JP2011106945A - Method and apparatus for detecting discharge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a discharge detection method and a discharge detecting apparatus for sensitively and quickly detecting a generated discharge even if an area in which ultraviolet rays are detected is wide, and identifying a region in which the discharge is generated. <P>SOLUTION: An ultraviolet sensor 3 having the sensitivity in an ultraviolet band only is provided on the side of a reflection surface of a concave mirror 2. The ultraviolet sensor 3 is switched by a sensor holding part 7 attached to the concave mirror 2 between a facing position at which a detection surface faces the concave mirror 2 and a reverse position at which the detection surface is reversed relative to the concave mirror 2. While the ultraviolet sensor 3 is switched to the facing position, a concave mirror drive part 12 drives the ultraviolet sensor 3 to cause the detection direction of the ultraviolet sensor 3 to scan the detected surface 19a of a transformer 19 as a detection object. The region as the detection object of the ultraviolet sensor 3 can be visually recognized by turning on a visible light marker 4. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a discharge detection method and a discharge detection apparatus that detect the occurrence of discharge in a detection object by detecting ultraviolet rays.

  Conventionally, in a power receiving device such as a transformer or a circuit breaker, a discharge may occur due to aged deterioration of an insulating material used or a change in installation environment such as fouling or moisture absorption. If the state in which the discharge occurs is left unattended, there is a risk of causing damage to the power receiving device or a decrease in performance, and therefore it is desired to detect the occurrence of the discharge at an early stage. For this reason, a discharge detection method for detecting the occurrence of discharge by monitoring various phenomena accompanying the occurrence of discharge, such as high-frequency current flowing in a power supply line or ground line, or electromagnetic waves, ultrasonic waves, acoustic emission, ultraviolet rays, etc. has been attempted. ing.

  Now, when the power receiving device to which a high voltage is applied is the detection target, the sensor can be installed and the discharge can be detected in a non-contact manner, although it may be inappropriate depending on the type of the detection target and the installation environment. In addition, since it is less affected by disturbance factors in the installation environment, discharge may be detected using ultraviolet rays. In that case, as an ultraviolet ray detection means for detecting ultraviolet rays, a device using a so-called ultraviolet camera in which ultraviolet ray detection elements having sensitivity in the ultraviolet region are two-dimensionally arranged, or a photoelectric tube composed of a single ultraviolet ray detection element is used. The one used is proposed (see, for example, Patent Document 1).

JP-A-2005-241624

  However, when an ultraviolet camera is used as the ultraviolet detection means, there is an advantage that the ultraviolet rays generated from the detection target can be two-dimensionally detected, but the sensitivity of ultraviolet detection decreases as the area to be detected by ultraviolet rays becomes wider. There is a problem. In general, an ultraviolet camera has sensitivity to light outside the ultraviolet region, and an expensive ultraviolet transmission filter that transmits only ultraviolet rays is required to remove light outside the ultraviolet region, that is, disturbance light. On the other hand, when a photoelectric tube or the like is used as the ultraviolet detection means, the detection sensitivity is high, and there is an advantage that the influence of disturbance light is small because it has sensitivity only in the ultraviolet region. There is a problem that it is difficult to identify.

  The present invention has been made in view of the above circumstances, and its purpose is to detect the generation of ultraviolet rays with high sensitivity and speed even when the region to be detected with ultraviolet rays is wide, and to detect ultraviolet rays. An object of the present invention is to provide a discharge detection method and a discharge detection apparatus that can specify a generation site.

  A discharge detection device according to the present invention is a discharge detection device that detects the occurrence of discharge in a detection object by detecting ultraviolet rays generated by a discharge, and has a wide detection area in a detection direction. And a second ultraviolet ray detection means having a detection region narrower in the detection direction than the first ultraviolet ray detection means, and the second ultraviolet ray detection means are driven so as to be able to scan the detection surface of the detection object. And a driving means.

  In addition, the discharge detection method of the present invention includes a first ultraviolet detection step of detecting ultraviolet rays emitted from a detection target by first ultraviolet detection means having a wide detection region with respect to the detection direction, and the first ultraviolet detection. After the ultraviolet ray is detected by the first ultraviolet ray detection means in the process, the surface to be detected of the detection object is scanned by the second ultraviolet ray detection means having a detection region narrower than the first ultraviolet ray detection means in the detection direction. And performing a second ultraviolet ray detection step of detecting ultraviolet rays emitted from the detection object.

  According to the discharge detection device of the present invention, it is detected whether or not ultraviolet rays are generated by the first ultraviolet ray detection means having a wide detection area, and when ultraviolet rays are detected, the second ultraviolet ray detection having a narrow detection area is detected. Since the means detects the ultraviolet rays while scanning the entire detection target surface of the detection object, the ultraviolet ray generation site can be specified.

  Further, according to the discharge detection method of the present invention, when the ultraviolet ray is detected in the first ultraviolet ray detection step, the second ultraviolet ray detection means scans the detection surface of the detection object in the second ultraviolet ray detection step. It is possible to quickly identify the UV generation site.

The figure which shows schematically the structure of the discharge detection apparatus by one Embodiment of this invention. It is a figure which shows the structure of a concave mirror and an ultraviolet sensor, (a) is a top view, (b) is a side view, (c) is a side view in a state where the direction of the ultraviolet sensor is opposite to (b) Diagram showing sensitivity characteristics of UV sensor Diagram showing the directivity of the UV sensor It is a figure which shows the external appearance of a transformer, (a) is a top view, (b) is a front view, (c) is a side view. Flow chart showing UV detection process The figure which shows typically the detection field of the ultraviolet sensor in wide angle mode The figure which shows typically the detection field of the ultraviolet sensor in the narrow angle mode A figure showing an example of imaging data The figure which shows the format of each data memorize | stored in the detection data memory | storage part The figure which shows typically the scanning range of the ultraviolet sensor in the narrow angle mode It is a figure which shows the change of the display mode of the frequency mark which shows frequency data, (a) is the figure which changed display size, (b) is the figure which changed the display color, (c) is the figure which changed the external appearance The figure which shows typically the imaging data memorize | stored in the detection data memory | storage part FIG. 6A is a composite diagram of imaging data and frequency marks, FIG. 5A is a diagram showing an example of displaying a plurality of frequency marks, and FIG.

