JP5564351B2 - How to determine whether a distribution device is submerged - Google Patents

Description

  The present invention relates to a flooded presence / absence determination method for determining whether or not there is water inside a power distribution device.

  Power distribution devices such as circuit breakers and switches are installed outdoors by being fixed to a brace provided at the top of the utility pole. For this reason, the power distribution equipment is filled with rainwater that has entered the distribution equipment due to rusting of the main body case due to long-term use and airtight defects due to deterioration of the packing provided in the assembly part of the main body case. May be in an insulation deterioration state. Thus, when the inside of the power distribution device is in an insulation deterioration state, it may cause various accidents such as a short circuit failure and a ground fault. In view of this, the distribution equipment is regularly inspected for water immersion.

  As an inspection method for the presence or absence of flooding of power distribution equipment, methods such as an electrical contact method, a display device display method, and an ultrasonic method are considered. The electrical contact type is provided with an insulation resistance measuring device for measuring insulation resistance in the power distribution device, and detects that there is water immersion when the insulation level becomes a set value or less (see, for example, Patent Document 1). In addition, the indicator display type is a method of attaching a display that contains a discoloring substance that changes color when exposed to water to a distribution device, and connecting the discoloring material and the distribution device with a connecting member. The presence of water immersion is detected (for example, see Patent Document 2). In addition, the ultrasonic type detects the presence or absence of water immersion by transmitting ultrasonic waves to the bottom surface of the power distribution device and measuring the reflected waves reflected (see, for example, Patent Document 3).

JP 2000-46894 A JP-A-5-334944 JP-A-4-348274

  By the way, among the above-described methods for determining whether or not a power distribution device is flooded, the electrical contact method and the display device display method must be attached from the stage of manufacturing the power distribution device, and the structure of the power distribution device becomes complicated. In addition, in the ultrasonic type, it is necessary to contact the device with the bottom surface of the power distribution device, but since the device is operated away from the power distribution device to prevent electric shock, it is difficult to reliably contact the device with the power distribution device. There was a possibility that it could not be measured accurately. Therefore, there has been a demand for a method for determining whether or not a power distribution device has flooded, which has a simple configuration and can determine whether or not flooded without contact.

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a flooding presence / absence determination method for a power distribution device that has a simple configuration and can determine whether flooding occurs without contact.

Hereinafter, means for achieving the above-described object and its operation and effects will be described.
According to the first aspect of the present invention, the cooling device is allowed to cool until the frost adheres from the lower end of the outer surface of the case of the power distribution device to the upper side, and there is water immersion when a part of the frost disappears. It is determined that the boundary between the place where the frost has disappeared and the place where the frost has disappeared is the water level, and if the entire frost has disappeared, it is determined that there is no flooding. It is a summary.

  According to this configuration, frost is attached to the position extending from the lower end of the outer surface of the case of the power distribution device to the upper position by the cooling means, so that the frost is attached and left. The lower end includes the lower surface. And the frost adhering to the outer surface of this case begins to disappear from the place where the temperature of a case is high with progress of time. Here, when water enters the case of the power distribution equipment and there is water, the speed at which the frost disappears due to a temperature difference between the part that is in contact with the water and the part that is not in contact with the case. Is different. Therefore, the adhering frost is not uniform over time, and if some of it disappears, it is determined that there is a temperature difference in the case due to water immersion, and it is determined that there is water immersion. Is the water level. Further, when the attached frost disappears uniformly over time, it is determined that there is no water immersion. Therefore, while having a simple configuration of cooling by the cooling means, it is possible to determine the presence or absence of water immersion without contact.

  According to the present invention, the configuration is simple and the presence or absence of water immersion can be determined without contact.

The schematic block diagram which shows the water immersion presence / absence determination method of a switch. (A) The figure which shows the frost and water level which adhered to the switch, (b) The figure which shows the state which a part of frost adhering to the switch melt | dissolved. The schematic block diagram which shows the water immersion presence / absence determination method of a switch. The figure which shows the surface temperature measured by thermography. The figure which shows the surface temperature measured by thermography. The schematic block diagram which shows the water immersion presence / absence determination method of a switch. The figure which shows the cooling range and water level of a switch. The figure which shows the surface temperature measured by thermography. The schematic block diagram which shows the water immersion presence / absence determination method of a switch. The figure which shows the heating range and water level of a switch. The figure which shows the surface temperature measured by thermography.

