KR101721373B1 - Power converting apparatus for a floating solar power generating system - Google Patents

Abstract

The present invention relates to a water photovoltaic system with a floating power conversion device. The water photovoltaic system includes: a main floating structure floated on a water surface; a photovoltaic device installed in the main floating structure and including solar battery modules; an auxiliary floating structure floated on the water surface; a power conversion device installed in the auxiliary floating structure and converting a direct current generated from the photovoltaic device into an alternating current to boost the alternating current; and a power transmission device installed on the ground and transmitting the boosted alternating power supplied from the power conversion device to a power distribution system. According to the present invention, installation cost is greatly reduced and transmission power loss is reduced.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a water-

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-state photovoltaic power generation system to which a negative-type power-conversion apparatus is applied, and more particularly to a power-conversion apparatus that floats on a water-

At present, the problem of resource exhaustion due to the finite nature of hydrocarbons fossil energy resources, along with the increase of greenhouse gas emitted by its use, has adversely affected the global environment and threatened the survival of mankind. In addition, nuclear power generation is also threatened by the depletion of resources and the impact on the global environment and the survival of humankind in case of an accident, as seen in the case of Chernobyl and Fukushima nuclear power plants.

For the above reasons, the use of renewable energy such as solar power, wind power, and tidal power generation, which have no environmental pollution and infinite duration, is increasing all over the world. Among the renewable energies, solar energy is distributed evenly in people's inhabitants of the earth and solar energy is converted directly into electric energy, so solar power generation is the most effective, while solar energy is low in energy density and needs a large area Do.

Until now, photovoltaic power generation facilities have been installed in tidal fields, agricultural lands, and forests, but they are causing other environmental problems, such as land use and forest destruction, in addition to the pure function of using renewable energy. It is not welcomed by local residents because of contention, and is facing difficulties due to various complaints. Therefore, there is active and some research on solar power generation in desert areas and aquifers that do not compete with humans with limited land resources, and do not adversely affect the environment such as farmland destruction or deforestation.

The photovoltaic power generation system installed on a lake, a river or the sea's surface is called a photovoltaic power generation system. This system is human-friendly because it does not conflict with people and land, Reducing the rise in water temperature reduces evaporation and helps preserve fresh water and reduces fog damage in the surrounding area. In addition, it is effective to improve water quality by promoting convection of water by temperature difference caused by shade of water-condition lighting power generation system and preventing green tide. Shade by water-condition lighting power generation system protects fish resources, .

1 is a side view showing an example of a conventional water-state photovoltaic power generation system.

1, the water-state photovoltaic power generation system includes a floating structure 10 floating on a water surface such as a lake, a river, or the sea, and a floating structure 10 for preventing the floating structure 10 from moving horizontally A mounting frame 30 provided on the upper portion of the floating structure 10 and a plurality of solar cell modules M A power conversion apparatus (40) that is installed on the land and converts low-voltage direct-current power generated by the solar modules (M) into alternating current and boosts the voltage to transmit to a power distribution system of the power company 50).

The solar cell modules M of the photovoltaic power generation device 40 are divided into a plurality of groups and the solar cell modules M of each group are connected in series in accordance with the input voltage of the inverter, Each group is called a solar cell string array, and the DC power output from the unit solar cell strings of the solar cell string array is merged in the connection module.

The power conversion transmission apparatus 50 includes a plurality of inverter units 51 for converting the DC power transmitted from the connection module into AC power, a breaker unit 52 for protecting the lower end of the inverter unit 51, A transformer unit 53 for boosting the converted power from the unit 51 to a system voltage, a switch unit 54 for opening and closing the circuit, a meter unit 55 for trading power, A protection relay unit 56, a monitoring unit 57 for monitoring the operation state of the solar power generation system, and the like.

The connection modules of the photovoltaic power generation device 40 are divided into a plurality of groups, and each connection half group is connected to the inverter unit 51 of the power conversion transmission apparatus 50. Each of the connection units of the connection half group and the inverter unit 51 are connected by a cable 60 which is waterproof and flexible to transmit the combined low voltage direct current power of the connection unit to the inverter unit 51 A thick special cable is used. That is, one connection half group is connected to one inverter unit 51 by a plurality of cables 60 (the number of connection half constituting the connection half group).