Hereinafter, an embodiment in which the present invention is applied to detection of discharge in a transformer, which is a power receiving device to which a high voltage is applied, will be described with reference to FIGS. 1 to 14.
As shown in FIG. 1, the discharge detection apparatus 1 includes a concave mirror 2, an ultraviolet sensor 3 (corresponding to an ultraviolet detection element, first ultraviolet detection means, and second ultraviolet detection means), and a visible light marker 4 (corresponding to visible light irradiation means). ), A camera 5 and a discharge detection processing unit 6 for controlling them.

  As shown in FIG. 2A, the concave mirror 2 has a reflecting surface 2a that reflects ultraviolet rays. The reflecting surface 2a of the concave mirror 2 forms a parabola in a cross-sectional view and is formed symmetrically with respect to the center line Lc of the optical axis. That is, the reflecting surface 2a forms a rotating paraboloid centered on the center line Lc of the optical axis, and the outer shape thereof is formed in a circular shape of about 100 mm, for example. The reflecting surface 2a of the concave mirror 2 reflects ultraviolet rays incident parallel to the center line Lc of the optical axis toward the focal point F of the concave mirror 2 in a specific region, that is, in a region inside the diameter of the concave mirror 2.

  An ultraviolet sensor 3 is disposed on the center line Lc of the optical axis of the concave mirror 2. The ultraviolet sensor 3 is configured by sealing an anode electrode and a cathode electrode with a glass tube. When ultraviolet light is irradiated to the cathode electrode with a DC voltage applied between the electrodes, a current from the anode electrode to the cathode electrode is generated by the internal photoelectric effect and the gas multiplication effect of the current due to the discharge. Thereby, the ultraviolet sensor 3 can detect ultraviolet rays. That is, the ultraviolet sensor 3 is a so-called photoelectric tube (multiplier tube) that can detect ultraviolet rays in a wide area with respect to the detection direction.

As shown in a graph G1 in FIG. 3, the ultraviolet sensor 3 has high sensitivity to the ultraviolet region (approximately 10 nm to 380 nm), particularly near ultraviolet rays having a wavelength of around 200 nm. The ultraviolet sensor 3 is not sensitive to light in other regions, unlike the sensitivity distribution of a general ultraviolet camera as shown in the graph G2 or G3. For this reason, the ultraviolet sensor 3 does not detect light included in sunlight as shown in the graph G4.
Further, the ultraviolet sensor 3 has a horizontal angle of about ± 60 ° or more as shown in FIG. 4 (a) and an elevation angle of about ± 60 ° or more as shown in FIG. 4 (b) with respect to the detection direction. It has sensitivity characteristics with sensitivity.

  As shown in FIG. 2B, the ultraviolet sensor 3 having such sensitivity characteristics has an opposite position where the light receiving surface 3a faces the reflecting surface 2a of the concave mirror 2, and FIG. Thus, the light receiving surface 3a is held so as to be switchable to a back position, which is a position facing the reflecting surface 2a of the concave mirror 2. At this time, the ultraviolet sensor 3 is arranged so that its detection axis (a line whose horizontal angle and elevation angle are both ± 0 °) and the center line Lc of the optical axis of the concave mirror 2 coincide with each other, and FIG. ), The light receiving surface 3a is held so as to be positioned at the focal point F of the concave mirror 2. As described above, the detection direction (the direction of the light receiving surface 3a) of the ultraviolet sensor 3 changes by 180 ° between the case of being in the facing position and the case of being in the backward position.

  The visible light marker 4 includes a laser transmitter (not shown) that generates visible light, for example, red laser light, and irradiates the object with the laser light from the irradiation surface 4a. The visible light marker 4 is disposed on the center line Lc of the optical axis of the concave mirror 2 so that the center line Lc coincides with the optical axis of the laser beam. Further, the visible light marker 4 is held so that the irradiation surface 4 a and the light receiving surface 3 a of the ultraviolet sensor 3 face away from each other. Therefore, when the ultraviolet sensor 3 is at the opposite position, the irradiation surface 4a of the visible light marker 4 is in a state facing the opposite side to the concave mirror 2 as shown in FIG. On the other hand, when the ultraviolet sensor 3 is in the back position, the irradiation surface 4a of the visible light marker 4 is in a state of facing the concave mirror 2 as shown in FIG.

  The ultraviolet sensor 3 and the visible light marker 4 are held by a sensor holding unit 7 as shown in FIG. 2A to 2C, the sensor holding unit 7 includes a base plate 8 on which the ultraviolet sensor 3 and the visible light marker 4 are placed, a sensor rotation motor 9 that rotates the base plate 8, and The support arm 10 supports the base plate 8. The base plate 8 has the ultraviolet sensor 3 and the visible light marker 4 in a state where the detection axis of the ultraviolet sensor 3, the optical axis of the visible light marker 4, and the center line Lc of the optical axis of the concave mirror 2 coincide as described above. It is placed. The sensor rotation motor 9 rotates the base plate 8 on which the ultraviolet sensor 3 and the visible light marker 4 are held, thereby switching the ultraviolet sensor 3 to the above-described facing position or back position. One end of the support arm 10 is attached to the concave mirror 2, and the sensor rotation motor 9 is attached to the other end.

