U.S. patent application number 13/001244 was filed with the patent office on 2011-04-28 for method and apparatus for correcting heliostat.
Invention is credited to Makoto Kounosu.
Application Number | 20110094499 13/001244 |
Document ID | / |
Family ID | 41444386 |
Filed Date | 2011-04-28 |
United States Patent
Application |
20110094499 |
Kind Code |
A1 |
Kounosu; Makoto |
April 28, 2011 |
METHOD AND APPARATUS FOR CORRECTING HELIOSTAT
Abstract
Provided are an adjusting method and an adjusting apparatus for
adjusting a heliostat on site while actually measuring that a
mirror surface of the heliostat and a mirror surface of a center
reflector are exactly facing each other. The adjusting apparatus is
provided with an irradiation device 3 which irradiates an upper
focal point p of a center reflector 30 and a heliostat 20 with
laser beams L1 and L2, respectively. The elevation angle and/or the
turning angle of the heliostat 20 are adjusted so that the
reflected light L4 of the laser beam applied on the heliostat 20
forms the same axial line as the laser beam L1 applied on the upper
focal point p of the center reflector 30.
Inventors: |
Kounosu; Makoto; (Tokyo,
JP) |
Family ID: |
41444386 |
Appl. No.: |
13/001244 |
Filed: |
June 11, 2009 |
PCT Filed: |
June 11, 2009 |
PCT NO: |
PCT/JP2009/060705 |
371 Date: |
December 23, 2010 |
Current U.S.
Class: |
126/601 ;
126/714 |
Current CPC
Class: |
F24S 23/79 20180501;
G01M 11/005 20130101; G02B 27/62 20130101; F24S 50/20 20180501;
F24S 2050/25 20180501; Y02E 10/47 20130101 |
Class at
Publication: |
126/601 ;
126/714 |
International
Class: |
F24J 2/40 20060101
F24J002/40; F24J 2/00 20060101 F24J002/00; F24J 2/38 20060101
F24J002/38 |
Foreign Application Data
Date |
Code |
Application Number |
Jun 27, 2008 |
JP |
2008-168878 |
Claims
1. A method for correcting a heliostat in a heat collecting device
including: a center reflector provided in an upper portion thereof;
a heat receiving part provided in a lower part thereof; and a
plurality of heliostats arranged around the center reflector, the
method for correcting a heliostat characterized by comprising the
steps of: providing an irradiation device irradiating an upper
focal point of the center reflector and the heliostat with laser
beams, respectively; and adjusting an elevation angle and/or a
turning angle of the heliostat so that a reflected light of the
laser beam applied on the heliostat forms a same axial line as the
laser beam applied on the upper focal point of the center
reflector.
2. An apparatus for correcting a heliostat in a heat collecting
device including: a center reflector provided in an upper portion
thereof; a heat receiving part provided in a lower part thereof;
and a plurality of heliostats arranged around the center reflector,
the apparatus for correcting a heliostat characterized by
comprising an irradiation device irradiating the center reflector
and the heliostat with laser beams, respectively, the irradiation
device being provided on a light path connecting an upper focal
point of the center reflector and the heliostat to each other.
3. The apparatus for correcting a heliostat according to claim 2,
characterized by comprising: a light receiving device detecting a
reflection laser beam reflected from the heliostat, the light
receiving device being provided in the vicinity of the laser
irradiation device side-by-side therewith; and an adjusting device
which turns and elevates the irradiation device and the light
receiving device.
4. The apparatus for correcting a heliostat according to claim 2,
characterized in that the laser irradiation device is attached to
and detached from the correcting apparatus by attachment and
detachment means, and is driven by a storage battery.
5. The apparatus for correcting a heliostat according to claim 2,
characterized in that the laser irradiation device irradiates the
upper focal point of the center reflector with a laser beam having
a wavelength in a range of 500 nanometers to 590 nanometers.
6. The apparatus for correcting a heliostat according to claim 3,
characterized in that the light receiving device is a sun tracking
device.
Description
TECHNICAL FIELD
[0001] The present invention relates to a heat collecting device
which collects solar heat by means of multiple heliostats, and more
particularly relates to a method and an apparatus for correcting a
heliostat which reflects solar heat.
BACKGROUND ART
[0002] Recently, due to soaring prices of fossil fuels and for the
protection of global environment, research and development on clean
energy not derived from fossil fuels have been actively carried
out. As such clean energy, power generation utilizing wind power or
solar heat has been started to be implemented.
[0003] In particular, much attention has been paid to a solar
thermal power generation system in which a heat medium is heated by
collecting solar heat so as to generate steam with the heat medium
as a thermal source for driving a steam turbine, thereby generating
electricity. This is because the solar thermal power generation
system is capable of being operated using a power generation
facility similar to that for conventional thermal power generation
while being capable of achieving high output.