In such a water-state photovoltaic power generation system, when the solar cells M of the solar cell generator 40 generate electric power by the sunlight, the DC power generated by each solar cell module M is converted into the unit solar And flows through the battery strings. The DC power flowing through the unit solar cell strings is merged in each connection cell for each solar cell string array. The combined direct current power in each connection module is output to each inverter unit 51 of the power conversion transmission apparatus 50 through the cables 60 by connection group. The inverter unit 51 converts DC power into AC power, boosts the voltage from the transformer unit 53 to the grid voltage, and transmits it to the power distribution system of the power company.

However, in the conventional water-based photovoltaic power generation system as described above, the low-voltage DC power generated in the solar cell modules M of the photovoltaic device 40 located in the water phase is merged in each connection half, A large number of special cables are used because the solar power is supplied to the inverter units 51 of the power conversion transmission apparatus 50 mounted on the land and the solar power generation apparatus is generally located at the center of the deep lake, 60 are long, and a thick cable is used to transmit the low-voltage direct current power incorporated in the connection module to the inverter unit 51. [

Accordingly, there is a problem in that the cost of the cable 60 is greatly increased when the water-condition lighting system is installed. In particular, when a water-based photovoltaic power generation system with a large power generation capacity is installed, the cost of the corresponding cable is greatly increased, so that the installation cost of the water-state photovoltaic power generation system is environmentally friendly and friendly, It is a fact that I can not.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a water-state photovoltaic power generation system which is developed to solve the above-mentioned problems, and which employs a sub-type power conversion device that greatly reduces installation cost and reduces transmission power loss.

The technical objects to be achieved by the present invention are not limited to the above-mentioned technical problems.

According to an aspect of the present invention, there is provided a water-based photovoltaic generation system including a main floating structure suspended on a water surface, a photovoltaic power generation device installed on the main floating structure, An auxiliary floating structure suspended on the water surface; a power conversion device installed on the auxiliary floating structure for converting direct current power generated by the solar power generation device into alternating current and boosting it to a high voltage; and a power conversion device installed on the land, Voltage AC power supplied from the high-voltage alternating-current power supply system to the power distribution system.

Specifically, the power changing apparatus includes an inverter unit and a transformer unit.

Specifically, the power conversion device and the power transmission device are electrically connected by a high voltage cable.

And a protective barrier coupled to the edge of the base plate in a vertical direction.

Specifically, the power conversion device is housed in a protective house, and the protective house includes at least one of a closed type, a circulating type, or a warming type so as to protect the power conversion device from heat, cold or moisture, The house is characterized by comprising at least one of an inclined roof or a flat roof or a domed roof or a container or a steel box.

Specifically, the power conversion device is mounted on the impact mount.

Specifically, the impact mount is characterized in that a mount is attached to upper and lower portions of a plurality of impact mounts to make a dustproof band.

As described above, the water-state photovoltaic power generation system to which the sub-type power conversion apparatus of the present invention is applied is characterized in that the power conversion apparatus is located in the waterfront adjacent to the solar power generation apparatus and the power transmission apparatus is installed on the land, The length of the low-voltage cables for transmitting the power to the inverter unit of the power conversion apparatus can be shortened, and the high voltage is supplied from the power conversion apparatus to the power transmission apparatus installed on the ground via the high voltage cable, It is effective.

Further, the present invention is characterized in that the power conversion apparatus is located in the waterfront adjacent to the solar power generation apparatus, the power transmission apparatus is installed on the land, and the length of the low voltage cables transmitting the direct current power generated from the solar power generation apparatus to the inverter unit of the power conversion apparatus is short (3 strands in the case of 3-phase power), the use of the low-voltage cables is greatly reduced, and the installation cost of the water-state power generation system is reduced There is a saving effect.

In addition, since low-voltage cables can be wired to water pipes instead of water, it is possible to freely select cables and facilitate wiring work and maintenance.

In addition, the shock mount can be installed at the lower part of the power conversion device to safely protect the power conversion device by absorbing shocks in the event of collision of various floating materials and ships during floods and high waves, And the auxiliary floating structure can be freely fixed at a fixed height according to the water depth through the lift device. Therefore, it is possible to safely operate and manage the power conversion device irrespective of the water level.