  Since the support arm 10 is fixed to the concave mirror 2, the relative positional relationship between the concave mirror 2, the ultraviolet sensor 3, and the visible light marker 4 is fixed. Therefore, even if the direction of the concave mirror 2 (horizontal angle and elevation angle of the concave mirror 2) changes as described later, the detection axis of the ultraviolet sensor 3 and the optical axis of the laser light of the visible light marker 4 are the concave mirror 2 Is always kept in agreement with the center line Lc of the optical axis. In other words, when the ultraviolet sensor 3 is in the back position, the direction of the concave mirror 2 coincides with the detection direction of the ultraviolet sensor 3, and when the ultraviolet sensor 3 is in the opposite position, the direction of the concave mirror 2 is visible. The irradiation direction of the laser light emitted from the optical marker 4 coincides.

  As shown in FIG. 1, the ultraviolet sensor 3, the visible light marker 4, and the sensor holding unit 7 are connected to the sensor control unit 11. The sensor control unit 11 is connected to the discharge detection processing unit 6, a lighting control signal for controlling lighting / extinction of the visible light marker 4 based on a command signal from the discharge detection processing unit 6, and a sensor holding unit 7. A mode switching signal for switching the direction is output. In addition, the sensor control unit 11 performs discharge detection processing on the ultraviolet detection data corresponding to the ultraviolet detection signal output from the ultraviolet sensor 3 and the operation mode data indicating whether the ultraviolet sensor 3 is in the opposite position or the backward position. Output to unit 6.

  On the back surface (the surface opposite to the reflecting surface 2a) of the concave mirror 2, a concave mirror driving unit 12 as a driving means is provided. As shown in FIGS. 2A to 2C, the concave mirror drive unit 12 includes a horizontal angle rotation motor 13, a horizontal angle detection encoder 14, an elevation angle rotation motor 15, an elevation angle detection encoder 16, and a concave mirror. The holding unit 17 is configured.

  The horizontal angle rotation motor 13 changes the horizontal angle of the concave mirror 2, and the elevation angle rotation motor 15 changes the elevation angle of the concave mirror 2. Moreover, the concave mirror holding part 17 is holding | maintaining so that the concave mirror 2 from which a horizontal angle and an elevation angle change can rock | fluctuate. Therefore, the concave mirror 2 changes its horizontal angle when the horizontal angle rotation motor 13 is driven, and changes its elevation angle when the elevation angle rotation motor 15 is driven. The direction and the irradiation direction of the visible light marker 4 also change. At this time, as for the direction of the concave mirror 2, the horizontal angle is detected by the horizontal angle detection encoder 14, and the elevation angle is detected by the elevation angle detection encoder 16. The horizontal angle detection encoder 14 and the elevation angle detection encoder 16 output angle signals corresponding to the horizontal angle and elevation angle of the concave mirror 2.

  The concave mirror drive unit 12 including the horizontal angle rotation motor 13, the horizontal angle detection encoder 14, the elevation angle rotation motor 15, and the elevation angle detection encoder 16 is connected to the concave mirror control unit 18, as shown in FIG. ing. The concave mirror control unit 18 is connected to the discharge detection processing unit 6 and outputs a control signal for changing the horizontal angle and the elevation angle of the concave mirror 2 based on a command signal from the discharge detection processing unit 6. The concave mirror control unit 18 also sends the horizontal angle and elevation angle of the concave mirror 2 to the discharge detection processing unit 6 using the horizontal angle and the elevation angle of the concave mirror 2 as scanning position data based on the angle signals output from the horizontal angle detection encoder 14 and the horizontal angle detection encoder 14. Output.

  The camera 5 images the detected surface 19a of the transformer 19 that is a detection target with visible light. Unlike the concave mirror 2 described above, the orientation of the camera 5 is fixed at a position where the entire detected surface 19a can be imaged. The camera 5 is connected to an image processing unit 20 (corresponding to coordinate acquisition means). The image processing unit 20 is connected to the discharge detection processing unit 6, and acquires an image input from the camera 5 as imaging data based on a command signal from the discharge detection processing unit 6. Further, the image processing unit 20 outputs the captured data to the image monitor 21. The camera 5 and the image processing unit 20 constitute an image pickup unit referred to in the present invention.

  In addition to the concave mirror control unit 18, sensor control unit 11, and image processing unit 20, the discharge detection processing unit 6 is connected to a detection data storage unit 22 and a communication control unit 23. The discharge detection processing unit 6 is configured by a microcomputer having a CPU, ROM, RAM, and the like (not shown). For example, based on a control program stored in the ROM, the concave mirror control unit 18, the sensor control unit 11, and the image The processing unit 20 and the like are controlled. The detection data storage unit 22 is configured by a large-capacity storage medium such as a hard disk drive, a non-volatile memory, or a DVD, and stores various data. The detection data storage unit 22 may be shared with the ROM or RAM of the discharge detection processing unit 6 and store a control program or the like.

  The discharge detection processing unit 6 acquires ultraviolet detection data and operation mode data acquired from the sensor control unit 11, scanning position data acquired from the concave mirror control unit 18, imaging data acquired from the image processing unit 20, and the imaging data. The date data indicating the date and time is stored in the detection data storage unit 22. In addition, the discharge detection processing unit 6 calculates frequency data indicating the detection frequency at which ultraviolet rays are detected based on each data stored in the detection data storage unit 22, and stores the frequency data in the detection data storage unit 22. Remember. In the present embodiment, the number of times ultraviolet rays are detected within a predetermined time is calculated as frequency data.

