Patent Description:
The present disclosure relates to a rotation apparatus of a pole system for photovoltaic power generation, and more particularly, to a rotation apparatus of a pole system for photovoltaic power generation installed at a pole to provide a rotating force to a solar panel.

In general, photovoltaic power generation systems are built by installing a collection of solar panels in an array over the areas of forests, fields, fallow lands, roofs of buildings, reservoirs and salt ponds.

In case that the sites for solar power plants are forests, fields or farmlands, it is necessary to perform a pre-construction process including deforestation or civil engineering on the sites prior to installing frame structures and solar panels, causing environmental degradation such as massive loss of trees and soil. Due to these negative impacts, although forests and fields meet the optimal site requirements for solar power plants, in reality, it is not easy to build solar power plants in forests and fields.

<CIT> discloses a self-supporting photovoltaic power generation system that is installed at rooftops of buildings or banks in a non-destructive manner. The self-supporting photovoltaic power generation system includes pillar assemblies, each including at least one pillar continuously connected to each other, and light collecting plates coupled to the top of the pillar assemblies, wherein each pillar has an inclined upper surface and a filler accommodation space in which a filler is received therein.

<CIT> discloses a method for installing a photovoltaic module without occupying fields and paddies, and more particularly, a photovoltaic module that is installed in paddies, comprising a lower support, an installation fixing frame and a pillar frame to easily install the photovoltaic module in fields and paddies in the non-agricultural season after harvest and a method for installing the photovoltaic module. <CIT> further discloses a photovoltaic module having a structure in which a plurality of easy-to-install photovoltaic modules is installed by connecting an installation fixing frame of an easy-to-install photovoltaic module to a side of a protection frame of another easy-to-install photovoltaic module with a hinge means and they are folded when not in use and extended while in use.

However, the conventional photovoltaic power generation systems still cause the destruction of nature in the construction due to the large area occupied by the frame structures which support the solar panels, and accordingly its solution is required.

Additionally, in general, the conventional photovoltaic power generation systems include solar panels fixedly installed, resulting in low photovoltaic power generation efficiency. There are some systems for tracking the movement of the Sun and orientating solar panels in the photovoltaic power generation applications, but it is not easy to build the systems due to their complicated architecture and high price.

To increase the photovoltaic power generation efficiency, it is desirable to rotate solar panels along a preset path taking the amount of sunlight into account. However, in case that a
solar panel is positioned at the upper end of a pole and is simply connected to the rotation axis of a driving motor to cause it to rotate, overloads may be applied to the rotation axis of the driving motor and when external forces such as winds are applied, the connected part of the rotation axis and the solar panel is deformed or damaged and a short circuit occurs in the wiring at the rotating part, and accordingly its solution is required.

The present disclosure is designed to solve the above-described problem, and therefore the present disclosure is directed to providing a rotation apparatus of a pole system for photovoltaic power generation having a structure for rotating a solar panel using a simple driving device, thereby reducing the solar power plant installation cost, and rotating the solar panel using electricity produced from the solar panel.

The present disclosure is further directed to providing a rotation apparatus of a pole system for photovoltaic power generation for preventing deformation or damage at the connected part of the rotation apparatus and the solar panel and a short circuit in the wiring at the rotating part due to external forces such as winds.

For example, from <CIT> a solar power generating device with solar tracking system is known. The solar power generating device comprises: a fixed base <NUM> fixed to the ground; a lower frame <NUM> installed at an upper end of the fixed base <NUM> to rotate horizontally with respect to the fixed base <NUM>; a turning device <NUM> composed of inner tooth type pivot bearing <NUM> and a reduction motor <NUM>; an upper frame <NUM> installed at an upper end of the lower frame <NUM> to adjust an angle in a vertical direction; a plurality of solar cell modules <NUM> installed on an upper surface of the upper frame <NUM>; a sensor for detecting the altitude and position of the sun; a control unit for controlling the horizontal rotation angle of the turning device <NUM> and the vertical installation angle of the upper frame <NUM> according to the position and the altitude of the sun detected by the sensor. A stepped portion <NUM> is formed in the upper frame <NUM> so that wind passes through the solar cell modules <NUM> by the stepped portion <NUM>.

To achieve the above-described objective, the present disclosure provides a rotation apparatus of a pole system for photovoltaic power generation installed at an upper end of a pole to rotate a solar panel array, the rotation apparatus including a first tubular body connected to the solar panel array; a second tubular body coupled below the first tubular body and fixed to the upper end of the pole; a gear unit to transmit a rotating force to the first tubular body; a driving motor to provide the rotating force to the gear unit; and a contact part including at least three contact points installed at a coupled part of the first tubular body and the second tubular body and held in contact during a relative rotation between the first tubular body and the second tubular body to transmit power or a signal.

