JP6182427B2 - switchboard - Google Patents

Description

  The present invention relates to a switchboard that is installed outdoors in a solar power generation system, in which DC power obtained from a solar panel is converted into AC power by a power conditioner, and these devices are arranged and connected to a power system.

In recent years, the spread of solar power generation systems has been increasing against the background of increasing awareness of environmental conservation, such as international efforts to reduce CO _{2 to} prevent global warming. In this solar power generation system, the solar light energy is converted into DC power by the solar cell module, and this DC power is converted into AC power by the power conditioner and connected to the power system so that power can be sold.

  Specifically, the power conditioner includes an inverter that receives the output of the solar cell and converts it into a predetermined alternating current, and converts the output of the inverter into a system voltage by a transformer and is connected to the power system. The configuration of the inverter is composed of an inverter, a filter, a control circuit, and the like. The output voltage of the solar panel is converted into AC voltage by an inverter and output. In addition, in the “renewable energy feed-in tariff system”, in the case of a power conditioner of 10 kW or more, a transformer and a circuit breaker are required to connect to a 6,600 V power system. The spread is also expanding.

  In addition, since the photovoltaic power generation system is linked to the 6,600 V power system, it is necessary to connect to the power system with equipment in accordance with the grid connection regulations, such as a high voltage circuit breaker, a ground fault overvoltage relay, a transformer. Install power conditioners and solar panels. High-voltage circuit breakers, ground fault overvoltage relays, transformers, and power conditioners are often installed in the vicinity. However, when installed outdoors, high voltage circuit breakers, ground fault overvoltage relays, power receiving panels and power conditioners containing transformers are installed. It is divided into a control panel that houses the door and is generally installed outdoors. When the industrial power conditioner becomes 10 kW or more, the natural air cooling has insufficient cooling capacity, so forced air cooling by a cooling fan is required. When forced air cooling is performed, a gallery that prevents intrusion of rainwater and a dustproof filter that prevents intrusion of dust must be attached to the ventilation openings to prevent intrusion of rainwater and dust.

  Patent Document 1 (Japanese Patent Application Laid-Open No. 2000-13934) describes an outdoor type switchgear for preventing inability to ventilate due to snow accumulation, preventing condensation from falling into the box, and improving the appearance. A switchgear box housing the circuit breaker, busbar, cable, etc., an inner ceiling board covering the upper surface of the box, an outer ceiling board installed above the inner ceiling board, and an outer ceiling A heat insulating material mounted on the lower surface of the plate, an opening formed in the inner ceiling plate, a prevention plate provided above the opening to prevent dew condensation from the heat insulating material to the opening, and upward from the periphery of the opening And a prevention piece for preventing dew condensation from flowing into the opening, and an exhaust ventilation opening formed between the front part of the outer ceiling plate and the box and exhausting the exhaust from the opening. ing.

  In Cited Document 2 (Japanese Patent Laid-Open No. 2011-176900), the switchboard installed outdoors suppresses the internal temperature as a switchboard due to solar heat, penetration heat of sunlight, heat generated by the storage device, etc. A casing having a vent in the ceiling, and a ceiling opening / closing provided on the ceiling of the casing so as to be rotatable with respect to the casing, closing the ceiling when closed and opening the ceiling when opened A unit, a driving device that opens and closes the ceiling opening and closing unit, a temperature sensor that detects a temperature inside the housing, and a control device that controls the driving device according to a detection result of the temperature sensor. Has been.

JP 2000-13934 A JP 2011-176900 A

  Patent Document 1 discloses a configuration for preventing ventilation from being prevented by snow accumulation and preventing condensation from falling into the box in an outdoor switchgear, and discloses that snow, particularly snow powder, invades the box. It has not been.

  Moreover, although the cited reference 2 discloses a configuration in which the temperature in the switchboard is detected by a temperature sensor and the ceiling part is opened and closed as a measure against solar heat in the switchboard installed outdoors, but snow intrudes into the switchboard. Prevention is not disclosed.