(First embodiment)
A first embodiment of the present invention will be described below with reference to FIGS. 1 and 2.
As shown in FIG. 1, the switch 1 is installed outdoors while being fixed to a brace 3 provided on the upper part of the utility pole 2. For this reason, the switch 1 is filled with rainwater or the like due to intrusion due to rusting of the main body case 10 due to long-term use or airtight failure due to deterioration of the packing provided in the mounting portion (not shown). The inside may be in an insulation deterioration state. Therefore, the switch 1 is periodically inspected for water immersion.

  In the present embodiment, whether the switch 1 is submerged is visually determined using the cooling spray 4. That is, a nozzle 5 having an insulation distance W from the switch 1, for example, a length of 2 m, is connected to the cooling spray 4, and the coolant is sprayed from the tip of the nozzle 5 to the outer surface of the body case 10 of the switch 1. . Here, when the coolant is sprayed onto the switch 1 by the cooling spray 4, it is carried out by approaching the switch 1 while maintaining an insulation distance W from the switch 1 with an aerial work vehicle (not shown). It is desirable that the tip of the nozzle 5 approaches the outer surface of the main body case 10 to be less than 200 mm. The cooling spray 4 is for electric equipment using nonflammable gas. The cooling spray 4 corresponds to a cooling means.

  Subsequently, as shown in FIG. 2A, it is desirable to inject the coolant onto the surface of the main body case 10 of the switch 1 where the electrical connection portion is not exposed. That is, it is desirable to spray the coolant not on the side surface 12 to which the bushing 11 is connected, but on the front surface 14 provided with the operation handle 13 or the back surface 16 provided with the handle pointer 15 on the opposite side of the front surface 14. Therefore, in the present embodiment, the coolant is sprayed from the lower end of the back surface 16 of the main body case 10 upward until the frost F adheres. Here, the lower end also includes the lower surface 17. For example, when a small amount of water is present inside the main body case 10 and cannot be seen from the back surface 16 side, the determination is made by observing the lower surface 17. It is assumed that water exists in the main body case 10 up to the water level in the figure. The water level is not known from the outer surface of the main body case 10.

  As shown in FIG. 2A, when a certain time, for example, about 10 seconds elapses after the frost F has adhered, the lower side that is part of the frost F disappears. This occurs when the melting rate of the frost F differs depending on the specific heat difference between the portion in contact with water (submerged portion) and the portion not in contact (non-submerged portion) in the main body case 10. That is, since the water in the main body case 10 is not easily cooled by the cooling spray 4, the temperature of the non-immersed part of the cooled main body case 10 is lowered, and the temperature difference between the submerged part and the non-immersed part is increased. Therefore, the disappearance of the frost F in the non-flooded portion of the main body case 10 is slow, but the disappearance of the frost F in the flooded portion is accelerated.

  In the present embodiment, by utilizing this, a boundary line extending in the horizontal direction between a place where the frost F has disappeared and a place where the frost F has disappeared after a certain period of time is defined as a water level. That is, when a part of the frost F has disappeared after a certain period of time, it is determined that there is water immersion. On the other hand, when the frost F disappears almost the same over time, it is determined that there is no water immersion.

  Now, in this embodiment, a coolant is sprayed on the outer surface of the main body case 10 of the switch 1 by the cooling spray 4 to attach the frost F, and by seeing how the frost F disappears, water is submerged from the outside of the switch 1. The presence or absence of water can be determined, and when there is water immersion, the water level can also be confirmed. Then, if the actual water level is less than 75 mm, for example, it is safe, but if the water level measured taking into account measurement errors is 70 mm or more, it is determined that there is a risk of insulation deterioration. Replace or repair.