1 is a side view showing an example of a water-state photovoltaic power generation system according to the prior art.
2 is a side view illustrating a water-state photovoltaic power generation system to which a negative power converter according to an embodiment of the present invention is applied;
3 is a side view showing a first embodiment of the negative type power conversion apparatus shown in FIG.
4 is a side view showing a second embodiment of the negative type power conversion apparatus shown in FIG.
Fig. 5 is a conceptual diagram showing that the negative type power conversion apparatus shown in Fig. 1 is installed on a shock mount.
6 is a diagram illustrating various embodiments of the impact mount shown in FIG.
FIG. 7 is a side view showing a first embodiment for placing the sub-type power conversion apparatus shown in FIG. 1 in the water phase.
Fig. 8 is a side view showing a second embodiment of placing the sub-type power conversion apparatus shown in Fig. 1 in the water phase.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference symbols whenever possible. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 2 is a side view illustrating a water-state photovoltaic power generation system to which the sub-type power conversion apparatus according to an embodiment of the present invention is applied. In an embodiment of the water-state photovoltaic power generation system to which the sub- A main floating structure 100, a photovoltaic power generation device 200, an auxiliary floating structure 300, a power conversion device 400, and a power transmission device 500.

The main suspended structure 100 floats on the water surface of an attraction such as a river, a lake, a dam, or the sea. The main floating structure 100 includes a plurality of buoyant members 110 and a base frame 120 coupled to the top of the buoyant members 110. The buoyant members 110 may include a plurality of buoyant members 110, The buoyancy material 110 may be a material in which the inner space floats in water, such as an empty container or a styrofoam. Preferably, the mooring device 130 is connected to the main suspended structure 100. The mooring device 130 not only restricts the movement of the main floating structure 100 in the horizontal direction by the flow of wind or water, but also allows the main floating structure 100 to freely move up and down according to the change of the height of the water surface. The mooring device 130 includes an anchor 131 fixed to the bottom of a river or a lake and a rope 132 connected to the anchor 131 and extending over the main floating structure 100. [ And a rope length adjusting device 133 connected to an end of the rope 132. [ The mooring device 130 may be variously implemented.

The solar cell apparatus 200 includes solar cell modules M. The photovoltaic device 200 is installed in the main flotation structure 100. The mounting frame 210 is installed on the base frame 120 of the main suspended structure 100 and the solar cell modules M are installed on the mounting frame 210. The low voltage cable 220 supplies the power generated in the solar power generator 200 to the power inverter 400. The unit solar cell strings connecting the solar cell modules in series are merged in the connection module. A predetermined number of solar cell modules M are connected to the unit solar cell strings. The connection modules also consist of the set number. The unit solar cell strings, the connection modules, are determined by the inverter input voltage and the generating capacity of the solar power generator.

The auxiliary floating structure 300 floats on the water surface. It is preferable that the auxiliary floating structure 300 is located adjacent to the main floating structure 100. 3 and 4, the auxiliary floating structure 300 is coupled to the upper portions of the buoyant bodies 310 and the plurality of buoyant bodies 310, A base plate 320 on which a base plate 400 is mounted and a protection barrier 330 vertically coupled to an edge of the base plate 320. The buoyant body 310 may be a member in which the inner space is suspended in water such as an empty vessel or a styrofoam. Another embodiment of the auxiliary floating structure 300 includes a protective house 340 surrounding the power conversion device 400. In another embodiment of the auxiliary suspended structure 300, the auxiliary suspended structure 300 may be a barge.

 The power conversion apparatus 400 converts the DC current generated in the photovoltaic device 200 into AC and boosts the DC current. The power conversion apparatus 400 preferably includes an inverter unit 410 and a transformer unit 430 and further includes a switch unit 440.

The inverter unit 410 converts the low voltage direct current supplied by the low voltage cables 230 from the photovoltaic device 200 into alternating current power. A plurality of inverter units 410 are provided in accordance with the capacity of the solar power generation apparatus 200.

