JP2005106432A - Solar light collection and heat collection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a tracking type solar light collection and heat collection device capable of obtaining high heat collection ratio in a relatively small installation area. <P>SOLUTION: The solar light collection and heat collection device is equipped with a parabola main reflection mirror 1 which is mirror-finished to an extent that a reflecting face allows specular reflection for solar light and a heat collection body 3 integrally provided with the parabola main reflection mirror to be positioned in a focal area of solar light falling on its reflecting face. A mounting mechanism 4 for supporting the parabola main reflecting mirror so that the incident direction of solar light to the reflecting face of the parabola main reflecting mirror can be adjusted to direct in a predetermined azimuthal angle region and a predetermined elevation angle while the parabola main reflecting mirror is integrated with the heat collection body. When the incident direction to the reflecting face of the parabola main reflecting mirror is directed to a direction of solar light on the mounting mechanism, the solar light is collected to the heat collection body 3 and converted into thermal energy to achieve heat collection. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to solar heat collection in a solar heat utilization system.

The radiation energy of the sun in Japan is about 1 KW / m ^{2 on the} ground surface, and its energy density is low.
Therefore, as a solar energy utilization system, a heat collector using optical means for capturing solar thermal energy has been proposed (see, for example, Patent Document 1).
Japanese Examined Patent Publication No. 61-2852 Japanese Patent Laid-Open No. 10-281565

  Conventionally, the solar heat collection, the position of the sun moves from moment to moment on the orbit, so that tracking the solar orbit from any position on the ground to collect heat "tracking type" and "non-tracking type" There are two main types: fixed type.

The fixed type has a low energy density on the ground surface as low as about 1 kW / m ^2, and therefore requires a relatively large land area to increase the amount of heat collected.
For this reason, expansion of the heat collection area has been attempted, but since the heat transport path for the amount of heat collected as the area is expanded and the heat loss increases, the overall efficiency of the system is significantly reduced and the cost is reduced. The expansion of solar power was unavoidable and greatly hindered the development of solar heat utilization system.
Moreover, as the fixed type, a flat plate type shown in FIG. 4 (a) by a non-condensing method and a side mirror type shown in FIG. 4 (b) by a condensing method have been tried. Because of the low temperature, if a high heat temperature cannot be obtained and the amount of heat collection is intended to increase, the heat collection area has to be expanded. In FIG. 4A, 7 is a flat panel, 8 is a heat collecting plate, 9 is a conduit through which a fluid flows, 10 is a heat collecting tube, 11 is a glass plate, and 12 is a heat insulating material. In FIG. 4B, 7 is a flat panel, and 13 is a plane mirror.

  On the other hand, in the tracking type, the “Fresnel lens type” shown in FIG. 5 and the “cylindrical parabolic mirror type” shown in FIG. A high energy density is not obtained for the tracking of about ˜40, and a great effect is not obtained. In FIG. 5, 14 is a Fresnel lens, and 15 is a heat collecting part. In FIG. 6, 16 is a reflecting mirror (cylindrical parabolic mirror), 17 is a heat collecting tube, 18 is a glass cylinder, 19 is a fluid inlet, and 20 is a fluid outlet.

  Further, even with a technique using a large-sized condensing reflector such as the “rotating parabolic mirror type” shown in FIG. 7 by the point condensing method, the heat collection ratio is about 100 to 500, and further enlargement is attempted. Although a high heat collection ratio of 1000 times or more has been obtained, all of them require a large land area and large-scale equipment, which necessitates a cost expansion, impeding the practical development of a solar heat utilization system. In FIG. 7, reference numeral 21 denotes a reflecting mirror (rotating parabolic mirror).

  The object of the present invention is to eliminate the disadvantage that the conventional method requires a large land area for collecting heat, and as a tracking type collector that effectively collects solar energy, it has a relatively small exclusive area. An object of the present invention is to provide a solar concentrator that can obtain a high heat collection ratio.