  The communication control unit 23 enables various types of information to be communicated with an external monitoring device 25 via a wired or wireless network 24. In the present embodiment, transmission / reception of each data stored in the detection data storage unit 22 is mainly controlled. The external monitoring device 25 includes a communication unit 25a, a control unit 25b, an image monitor 25c, and the like, and displays each data of the discharge detection device 1 acquired via the communication unit 25a and the network 24 on the image monitor 25c. . This makes it possible to monitor the occurrence of discharge in the transformer 19 even at a remote location. The monitoring device 25 may be a dedicated device or a general-purpose personal computer.

  Here, the transformer 19 which is a detection target of the present embodiment will be described. The transformer 19 is a three-phase AC molded transformer formed by molding a coil in which a low voltage coil and a high voltage coil are wound around an iron core, for example, with resin. As shown in FIGS. 5 (a) to 5 (c), the transformer 19 is provided with a terminal 19c corresponding to the start of winding of the high-voltage side coil on the detected surface 19a side and a rotary type at the bottom. There are as many tap switching terminals 19d as the number of phases. A lower clamp 19e made of steel or the like is provided at the lower part of the transformer 19, and is placed and fixed on the base 19f. An upper clamp 19g, which is also made of steel or the like, is provided on the upper portion of the transformer 19, and a low voltage side terminal 19h is provided on the back side of the upper clamp 19g.

Next, the operation of the discharge detection device 1 having the above-described configuration will be described based on an actual ultraviolet ray detection process.
FIG. 6 is a diagram showing a control flow of the ultraviolet ray detection process by the discharge detection device 1. This control is mainly performed by a control program executed by the discharge detection processing unit 6.
The discharge detection device 1 first performs initial setting of the horizontal angle and the elevation angle of the concave mirror 2 in the ultraviolet ray detection process (S1). In this case, based on a command from the discharge detection processing unit 6, the concave mirror control unit 18 causes the reflecting surface 2 a of the concave mirror 2 to face the transformer 19 as shown in FIG.

  Subsequently, the sensor control unit 11 sets the ultraviolet sensor 3 at the back position and turns off the visible light marker 4 (S2). Since the ultraviolet sensor 3 has a wide detection area as described above, when it is set at the back position, that is, when the detection surface 3a of the ultraviolet sensor 3 faces the transformer 19 side, FIGS. 7 (a) and 7 (b). As shown in FIG. 5, the entire width direction and height direction of the transformer 19 enter the detection region. At this time, the visible light marker 4 is turned off because the irradiation surface 4 a faces the concave mirror 2. Hereinafter, an operation mode in which the ultraviolet sensor 3 is in the back position and the ultraviolet ray is detected in a state where the detection area is wide is referred to as a wide angle mode. Further, the step of performing the ultraviolet ray detection process in the wide-angle mode corresponds to the first ultraviolet ray detection step in the present invention.

  When the initial setting of the concave mirror 2 is completed, the discharge detection device 1 determines whether ultraviolet rays are detected as shown in FIG. 6 (S3). When the ultraviolet ray is not detected (S3: NO), the process of step S3 is repeated until the ultraviolet ray is detected. When ultraviolet rays are detected (S3: YES), the detection time and the detection frequency are stored in the detection data storage unit 22 (S4). At this time, for example, the detection frequency is calculated by repeating the ultraviolet detection in the wide-angle mode until a predetermined time elapses from the time when the ultraviolet rays are first detected. When detecting ultraviolet rays, in order to prevent erroneous detection, it is preferable to consider that discharge has occurred when ultraviolet rays exceeding a predetermined reference value are detected.

  Now, in step S3, since the ultraviolet sensor 3 is operating in the wide angle mode, it is difficult to specify in which part of the transformer 19 the ultraviolet rays are generated. Therefore, in the present embodiment, when ultraviolet rays are detected in the wide-angle mode, the operation mode of the ultraviolet sensor 3 is switched to specify the portion where the ultraviolet rays are generated, that is, the portion where the discharge is generated.

  The discharge detection device 1 determines whether data (discharge history) in which ultraviolet rays have been detected in the past is stored (S5). When the discharge history is stored (S5: YES), the horizontal angle and the elevation angle of the concave mirror 2 are set to the previously set positions (S6). In this case, the discharge detection device 1 first sets the direction of the concave mirror 2 to the previously set position (set in step S16 to be described later) in order to start measurement from a site where ultraviolet rays have been detected in the past.

  When the position of the concave mirror 2 is set in step S6, or when there is no discharge history in step S5 (S5: NO), the discharge detection device 1 sets the ultraviolet sensor 3 on the concave mirror 2 side and the visible light marker 4 Is lit (S7). When the ultraviolet sensor 3 is switched to the concave mirror 2 side, that is, the facing position facing the concave mirror 2, the light receiving surface 3a is positioned at the focal point F of the concave mirror 2 as described above. Therefore, the ultraviolet rays detected by the ultraviolet sensor 3 are limited to components parallel to the center line Lc of the optical axis of the concave mirror 2, as shown in FIGS. 8 (a) and 8 (b). In other words, the detection range of the ultraviolet sensor 3 at the opposite position is in the range parallel to the center line Lc of the optical axis of the concave mirror 2 and inside the outer shape of the concave mirror 2. In the present embodiment, since the concave mirror 2 has a diameter of about 100 mm, the detection area is also an area within a circle having a diameter of about 100 mm.

  When the ultraviolet sensor 3 is in the facing position, the apparent detection area of the ultraviolet sensor 3 is narrower than when it is in the back position. That is, the ultraviolet sensor 3 held at the facing position corresponds to the second ultraviolet detecting means in the present invention. Thus, in the present embodiment, the first ultraviolet ray detection means and the second ultraviolet ray detection means are realized by one ultraviolet sensor 3. Hereinafter, an operation mode in which ultraviolet rays in a narrow range are detected in a state where the ultraviolet sensor 3 is at the opposite position is referred to as a narrow angle mode. That is, the process of detecting the ultraviolet rays in the narrow angle mode corresponds to the second ultraviolet ray detection process in the present invention, and the concave mirror 2 and the sensor holding unit 7 for switching the detection area of the ultraviolet sensor 3 are the detection in the present invention. This corresponds to the area switching means.