The transformer unit 430 boosts the AC power converted by the inverter unit 410 to a high voltage. Here, the high voltage does not refer to the range of the high voltage based on the voltage classification standard of each country but means the voltage higher than the output voltage of the inverter unit.

The breaker unit 420 is connected to the output side of the inverter unit 410 or the transformer unit 430 and protects the device by interrupting the current when an excessive current flows into the inverter unit 410 or the transformer unit 430, Allows the circuit to be disconnected during inspection.

The switch unit 440 also protects the circuit while opening and closing the circuit when abnormal power flows to the circuit, and opens or closes the circuit to supply or cut off power to the on-shore transmission device. The power inverter 400 preferably further includes a monitoring unit.

The power transmission apparatus 500 is installed on the land. The power transmission apparatus 500 directly or alternately boosts the high-voltage alternating-current power supplied from the power conversion apparatus 400 to transmit it to the power distribution system. The power transmission apparatus 500 includes a meter unit 510 for trading power, a protection relay unit 520 for protection cooperation with the power distribution system, and the like.

It is preferable that the power conversion device 400 and the power transmission device 500 are connected by a high voltage cable 450. That is, the high voltage power boosted by the transformer unit 430 of the power inverter 400 is transmitted to the power transmission apparatus 500 through a set of high voltage cables 450, and the high voltage power transmitted to the power transmission apparatus 500 To the power distribution system via the meter unit 510.

Fig. 3 is a side view showing a first embodiment of the negative type power conversion apparatus shown in Fig. 1, wherein the first embodiment of the negative type power conversion apparatus constituting the water status positive power generation system according to the present invention comprises: The auxiliary floating structure 300 includes a base plate 320 on which the power conversion device 400 and the power conversion device 400 are installed and a protection house 340 for housing the power conversion device 400.

There is always a risk that the water surface of the water surface will wave, and when a storm due to a typhoon or the like occurs, there is a risk that a large surge occurs and the water splashes directly on the power conversion apparatus 400, or scattered water penetrates into the power conversion apparatus 400. If water contacts the inverter unit 410 and the transformer unit 430 constituting the power inverter 400, there is a possibility that the inverter breaks off and the breaker is cut off or insulation breakdown is caused and the inverter is damaged. The protective house 340 may be made of various materials such as a flat roof and a dome roof in addition to the inclined roof. A container or a steel box may be used as a substitute for the protection house 340.

In addition, the protection house 340 may include any one or more of a closed type, a circulation type, or a thermal insulation type so as to protect the power conversion device from heat, cold, or moisture.

4 is a side view showing a second embodiment of the negative type power conversion apparatus shown in FIG.

And a protective barrier 330 is further provided on the outer periphery of the base plate 320 so that a large wave caused by a storm does not strike the direct protection house 340. It is preferable to drill a plurality of small holes so that the overflowed water is discharged to the lower portion of the protective barrier 330. It is preferable that the protective barrier 330 is installed at a height of 1200 mm or more so as to prevent a person from falling down during maintenance and inspection.

5 is a conceptual view showing an embodiment in which the sub-type power conversion apparatus constituting the water-state photovoltaic power generation system according to the present invention is installed on the impact mount. The power conversion apparatus is installed on the impact mount 360. [ On the ground, the power converter is installed without a separate anti-vibration device since it is a stopper without mechanical movement. However, when the power conversion device is installed in the suspended structure suspended on the water surface of the lake, it is necessary to protect the power conversion device 400 from impact due to waves, impact due to floating materials in a flood, impact from a ship or the like. The wobble is always wobbling and the power converter 400 mounted on the floating structure continues to receive large and small impacts in various directions. When the floating structure is impacted, the impact is transferred to the power converter and the bolts used for assembly are loosened. In addition, when the solid insulation material of the inverter unit 410 and the transformer unit 430 constituting the electric power conversion device are finely cracked and the cracks are gradually enlarged and finally the mechanical strength is lost and the insulation distance can not be maintained, Resulting in breakage of the insulation.