In order to achieve this object, a solar concentrator that collects and collects sunlight according to the present invention includes:
A parabolic main reflecting mirror that is mirror-finished so that the reflecting surface reflects the sunlight.
A heat collector integrated with the parabolic main reflecting mirror so as to be located in a focal region of the sunlight incident on the reflecting surface of the parabolic main reflecting mirror;
The incident direction of the sunlight to the reflecting surface of the parabolic main reflecting mirror is within a predetermined azimuth angle range and a predetermined elevation angle range in a state where the parabolic main reflecting mirror is integrated with the heat collector. With a mounting mechanism that supports the orientation adjustment,
When the incident direction to the reflecting surface of the parabolic main reflector is directed to the direction of sunlight on the mount mechanism, the sunlight is condensed on the heat collector and converted into thermal energy. It is configured to collect heat.

Moreover, the solar concentrator which collects and collects sunlight according to the present invention is
A parabolic main reflecting mirror that is mirror-finished so that the reflecting surface reflects the sunlight.
A reflecting surface of a hyperboloid or an elliptical surface that is mirror-finished to such a degree that it is specularly reflected with respect to the sunlight, the parabolic main reflecting mirror and the sunlight incident on the reflecting surface of the parabolic main reflecting mirror; A sub-reflector integrated with the parabolic main reflector so as to be in the middle of the top focus;
A heat collector integrated with the parabolic main reflector so as to be located in a focal region of the sunlight reflected from the reflecting surface of the sub-reflector;
The incident direction of the sunlight on the reflecting surface of the parabolic main reflecting mirror is set within a predetermined azimuth range with the parabolic main reflecting mirror integrated with the sub-reflecting mirror and the heat collector. And a mounting mechanism that supports the orientation adjustment within an elevation angle range of
When the incident direction to the reflecting surface of the parabolic main reflector is directed to the direction of sunlight on the mount mechanism, the sunlight is condensed on the heat collector and converted into thermal energy. It is configured to collect heat.

It can comprise so that the incident direction of the said sunlight to the said reflective surface of the said parabolic main reflector may be the principal axis direction of this parabolic main reflector.
Further, the incident direction of the sunlight to the reflecting surface of the parabolic main reflecting mirror can be configured to be a direction offset by a desired acute angle from the main axis direction of the parabolic main reflecting mirror.

  The mount mechanism includes a horizontal rotation support structure that is rotatable within the predetermined azimuth angle range, and an elevation rotation support structure that is rotatable within the predetermined elevation angle range on the horizontal rotation support structure. The horizontal rotation support structure and the elevation rotation support structure are individually controlled by an independent digital control signal obtained from orbit information by the ecliptic equation, and the incident direction to the reflection surface of the parabolic main reflector is the It can be configured to be directed in the direction of the sunlight on the mount mechanism.

The orbit information based on the solar ecliptic equation can be further configured such that the independent digital control signal is corrected by the corrected orbit information corrected by the time information.
The trajectory information by the solar ecliptic equation is further configured such that the independent digital control signal is corrected by the time information and the corrected trajectory information corrected by the position information where the solar collector is arranged. be able to.

  The solar collector / collector according to the present invention can obtain an equivalent energy density proportional to the gain of the collector / collector, and can effectively collect solar heat in a land area similar to the diameter of the parabolic collector reflector. It becomes possible to heat, and the vast land area which is a conventional Kushiro road becomes unnecessary. Further, since the heat transport path (transmission path) for the collected energy is also formed short, loss of the collected heat energy can be reduced and high system efficiency can be obtained.

Assuming that sunlight (heat) incident on an area of 1 m ² is condensed (heated) into an area of 10 cm ² using the parabolic heat collecting reflector, the energy density in the heat collection area is
1kw / m ² × 1m ² / (10 ^-3 ) m ² = 1000KW / m ² (1)
And rises in proportion to the area ratio. That is, assuming that the heat collection efficiency is 100%,
Heat collection ratio (condensing magnification) = sunlight incident area / heat collection light receiving area (2)
Only the energy density can be increased equivalently.