  Further, in this narrow angle mode, the optical axis of the laser light L emitted from the visible light marker 4 and the optical axis of the concave mirror 2 coincide with each other. As shown in FIG. 9, it is possible to visually recognize the portion (irradiation position P) that is detected by the ultraviolet sensor 3.

  When the discharge detection device 1 shifts to the narrow-angle mode, it determines whether or not ultraviolet rays are detected (S8). If no ultraviolet ray is detected (S8: NO), it is determined whether or not a preset set time has passed (S9). If no set time has passed (S9: NO) The process of step S8 is repeated until the set time has elapsed. That is, the concave mirror 2 is in a state in which its orientation is fixed until the set time elapses at the horizontal angle and the elevation angle set in step S6 (or the initial settings). The set time is preset as a reference for calculating the detection frequency.

  On the other hand, when the ultraviolet ray is detected (S8: YES), the discharge detection device 1 images the transformer 19 with the camera 5, and the visible light marker 4 on the imaging data is irradiated. The coordinates are detected and stored, for example, in a temporary storage area or the detection data storage unit 22 (S10). As shown in FIG. 9, the irradiation position P irradiated with the visible light laser is recorded in the imaging data captured with the visible light. The discharge detection device 1, more precisely, the image processing unit 20 calculates the coordinates (X-direction and Y-direction coordinates) of the irradiation position P on the imaging data. In this case, for example, the imaging data may be binarized and calculated using a well-known image processing technique such as setting the position having the luminance equal to or higher than the threshold value to the coordinates of the irradiation position P. As described above, the visible light marker 4 irradiates the laser beam L so that the operator can visually recognize the detection part of the transformer 19 and can record the detection part as data.

  Moreover, the discharge detection apparatus 1 memorize | stores the time and detection frequency at which the ultraviolet-ray was detected (S11). As described above, since the same position is continuously detected until the set time elapses, the number of discharges generated within the set time is stored as the detection frequency. The discharge detection device 1 also stores scanning position data indicating the horizontal angle and elevation angle of the concave mirror 2 (S12). As a result, as shown in FIG. 10, the detection data storage unit 22 includes date and time data indicating the recording number (No), date (YY / MM / DD), and time (HH: MM: SS), and detection frequency. Frequency data indicating (NNN), operation mode data indicating the operation mode (M), scanning position data indicating the horizontal angle (HHHH) and elevation angle (VVVV) of the concave mirror 2, and coordinates (XXXX, YYYY) of the irradiation position P are They are stored in a state associated with each other. Note that the imaging data is separately stored in the detection data storage unit 22 in a state associated with the recording number.

  The discharge detection device 1 repeats the above steps S8, S10 to S12, and S9 until the set time elapses. When the set time has elapsed (S9: YES), it is determined whether or not scanning of all set angles has been completed (S13). For example, even if the ultraviolet ray is detected at a certain part in step S8, it is conceivable that the ultraviolet ray is also detected at another part. Therefore, if the discharge detection device 1 determines that the scanning of all the set angles has not been completed (S13: NO), the horizontal angle and the elevation angle of the concave mirror 2 are set to new values (S14), and from step S8. Repeat the process.

  Thus, as shown in FIGS. 11A and 11B, the discharge detection device 1 is preset on the detected surface 19 a of the transformer 19 while changing the horizontal angle and the elevation angle of the concave mirror 2. Scan all set angles. At this time, the set angles of the horizontal angle and the elevation angle may be set based on, for example, scanning position data in which ultraviolet rays have been detected in the past, or sequentially at regular intervals in the width direction or the height direction of the transformer 19. You may make it set. However, in the case of the transformer 19, the terminals 19c and 19h, the tap switching terminal 19d, and the like described above are portions where discharge is relatively likely to occur, so that the horizontal position based on the scanning position data of the portion where ultraviolet rays have been detected in the past. When the angle and the elevation angle are set as the set angles, it is possible to improve the efficiency of ultraviolet detection.

  Now, if the discharge detection apparatus 1 determines that scanning of all set angles has been completed (S13: YES), it calculates an ultraviolet detection range (S15). When the generation of a large number of ultraviolet rays is detected in the narrow angle mode, the display of the frequency mark M described later may be complicated. For this reason, the discharge detection device 1 collects a single ultraviolet ray generation site within a predetermined range from the coordinates of the irradiation position P based on each data (see FIG. 10) stored in the detection data storage unit 22. In order to display the frequency mark M, an ultraviolet detection range is calculated.

  Subsequently, the discharge detection device 1 calculates and stores the horizontal angle and the elevation angle as the next detection start position (S16). The next detection start position is the horizontal angle and elevation angle set in step S6 in the next ultraviolet ray detection operation. The discharge detection device 1 sets the average value of the horizontal angle and the elevation angle stored in the detection data storage unit 22 as the next detection start position. In addition, when there are few UV detection parts and the average value of the calculated horizontal angle and elevation angle is far from the actual horizontal angle and elevation angle, the horizontal angle and elevation angle at which UV was detected most recently are detected. You may set as a starting position.