[0004] As such a solar thermal power generation system capable of
achieving high output, a solar thermal power tower system and a
beam-down system for solar thermal power generation have been known
(refer to the Patent Document 1 and the Non-patent Document 1, for
example).
[0005] In the solar thermal power tower system described above,
multiple heliostats having planar reflecting mirrors are arranged
around a tower having a heater made of a heat medium provided in an
upper part thereof, and the multiple planar reflecting mirrors are
adjusted so that solar heat can be concentrated into the
heater.
[0006] In the beam-down system for solar thermal power generation
described above, multiple heliostats having planar reflecting
mirrors are arranged around a tower having a hemispherical center
reflector provided in an upper part thereof, and a heater made of a
heating medium provided below the reflector plate to collect solar
heat reflected from the multiple reflecting mirrors.
[0007] Further, each heliostat is provided with a tracking device
sensing the movement of the sun, and is controlled so as to
irradiate the heater or the center reflector with solar heat.
[0008] Meanwhile, the adjustment of the heliostat described above
has been carried out as follows: first, an orientation angle and an
elevation angle are roughly adjusted on the basis of calculated
values obtained from numerical values specified in design drawings,
and then the orientation angle and the elevation angle are further
adjusted on the basis of calculated values obtained from numerical
values derived from measurement of the actually-used heliostat.
PRIOR ART DOCUMENT
Patent Document
[0009] Patent Document 1: Japanese patent application Kokai
publication No. 2005-106432
[0010] Non-Patent Document
[0011] Non-patent Document 1: Solar Energy, Volume 62, Number 2,
February 1998, pp. 121-129(9)
SUMMARY OF THE INVENTION
Problems to be Solved by the Invention
[0012] In the case of the solar thermal power tower system and the
beam-down system for solar thermal power generation described
above, a variation and/or a deviation in a direction of the solar
heat irradiation occur due to measurement errors, since the
orientation angle and the elevation angle of the heliostat are
adjusted on the basis of the calculated values derived from design
drawings and of measurement as described above.
[0013] In this regard, it may also seem plausible that multiple
workers track the sunlight position while looking in a telescope
for the purpose of improving the adjustment accuracy of the
orientation angle and the elevation angle of a heliostat. However,
such an operation is not practical as the checking has to be
carried out whenever the heliostat is adjusted, thus involving a
large amount of time, effort, and labor costs.
[0014] Furthermore, solar thermal power tower systems and beam-down
systems for solar thermal power generation are built in desert
areas and the like in Middle Eastern countries and the like, where
the difference in temperature between day and night is large and
the solar thermal power tower systems and the beam-down systems for
solar thermal power generation are exposed to gale force wind.
Therefore, there has been a problem that large mirror plates
(facets) disposed on the heliostat are dislocated. That is, there
has been a problem that the heat collecting efficiency gradually
decreases from the time when the power generation systems are first
installed.
[0015] Focusing on such problems having arisen in the past, the
present invention has an object to provide a correcting method and
a correcting apparatus, the method and the apparatus being capable
of adjusting a heliostat on site while actually measuring that an
optical axis of facets disposed on the heliostat and an optical
axis of an upper focus of the center reflector are in
alignment.
Means for Solving the Problems
[0016] A method for correcting a heliostat according to the present
invention is configured as follows so as to achieve the
above-described object.
[0017] 1) The method for correcting a heliostat, in a heat
collecting device including: a center reflector provided in an
upper portion thereof; a heat receiving part provided in a lower
part thereof; and a plurality of heliostats arranged around the
center reflector, is characterized by comprising the steps of:
providing an irradiation device irradiating an upper focal point of
the center reflector and the heliostat with laser beams,
respectively; and adjusting an elevation angle and/or a turning
angle of the heliostat so that a reflected light of the laser beam
applied on the heliostat forms a same axial line as the laser beam
applied on the upper focal point of the center reflector.
[0018] An apparatus for correcting a heliostat according to the
present invention is configured as follows.
[0019] 2) The apparatus for correcting a heliostat, in a heat
collecting device including: a center reflector provided in an
upper portion thereof; a heat receiving part provided in a lower
part thereof; and a plurality of heliostats arranged around the
center reflector, is characterized by comprising an irradiation
device irradiating the center reflector and the heliostat with
laser beams, respectively, the irradiation device being provided on
a light path connecting an upper focal point of the center
reflector and the heliostat to each other.