  In addition, in the case of normal rainwater, the invasion can be prevented by installing a gallery, but in heavy snow areas such as Hokkaido, the snow particles are fine powder snow, and there is a high possibility of passing through a dust filter. In addition, raindrops have large particles, so even if they are blown by the wind, water drops fall down. Powder snow invades. When powder snow enters the inside, there is a possibility of threatening safety such as moisture adhering to the charged part.

  The present invention provides a distribution board for a photovoltaic power generation system having a structure for preventing snow, particularly powder snow, from entering the distribution board in addition to the rain water described above, and for preventing the temperature inside the distribution board from rising due to solar heat. The purpose is to provide.

In order to solve the above problems, for example, the configuration described in the claims is adopted. The present application includes a plurality of means for solving the above-described problems. To give an example, the power distribution panel of the photovoltaic power generation system, and the door portion of the power conditioner storage chamber of the distribution panel storing the power conditioner Folds both sides of the heat shield plate arranged on all or either of the side surface or the back surface to form a bent portion, and contacts the bent portion against the door portion, the side surface or the back surface to bring the air into the space. to form a layer, the door portion of the power conditioner housing chamber, to form a gallery to either all of the side portion or the back portion or the lower side, the lower side of the gallery, the fan with the heater, entering the gallery snow It arrange | positions so that it may blow out toward .

ADVANTAGE OF THE INVENTION According to this invention, the intrusion of the powder snow into a switchboard can be prevented, and the switchboard which can be drive | operated safely also in a heavy snowy area can be provided.
Moreover, since the heat shield is disposed on all or any of the door part, the side part, and the rear part of the switchboard, the temperature rise in the switchboard can be suppressed by solar heat, and safe driving can be performed.

The connection block diagram of the switchboard of a solar power generation system is shown. The external appearance perspective view of the switchboard of this invention is shown. The external appearance perspective view and partial enlarged view of the power conditioner storage room of the switchboard of this invention are shown. The external appearance perspective view of the state which removed the heat shield of the door of the power conditioner storage room of a switchboard is shown. 3A shows a side view of FIG. 3A. The upper side figure by the side of the door of the power conditioner storage room of a switchboard, and its partially enlarged view are shown. The perspective view of the gallery arrange | positioned at the door of the power conditioner storage chamber of a switchboard, and its partial sectional view are shown. The connection block diagram of the solar energy power generation system in the case of arrange | positioning a heater to a switchboard is shown. The fragmentary sectional view at the time of arrange | positioning a heater inside the door of the power conditioner storage chamber of a switchboard is shown. The fragmentary sectional view at the time of arrange | positioning the planar heater in the back side of the gallery of the door of the power conditioner storage room of a switchboard is shown. The connection block diagram of the photovoltaic power generation system which has the function to measure the external temperature of a switchboard and to control a gallery cover is shown. The control system block diagram which opens and closes the gallery cover arrange | positioned at the door of the power conditioner storage room of a switchboard is shown.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
Example 1
A first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a connection configuration diagram of a distribution board of a photovoltaic power generation system according to the present invention, where 10 is a distribution board installed outdoors, 11 is a power system for supplying power to power receiving equipment, and 12 is during normal operation of the power equipment. The circuit breaker protects the load-side equipment by linking the protective relay to link the protective relay, 13 is a transformer that converts the voltage value of AC power, and 14 is a photovoltaic power generation system. A power conditioner that converts DC power into AC power so that the transmitted electricity can be transmitted to the power system, 15 detects a ground fault in the power system and generates an alarm signal (OVGR: Over Voltage Ground Relay) ), 16 is a solar panel in which a plurality of solar cells are arranged and connected to form a panel.