  And the discharge detection apparatus 1 displays each data on the image monitor 21 with imaging data (S17). At this time, the discharge detection apparatus 1 displays the frequency mark M indicating the detection frequency of ultraviolet rays based on the frequency data stored in the detection data storage unit 22 for each ultraviolet ray detection range calculated in step S15. For example, as shown in FIG. 12A, when the detection frequency is low, the frequency mark M1a has a relatively small outer shape, and when the detection frequency is medium, the frequency mark M1b is slightly larger than the frequency mark M1a. When the frequency is large, it is displayed as a larger frequency mark M1c. The discharge detection device 1 changes the display color (small: blue, medium: yellow, large: red, etc.) according to the detection frequency, for example, as shown in FIG. The frequency marks M2a to M2c are displayed, or the frequency marks M3a to M3c in which the display format (small: ◯, medium: Δ, large: x, etc.) is changed as shown in FIG. It may be. In short, the display mode may be changed so that the operator who monitors the image monitor can visually identify the detection frequency.

  Moreover, the discharge detection apparatus 1 can display not only individual image data, but also pseudo-synthesize them based on a plurality of image data. For example, when four pieces of imaging data are stored as shown in FIG. 13 during the ultraviolet detection operation in the narrow angle mode, the discharge detection device 1 takes four images as shown in FIG. Each piece of data associated with the data may be displayed together with the four frequency marks M4a to M4d. As a result, it is possible to easily grasp the position and number of the parts where the generation of ultraviolet rays is detected in the current ultraviolet ray detection operation. Further, as shown in FIG. 14B, the cursor lines Cx, Cy are moved by an input means (not shown) to select a desired frequency mark M, and the selected frequency mark M (cursor line in FIG. 14B) is selected. For example, date / time data, frequency data, and the like stored corresponding to the frequency mark M4b) corresponding to the intersection of Cx and Cy may be displayed.

  When the display of the imaging data is completed, the discharge detection device 1 transmits a detection result in response to a request from the external monitoring device 25 (S17). Thereby, also in the external monitoring device 25, for example, imaging data of a part where ultraviolet rays are detected as shown in FIGS. 12 to 14 or each data stored in the detection data storage unit 22 as shown in FIG. It becomes possible to confirm. Note that the monitoring device 25 is, for example, one installed in the office of the site where the transformer 19 is installed, or one installed in a remote place via the Internet or a wireless network.

When the detection result is transmitted, the discharge detection device 1 proceeds to step S1 and repeats the ultraviolet detection process.
Thus, the discharge detection device 1 operates the ultraviolet sensor 3 in the wide angle mode to detect the ultraviolet rays generated from the entire transformer 19, and the first ultraviolet detection step, that is, the ultraviolet rays are detected in the wide angle mode. When detected, the UV sensor 3 is operated in the narrow-angle mode and the second UV detection step of detecting the UV while scanning the entire transformer 19 is repeated to detect the generation of UV, and the transformer The occurrence of discharge at 19 is detected.

According to the first embodiment described above, the following effects can be obtained.
In the wide-angle mode where the detection area of the ultraviolet sensor 3 is wide, it is possible to monitor the entire detected surface 19a of the transformer 19, so that the generation of ultraviolet rays, that is, the occurrence of discharge can be detected quickly. Further, in the narrow-angle mode in which the detection area of the ultraviolet sensor 3 is narrowed, the ultraviolet ray is detected while scanning the detection surface 19a of the transformer 19, so that the ultraviolet ray generation site can be easily identified.

Since the detection region of the ultraviolet sensor 3 is switched between the wide-angle mode and the narrow-angle mode, the discharge detection device 1 can be configured with a single ultraviolet sensor 3. Further, since the ultraviolet sensor 3 having sensitivity only in the ultraviolet region is used, unlike the configuration using the ultraviolet camera, the configuration is simple and the influence of disturbance light such as sunlight is not required without providing an expensive ultraviolet transmission filter. Not receive. Therefore, a significant increase in cost can be suppressed.
Since the detection area of the ultraviolet sensor 3 is switched by the concave mirror 2 and the sensor holding unit 7 that holds the ultraviolet sensor 3 at the opposite position or the back position, the configuration of the discharge detection device 1 can be simplified.

  The concave mirror 2, the ultraviolet sensor 3, and the visible light marker 4 drive the concave mirror in a state where the center line Lc of the optical axis of the concave mirror 2, the detection axis of the ultraviolet sensor 3, and the optical axis of the laser light L of the visible light marker 4 are coincident. Since it is driven by the unit 12, it is possible to accurately specify the discharge generation site. Moreover, since the concave mirror 2, the ultraviolet sensor 3, and the visible light marker 4 are driven integrally, calibration such as alignment is not required at the time of detection, and the working efficiency of the detection operation can be improved.

  When detecting ultraviolet rays in the narrow-angle mode, the laser beam L indicating the detection direction of the ultraviolet sensor 3 is emitted from the visible light marker 4, so that the irradiation position P that is a detection target can be easily confirmed. In addition, since it is possible to calculate the coordinates of the irradiation position P from the imaging data in the image processing unit 20, it is possible to extract the part where the ultraviolet rays are generated as data, and to confirm the history of the part where the ultraviolet rays are generated. The efficiency of maintenance of the transformer 19 can be improved.

When ultraviolet rays are detected during operation in the narrow-angle mode, the camera 5 for imaging the detected surface 19a of the transformer 19 with visible light is provided, so that imaging data can be stored together with the laser light L indicating the detection position. In addition, since the image monitor 21 for displaying the captured image data is provided, it is possible to easily identify the discharge occurrence site.
Since there is provided a detection data storage unit 22 for storing operation mode data, coordinate data, scanning position data, imaging data, date and time data, frequency data, and frequency data when ultraviolet rays are detected, without constantly monitoring, It is possible to easily check the history of discharge, and it is possible to recognize whether a discharge has occurred and in which part. Further, since the communication control unit 23 is provided, the transformer 19 can be monitored by the external monitoring device 25.

