cubicle

Abstract

To improve cooling performance of a GFI and a transformer located within a cubicle.SOLUTION: A cubicle, which houses a device for supplying power to the outside, allows a grid forming inverter to be placed on a back side of the cubicle, allows a high-voltage transformer to be placed on a front side of the cubicle, and includes galleries on a front and a side of the cubicle. Outside air taken in from the galleries provided on the front cools the high-voltage transformer and outside air taken in from the galleries provided on the side cools the grid forming inverter.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cubicle. [Background technology]

[0002] In conventional power systems, synchronous power sources such as thermal power plants have inertia and have contributed to maintaining power quality (frequency, voltage). However, as the amount of solar and wind power generation connected to the grid via inverters, which do not have inertia, increases, the inertia of the power system decreases, and the risk of a large-scale blackout occurring in the event of a power supply failure is becoming a problem.

[0003] To solve this problem, a grid forming inverter (GFI), sometimes called a power conditioning system (PCS), is used, which has a control function that simulates inertial force on the power grid.

[0004] GFIs are used together with transformers and are often installed outdoors, which exposes them to wind and rain, leading to problems of electrical leakage and deterioration. For this reason, there is a demand for cubicles to house GFIs and transformers.

[0005] Patent Document 1 discloses a grid-connected device that includes a power conditioner having an inverter and a reactor that converts generated DC power into AC power, a step-up transformer that converts the AC power output from the power conditioner into high-voltage power, and a circuit breaker that is placed between the step-up transformer and an existing high-voltage power system, and that supplies the generated power to the high-voltage power system.The grid-connected device has a ventilation fan placed in the ceiling of the device, a heat-shielding duct placed inside the wall of the device, and an intake opening placed at the bottom of the wall, and the heat-shielding duct rises from the bottom upward along the entire surface or part of the wall and is bent at the ceiling towards the ventilation fan. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Patent Publication No. 2017-229173 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention aims to improve the cooling performance of a GFI and a transformer arranged in a cubicle. [Means for solving the problem]

[0008] The above object is achieved by a cubicle that stores equipment that supplies power to the outside, in which a grid-forming inverter can be placed on the rear side of the cubicle and a high-voltage transformer can be placed on the front side of the cubicle, and which has galleries on the front and sides of the cubicle, so that outside air taken in from the gallery on the front cools the high-voltage transformer and outside air taken in from the gallery on the side cools the grid-forming inverter. [Effects of the Invention]

[0009] This makes it possible to efficiently dissipate heat generated by the GFI and transformer within the cubicle. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a front view of a cubicle according to an embodiment of the present invention; [Figure 2] 1 is a rear view of a cubicle according to an embodiment of the present invention; [Figure 3] FIG. 2 is a right side view of a cubicle according to an embodiment of the present invention. [Figure 4] FIG. 2 is a left side view of a cubicle according to an embodiment of the present invention. [Figure 5] 1 is an example of a front equipment layout diagram of a cubicle in an embodiment of the present invention. [Figure 6] 1 is an example of an equipment layout diagram on the right side of a cubicle according to an embodiment of the present invention. [Figure 7] 1 is an example of a rear equipment layout diagram of a cubicle in an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] Grid-forming inverters (hereinafter referred to as GFIs) are power conversion devices that connect DC power sources such as solar power generation and storage batteries to AC power grids.

[0012] The GFI operates as a voltage source that controls the frequency and amplitude of the voltage. For example, if the GFI reduces the frequency of the voltage waveform, the GFI's voltage phase lags relative to the AC power grid, reducing the active power output.

[0013] Furthermore, because the power cable connecting the GFI to the grid is inductive, when the GFI lowers the amplitude of the voltage waveform relative to the voltage at the interconnection point, the reactive power output decreases.

[0014] At this time, the GFI controls the voltage frequency to be lowered in proportion to the magnitude of the active power output by the GFI, and the voltage amplitude to be lowered in proportion to the magnitude of the reactive power output by the GFI, thereby autonomously adjusting the magnitude of its output between itself and other GFIs and synchronous generators connected to the power grid.

[0015] This method of sharing output based on the voltage frequency difference or voltage amplitude difference between power sources is called droop control, and is expected to be a means of improving the stability of power systems as renewable energy (hereinafter referred to as "renewable energy") connected via power conversion devices is expected to increase further and synchronous generators will be reduced in the future.

[0016] Such GFI control is often performed together with the transformer, and the transformer and GFI are housed in the same cubicle to control the GFI.

[0017] In this case, both the GFI and the transformer generate heat during operation. Furthermore, cubicles are often installed outdoors near solar power generation equipment, etc., and it is necessary to prevent these devices from overheating due to sunlight for stable operation.

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Example]

[0019] FIG. 1 is an example of a front view of a cubicle according to an embodiment of the present invention.

[0020] Three galleries are placed on each front door, increasing the amount of air intake from the front of the cubicle, and air heated by the heat of the equipment is exhausted by Fan 2 located on the upper left side, improving air flow and cooling performance.

[0021] At the front, there are two doors attached to the housing with hinges on the sides, allowing access to the equipment placed inside the cubicle from the front, and the doors can be opened from the center to both sides.

[0022] This structure allows access to the switches for the equipment required for daily operation, the high-voltage transformer 10, and the storage battery 11 from the front.

[0023] FIG. 2 is an example of a rear view of a cubicle in an embodiment of the present invention.