Here, the concept is the same as that of the parabolic antenna used in microwave communication. In particular, the heat collection ratio (condensation magnification) is hereinafter referred to as “heat collection gain”, and 1 kW / m ² is set as the reference value 1, It is expressed as a relative value as a heat ratio.

For example, if the heat collection ratio is 100, the heat collection gain is 100 times the relative gain with respect to the reference value 1, and the equivalent energy density is 100 KW / m ² .

In this Table 1, the dB value of the heat collection gain (relative value) is the heat collection gain (dB value) = ₁₀ log ₁₀ (heat collection ratio) (dBr) (3)
The degree of the physical meaning of the gain that contributes to the increase of the equivalent energy density can be shown.

FIG. 1A is a diagram showing an example of the basic configuration of a “pencil beam type” heat collecting reflector in which the present invention is implemented.
Reference numeral 1 denotes a parabolic main reflecting mirror that increases the reflection efficiency for directly reflecting direct incident sunlight (heat), and 3 denotes a conical heat collecting portion that is located at the focal point and has an increased heat absorption efficiency.
The approximate diameter of the main reflector 1 is relatively small, for example, several meters or less (1 to 3 m), and in combination with the heat collecting section 3, point condensing is performed to ensure various heat collecting gains and to correspond to the required thermal energy density It is a thing.

FIG. 1B is a basic configuration diagram of a “Cassegrain type” heat collecting reflector in which the present invention is implemented.
1 is a parabolic main reflector that directly reflects direct incident sunlight (heat) and has a high reflection efficiency, and 2 is a sub-reflector located between the parabolic main reflector 1 and its top focal point. Then, a heat collecting reflector system based on the principle of the Cassegrain telescope constituted by the heat collecting section 3 having a focal point at the central portion of the main reflector is formed again.

  In addition, as shown in FIGS. 1 c and 1 d, the heat collecting reflector used in the present invention has a desired incident direction of sunlight on the reflecting surface of the parabolic main reflecting mirror 1 from the main axis direction of the parabolic main reflecting mirror 1. It can be configured to be in a direction offset by an acute angle. In this case, since the main axis direction of the parabolic main reflector 1 is slightly offset from the direction of the sun, there is a slight energy loss, but the surface of the main reflector 1 is subtracted by the sub-reflector 2. Since it is not shielded against sunlight, there is a structural freedom. Further, the position of the heat collecting unit 3 can be freely arranged on the outer edge of the main reflecting mirror 1 or the like.

  The heat collecting part 3 of the present reflecting mirror is installed at a focal point located in the central part of the main reflecting mirror and can be focused outside the central part of the main reflecting mirror of the heat collecting reflecting mirror. Thus, it is possible to install a relatively large heat collecting section 3 that is free from the restriction of the heat collecting reflector that collects heat at the top.

  The approximate diameter of the main reflecting mirror 1 is relatively large, for example, several meters or more (2 to 6 m), and in combination with the heat collecting unit 3, heat collecting gains corresponding to various thermal energy densities can be obtained.

1 (a), (b), (c), and (d) are movable collections whose positions are controlled by an Az (Azimuth) axis and an E _L (Elevation) axis by a tracking type point condensing (thermal) method. It forms a heat reflecting mirror and has a high heat collecting gain in a relatively small area.

Next, the heat collection gain (heat collection ratio) of the parabolic heat collecting reflector according to the present invention will be specifically described with reference to the configuration model of FIG.
In the model of FIG.
-Heat collection gain (relative value): Gr (magnification) or (dBr value)
-Diameter of the main reflector: Dφ (m)
-Area of the main reflector: S _D (m ² ) = (π / 4) D ²
・ Diameter of collector: dφ (m)
-Area of the heat collector: Sd (m ² ) = (π / 4) d ²
-Heat collection efficiency: η (%)
・ Condensation area ratio: M = _SD / Sd
Reference energy density: Pr = 1 KW / m ²
・ Equivalent energy density: Pe (KW / m ² )
Gr = η · M = η · (S _D / Sd) = η · (D ² / d ² ) = η · (D / d) ²
Pe = Gr · Pr = Gr (KW / m ² )
That is, the heat collecting gain of the parabolic heat collecting reflector is expressed by multiplying the light collecting area ratio of the main reflecting mirror 1 and the heat collector 6 by the heat collecting efficiency.