  The DC power output from the solar panel 16 is input to a power conditioner 14 including an inverter, a filter reactor, a filter capacitor, etc., converted into a three-phase AC by the inverter, and a harmonic component is cut by the filter circuit. . The voltage is boosted by the transformer 13 and converted into a system voltage, which is output to the power system 11 via the circuit breaker 12 and sold. The output of the transformer 13 is connected to a ground fault overvoltage relay 15 that informs that a ground fault has occurred. In FIG. 1, MCCB (Molded Case Circuit Breaker) is a circuit breaker, MC (Magnetic Contact) is an electromagnetic contactor, and INV (Inverter) is an inverter.

  Next, the switchboard of the solar power generation system installed outdoors will be described. FIG. 2 shows an external perspective view of the switchboard of the present invention. In FIG. 2, 10 is a main body of the switchboard, 20 is a door of a power conditioner storage room containing a power conditioner such as an inverter, 21 is a room containing a circuit breaker, and a transformer 13 is placed behind it. Place and cool with outside air. 22 is a base of the switchboard 10, 23 is a roof, and 24 is a cooling fan disposed on the roof 23 on the upper side of the power conditioner storage chamber. Reference numeral 25 denotes a hanging tool arranged at the corner of the roof, which is used when the switchboard 10 is installed or removed and when it is lifted or hung by a crane. Reference numerals 26 and 27 denote handles arranged on the doors of the switchboard. The inverter housing for the inverter is housed in the inverter, and heat is generated when the inverter is operated. As a result, the indoor temperature rises, and the cooling fan 24 provided on the roof is driven to forcibly cool it to prevent the temperature from rising. ing.

  Next, the power conditioner storage room of the switchboard placed outdoors will be described. 3A, FIG. 3A (a) is an external perspective view of the inverter housing, and FIG. 3A (b) is an enlarged view of a part thereof. In FIG. 3A (a), when the switchboard is installed outdoors, the temperature in the power conditioner storage chamber of the switchboard rises due to the influence of direct sunlight. The heat shield plate 20 is arranged on the surface so that the door of the switchboard is doubled so that the temperature in the inverter housing is not increased by the direct sunlight. A space is provided between the door 29 and the heat shield plate 20 to form an air layer. As shown in FIG. 3B, the heat shield plate 20 is disposed on the door 29 and is formed of a single metal plate. In the case of forced cooling, air is taken in from both sides and the lower side of the heat shield plate. Further, in FIG. 3A (a), the heat shield plate 28 is arranged on the entire surface in the same manner on the side surface side of the switchboard (the heat shield plate is arranged side by side because the area is large in the drawing), and is shown. There is no heat shield on the entire rear side.

  Here, in FIG. 3A (a), a configuration is shown in which the heat shield plates are respectively arranged in the door portion, the side surface portion, and the rear surface portion of the power conditioner storage chamber of the switchboard, and are doubled. You may arrange | position in any one of a door part, a side part, and a back part. In the room for storing the circuit breaker of the switchboard and the like, the heat shield plate can be disposed on the entire surface of the door portion, the side surface portion, or the back surface portion as in the case of the power conditioner storage chamber. The base 22 is formed by combining a U-shaped frame into a rectangular shape, and the ceiling roof 23 has an increased thickness on the front side and a thickness that decreases toward the back side so as to be inclined. Such a configuration makes it easy for rainwater to flow and prevents snow accumulation.

  3A (b), the both sides of the heat shield 20 (not shown) on the door side of the switchboard, that is, the front side and the back side are bent to the door side to eliminate the gap between the heat shield 20 and the door 29. The bent portion 201 is brought into contact with the door 29 and brought into contact therewith. Further, the height of the bent portions 201 on both sides of the heat shield plate 20 on the door side, that is, the front side and the back side is set to be substantially the same as the height of the gallery 30 as shown in FIG. 3B. When the height of the bent portion is low, the powder snow cannot be sufficiently prevented from entering the gallery portion. On the other hand, when the height of the bent portion is high, ventilation by forced ventilation is insufficient, and the inverter temperature may stop due to the rise of the temperature inside the panel.