The size of the wave at the lake is affected by the creepage distance and wind intensity. The larger the creepage distance, the greater the wave is. In other words, the larger the lake and the higher the wind speed, the larger the waves. The floating structure has a linear elastic behavior with respect to the wind load, which means that repeated impacts are applied in the horizontal direction. Therefore, it can be seen that impacts in the horizontal direction due to up and down impact by the waves and elastic behavior are repeatedly applied to the power conversion device mounted on the floating structure. When a storm, such as a typhoon, is blowing, a large wave is generated and an elastic behavior is also increased, so that a large impact is repeatedly applied to the power conversion device in various directions.

The power conversion device 400 mounted on the floating structure must be installed on the impact mount 360 and the impact mount 360 is structured such that the movement of the impact mount 360 is limited in the vertical direction so that the power conversion device is not conducted due to a high- Should be. The impact mount 360 is designed to not only be subjected to a horizontal impact due to elastic behavior but also to a shock caused by a collision of a floating material at the time of a flood and an impact due to a collision between a maintenance ship Shall be provided with sufficient strength. The impact mounts (360) should be selected in consideration of the expected impact strength, displacement and frequency, and these depend on the area of installation and the area of the lake. do. In addition to the above-described methods, the impact mount 360 may be provided with a plurality of shock mounts 360 at upper and lower sides thereof to form a dustproof band, and a power conversion device may be provided thereon. The impact mount 360 may be installed individually for each device constituting the power conversion apparatus 400, and each device may be installed on one frame and the impact mount 360 may be installed under the frame. The impact mount 360 may be an anti-vibration mat or a dust-proof pad. The impact mount 360 can be installed in various ways.

6A is a side view showing various embodiments of the impact mount to be applied to the sub-type power conversion apparatus constituting the water-state photovoltaic power generation system according to the present invention, wherein FIG. 6A shows a steel plate 361a on the spring 362, Lt; RTI ID = 0.0 > 360a < / RTI > 6B shows a shock mount 360b having a leveling bolt 363 coupled to an upper portion of a rubber 364 having a predetermined thickness and a steel plate 365b coupled to the lower portion. In addition, the impact mount 360 may be fabricated using air, or may be fabricated using a combination of spring, rubber, and air. The impact mounts 360 may be used alone or in combination. The impact mount 360 can be configured in a variety of ways.

The mooring device 130 is connected to the auxiliary floating structure 300 on which the power conversion device 400 is mounted. The mooring device 130 not only restricts the movement of the auxiliary floating structure 300 in the horizontal direction by the flow of wind or water, but also permits the auxiliary floating structure 300 to freely move up and down according to the height change of the water surface.

FIG. 7 is a side view showing a first embodiment in which the sub-type power conversion apparatus shown in FIG. 1 is placed in a water phase. The first embodiment of the mooring apparatus 130 includes an anchor 131 A rope 132 connected to the anchor 131 and connected to the auxiliary floating structure 300 and a rope length adjusting device 133 for adjusting the expansion and contraction of the rope 132. As a method of controlling the expansion and contraction of the rope 132, a weight can be attached to one end of the rope 132 or a hoisting machine can be provided. It is preferable that the first embodiment of the mooring device 130 is installed in a dam or sea or the like having a deep water depth.

FIG. 8 is a side view of a second embodiment of placing the sub-type power conversion apparatus shown in FIG. 1 on the aquifer, wherein the second embodiment of the mooring apparatus 130 allows the mooring apparatus 130 to be secured to the underwater ground And a lift device connecting the plurality of columns to the auxiliary floating structure so that the auxiliary floating structure moves up and down according to the height of the water surface. The lifting device 355 may be a roller mechanism that moves up and down along the guide member. The platform can be configured in various ways. The elevating device 355 is desirably configured to be able to attach and detach the auxiliary floating structure 300 so that the auxiliary floating structure 300 or the power conversion device 400 can be moved to the water level and maintained. Further, it is preferable that the lifting device 355 includes fixing means capable of fixing the auxiliary floating structure 300 at a predetermined height. It is preferable that the second embodiment of the mooring device 130 is installed on a reservoir or a seawater having a low depth of water.

The main suspended structure 100 and the auxiliary suspended structure 300 may be connected to each other by connecting means (not shown). The connecting means may be a rope or a rod member.

Hereinafter, the operation and effects of the water-state photovoltaic power generation system according to the present invention will be described.