The mirror surface of the main reflecting mirror 1 used in the present invention is a light-weighted frame structure made of a light metal having a curved paraboloid surface, such as an aluminum alloy or a synthetic resin, such as FRP, and reduced in weight by the metal or the synthetic resin. It is supported by.
The reflecting surface of the main reflecting mirror 1 is plated with, for example, nickel to improve the reflection efficiency of direct energy from the sun and mirror-reflect, and is provided at the top focal point. 3 or the sub-reflector 2 reflects sunlight (heat).

The mirror surface of the sub-reflecting mirror 2 is made of a light metal, such as an aluminum alloy, or a synthetic resin such as FRP, which is a curved surface of a rotating hyperboloid, based on the principle of the Cassegrain telescope.
Further, in order to improve the reflection efficiency of the energy reflected by the main reflecting mirror 1 and to give a mirror finish to the extent that it is specularly reflected, for example, it is plated with nickel or the like, and again at the focal position of the central portion of the main reflecting mirror 1. It is reflected to the heat collecting unit 3 to be installed.

Fixing portion 4 of the main reflector 1, a horizontal pivot (A _Z-axis) has a support structure, and a mechanism is supported by E _L axis undergoes an elevation angle rotation, the heat collecting dish overall body A _Z-axis -E It is a drive mechanism that drives and controls the solar energy capture to the optimum position by the _L- axis independent digital control signals.

FIG. 3 is a side view showing an example of the drive mechanism. The lower end of the fixed main column 32 is mounted on a mounting base (not shown) by using, for example, a stay bar, and the upper end thereof supports the horizontal base 33 horizontally. The turntable 34 is rotatably held on the upper surface of the horizontal pedestal 33. For this rotation, for example, a rack is provided on the periphery of the turntable 34, and a horizontal drive mechanism 40 including a gear (for example, a helical gear) that meshes with the rack is attached to the horizontal base 33. . A drive mechanism base 35 is mounted on the upper surface of the turntable 34. Reference numeral 31 denotes an annular support structure for supporting the parabolic main reflecting mirror 1, and is attached to the center of the back surface of the parabolic main reflecting mirror 1. A rotation shaft provided at the upper end of the support member 41 attached to the end of the drive mechanism base 35 in the coupling hole of the rotation support portion 36 provided at both ends of the diameter in the horizontal direction of the annular support structure 31. Is rotatably inserted.
Further, reference numeral 38 denotes an elevation angle adjusting rod, and a pin shaft attached to the upper end of the rod is rotatably coupled to a coupling hole of a rotational support portion 37 provided on the top of the annular support structure 31. The lower end portion of the elevation angle adjustment rod 38 is supported by an elevation angle adjustment drive mechanism 39 attached to the other end side of the drive mechanism base 35 so as to be freely driven.
With such a configuration, when the horizontal rotation mechanism 40 is electrically driven, for example, the turntable 34 can be horizontally rotated on the horizontal pedestal 33 by ± 90 °, and the parabolic main reflector 1 has the same ± 90 °. Is rotated horizontally. Further, for example, by driving the elevation angle adjustment drive mechanism 39 by hydraulic drive, the elevation angle adjustment rod 38 is driven so as to extend or shorten the length between the rotation support portion 37 and the elevation angle adjustment drive mechanism 39, and the parabolic main Since the annular support structure 31 of the reflecting mirror 1 rotates forward or backward about the rotation axis passing through the both rotation supporting portions 36 in the illustrated state, the parabolic main reflecting mirror 1 is also ± 45 °. It can be rotated in an elevation angle range. The elevation angle range is practically about 20 ° to 80 °, and tracking of the solar orbit is possible.
In the above configuration, the horizontal rotation drive mechanism 40 is controlled to rotate by a control motor or the like controlled by a control signal for horizontal rotation, and the elevation angle adjustment drive mechanism 39 is controlled by a control signal for elevation rotation. The solar trajectory can be automatically controlled by being controlled by a hydraulic control motor or the like.