  Unlike the front side, both sides of the heat shield plate 28 on the side of the switchboard do not have a gallery, so there is no need to provide a bent portion, so only a space is provided to form an air layer, and direct sunlight from sunlight. It is difficult to transfer the heat of the heat shield plate to the wall surface. When arranging a gallery on the side of the switchboard, the height of the bent portion of the heat shield is the height of the gallery.

  Next, the gallery 30 disposed on the door 29 in the exploded perspective view of the heat shield 20 on the front side of the switchboard in FIG. 3B will be described. In FIG. 3B, a gallery 30 having three rows and vertically elongated vent holes is arranged below the door 29 on the front side of the switchboard. As shown in FIGS. 3E (a) and 3E (b), the shape of the gallery 30 is a longitudinal arc-shaped bulging portion 301 that protrudes outward and downward by pressing one metal plate or the like. Are formed in a plurality of stages, and a vent hole 302 is formed in the lower part of the bulging portion 301. Such a configuration of the gallery 30 can prevent rainwater, snowfall, and the like from entering the switchboard from above, and can also forcibly cool the power conditioner because ventilation is possible. In addition, as shown in FIG. 3E (c), the gallery 30 can prevent rainwater, snowfall, and the like from entering from the upper part even in the longitudinal flat plate shape protruding outward.

  Next, the lower side surface of the switchboard 10 will be described with reference to the drawings. FIG. 3C is a part of the lower side surface of the switchboard and shows a longitudinal sectional view of the door portion. In FIG. 3C, a hole 292 for arranging the gallery 30 is formed in the door 29 on the front side of the switchboard, and the gallery 30 is arranged on the door 29. In addition, a heat shield plate 20 is disposed above the gallery 30 so as to cover the gallery 30 and the door 29. The door 29 covers the entire surface as much as possible so as not to be exposed to direct sunlight, and the gallery 30 covers the side of the gallery in order to prevent snow powder from the side. The lower end 202 of the heat shield plate 20 is bent and brought into contact with the door 29 to form an air layer between the heat shield plate 20 and the door 29. A plurality of fixing bosses 31 are arranged on the heat shield 20 and the door 29, and are fixed so as to maintain a certain distance.

  Next, the structure seen from the upper surface of the door 29 on the front side of the switchboard will be described with reference to FIG. 3D. In FIG. 3D, FIG. 3D (a) shows the top view of the door of the power conditioner storage chamber of a switchboard, and FIG. 3D (b) shows the enlarged view to which a part of the door was expanded. 3D (a), the gallery 30 is arranged in three rows with respect to the horizontal direction of the door 29, and the flange portion of the gallery 30 is fixed to the door 29 with a screw or the like. Further, the heat shield plate 20 is fixed at a certain height by a door 29 and a fixing boss. Further, in the partially enlarged top view of FIG. 3D (b), reference numeral 32 denotes a frame, which constitutes a frame of the switchboard, and a hinge of the door 29 and the like are arranged although not shown. Both sides of the heat shield plate 20 are bent and brought into contact with the end of the door 29 to provide a space, and an air layer is formed to form a double structure so that the heat of the heat shield plate is not transmitted to the door.

  Further, the bottom end face of the heat shield plate 20 is also bent as shown in FIG. 3C to form a bent portion 202, which is brought into contact with the door 29 to form an air layer. FIG. 3D (b) As shown, a part of both sides of the bent portion 202 is cut out, the hole 31 is disposed, and the water accumulated in the space between the heat shield 20 and the door 29 is discharged.

  By providing the heat shield plate 20 of the present embodiment, it becomes possible to prevent intrusion of snow powder even in the forced ventilation structure while preventing direct sunlight to the door 29, and between the heat shield plate 20 and the door 29. It also becomes possible to discharge water accumulated in the space.