As described above, according to the embodiment described above, the following effects can be obtained.
(1) The coolant is sprayed by the cooling spray 4 onto the position extending from the lower end of the outer surface of the main body case 10 of the switch 1 to leave the frost F attached. And the frost F adhering to the outer surface of this main body case 10 begins to disappear from the place where the temperature of the main body case 10 is high with progress of time. Here, when water is present inside the main body case 10 of the switch 1, a temperature difference occurs between the flooded portion and the non-water-immersed portion in the main body case 10, and the speed at which the frost F disappears is different. Therefore, the adhering frost F is not uniform with the passage of time, and when a part thereof disappears, it is determined that there is a temperature difference in the main body case 10 due to water immersion, and it is determined that there is water immersion. The boundary line created by the presence or absence is the water level. Moreover, when the adhered frost F disappears uniformly over time, it is determined that there is no water immersion. Therefore, it is the simple structure of cooling with the cooling spray 4, and the presence or absence of water immersion can be determined non-contactingly.

  Further, no power source is required, and if the cooling spray 4 is prepared, the determination can be performed very easily. Furthermore, the presence / absence of water immersion can be determined even for an existing switch that is not equipped with a device for determining the presence / absence of water immersion.

(Second Embodiment)
Hereinafter, a second embodiment of the present invention will be described with reference to FIGS. The switch flooding presence / absence determination method of this embodiment is different from that of the first embodiment in that determination is made using thermography. Hereinafter, a description will be given focusing on differences from the first embodiment.

  As shown in FIG. 3, in this embodiment, the thermography 6 is used to determine whether the switch 1 is flooded. That is, the temperature distribution on the outer surface of the main body case 10 of the switch 1 is visualized from a position separated from the switch 1 by an insulation distance W, for example, 2 m. Here, when observing the switch 1 with the thermography 6, the insulation distance W from the switch 1 is kept close to the switch 1 by using an aerial work vehicle or the like (not shown) and the switch 1 is viewed from a horizontal position. Do. The thermography 6 corresponds to a thermal image measurement device.

  As shown in FIGS. 4 and 5, the thermography 6 is observed from the lower end of the back surface 16 to the upper side of the outer surface of the main body case 10 of the switch 1. Here, the lower end also includes the lower surface 17. For example, when a small amount of water is present inside the main body case 10 and cannot be seen from the back surface 16 side, the determination is made by observing the lower surface 17. It is assumed that water exists in the main body case 10 up to the water level in the figure. The water level is not known from the outer surface of the main body case 10.

  FIG. 4 is an image of the thermography 6 in a time zone in which the temperature of the outside air is relatively low from morning to evening. When water is present inside the main body case 10, the non-water-immersed part that is not in contact with water is cooled more than the water-immersed part that is in contact with water. For this reason, the image of the thermography 6 is displayed on the switch 1 with a high temperature at the lower part of the boundary where the position is the water level and a low temperature at the upper part of the boundary.

  FIG. 5 is an image of the thermography 6 in a time zone in which the daytime outside air temperature is relatively high. When water is present inside the main body case 10, the water-immersed part that is in contact with water is warmed more than the non-water-immersed part that is not in contact with water. For this reason, the image of the thermography 6 is displayed in the switch 1 with a high temperature at the upper part where the position that will be the water level is a boundary line and a low temperature at the lower part of the boundary line.

  Therefore, when the temperature distribution on the outer surface of the main body case 10 of the switch 1 is visualized, if there is a temperature difference, it is determined that there is water immersion, and the boundary line that becomes the temperature boundary is the water level. On the other hand, when there is no temperature difference, it is determined that there is no water immersion.

  Here, when the outside air temperature is very high, such as in summer, the outer surface of the main body case 10 of the switch 1 is warmed and the temperature is visualized by the thermography 6 even though water is present inside the main body case 10. Distribution may be uniform. Therefore, in such a case, the cooling spray 4 is used.

  As shown in FIG. 6, before observing with the thermography 6, as in the first embodiment, the insulation distance W from the switch 1, for example, 2 m away from the position on the outer surface of the main body case 10 of the switch 1. On the other hand, a coolant is injected from the tip of the nozzle 5. The cooling spray 4 cools the coolant by spraying the coolant from the tip of the nozzle 5 to the outer surface of the main body case 10 of the switch 1. In addition, the temperature of the outer surface of main body case 10 should just fall, and it is not necessary to inject a coolant until frost F adheres. That is, the temperature of the non-immersed part of the cooled main body case 10 is lowered, and the temperature difference between the flooded part and the non-immersed part is increased.