  This drive mechanism is based on solar orbit information (equatorial equation) and 365-day time information, that is, seasonal information (spring, summer, autumn, winter), moon information (January / February ... December, etc.), sun Control driven by programmable position information by a control algorithm using information (sunrise, daytime, sunset, etc.) and 24-hour time information (hour, minute, second) as input conditions.

A heat collecting part 3 arranged at the top focal point of the main reflector 1 of the parabolic heat collecting antenna 1 that absorbs direct solar radiation energy from the sun, or a conical horn 5 and a heat collecting part arranged at the focal point of the sub-reflecting mirror 2. The device 6 is configured.
Since the conical horn 5 acts as a light guide (heat) for the reflected light (heat) from the main reflector or the sub-reflector, it is slightly caused by manufacturing errors and distortions of the main reflector 1 and the sub-reflector 2. It acts as an equalizer having a correction effect on the focal point disturbance, and efficiently collects and collects incident sunlight (heat) to the heat collector 6.

  The heat collector 6 is directly connected to a pipe through which liquid such as water or oil flows in and out, and is disposed at the output end of the conical horn 5 to absorb the concentrated (heated) solar energy. A black body heat collector with a structure that promotes turbulent absorption that promotes absorption by dimples or needles and a combination of them is installed in the circulator, and the heated liquid is circulated to the heat storage tank to store solar energy. To do.

  In the above description, the heat collecting unit 3 has been described as being disposed at the focal position of the main reflecting mirror 1, but the heat collecting unit 3 has an area wider than the theoretical focal point having an effective heat conversion function. Therefore, the same effect can be obtained even if the heat collecting part 3 is arranged in a range (referred to as a focal region) where the condensed sunlight is irradiated within this region.

The solar concentrator / heat collector according to the present invention captures and effectively uses the energy contained in the sunlight that reaches the ground surface. In the operation stage of the concentrated heat collection, the fossil fuel is used. Since there is no generation of substances harmful to the environment such as CO ₂ that is unavoidable when using the solar energy, the captured solar energy is transferred to the thermal storage tank without adversely affecting the natural environment, for example, It can be used by giving it to objects to be used such as electrical conversion.
The target of use in this case is heating of liquid or other objects such as water or oil in homes or small-scale establishments, or heat by heat storage such as Peltier effect element and Seebeac effect element. It can be effectively and widely used for small-scale energy conversion such as thermal power generation and air conditioning using electrical conversion.

The “pencil beam type” (a), the “cassegrain type” (b), the offset “pencil beam type” (c), and the offset “cassegrain type” (d) showing the embodiments of the present invention. It is a basic composition example figure. It is a model figure for demonstrating the heat collection gain (heat collection ratio) of the parabolic heat collection reflective mirror shown to Fig.1 (a), (b). It is a side view for demonstrating the example of an antenna support structure used for this invention. FIG. 4 is a perspective view showing a conventional fixed / non-condensing “flat plate” concentrator (a) and a fixed / condensing “flat plate” concentrator (b) using a plane mirror. 1 schematically illustrates a conventional tracking / point focusing “Fresnel lens” concentrator. FIG. 6 is a perspective view showing a conventional tracking / line focusing “cylindrical parabolic mirror type” concentrator. FIG. 6 is a perspective view showing a conventional tracking / point focusing “rotating paraboloidal mirror” concentrator.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Parabola main reflecting mirror 2 Sub reflecting mirror 3 Heat collecting part 4 Fixed part 5 Conical horn 6 Heat collector 7 Flat panel 8 Heat collecting plate 9 Fluid pipe line 10 Heat collecting tube 11 Glass plate 12 Heat insulating material 13 Flat mirror 14 Fresnel lens 15 Heat collector 16 Reflector (Cylindrical parabolic mirror)
17 Heat collection tube 18 Glass cylinder 19 Fluid inlet 20 Fluid outlet 21 Reflector (rotating paraboloid type)
DESCRIPTION OF SYMBOLS 31 Annular support structure 32 Fixed main pillar 33 Horizontal base 34 Turntable 35 Drive mechanism base 36 Rotation support part 37 Rotation support part 38 Elevation angle adjustment rod 39 Elevation angle adjustment drive mechanism 40 Horizontal rotation drive mechanism 41 Support member