(Example 2)
Next, the structure of the switchboard using the heater according to the second embodiment of the present invention will be described with reference to the drawings. 4A shows a connection configuration diagram of the switchboard when a heater is used in the photovoltaic power generation system. In FIG. 4A, 40 is a heater, 41 (dotted line) is a power source of the heater 40, that is, an output of the solar panel 16, that is, Reference numeral 42 (solid line) denotes a power supply line that uses DC power, and a power supply line that uses the output of the power conditioner 14, that is, AC power, for the heater 40. The power of the heater used in the switchboard is configured to be covered by the power obtained by the solar power generation system, and can be used with either DC power or AC power.

  Next, a specific configuration using a heater in the switchboard will be described with reference to FIG. 4B. In FIG. 4B, FIG. 4B (a) shows a partial side view when a heater with a fan is arranged under the gallery inside the switchboard door, and FIG. 4B (b) is under the gallery inside the switchboard door. The partial side view at the time of arrange | positioning the heater with a cover to the side is shown. In FIG. 4B (a), the fan-equipped heater is composed of a fan 41 and a heater 42, and is arranged on the inside of the door 29 below the gallery 30 arranged on the door 29. It blows out and melts to prevent entry into the switchboard. Moreover, the temperature at which powder snow is melted does not have to be high, and warm air of about 40 to 50 ° C. is sufficient.

  In this way, even if snow enters the switchboard, it is melted by the heater and drops in the vicinity of the heater as water droplets, so that the internal equipment does not get wet, and moisture is absorbed by the attached fan 41 and heater 42. The contained air is forcibly ventilated and dried to evaporate the moisture, which allows safe operation.

  Next, in FIG. 4B (b), a heater 43 with a cover covering the heater is disposed on the inside of the door 29 of the switchboard, below the gallery 30, and snow that enters from the gallery 30, particularly powder snow, is melted into the switchboard. Prevent intrusion. The heater with cover 43 is generally a space heater provided with a heat radiating cover made of a punched steel plate. Moreover, the heater 43 with a cover is arrange | positioned by the same length as the length of the width direction of the gallery 30 of the front door of a switchboard. Thus, by attaching a heater to the lower side of the gallery, a switchboard that prevents snow from entering the switchboard can be provided.

Next, the structure which arrange | positioned the surface heater behind the gallery arrange | positioned at the door of a switchboard is demonstrated using FIG. 4C. FIG. 4C shows a view in which a surface heater 44 is arranged on the back surface of the gallery 30. The surface heater 44 includes a stainless steel foil as a heating element sandwiched between insulators such as polyimide and mica , a flexible and strong silicon rubber heater, a light and easy to install aluminum foil heater, and planar carbon. A carbon heater or the like used as a heating element is used.

  By providing the heater of this embodiment, it is possible to prevent snow from entering the switchboard, and it is possible to suppress serious accidents due to insulation breakdown of internal devices.

(Example 3)
Next, Embodiment 3 of the present invention will be described with reference to the drawings.
In the third embodiment, a lid that covers a gallery arranged on the door is attached to the inside of the front door of the switchboard, and the lid is opened and closed by the outside air temperature to prevent intrusion of snow, particularly powder snow. FIG. 5A shows a connection configuration diagram of a photovoltaic power generation system having a control function of measuring the outside temperature of the switchboard and opening and closing the lid of the door gallery. In FIG. 5A, 51 is a thermostat, measures the outside temperature of the switchboard 10, and transmits the measured temperature data to the control unit 53 in the power conditioner 14. Judgment is made based on the temperature data, and opening / closing control of the gallery lid is performed. As a result, when the outside air temperature rises, the gallery lid is opened to suppress the rise in the temperature inside the panel to increase the ventilation. When the outside air temperature falls, the gallery Close the lid to prevent snow from entering. Moreover, the control part 53 controls opening and closing of the cover which covers the gallery arrange | positioned at the door. Since the control unit 53 is driven by DC power, it is connected to the preceding stage of INV (inverter).