  As shown in FIG. 7, the coolant is injected from the lower end of the back surface 16 of the main body case 10 upward (hereinafter referred to as a cooling range). Here, the lower end also includes the lower surface 17. For example, when a small amount of water is present inside the main body case 10 and cannot be seen from the back surface 16 side, the determination is made by observing the lower surface 17. It is assumed that water exists in the main body case 10 up to the water level in the figure.

  As shown in FIG. 8, after cooling by the cooling spray 4, the thermography 6 is used to visualize the temperature distribution on the outer surface of the main body case 10 of the switch 1. In the switch 1, the image of the thermography 6 is displayed with a low temperature at the upper part where the position that is likely to be the water level is a boundary line and a high temperature at the lower part of the boundary line. This is because the main body case 10 of the switch 1 is cooled by being cooled by the cooling spray 4, but the portion where water exists is not easily cooled. In addition, at the lower part of the boundary line, the temperature outside the cooling range is displayed slightly higher than within the cooling range. Therefore, even when the outside air temperature is very high as in summer, it is possible to determine whether the switch 1 is flooded.

  Here, when the outside air temperature is very low as in winter, the outer surface of the main body case 10 of the switch 1 is cooled, and the temperature is visualized by the thermography 6 even though water is present inside the main body case 10. Distribution may be uniform. Therefore, in such a case, the spotlight 7 is used. The spotlight 7 corresponds to a heating means.

  As shown in FIG. 9, before observing with the thermography 6, the spotlight 7 warms the outer surface of the main body case 10 of the switch 1 by irradiating the light. That is, light is irradiated to the outer surface of the main body case 10 of the switch 1 from a position separated from the switch 1 by an insulation distance W, for example, 2 m. That is, the temperature of the non-immersed part of the heated main body case 10 is increased, and the temperature difference between the flooded part and the non-immersed part is increased.

  As shown in FIG. 10, light is irradiated from the lower end of the back surface 16 of the main body case 10 upward (hereinafter referred to as a heating range). Here, the lower end also includes the lower surface 17. For example, when a small amount of water is present inside the main body case 10 and cannot be seen from the back surface 16 side, the determination is made by observing the lower surface 17. It is assumed that water exists in the main body case 10 up to the water level in the figure.

  As shown in FIG. 11, after heating by the spotlight 7, the thermography 6 is used to visualize the temperature distribution on the outer surface of the main body case 10 of the switch 1. The image of the thermography 6 is displayed on the switch 1 with a low temperature at the lower part of the boundary where the position is likely to be the water level and a higher temperature at the upper part of the boundary. This is because the body case 10 of the switch 1 is heated by being heated by the spotlight 7, but the portion where water is present is not easily heated. In addition, at the upper part of the boundary line, the temperature within the heating range is displayed slightly higher than outside the heating range. Therefore, even when the outside air temperature is very low as in winter, it is possible to determine whether the switch 1 is flooded.

  Now, in this embodiment, by visualizing the outer surface of the main body case 10 of the switch 1 with the thermography 6 and seeing the temperature difference, it is possible to determine the presence or absence of flooding from the outside of the switch 1 and there is flooding. In some cases, the water level can also be confirmed. Moreover, when the temperature difference between the water-immersed part and the non-water-immersed part of the main body case 10 of the switch 1 is small, it is possible to determine whether there is water immersion by using the cooling spray 4 or the spotlight 7. And if the water level of immersion is 70 mm or more, for example, it will be judged that there exists a possibility of insulation deterioration, and the switch 1 is exchanged or repaired.