[0024] At the back of the cubicle, there are two doors attached to the housing with hinges on the sides, and they can be opened from the center to either side. The doors do not have galleries.

[0025] This door allows operations necessary for the daily operation of low-voltage powered equipment such as GFI.

[0026] In addition, by not providing a gallery on the back, it is possible to protect the GFI, which requires more dust-proofing measures.Furthermore, by adding a purifier or dust measuring device, further dust-proofing measures are possible.

[0027] FIG. 3 is an example of a right side view of a cubicle according to an embodiment of the present invention.

[0028] A maintenance door 5 is provided in the center, allowing personnel to access a maintenance passage 6 provided between the high-voltage equipment side and the low-voltage equipment side provided in the cubicle.

[0029] A gallery 3 is provided at the bottom left (front side) of the right side, allowing outside air to be taken in to cool the high-voltage equipment.

[0030] FIG. 4 is an example of a left side view of a cubicle according to an embodiment of the present invention.

[0031] Fans 2 are attached to the upper left and right sides of the left side, allowing the air used to cool the equipment inside the cubicle to be exhausted to the outside.

[0032] Gallery 3 is provided at the bottom right of the left side, allowing the air used to cool the high-voltage equipment to be exhausted to the outside.

[0033] FIG. 5 is an example of a front equipment layout diagram of a cubicle in an embodiment of the present invention.

[0034] A high-voltage transformer 10, which generates the most heat in the cubicle, is located at the bottom left, and a storage battery 11 is located at the bottom right. The storage battery 11 may not be necessary depending on the operation of the cubicle.

[0035] The high-voltage transformer 10 is cooled by outside air taken in through the gallery 3 located at the bottom of the left side, and the air warmed by the heat of the high-voltage transformer 10 rises and is forcibly exhausted to the outside by the fan 2. This air flow is the air flow indicated by (2).

[0036] The storage battery 11 is cooled by outside air taken in through the gallery 3 provided at the bottom of the right side, and the air warmed by the heat of the storage battery 11 rises, passes through the top of the cubicle, and is exhausted by the fan 2.

[0037] FIG. 6 is an example of an equipment layout diagram on the right side of a cubicle in an embodiment of the present invention.

[0038] From the front left, there is a storage battery 11 and a high-voltage transformer 10, and on the right there is a low-voltage transformer 13 at the bottom, a GFI at the top, and a reactor 12 near the center that changes the power factor of the electricity from the GFI.

[0039] A maintenance passage 6 inside the cubicle can be accessed from a central maintenance door 5, allowing maintenance work such as collecting waste oil from the high-voltage transformer and replacing fuses to be carried out.

[0040] By separating and arranging the high-voltage equipment on the left side of the maintenance door 5 and the low-voltage equipment on the right side, it is possible to reduce electrical noise between the equipment and the impact of heat generated by the high-voltage equipment on the low-voltage equipment, as well as to take care not to get an electric shock if a person comes into contact with the high-voltage equipment, which may improve maintenance efficiency.

[0041] The maintenance passage 6 does not necessarily have to be provided, and if the maintenance passage 6 is not provided, a compact cubicle with good space efficiency can be provided.

[0042] A ventilation opening is also provided at the top front of the cubicle, and the air taken in from the front gallery 3, which cools the high-voltage transformer 10 and storage battery 11, is then discharged from the upper ventilation opening by the airflow (3).

[0043] FIG. 7 is an example of a rear equipment layout diagram of a cubicle in an embodiment of the present invention.

[0044] The GFI is located at the top of the back, and by opening the rear door, workers can operate the GFI while standing.

[0045] The low-voltage equipment located at the rear of the cubicle generates less heat than the high-voltage equipment, but is cooled by the air currents (4) and (5) generated by the outside air coming from the galleries 3 on the left and right sides, and the heated air is exhausted by the fan 2 on the rear side.

[0046] By providing two fans 2 on the upper left side, it is possible to efficiently exhaust air from the front side where high-pressure equipment is installed and the rear side where low-pressure equipment is installed. [Explanation of symbols]

[0047] 1 cubicle, 2 fan, 3 gallery, 5 maintenance door, 6 maintenance passage, 10 high-voltage transformer, 11 storage battery, 12 reactor, 13 low-voltage transformer, 14 GFI

Claims

1. A cubicle for storing equipment that supplies power to the outside, A grid forming inverter can be placed on the rear side of the cubicle, A high-voltage transformer can be arranged on the front side of the cubicle, The cubicle has galleries on the front and sides thereof, and outside air taken in from the gallery on the front cools the high-voltage transformer, and outside air taken in from the gallery on the side cools the grid forming inverter.

2. 2. The cubicle according to claim 1, The cubicle has a door on the rear surface thereof, and the grid forming inverter can be operated through the door on the rear surface.

3. 2. The cubicle according to claim 1, The cubicle has galleries on the left and right sides. A cubicle in which the amount of air taken in from the gallery at the front is greater than the amount of air taken in from either the gallery on the left side or the gallery on the right side.

4. 2. The cubicle according to claim 1, a reactor that changes the power factor of the power from the grid forming inverter; a maintenance passageway through which people can pass is provided between the high-voltage transformer and the reactor; the reactor and the grid forming inverter are arranged on the same side across a passage, The high-voltage transformer is a cubicle located on the opposite side of the reactor across a maintenance passage.

5. 2. The cubicle according to claim 1, A cubicle in which a storage battery can be placed on the front side of the cubicle.

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