Since the display mode of the frequency mark M is changed based on each data stored in the detection data storage unit 22, the degree of occurrence of discharge can be easily grasped. At this time, since the ultraviolet ray generation site within a predetermined range from the coordinates of the irradiation position P is displayed together with the single frequency mark M, not the coordinates where the ultraviolet rays are detected, the display may be complicated. Absent.
Since the discharge detection device 1 can be installed in the transformer 19 in a non-contact manner, and the detection of ultraviolet rays can also be performed in a non-contact manner, it is possible to safely monitor the operating transformer 19 to which a high voltage is applied. it can.

(Other embodiments)
The present invention is not limited to the above-described embodiments, and can be applied to various embodiments without departing from the gist thereof. For example, the present invention can be modified or expanded as follows.

Although one embodiment targeting the three-phase AC mold transformer 19 as an object to be detected has been illustrated, the object to be detected is not limited to the mold transformer 19 and may be a transformer having a different number of phases or different types. Further, the present invention may be applied to all power receiving devices such as a circuit breaker.
A configuration using an ultraviolet sensor with low directivity and an ultraviolet sensor with high directivity may be employed. As a result, even during the second ultraviolet ray detection process in which ultraviolet rays are detected by a highly directional ultraviolet sensor, whether ultraviolet rays are generated from the detection target by the ultraviolet sensor having a low directivity, in other words, a wide detection area. Whether or not can be determined continuously.

Although the concave mirror 2 having the reflecting surface 2a that forms a paraboloid of revolution is used, the present invention is not limited to this, and a reflecting mirror that reflects ultraviolet rays may be used on the light receiving surface 3a of the ultraviolet sensor 3. Further, it is not always necessary to collect the ultraviolet rays on the light receiving surface 3a of the ultraviolet sensor 3, and it is sufficient if the size of the detection region of the ultraviolet sensor 3 can be changed. Furthermore, a concave mirror having a spherical surface instead of a paraboloid may be used.
As the frequency data, not only the number of UV detection times within a predetermined time but also the cumulative number of UV detection times and the number of detection times within a predetermined range may be used as the frequency data.
The scanning position of the concave mirror 2 in the narrow-angle mode may be set based on the history stored in the detection data storage unit 22, or the operator may designate a part to be detected and scan that part. May be.

The imaging data is displayed on the image monitor 21 when scanning of all the set angles is completed, but the imaging data may be displayed each time when ultraviolet rays are detected.
When ultraviolet rays are detected during operation in the narrow angle mode, imaging data including the laser light L and imaging data not including the laser light L are stored, and when the frequency mark M is displayed, imaging without the laser light L is stored. Data may be used. Thereby, the visibility of imaging data and frequency data is improved. Further, even when operating in the narrow-angle mode, the visible light marker 4 may be turned off when the ultraviolet ray is not detected, and may be turned on until imaging is completed when the ultraviolet ray is detected.

  The display mode of the frequency mark M is not limited to that exemplified in the embodiment, and the frequency mark M may be blinked, for example. For example, when a plurality of frequency marks M indicating a part where ultraviolet rays have been detected recently are superimposed on a moving image (see FIG. 14), if a part where ultraviolet rays have been detected most recently blinks, ultraviolet rays are easily generated. The site and time of occurrence can be recognized. In short, the display mode of the frequency mark M may be changed so that the operator can easily recognize the detection of ultraviolet rays, that is, the occurrence and frequency of discharge.

The imaging data may be a still image or a moving image. In that case, a moving image (real-time video) is always displayed on the display monitor, and when ultraviolet rays are detected, a frequency mark M (each data such as date / time data as necessary) is displayed. Can be simultaneously monitored, and it is possible to quickly respond to the occurrence of discharge.
In one embodiment, the concave mirror 2 has a diameter of about 100 mm, but is not limited thereto. For example, it may be set according to the size of the terminal 19c or the tap switching terminal 19d, or the detected surface 19a or 19b of the transformer 19 as a detection target is divided into a plurality of monitoring areas, and the detection areas are each You may set to the magnitude | size which can cover a monitoring area | region. Alternatively, the size of the detection area may be switched by changing the size of the concave mirror 2.

  Although the ultraviolet ray detection range is calculated and the ultraviolet ray generation portions existing within the predetermined range are collectively displayed with one frequency mark M, they may be individually displayed. Further, some of the times when the ultraviolet rays are detected may be displayed. Or you may enable it to set whether to display according to the frequency with which the ultraviolet-ray was detected, such as displaying a thing with much frequency.

  In one embodiment, the discharge detection device 1 is provided on the detected surface 19a side of the transformer 19, but the discharge detection device 1 may also be provided on the detected surface 19b side. At this time, you may make it share the sensor control part 11, the concave mirror control part 18, and the image process part 20 of one discharge detection apparatus 1 with the to-be-detected surface 19a side and the to-be-detected surface 19b side. Further, a plurality of ultraviolet sensors 3 may be arranged on one detected surface side so that a site where discharge has occurred can be identified more quickly, and a plurality of transformers 19 can be provided with one discharge detection device 1. You may make it monitor.

The detection area may be switched by changing the direction, size, or the like of a reflecting mirror that reflects ultraviolet rays. For example, the detection surface 19a is detected by changing the diameter of the concave mirror 2, expanding the detection area of the highly directional ultraviolet sensor 3 using a convex mirror or a lens, or fixing the position of the ultraviolet sensor 3 and swinging the reflecting mirror. It is good also as a structure of scanning. Further, the size of the detection region of the ultraviolet sensor may be optically changed by combining a plurality of reflecting mirrors.
It is good also as a structure which provides the alerting | reporting means which alert | reports generation | occurrence | production of an ultraviolet-ray to an operator with an audio | voice etc. As a result, the need to constantly monitor the image monitor 21 is reduced, and the burden on the operator can be reduced.