As described above, according to the embodiment described above, the following effects can be obtained.
(2) The surface temperature difference is visualized by the thermography 6 at a position extending upward from the lower end of the outer surface of the main body case 10 of the switch 1. Here, when water is present in the main body case 10 of the switch 1, a temperature difference occurs between the water-immersed portion and the non-water-immersed portion in the main body case 10. Therefore, when there is a temperature difference, it is determined that there is a temperature difference in the main body case 10 due to water immersion, it is determined that there is water immersion, and the boundary line of the temperature difference is set as a water level. If there is no temperature difference, it is determined that there is no water immersion. Therefore, while having a simple configuration of measuring by the thermography 6, it is possible to determine the presence or absence of water immersion without contact. In addition, it is possible to determine the presence or absence of water in an existing switch.

  (3) When the body case 10 of the switch 1 is warmed because the outside air temperature is very high and the temperature difference between the flooded part and the non-soaked part is small, the outer surface of the body case 10 is cooled by the cooling spray 4. For this reason, the temperature of the cooled non-immersed part is lowered, and the temperature difference between the flooded part and the non-immersed part is increased. Therefore, even when the main body case 10 of the switch 1 is warmed very high by the outside air temperature, it is possible to determine whether the switch 1 is submerged by the thermography 6 after being cooled by the cooling spray 4.

  (4) When the body case 10 of the switch 1 is cooled because the outside air temperature is very low and the temperature difference between the flooded part and the non-soaked part is small, the outer surface of the body case 10 is warmed by the spotlight 7. For this reason, the temperature of the heated non-immersed part becomes high, and the temperature difference between the flooded part and the non-immersed part becomes large. Therefore, even when the main body case 10 of the switch 1 is cooled very low by the outside air temperature, it is possible to determine whether the switch 1 is submerged by the thermography 6 after heating by the spotlight 7.

In addition, the said embodiment can be implemented with the following forms which changed this suitably.
In the first embodiment, the boundary between the place where the frost F disappears and the place where the frost F disappears after a lapse of 10 seconds after the frost F has adhered is the water level, but the fixed time is limited to 10 seconds. It can be arbitrarily set according to the outside temperature.

In the above embodiment, the insulation distance W is 2 m, but the insulation distance W can be arbitrarily set according to the voltage used and the type of the switch.
In the second embodiment, the cooling spray 4 is used when the outside temperature is very high, and the spotlight 7 is used when the outside temperature is very low. However, the thermography 6 is used regardless of the outside temperature. You may use the cooling spray 4 or the spotlight 7 together. In this way, since the temperature difference between the flooded part and the non-flooded part can be increased, it becomes easier to determine whether the switch 1 is flooded.

  -In the said 2nd Embodiment, although the cooling spray 4 was used as a cooling means, since the temperature of the outer surface of the main body case 10 should just fall and it is not necessary to make frost adhere, you may use a fan etc.

In the second embodiment, the spotlight 7 is used as the heating means, but a spot heater or the like may be used.
In the above embodiment, it is determined that the amount of water immersion (water level) is 70 mm or more and there is a risk of insulation deterioration, but it can be arbitrarily set according to the type of the switch. When an arrester or a control connector is installed as an accessory in the switch, it is necessary to determine that there is a risk of insulation deterioration at a water level lower than 70 mm.

  In the above embodiment, the cooling spray 4 for electric equipment using nonflammable gas is used. However, a cooling spray for emergency treatment used for cooling a human body at the time of sports trouble or the like may be used.

  -In the said embodiment, although applied about the switch 1, you may apply not only to the switch 1 but to other power distribution apparatuses, such as a circuit breaker.

DESCRIPTION OF SYMBOLS 1 ... Switch, 2 ... Telephone pole, 3 ... Arm metal, 4 ... Cooling spray, 5 ... Nozzle, 6 ... Thermography, 7 ... Spotlight, 10 ... Body case, 11 ... Bushing, 12 ... Side, 13 ... Operation handle, 14 ... Front, 15 ... Handle pointer, 16 ... Back, 17 ... Bottom, F ... Frost, W ... Insulation distance.

Claims (1)

From the lower end of the outer surface of the case of the power distribution equipment to above it, cool it down until the frost adheres by the cooling means, leave it,
When a part of the frost disappears, it is determined that there is flooding, and the boundary between the place where the frost has disappeared and the remaining place is regarded as a water level, and when the entire frost disappears, it is determined that there is no flooding. A method for determining whether a power distribution device is inundated or not .

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