First, when power is generated in the solar cell modules M of the solar cell generator 200 installed in the main floating structure 100 by the sunlight, the DC power generated in each solar cell module M is divided into units And flows through the solar cell strings 201. The DC power flowing through the unit solar cell strings 201 is merged in each connecting cell 220 for each solar cell string array A. [ The DC power combined in each connection block 220 is supplied to each inverter unit 410 of the power inverter 400 located in the airstream so as to be adjacent to the solar power generator 200 through the low voltage cables 230 Is transmitted. Inverter unit 410 converts the direct current power into alternating current power and the transformer unit 430 boosts it to high voltage. The high-voltage alternating-current power converted in the power conversion apparatus 400 is transmitted to the power transmission apparatus 500 through the high-voltage cable 450 and the high-voltage current passing through the power transmission apparatus 500 is transmitted to the power distribution system of the power company.

The present invention is characterized in that the power conversion apparatus 400 is positioned adjacent to the solar power generation apparatus 200 so that the direct current power generated from the solar power generation apparatus 200 is transmitted to the inverter unit 410 of the power conversion apparatus 400 The length of the low-voltage cables 230 is shortened to reduce the cost of the cable, and the low-voltage cables 230 can be wired to the water pipe rather than the water, thereby facilitating the wiring work. In addition, the power generated from the photovoltaic power generation device is converted from the power conversion device 400 to the high-voltage alternating current and is transmitted to the power transmission device 500 installed on the ground via the high-voltage cable 450, thereby reducing power loss.

In addition, the present invention provides a power conversion device on the impact mount 360 to mitigate the impact in the horizontal direction due to the upward and downward impacts and the elastic behavior due to the high waves in the event of a storm, And the shock caused by the collision of the ship for maintenance or the ship for fishing can be alleviated. Installing a power converter on a shock mount ensures the life of the power converter unit.

 Table 1 below illustrates the comparison of the power cable requirements for the conventional water-state photovoltaic power generation system and the water-state photovoltaic power generation system according to the present invention.

Condition 1. Line ball 800M 2. Allowable voltage drop 3%
3. Split connection capacity 110 Kw Voltage drop calculation formula: E = A * L * 1/1000 * S
A; Single phase 2 wire type = 35.6 3 phase 3 wire type = 30.8 3 phase 4 wire type = 17.8 (Single phase 3 wire type)
E: Voltage drop (V) L: Distance from secondary side of transformer or lead wire connection point (M)
I: Current (A) S: Cross section of wire (MM2) Generation capacity 5Mwp 20Mwp Transmission voltage DC 716V Three-phase AC 22900V DC 716V Three-phase AC 22900V Required cable UW-3PN Cable
240sq / 1C 90 strands F-CNCV-W Cable
60sq / 1C 3 strands UW-3PN Cable
240sq / 1C 360 strands F-CNCV-W Cable
240sq / 1C 3 strands Required piping material ELP PIPE 80C
40LINE ELP PIPE 125C
1LINE ELP PIPE 80C
160LINE ELP PIPE 80C
1LINE

Table 1 shows the values calculated by comparing the present invention with the conventional water condition lighting power generation system in the case of 5 MW, which is a middle scale facility and 20 MW, which is a large scale facility. The voltage of the DC low- The voltage of the high voltage AC power of the power conversion equipment of the present invention is set to 22900 V, which is the power supply distribution system voltage of the Korean power company, and the power cable length is equal to or less than 3% of the allowable voltage drop of 800M Respectively.

As shown in Table 1, in the conventional water-state photovoltaic power generation system, a power cable of 240 mm 2 and a protective conduit of 80 mm in diameter is required in a 5 MW power generating plant, while in the water-state photovoltaic power generation system according to the present invention, The protective conduit also only needs one 125mm diameter. In addition, in the 20 MW power plant, the power cable requires 240 mm2 360 strands and the protective conduit requires 160 mm in diameter, whereas the water-state photovoltaic power generation system according to the present invention requires only one 400 mm2 3 stranded protective conduit with a diameter of 200 mm .