  In the drawings, 1 is a discharge detection device, 2 is a concave mirror, 3 is an ultraviolet sensor (first ultraviolet detection means, second ultraviolet detection means, ultraviolet detection element), 4 is a visible light marker (visible light irradiation means), and 5 is a camera. (Imaging means), 7 is a sensor holding section (holding means, detection area switching means), 12 is a concave mirror driving section (driving means), 19 is a transformer (detection target), and 20 is an image processing section (coordinate acquisition means). 21 and 25c are image monitors (display means), 22 is a detection data storage section (storage means), 23 is a communication control section (communication means), 25 is a monitoring device, P is a site (visible light irradiation position), M, M1a, M1b, M1c, M2a, M2b, M2c, M3a, M3b, M3c, M4a, M4b, M4c, and M4d are frequency marks, L is laser light (visible light), and Lc is the center line of the optical axis.

Claims (13)

A discharge detection device that detects the occurrence of discharge in an object to be detected by detecting ultraviolet rays generated by discharge,
First ultraviolet detection means having a wide detection area with respect to the detection direction;
A second ultraviolet ray detection means having a detection region narrower in the detection direction than the first ultraviolet ray detection means;
Driving means for driving the second ultraviolet ray detection means so as to be able to scan the surface to be detected of the detection object;
A discharge detection device comprising: One ultraviolet ray detection element that also serves as the first ultraviolet ray detection unit and the second ultraviolet ray detection unit;
Detection region switching means for switching the detection region of the ultraviolet detection element;
The discharge detection device according to claim 1, further comprising: A concave mirror that reflects ultraviolet light,
The detection position of the ultraviolet detection element attached to the concave mirror and the detection position of the ultraviolet detection element on the center line of the optical axis of the concave mirror is a position where the detection direction faces the concave mirror and the ultraviolet light reflected by the concave mirror can be detected. Holding means for holding the switchable to a back-facing position, which is a position where the direction of the ultraviolet light incident on the concave mirror can be detected.
The detection region switching means switches the detection region by switching the ultraviolet detection element to the facing position or the back position by the holding means, and when the ultraviolet detection element is in the back position, 1 function as an ultraviolet ray detection means, and when the ultraviolet ray detection element is in the facing position, function as the second ultraviolet ray detection means,
The driving means drives the ultraviolet detecting element functioning as the second ultraviolet detecting means so as to be able to scan the surface to be detected of the detection object by changing the horizontal angle and the elevation angle of the concave mirror. The discharge detection device according to claim 2. Visible light irradiation means for irradiating the detection target with visible light indicating the detection direction of the ultraviolet ray detection element functioning as the second ultraviolet ray detection means,
The said visible light irradiation means is hold | maintained at the said holding means with the said 1st ultraviolet-ray detection means in the state which the irradiation direction of visible light and the detection direction of the said ultraviolet-ray detection element faced back. The discharge detection apparatus as described. Imaging means for imaging the detection surface of the detection object with visible light;
Coordinate acquisition means for acquiring coordinate data of a visible light irradiation position, which is a position irradiated with visible light, from imaging data imaged by the imaging means in a state in which visible light is irradiated by the visible light irradiation means;
The discharge detection device according to claim 4, further comprising:   Operation mode data indicating whether the first ultraviolet ray detection means is at the opposite position or the backward position, coordinate data obtained by the coordinate obtaining means, and the first ultraviolet ray detection held at the opposite position Scanning position data indicating the horizontal angle and elevation angle of the concave mirror at the time when ultraviolet rays are detected by the means, imaging data imaged by the imaging means, date / time data indicating the date and time when the imaging data was imaged, and ultraviolet rays are detected 6. The discharge detection apparatus according to claim 5, further comprising storage means for storing frequency data indicating the detected frequency.   At least one of the operation mode data, the coordinate data, the scanning position data, the imaging data, the date / time data, the frequency data, and a frequency mark selected according to the frequency data can be displayed. The discharge detection apparatus according to claim 6, further comprising a display unit. A first ultraviolet ray detection step of detecting ultraviolet rays emitted from the detection object by the first ultraviolet ray detection means having a wide detection area with respect to the detection direction;
After the ultraviolet ray is detected by the first ultraviolet ray detection unit in the first ultraviolet ray detection step, the second ultraviolet ray detection unit having a detection area narrower than the first ultraviolet ray detection unit in the detection direction is used to detect the detection object. A second ultraviolet ray detection step of detecting ultraviolet rays emitted from the detection target while scanning the detection surface;
The discharge detection method characterized by implementing. The discharge detection method according to claim 8,
In the second ultraviolet detection step, the discharge detection method irradiates the detection target with visible light in order to specify a scanning position which is a position scanned by the second ultraviolet detection means. The discharge detection method according to claim 9,
An imaging step of imaging the detection surface of the detection object in a state where the visible light is irradiated;
A coordinate acquisition step of acquiring coordinate data indicating a visible light irradiation position, which is a position where the visible light is irradiated, from the imaging data captured in the imaging step;
The discharge detection method characterized by performing. The discharge detection method according to claim 10, wherein
Calculation based on scanning position data indicating a scanning position at the time when ultraviolet rays are detected in the second ultraviolet ray detection step, the imaging data, date / time data indicating the date / time when the imaging data was taken, the coordinate data, and the date / time data. A discharge detecting method, comprising: storing a frequency data indicating a detection frequency at which detected ultraviolet rays are detected. The discharge detection method according to claim 11,
A scan start position, which is a position at which scanning of the detection object is started in the second ultraviolet ray detection step, is set to the scan position data stored most recently among the scan position data stored in the storage step. Discharge detection method. The discharge detection method according to claim 12,
A discharge detection method comprising: setting a scan start position, which is a position at which scanning of the detection object is started in the second ultraviolet ray detection step, to an average value of scan position data stored in the storage step.

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