JP7226202B2 - Partial discharge monitor - Google Patents

Description

TECHNICAL FIELD The present invention relates to a partial discharge monitoring device, and more particularly to a sensor mounting method for detecting partial discharge inside a tank having a side-by-side configuration.

Conventionally, a sensor is attached to the surface of a tank such as a transformer, and the partial discharge current (high-frequency current) generated inside the tank is measured by the sensor as potential fluctuation (surface voltage) on the surface of the tank.

JP 2017-58276 A JP-A-2005-43063

FIG. 5 shows a schematic diagram of a partial discharge monitoring device in a conventional H-AIS (hybrid (dry) air insulated switchgear). FIG. 5 shows a case of six boards as an example. In the case of H-AIS, the tanks of the 1st board 1 to the 6th board 6 are arranged side by side and have the same number of tanks as the number of the parallel boards. For this reason, conventionally, the sensors 9a to 9f are attached to the tank surfaces of all the first plate 1 to the sixth plate 6, which increases the cost.

As described above, it is a problem to reduce the number of sensors for detecting partial discharge and reduce the cost of the partial discharge monitoring device.

The present invention has been devised in view of the conventional problems described above, and one aspect of the present invention is partial discharge detection in which a sensor detects the partial discharge current generated inside each tank of a plurality of boards as potential fluctuations on the surface of the tank. The apparatus is characterized in that the sensor is provided in the vicinity of a grounding busbar attached to the surface of the tank.

Further, as one aspect thereof, a sensor mounting bracket for mounting the sensor to the grounding busbar is provided, and the sensor mounting bracket includes a base portion fixed to the tank and an end portion of the base portion which is bent and extended. and a sensor fixing portion, which is bent and extends from an end portion of the extension portion in the opposite direction to the base portion, to which the sensor is fixed.

In one aspect, the pitch of the screw holes in the base is the same as the pitch of the terminal holes in the ground bus.

Further, as one aspect thereof, the sensor fixing portion has a mounting hole for fixing the sensor, and the mounting hole is located near two diagonal corners out of the four corners of the sensor fixing portion. characterized by being formed in

Advantageous Effects of Invention According to the present invention, it is possible to reduce the number of sensors for detecting partial discharge in a partial discharge monitoring device, thereby reducing costs.

1 is a schematic diagram showing a partial discharge monitoring device according to Embodiment 1; FIG. FIG. 8 is a diagram showing a sensor mounting bracket according to the second embodiment; FIG. 8 is a schematic diagram showing an example of attachment of the sensor mounting bracket according to the second embodiment; FIG. 8 is a diagram showing the relationship between the sensor mounting bracket and the sensor according to the second embodiment; Schematic diagram showing a conventional partial discharge monitoring device.

Embodiments 1 and 2 of the partial discharge monitoring device according to the present invention will be described in detail below with reference to FIGS. 1 to 4. FIG.

[Embodiment 1]
FIG. 1 shows a schematic diagram of a partial discharge monitoring device according to the first embodiment. In FIG. 1, as an example, a panel structure having six tanks, ie, a first panel 1, a second panel 2, a third panel 3, a fourth panel 4, a fifth panel 5, and a sixth panel 6 is used.

In FIG. 1, reference numeral 7 denotes ground busbars attached to the tank surfaces of the first plate 1 to sixth plate 6, reference numeral 8 denotes ground busbar connection points, and 9a and 9b denote sensors. The arrows in FIG. 1 indicate the tank surface current. The sensors 9a and 9b measure partial discharge currents (high-frequency currents) generated inside the tanks of the first plate 1 to the sixth plate 6 as potential fluctuations (surface voltage) on the surface of the tank.

From the partial discharge generated in the main circuit insulator inside each tank of the first board 1 to the sixth board 6, part of the discharge current is diverted to the ground by the base part, but part is attached to the tank surface Electricity is energized toward the ground bus 7 . This current finally reaches the ground wire connection points 8 of the entire row board.

The sensors 9a and 9b of the first embodiment are provided near the ground bus 7 because they cannot receive strong signals if they are far from the ground bus 7. FIG. Further, in the partial discharge monitoring device of the first embodiment, as shown in FIG. A sensor 9a is provided. Further, among the three panels of the fourth panel 4, the fifth panel 5, and the sixth panel 6, the sensor 9b is provided in the tank of the fifth panel 5 in the center.

As described above, by attaching the sensors 9a and 9b in the vicinity of the grounding bus line 7 of the center board among the three boards, the three boards including the center board and the boards on both sides thereof are used as one housing. It becomes possible to collectively measure the voltage. In the first embodiment, since the sensors 9a and 9b are provided on the second board 2 and the fifth board 5, as shown by the circles in FIG. By measuring the voltage, the sensor 9b can measure the surface voltage of the fourth board 4 to the sixth board 6. FIG. As described above, in Embodiment 1, since the panel configuration is such that there are six panels in a row, the surface voltage of the ground bus 7 can be detected by the two sensors 9a and 9b.

As described above, conventionally, it was necessary to provide a sensor for each panel. It is sufficient to provide one sensor in the . As a result, it is possible to reduce the number of sensors for detecting partial discharge and reduce costs.

[Embodiment 2]
When measuring voltage fluctuations on the surface of a tank, it is necessary to attach a sensor to the surface of the tank.

In the second embodiment, the sensor mounting metal fitting 11 for extracting potential from the grounding bus 7 is shaped as shown in FIG. 2 to standardize the sensor mounting method.