  Next, FIG. 5B shows a control system block diagram for opening and closing the gallery lid of the third embodiment. In FIG. 5B, a box-shaped gallery lid 50 is disposed that covers the back side of the gallery 30 disposed below the door on the front side (right side of FIG. 5B) of the switchboard. The gallery lid 50 is rotationally driven clockwise and counterclockwise by a rotating shaft 55 formed at the lower end portion, and can be opened and closed.

  In FIG. 5B, the dotted gallery lid 50 is shown in the open state, and the solid gallery lid 50 is shown in the closed state. The open / close control system for the gallery lid 50 according to the third embodiment first measures the outside air temperature of the switchboard 10 with the thermostat 51. The temperature measurement 52 measures the outside air temperature of the switchboard 10 with a thermostat 51 and transmits temperature data to the control unit 53.

  When the temperature of the outside air temperature is high, the control unit 53 opens the gallery cover 50 and performs forced air cooling to prevent the temperature inside the switchboard from rising. When the outside air temperature is high, the possibility of falling snow is small, and even if air is taken in from the gallery 30, rainwater does not enter and it is possible to drive safely.

  Moreover, since the possibility of snowfall is assumed when the outside air temperature is low, there is a possibility that snow, especially powder snow, may enter from the gallery 30 due to snowfall. In such a case, since the outside air temperature is low, it is not necessary to perform forced air cooling through the vent hole of the gallery 50, and the temperature inside the switchboard does not rise. Therefore, the intrusion of snow, especially powder snow, can be prevented by stopping the forced air cooling operation and fastening the gallery 30 with the gallery lid 50. The control unit 53 performs the above-described control and sends an operation signal of the rotary shaft 55 to the motor 54 to open and close the gallery lid 50.

  By providing the gallery lid of this embodiment, when snowfall occurs due to a decrease in outside air temperature, the gallery lid can be closed to prevent snow from entering the switchboard. Accidents can be suppressed and safe driving is possible. In addition, when the temperature inside the panel rises due to a rise in the outside air temperature, the lid of the gallery is opened, so that the power conditioner can continue to operate without stopping and effective power generation becomes possible.

10. Power distribution board 11. Power system 12. Circuit breaker 13. Power transformer 15. Power conditioner 15. Ground fault overvoltage relay 16. Solar panel 20. Heat shield 22 ... Power distribution board base 23 ... Roof 24 ... Cooling fan 25 ... Hanging members 26, 27 ... Handle 29 ... Door 30 ... Gallery 201 ... Bending part 41 ... Fan 42 ... Heater 43 ... Cover heater 44 ... Surface heater 50 ... Gallery lid 51 ... Thermostat 52 ... Temperature measurement 53 ... Control part 54 ... Motor 55 ..Rotating shaft

Claims (4)

A distribution board for a photovoltaic power generation system,
Bending portions are formed by bending both sides of the heat shield plate arranged in all or any of the door portion, the side surface portion or the back surface portion of the power conditioner storage chamber of the switchboard storing the power conditioner, and Contact the door, side or back to form an air layer in the space,
Form a gallery on the lower side of all or any of the door part, side part or back part of the inverter storage room,
A switchboard, wherein a heater with a fan is arranged below the gallery so as to blow out toward the snow entering from the gallery . The switchboard according to claim 1,
The gallery has a plurality of arc-shaped bulging portions protruding outward and in the longitudinal direction on a metal plate, and the inside of the arc-shaped bulging portion has a vent hole. The switchboard according to claim 1 ,
The power supply of the said heater with a fan is supplied from a solar power generation system, and is used with DC power or AC power, The switchboard characterized by the above-mentioned. The switchboard according to claim 1,
The power distribution board according to claim 1, wherein a height position of the bent portion of the heat shield plate is set to be substantially the same as a height position of the gallery.

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