[0020] 3) The apparatus for correcting a heliostat is characterized
by comprising: a light receiving device detecting a reflection
laser beam reflected from the heliostat, the light receiving device
being provided in the vicinity of the laser irradiation device
side-by-side therewith; and an adjusting device which turns and
elevates the irradiation device and the light receiving device.
[0021] 4) The apparatus for correcting a heliostat is characterized
in that the laser irradiation device is attached to and detached
from the correcting apparatus by attachment and detachment means,
and is driven by a storage battery.
[0022] 5) The apparatus for correcting a heliostat is characterized
in that the laser irradiation device irradiates the upper focal
point of the center reflector with a laser beam having a wavelength
in a range of 500 nanometers to 590 nanometers.
[0023] 6) The apparatus for correcting a heliostat is characterized
in that the light receiving device is a sun tracking device.
Effects of the Invention
[0024] The irradiation device which irradiates an upper focal point
of the center reflector and the heliostat with laser beams,
respectively, is provided. The elevation angle and/or the turning
angle of the heliostat is adjusted so that a reflected light of the
laser beam applied on the heliostat forms the same axial line with
the laser beam applied on the upper focal point of the center
reflector. Therefore, correction at an extremely high accuracy can
be achieved in comparison with adjusting methods based on
measurement and adjusting methods in which workers carry out
adjustment by looking in a telescope.
[0025] Further, since the laser irradiation device can be attached
and detached, multiple heliostats can be corrected sequentially
with the single irradiation device. Therefore, installation costs
of the irradiation device can be reduced.
[0026] Furthermore, since the correction operation can be carried
out even by one person, the efficiency can be improved
significantly compared to an adjustment operation carried out by
multiple persons upon spending time and effort.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] FIG. 1 is a schematic configuration diagram of a solar
thermal power generation system.
[0028] FIG. 2 is a schematic configuration diagram of a correcting
apparatus according to the present invention.
[0029] FIG. 3 is a schematic drawing of a laser irradiation
device.
[0030] FIG. 4 is a drawing showing a method for correcting a
heliostat using the correcting apparatus according to the present
invention.
[0031] FIG. 5A shows the relation between movement of a facet
disposed on the heliostat and the correcting apparatus during
correction.
[0032] FIG. 5B shows the relation between movement of the facet
disposed on the heliostat and the correcting apparatus after
completion of the correction.
BEST MODES FOR CARRYING OUT THE INVENTION
[0033] Hereinafter, an embodiment of the present invention will be
described on the basis of the attached drawings.
[0034] FIG. 1 is a schematic configuration diagram of a solar
thermal power generation system A in which a correcting apparatus
according to the present invention is used. As shown in FIG. 1, the
solar thermal power generation system A is provided with a
disc-shaped center reflector 30 supported on an upper part of a
supporting column 31 and a heliostat 20 arranged around the center
reflector 30. Beneath the center reflector 30, a receiver 33 which
collects solar heat is provided. A power generation system (not
shown in the drawing), such as a steam turbine using molten salt
heated by the receiver 33 as a thermal source, is also
provided.
[0035] The heliostat 20 described above has multiple facets 21
arranged therein in three rows, and the facets are linked together
via a link 24A of an elevating device 24 so that the elevation
angles of the respective facets can be adjusted. Also, the turning
angle of the heliostat 20 can be adjusted with a turning device
25.
[0036] Next, a correcting apparatus according to the present
invention will be described.
[0037] As shown in FIG. 2, a correcting apparatus 1 includes: an
irradiation device 2 on which laser oscillators 2A and 2B are
formed in such a manner as to respectively extend linearly from
both sides of a flange-shaped attachment 2F, and a light receiving
device 3 which is disposed in the vicinity of the irradiation
device 2 to detect a reflected light L4 of a laser beam. Further,
the irradiation device 2 and a light receiving device 3 are fixed
to a fixing plate 4 so that respective axial lines can be parallel
to each other.
[0038] The fixing plate 4 is pivoted on two arm parts 8 erected on
a bed plate 8D, and can be fixed at a specific elevation angle by
placing a positioning bolt 8A through a circular bolt hole.
Further, the bed plate 8D is fixed to a plate-shaped base part 6
with a bolt 6A, and a bolt hole for the bolt 6A also has a circular
shape so that the bed plate 8D can be fixed rotatably. In addition,
the bed plate 8D can be subjected to fine adjustment with a
slow-motion stage 9 provided below the base part 6.
[0039] Furthermore, a horizontal adjusting device 13 and a vertical
adjusting device 12 are provided. A member, such as a micrometer
head, which is capable of carrying out fine adjustment is used for
these adjusting devices.