The solar panel array includes a plurality of solar panels connected in series, the contact part includes a first contact point, a second contact point and a third contact point, two terminals of output of all the plurality of solar panels are connected to the first contact point and the second contact point, two terminals of output of some of the plurality of solar panels are connected to the first contact point and the third contact point, an output power through the first contact point and the second contact point is supplied to a power inverter, and an output power through the first contact point and the third contact point is supplied to the driving motor.

The first contact point to the third contact point may include a pair of contact points, any one of which is a conducting ring and the other is a conducting block which contacts the conducting ring.

The conducting ring of the first contact point and the conducting ring of the second contact point may be arranged in concentric circles, and the third contact point may be installed at an upper position than the second contact point and may be disposed at an inner position in a radial direction from a rotation axis of the rotation apparatus.

The first contact point may be used as a common negative terminal to the second contact point and the third contact point.

The present disclosure may further include a bearing including an upper ring and a lower ring, wherein any one of the upper ring and the lower ring is connected to the first tubular body and the other is connected to the second tubular body, and the gear unit may be engaged with gear teeth along a periphery of the upper ring or the lower ring.

The bearing may be placed with a central axis of rotation perpendicular to ground, and may have gear teeth along the periphery of the upper ring, wherein the gear teeth are engaged with the gear unit, the gear unit may include a toothed wheel gear having a braking function to prevent gear disengagement, and the driving motor may be installed in the second tubular body.

The rotation apparatus of a pole system for photovoltaic power generation according to the present disclosure has the following effects.

Firstly, the bearing and the assembly of the first tubular body and the second tubular body make it possible to firmly support the solar panel array installed at the pole and stably transmit the rotating force without swinging caused by vibrations or external forces such as winds.

Secondly, apart from power for electricity production, it is possible to draw low power from parts of the solar panel array and efficiently supply the power to the driving motor and the printed circuit board (PCB).

Thirdly, although the diameter of the first tubular body and the second tubular body is designed at the equal or similar level to the diameter of the pole, the bearing interposed between the first tubular body and the second tubular body ensures smooth rotation and precise rotation control on a second-by-second basis.

Fourthly, the rotation apparatus achieves size reduction and simple design, leading to fast return of investment, thereby overcoming the drawbacks of the existing solar tracker, a high failure rate and high price.

Fifthly, since the solar panels are supported by the pole, the solar panels are spaced a sufficient distance apart from the ground, leading to smooth air flow, thereby suppressing the temperature rise of the solar panels, resulting in increased photovoltaic power generation efficiency.

Sixthly, in case that the sites for solar power plants are forests and fields, it is possible to maintain trees around the pole which supports the solar panels, thereby minimizing the destruction of nature.

<FIG> is a rear perspective view showing the appearance of a rotation apparatus of a pole system for photovoltaic power generation according to a preferred embodiment of the present disclosure, <FIG> is a partial enlarged diagram of the rotation apparatus in <FIG>, <FIG> is an exploded perspective view showing the internal configuration of the rotation apparatus in <FIG>, <FIG> is a perspective view showing the configuration of a driving motor and a first contact point in <FIG> and <FIG> is a cross-sectional view of <FIG>.

Referring to <FIG>, the rotation apparatus <NUM> of a pole system for photovoltaic power generation according to a preferred embodiment of the present disclosure includes a first tubular body <NUM> connected to the rear surface of a solar panel array <NUM>, a second tubular body <NUM> assembled below the first tubular body <NUM> with its lower end fixed to a pole <NUM>, a driving motor <NUM> installed in the second tubular body <NUM> to provide a rotating force to the first tubular body <NUM>, and a contact part having at least three contact points <NUM>,<NUM>,<NUM> installed at a coupled part of the first tubular body <NUM> and the second tubular body <NUM>.

The solar panel array <NUM> includes a plurality of solar panels 15a connected in series.

The solar panel array <NUM> is mounted on an inclined surface on top of the first tubular body <NUM>, and is installed at an angle to the ground. The installation angle of the solar panel array <NUM> is determined by the angle of the inclined surface.

The pole <NUM> is installed upright vertically from the ground with its lower end fixed to the ground by a fastening means such as an anchor bolt. Preferably, the pole <NUM> may be a metal tubular body having a round outer circumferential surface like a typical street light pole, and may come in a variety of other materials and shapes.

The first tubular body <NUM> is a pipe-shaped structure that includes a waterproof cover <NUM> on the obliquely inclined upper surface and has a circular circumferential surface. The waterproof cover <NUM> is detachably secured to open and close the internal space of the first tubular body <NUM>.

The second tubular body <NUM> is a pipe-shaped structure that is assembled below the first tubular body <NUM> and has a circular circumferential surface. The second tubular body <NUM> has, at the lower end, a space into which the upper end of the pole <NUM> is inserted. When the pole <NUM> is inserted, the second tubular body <NUM> is fixed to the upper end of the pole.