As described above, in the water-state photovoltaic power generation system to which the sub-type power conversion apparatus of the present invention is applied, since the power conversion apparatus is located in the waterfront adjacent to the solar power generation apparatus and the power transmission apparatus is installed on the land, The length of the low-voltage cables for transmitting the power to the inverter unit of the power conversion apparatus can be shortened, and the high voltage is supplied from the power conversion apparatus to the power transmission apparatus installed on the ground via the high voltage cable, It is effective.

Further, the present invention is characterized in that the power conversion apparatus is located in the waterfront adjacent to the solar power generation apparatus, the power transmission apparatus is installed on the land, and the length of the low voltage cables transmitting the direct current power generated from the solar power generation apparatus to the inverter unit of the power conversion apparatus is short (3 strands in the case of 3-phase power), the use of the low-voltage cables is greatly reduced, and the installation cost of the water-state power generation system is reduced There is a saving effect.

In addition, since low-voltage cables can be wired to water pipes instead of water, it is possible to freely select cables and facilitate wiring work and maintenance.

In addition, the shock mount can be installed at the lower part of the power conversion device to safely protect the power conversion device by absorbing shocks in the event of collision of various floating materials and ships during floods and high waves, And the auxiliary floating structure can be freely fixed at a fixed height according to the water depth through the lift device. Therefore, it is possible to safely operate and manage the power conversion device irrespective of the water level.

The water-state photovoltaic power generation system to which the sub-type power conversion apparatus according to an embodiment of the present invention is applied is not limited to the configuration and operation of the embodiments described above. The embodiments may be configured so that all or some of the embodiments may be selectively combined so that various modifications may be made.

10: Floating structure 20: Mooring device
30: mounting frame 40: photovoltaic device
50: power conversion transmission device 51: inverter unit
52: breaker unit 53: transformer unit
54: switchgear unit 55: meter unit
56: Protection relay unit 57: Monitoring unit
60: Cable
100: main floating structure 110: buoyant material
120: base frame 130: mooring device
131: anchor 132: rope
133: rope length adjuster 200: photovoltaic generator
210: mounting frame 220: low voltage cable
300: auxiliary floating structure 310: buoyant body
320: base plate 330: protective barrier
340: Protective House 350: Column
355: lifting device 360a, 360b: shock mount
361a, 361b: steel plate 362: spring
363: Leveling bolts 364: Rubber
400: power converter 410: inverter unit
420: breaker unit 430: transformer unit
440: switchgear unit 450: high voltage cable
500: transmission device 510: meter unit
530: Protection relay unit M: Solar module

Claims (7)

A main floating structure suspended on the water surface; A photovoltaic device installed in the main suspended structure and including solar battery modules; An auxiliary floating structure suspended on the surface of water; A power converter installed in the auxiliary floating structure and converting the direct current power generated by the photovoltaic power generator into alternating current and boosting it to a high voltage; And a power transmission device installed on the land and transmitting the high-voltage alternating-current power supplied from the power conversion device to the power distribution system,
The power conversion device includes an inverter unit, a transformer unit, Wherein the power conversion device is housed in a protective house and the protective house is in any one or more of a closed type, a circulating type, or a warming type so as to protect the power conversion device from heat, cold or moisture Including,
And a protective barrier vertically coupled to a base plate edge of the power conversion device,
The protective house may be in the form of an oblique roof or a flat roof or a domed roof or a container or a steel box,
The auxiliary lifting structure includes a lifting device that connects the lifting structure and the plurality of columns so as to move up and down. The lifting device is capable of attaching and detaching the auxiliary lifting structure so that the auxiliary lifting structure or the power converting device can be moved to the water level for maintenance. And,
The power conversion device is mounted on a shock mount, and the shock mount is made of a vibration proof band by attaching a mount to upper and lower portions of a plurality of impact mounts,
The shock mount is composed of a spring, a leveling bolt, a rubber plate, and a steel plate, and is selected in consideration of the strength, displacement and frequency of the impact, Which is capable of being protected from impacts by the < RTI ID = 0.0 >
A plurality of small holes are formed in the lower portion of the protective barrier so as to allow the overflowing water to escape, and the height of the protective barrier is increased by 1200 mm or more in order to prevent a person from falling during maintenance and inspection,
Wherein the power conversion device and the power transmission device are electrically connected by a high voltage cable. delete delete delete delete delete delete

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