[0040] As shown in FIG. 3, the irradiation device 2 is provided
with the laser oscillators 2A and 2B respectively provided on both
sides of a flange-shaped attachment 2F so that laser beams L1 and
L2 respectively irradiated from the laser oscillators 2A and 2B can
come on a same axial line. A side surface of the attachment part 2F
is formed on a reference plane f so that the irradiation device 2
can be parallel to the light receiver 3 when attached to the fixing
plate 4.
[0041] Further, the light receiver 3 serves as a sun tracking
sensor. When normal power generation is carried out, the turning
device 25 and the elevating device 24 of the heliostat 20 are
controlled so that a reflected light r2 from the heliostat 20 can
be the maximum value.
[0042] Next, a correcting method for the heliostat 20 using the
correcting apparatus 1 thus configured will be described.
[0043] FIG. 4 is a schematic drawing showing a state in which the
heliostat 20 is being corrected by adjusting the orientation angle
and the elevation angle of the facet 21 disposed on the heliostat
20.
[0044] The correcting apparatus 1 according to the present
invention is arranged on a light path c connecting the center
reflector 30 and the heliostat 20 to each other, and is disposed in
the vicinity of the facet 21 disposed on the heliostat 20.
[0045] The correcting apparatus 1 is provided in the vicinity of
the facet 21. This is because the low height of the light path c at
the position from ground ensures a stable operation to be carried
out on a work table as small as a trolley. Further, the correcting
apparatus 1 is provided in such a position because the position is
suitable to adjust the elevation angle and the orientation angle of
the heliostat 20.
[0046] For correction of the heliostat 20, first, the irradiation
device 2 is fixed to the fixing plate 4, to which the light
receiver 3 serving as a sun tacking device is fixed, to obtain the
correcting apparatus 1. Next, the laser beam L1 is irradiated from
the correcting apparatus 1 toward an upper focal point p of the
center reflector 30.
[0047] Since the distance between the upper focal point p and the
heliostat 20 varies in a range of tens of meters to hundreds of
meters depending on the scale of the solar thermal power generation
system, a laser beam having a wavelength which is easily visually
recognizable even from far is used as the laser beam L1 being
irradiated.
[0048] The wavelength of the beam light is preferably in a range of
500 nanometers to 590 nanometers. In the present embodiment, a
green light having a wavelength in the vicinity of 555 nanometers
(532 nanometers), which human eyes can perceive most strongly, is
used as an example. This enables easy visual observation to check
whether the laser beam L1 is applied on the upper focal point
p.
[0049] If the irradiation position is dislocated, the irradiation
position is adjusted by operating the slow-motion stage 9, the
elevation adjusting knob 12, or the like. By this operation, a
dislocation of the light receiver 3 serving as a sun tracking
device can be corrected.
[0050] Then, as shown in FIG. 5A and FIG. 5B, the elevating device
24 and the turning device 25 of the heliostat 20 are adjusted so
that the reflected light L4, which is a reflected light of the
laser beam L2 applied on the facets 21 disposed on the heliostat
20, can enter the light receiver 3. By this operation, so-called
origin alignment of the heliostat 20 is completed; therefore, the
direction of the facet 21 is corrected.
[0051] As described above, the sun tracking sensor (the light
receiving device 3) and the facet 21 can be corrected on site while
carrying out actual measurement. Thus, correction at an extremely
high accuracy can be achieved in comparison with correction carried
out on the basis of workers' sense based on visual observation and
of measurement.
[0052] Also, since the laser irradiation device 2 can be attached
and detached, multiple heliostats 20 can be adjusted sequentially
with the single irradiation device 2. Therefore, installation costs
of the irradiation device 2 can be reduced.
[0053] Furthermore, since the correction operation can be carried
out even by one person, the efficiency can be improved
significantly compared to the case where adjustment is carried out
by multiple persons on the basis of their sense upon spending
time.
[0054] Incidentally, the solar thermal power generation system in
the present embodiment is a beam-down system for solar thermal
power generation. However, the correcting apparatus according to
the present invention may be applied to a solar thermal power tower
system as well.
[0055] In other words, the correcting apparatus according to the
present invention may be used for any other system than a solar
thermal power generation system as far as such a system is
configured to collect solar heat into a predetermined position by
means of reflecting mirrors of multiple heliostats or the like.
EXPLANATION OF REFERENCE NUMERALS
[0056] A solar thermal power generation system
[0057] 1 correcting apparatus
[0058] 2 laser irradiation device
[0059] 3 light receiving device
[0060] 20 heliostat
[0061] 21 facet
[0062] 24 elevating device
[0063] 25 turning device
[0064] 30 center reflector
[0065] 33 receiver (heat receiving part)
[0066] c light path
[0067] p upper focal point
[0068] L1, L2 irradiated laser beams
[0069] L4 reflected light of laser beam
* * * * *