Claims (7)

A solar concentrator that collects and collects sunlight,
A parabolic main reflecting mirror that is mirror-finished so that the reflecting surface reflects the sunlight.
A heat collector integrated with the parabolic main reflecting mirror so as to be located in a focal region of the sunlight incident on the reflecting surface of the parabolic main reflecting mirror;
The incident direction of the sunlight to the reflecting surface of the parabolic main reflecting mirror is within a predetermined azimuth angle range and a predetermined elevation angle range in a state where the parabolic main reflecting mirror is integrated with the heat collector. With a mounting mechanism that supports the orientation adjustment,
When the incident direction to the reflecting surface of the parabolic main reflector is directed to the direction of sunlight on the mount mechanism, the sunlight is condensed on the heat collector and converted into thermal energy. A solar concentrator that is configured to collect heat. A solar concentrator that collects and collects sunlight,
A parabolic main reflecting mirror that is mirror-finished so that the reflecting surface reflects the sunlight.
A reflecting surface of a hyperboloid or an elliptical surface that is mirror-finished to such a degree that it is specularly reflected with respect to the sunlight, the parabolic main reflecting mirror and the sunlight incident on the reflecting surface of the parabolic main reflecting mirror; A sub-reflector integrated with the parabolic main reflector so as to be in the middle of the top focus;
A heat collector integrated with the parabolic main reflector so as to be located in a focal region of the sunlight reflected from the reflecting surface of the sub-reflector;
The incident direction of the sunlight on the reflecting surface of the parabolic main reflecting mirror is set within a predetermined azimuth range with the parabolic main reflecting mirror integrated with the sub-reflecting mirror and the heat collector. And a mounting mechanism that supports the orientation adjustment within an elevation angle range of
When the incident direction to the reflecting surface of the parabolic main reflector is directed to the direction of sunlight on the mount mechanism, the sunlight is condensed on the heat collector and converted into thermal energy. A solar concentrator that is configured to collect heat.   The solar concentrator according to claim 1 or 2, wherein an incident direction of the sunlight to the reflecting surface of the parabolic main reflecting mirror is a main axis direction of the parabolic main reflecting mirror.   The incident direction of the sunlight to the reflecting surface of the parabolic main reflecting mirror is a direction that is offset by a desired acute angle from the main axis direction of the parabolic main reflecting mirror. Solar concentrator.   The mount mechanism includes a horizontal rotation support structure that is rotatable within the predetermined azimuth angle range, and an elevation rotation support structure that is rotatable within the predetermined elevation angle range on the horizontal rotation support structure. The horizontal rotation support structure and the elevation rotation support structure are individually controlled by an independent digital control signal obtained from orbit information by the ecliptic equation, and the incident direction to the reflection surface of the parabolic main reflector is the The solar concentrator according to any one of claims 1 to 4, wherein the solar collector is configured to be directed toward the sunlight on a mount mechanism.   6. The solar collection according to claim 5, wherein the orbit information by the solar ecliptic equation is further configured such that the independent digital control signal is corrected by the corrected orbit information corrected by time information. Light collector.   The trajectory information by the solar ecliptic equation is further configured such that the independent digital control signal is corrected by time information and corrected trajectory information corrected by position information where the solar collector is arranged. The solar concentrator according to claim 5, wherein

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