2A and 2B are a side view and a plan view showing the sensor mounting bracket 11 according to the second embodiment. As shown in FIG. 2, the sensor mounting bracket 11 of the second embodiment includes a base portion 12 fixed to the tank of the board, an extension portion 13 bent and extended from the end of the base portion 12, and an extension portion 13. The sensor fixing portion 14 is bent and extended from the opposite end of the base portion 12 of the installation portion 13 and has a crank shape. The sensor 9 (9a, 9b) is fixed to the sensor fixing portion 14. As shown in FIG.

As shown in FIG. 2, the base 12 is formed with screw holes (bolt holes) 15 for fixing to the tanks of the first plate 1 to the sixth plate 6 . Here, P is the pitch of the screw holes 15 .

As shown in FIG. 2, the sensor fixing portion 14 is provided with mounting holes (screw holes or bolt holes) 16 for fixing the sensors 9 (9a, 9b). Here, although FIG. 2 shows a configuration in which four mounting holes 16 are formed, they may be formed in the vicinity of two diagonal corners among the four corners of the sensor fixing portion 14 .

FIG. 3 shows a mounting example of the sensor mounting bracket 11 and the sensor 9 in the second embodiment. The grounding busbar 7 of the H-AIS is located near the power cable connecting portion, and the power cable 17 may be pulled out upward or downward, or upward and downward. FIG. 3(a) shows the case where the power cable 17 is pulled in from above, and FIG. 3(b) shows the case where the power cable 17 is pulled in from below.

As shown in FIGS. 2 and 3, the base portion 12 is fixed to the ground busbar 7 and the sensor 9 is fixed to the sensor fixing portion 14 .

According to the sensor mounting bracket 11 of Embodiment 2, as shown in FIG. As shown, it can also be fixed to the sensor mounting bracket 11 so as to cover the ground busbar 7 downward. Although not shown, the sensor mounting bracket 11 can be fixed so as to cover the ground busbar 7 in the left direction, or the sensor mounting bracket can be fixed so as to cover the ground busbar 7 in the right direction.

By forming the sensor mounting bracket 11 into a crank shape in this manner, even when the power cable 17 is pulled in from either direction, the single type of sensor mounting bracket 11 prevents interference with the wire bundle 7a of the grounding bus 7. can do.

Moreover, by setting the pitch P of the screw holes 15 of the sensor mounting bracket 11 to the same dimension as the pitch of the terminal holes of the grounding bus 7, it is possible to mount the sensor in the vertical direction at any position on the grounding bus 7, thereby increasing versatility. Become.

FIG. 4 shows the relationship between the sensor mounting bracket 11 and the sensor 9. As shown in FIG. In FIG. 4 , mounting holes 16 are formed in the vicinity of two diagonal corners of the four corners of the sensor fixing portion 14 . As a result, the sensor 9 can be rotated by 180° and attached to the sensor mounting bracket 11 . As a result, the connector of the output cable of the sensor 9 can be oriented either left or right.

In FIG. 4, the sensors 9 are arranged above and below the grounding busbar 7 for the sake of explanation, but the sensor 9 is placed below the grounding busbar 7 when it is drawn in from above as shown in FIG. 3(a). , as shown in FIG.

As described above, according to the second embodiment, the sensor mounting bracket 11 can be assembled into one type of shape and standardized.

Moreover, the sensor mounting bracket 11 can be mounted in either the vertical direction or the horizontal direction, and interference with the grounding bus 7 can be suppressed regardless of the direction in which the power cable 17 is drawn.

Further, by setting the pitch of the screw holes 15 of the sensor mounting bracket 11 to the same dimension as the pitch of the terminal holes of the ground bus 7, the sensor 9 can be attached to any position on the ground bus 7. FIG.

Further, by forming mounting holes 16 near two diagonal corners of the four corners of the sensor fixing portion 14, the sensor 9 can be mounted by rotating it 180° with respect to the sensor mounting bracket 11. can. Therefore, the output cable of the sensor 9 can be oriented either left or right.

Although the present invention has been described in detail only with respect to the specific examples described above, it is obvious to those skilled in the art that various modifications and modifications are possible within the scope of the technical idea of the present invention. Such variations and modifications are, of course, covered by the claims.

For example, in Embodiment 1, a row-by-board configuration having six boards has been described, but the number of boards may be plural.

1 to 6: 1st to 6th panel 7: Grounding busbar 8: Grounding busbar connection point 9: Sensor 11: Sensor mounting bracket 12: Base 13: Extension part 14: Sensor fixing part 15: Screw hole 16: Mounting hole 17: Power cable P: Pitch

Claims (3)

A partial discharge detection device for detecting partial discharge current generated inside each tank of a plurality of boards as a potential variation on the surface of the tank with a sensor,
The sensor is provided near a ground busbar attached to the tank surface ,
a sensor mounting bracket for attaching the sensor to the ground busbar;
The sensor mounting bracket is
a base secured to the tank;
an extension portion that is bent and extends from an end portion of the base;
a sensor fixing portion that is bent and extends from an end portion of the extension portion in the opposite direction to the base portion and to which the sensor is fixed;
A partial discharge monitoring device comprising : 2. The partial discharge monitoring device according to claim 1, wherein the pitch of the screw holes in the base is the same as the pitch of the terminal holes in the ground bus. The sensor fixing portion has a mounting hole for fixing the sensor,
3. The partial discharge monitoring device according to claim 1 , wherein the mounting holes are formed in the vicinity of two diagonal corners of the four corners of the sensor fixing portion.

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