To improve the coupling between the rotation apparatus <NUM> and the pole <NUM> and form a structurally stable assembly, the diameter of the first tubular body <NUM> and the second tubular body <NUM> may be designed at the equal or similar level to the diameter of the pole.

A predetermined bearing may be interposed between the first tubular body <NUM> and the second tubular body <NUM>. The bearing is placed with its central axis of rotation perpendicular to the ground. The bearing includes an upper ring connected to the first tubular body <NUM> by assembly bolts to rotate with the first tubular body <NUM>, and a lower ring assembled below the upper ring and connected and fixed to the second tubular body <NUM> by bolts. A plurality of balls is arranged between the upper ring and the lower ring. The upper ring of the bearing has gear teeth at a predetermined interval along the inner circumferential surface. The gear teeth on the upper ring are engaged with a gear unit <NUM> connected to the driving motor <NUM>. Additionally, the lower ring of the bearing may have gear teeth that are engaged with some gears of the gear unit <NUM> to guide the rotation.

To minimize the occupied space, the gear unit <NUM> is positioned such that at least part of the gear unit <NUM> is inserted into the hollow of the bearing. Preferably, the gear unit <NUM> includes an assembly of planetary gears. The plurality of planetary gears is engaged with the gear teeth of the upper ring to transmit the power. Preferably, the gear unit <NUM> includes a toothed wheel gear having a braking function to prevent gear disengagement.

The driving motor <NUM> is fixed within the second tubular body <NUM>, preferably, upright coaxially with the second tubular body <NUM> to provide the rotating force to the gear unit <NUM>.

As shown in <FIG>, the first contact point <NUM>, the second contact point <NUM> and the third contact point <NUM> for power and/or signal transmission are installed at or around the coupled part or at the contact part of the first tubular body <NUM> and the second tubular body <NUM>. Although not shown in the drawing, according to a variation of the present disclosure, the rotation apparatus having more than three contact points may be provided.

The first contact point <NUM> and the second contact point <NUM> includes, respectively, a pair of contact points of conducting rings 102a,103a fixed in substantial connection to the second tubular body <NUM> and conducting blocks 102b,103b which slide in contact with the upper surface of the conducting rings 102a,103a during the relative rotation between the first tubular body <NUM> and the second tubular body <NUM>. The conducting ring 102a of the first contact point <NUM> and the conducting ring 103a of the second contact point <NUM> are arranged in concentric circles. Any one of the first contact point <NUM> and the second contact point <NUM> becomes a negative terminal and the other becomes a positive terminal. Referring to <FIG>, two terminals of the output of all the plurality of solar panels 15a are connected to the first contact point <NUM> and the second contact point <NUM>, respectively. The output power through the first contact point <NUM> and the second contact point <NUM> is supplied to a power inverter <NUM> and is used to generate power.

The third contact point <NUM> includes a pair of contact points of a conducting ring 104a which is fixed to the rotating part of the gear unit <NUM> above the first contact point <NUM> and the second contact point <NUM> to rotate with the first tubular body <NUM> and a conducting block 104b which slides in contact with the lower surface of the conducting ring 104a during the relative rotation between the first tubular body <NUM> and the second tubular body <NUM>.

The third contact point <NUM> is electrically connected to the positive terminal drawn from the output of some (for example, the output terminal of one solar panel 15a) of the plurality of solar panels 15a of the solar panel array <NUM>. The output power through the third contact point <NUM> is used as power for the operation of the driving motor <NUM> and a predetermined printed circuit board (PCB). Preferably, the third contact point <NUM> is disposed at the inner position in the radial direction from the rotation axis of the rotation apparatus, i.e., closer to the driving motor <NUM> than the second contact point <NUM> to supply the power to the driving motor <NUM> and the PCB.

Preferably, the first contact point <NUM> is used as the common negative terminal to the second contact point <NUM> and the third contact point <NUM>.

The electrical polarity assigned to the first contact point <NUM> to the third contact point <NUM> is not limited to the above-described embodiment and a variety of modifications may be made thereto.

The rotation apparatus <NUM> of a pole system for photovoltaic power generation configured as described above provides the rotating force of the driving motor <NUM> to the gear unit <NUM> to rotate the first tubular body <NUM>, causing the solar panel array <NUM> fixed to the upper end of the first tubular body <NUM> to slowly rotate. The first tubular body <NUM> rotates relative to the second tubular body <NUM> fixed to the pole <NUM> while stably supporting the solar panel 15a. The bearing interposed between the first tubular body <NUM> and the second tubular body <NUM> ensures structurally stable and smooth rotation. Preferably, the rotation path of the solar panel 15a is set to allow the solar panel 15a to be exposed to the Sun as much as possible taking the amount of sunlight into account. When the solar panel 15a rotates at a constant speed for a predetermined time, compared to the solar panel 15a placed in a fixed position facing the same direction, it is possible to increase the amount of solar power generated without using a solar tracker of a complicated structure.

