claim 3, wherein the arc generation determination unit determines the third threshold value based on the luminance of the visible light image determined to have not generated arc discharge between the pantograph and the overhead wire. Judgment device. A plurality of the imaging units,
The arc generation determination unit determines whether the change amount of the area of the high brightness area included in the visible light image is equal to or more than the third threshold in order from the visible light image obtained by the imaging of the imaging unit. The arc discharge determination device according to claim 3, wherein it is determined whether or not arc discharge has occurred between the pantograph and the overhead wire based on a scale.   The arc discharge determination apparatus according to claim 3, further comprising: a storage unit that stores a determination result as to whether or not an arc discharge has occurred between the pantograph and the overhead wire, together with information capable of identifying the determination result.   The arc discharge determination device according to claim 3, further comprising a display unit that displays a determination result as to whether or not arc discharge has occurred between the pantograph and the overhead wire.

Images