Additionally, in addition to the solar panel array <NUM>, the pole system for photovoltaic power generation including the rotation apparatus <NUM> according to the present disclosure may include a vertically movable lighting unit and a vertically movable closed circuit television (CCTV) camera unit. In this case, when the lighting unit and the CCTV camera unit are lifted up as a first lifting wire and a second lifting wire are rolled up by the forward rotation of a drum embedded in a body of each unit and coupled to each body disposed at the upper part of the pole <NUM>, power may be supplied to the lighting unit and the CCTV camera unit by the contact between an upper contact point and a lower contact point embedded in each body. Here, the power for the operation of the lighting unit and the CCTV camera unit may be, for example, supplied through the first contact point.

In the rotation apparatus <NUM> of a pole system for photovoltaic power generation according to the present disclosure, the rotating force from the driving motor <NUM> in operation is transmitted to the bearing through the gear unit <NUM> to cause the upper ring of the bearing to rotate, and at the same time, the first tubular body <NUM> connected to the upper ring to rotate, so the solar panel array slowly rotates. The first tubular body <NUM> rotates relative to the second tubular body <NUM> fixed to the pole while stably supporting the solar panel array.

The gear unit <NUM> is engaged with the gear teeth along the periphery of the upper ring of the bearing to transmit the rotating force, and the upper ring is connected to the first tubular body <NUM> and rotates with the first tubular body <NUM>. The first tubular body <NUM> rotates with the solar panel array fixed to the upper surface thereof. In this instance, the gear unit <NUM> is positioned such that at least part of the gear unit <NUM> is inserted into the hollow of the bearing, thereby maximizing the space utility efficiency.

Accordingly, when the present disclosure is applied, it is possible to achieve the power source for photovoltaic power generation with high efficiency by stably rotating the solar panel 15a installed at the upper end of the pole <NUM>.

As shown in <FIG>, the output power from all the plurality of solar panels 15a is transmitted to the power inverter <NUM> through the first contact point <NUM> and the second contact point <NUM> to produce solar energy of, for example, 72V to 120V.

Additionally, the output power from some (for example, the output terminal of one solar panel 15a) of the plurality of solar panels 15a is transmitted to the driving motor <NUM> and the PCB through the first contact point <NUM> and the third contact point <NUM> to supply the driving power of, for example, 24V to 40V.

Since the diameter of the first tubular body <NUM> and the second tubular body <NUM> is much larger than the diameter of the rotation axis of the driving motor, the assembly of the first tubular body <NUM> and the second tubular body <NUM> combined with the solar panel 15a can stably transmit the rotating force, compared to the prior art that simply connects the solar panel to the rotation axis of the driving motor to rotate the solar panel. That is, it is possible to transmit the rotating force of the driving motor to the solar panel 15a without an error even though vibrations generated from the driving motor or external forces such as winds are applied.

Claim 1:
A rotation apparatus (<NUM>) of a pole system for photovoltaic power generation installed at an upper end of a pole (<NUM>) to rotate a solar panel array (<NUM>), the rotation apparatus comprising:
a first tubular body (<NUM>) connected to the solar panel array (<NUM>);
a second tubular body (<NUM>) coupled below the first tubular body (<NUM>) and fixed to the upper end of the pole (<NUM>) ;
a gear unit (<NUM>) to transmit a rotating force to the first tubular body (<NUM>); and
a driving motor (<NUM>) to provide the rotating force to the gear unit (<NUM>); characterzed in that
a contact part including at least three contact points is installed at a coupled part of the first tubular body (<NUM>) and the second tubular body (<NUM>) and held in contact during a relative rotation between the first tubular body (<NUM>) and the second tubular body (<NUM>) to transmit power or a signal,
and in that
the solar panel array (<NUM>) includes a plurality of solar panels (15a) connected in series,
wherein the contact part includes a first contact point (<NUM>), a second contact point (<NUM>) and a third contact point (<NUM>),
wherein two terminals of output of all the plurality of solar panels (15a) are connected to the first contact point (<NUM>) and the second contact point (<NUM>), wherein two terminals of output of some of the plurality of solar panels (15a) are connected to the first contact point (<NUM>) and the third contact point (<NUM>), and
wherein an output power through the first contact point (<NUM>) and the second contact point (<NUM>) is supplied to a power inverter (<NUM>), and an output power through the first contact point (<NUM>) and the third contact point (<NUM>) is supplied to the driving motor (<NUM>).