JP2011220286A - Solar thermal power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar thermal power generation system continuously operated without being affected by a reduction in the amount of solar radiation.SOLUTION: This solar thermal power generation system includes: a heliostat 12 reflecting solar light S; a heat receiver 116 receiving heat by incidence of the solar light S reflected by the heliostat 12; a plurality of gas turbines 122 each having a compressor 121 compressing air and supplying the compressed air to the heat receiver 116 and a turbine 114 rotatively driven by being supplied with the air received by the heat receiver 116; a generator 115 driven by the turbine 114 to generate electricity; an actinometer acquiring information on the amount of solar radiation of the solar light S; and a control means determining the number of gas turbines to be driven in order to reduce the number thereof in association with the reduction in the amount of solar radiation based on the amount of solar radiation acquired by the actinometer, and selectively driving the plurality of gas turbines 122.

Description

  The present invention relates to a solar thermal power generation system that generates electric power by heating a working fluid with the heat of sunlight and rotationally driving a turbine with the heated working fluid.

  In recent years, from the viewpoint of preventing global warming and suppressing the use of fossil fuels, power generation using clean energy that is obtained from natural phenomena and emits less harmful substances such as carbon dioxide and nitrogen carbide has attracted attention. However, power generation using clean energy is not sufficiently widespread because it has low conversion efficiency into power and high power generation costs. Among them, power generation by solar thermal energy having relatively high conversion efficiency to electric power is expected (for example, see Patent Document 1).

  By the way, a solar thermal power generation system that generates power using solar thermal energy includes a condensing device that reflects and collects sunlight, a heat receiver that heats the working fluid with heat received from sunlight, and a turbine that uses the heated working fluid. The gas turbine is usually composed of a rotating gas turbine and a generator driven by the gas turbine. The solar power generation system is generally classified into two types, a trough condensing method and a tower condensing method, according to the condensing device and the heat receiver.

  Here, the trough condensing method constitutes a condensing device as a semi-cylindrical mirror (trough), and constitutes a heat receiver as a pipe passing through the center of the cylinder, and heats the working fluid flowing in the pipe It is. However, in this trough condensing method, although the direction of the mirror is controlled so as to track sunlight, the control is uniaxial control. Therefore, since sunlight cannot be collected on the pipe with high accuracy, sufficient heating of the working fluid cannot be expected.

  On the other hand, in the tower condensing method, a heat receiver is arranged on the top of a tower erected on the ground, while a plurality of mirrors called heliostats are arranged as a light concentrator so as to surround the tower, and the heat receiver This is a system for heating the working fluid flowing through the. According to this tower condensing method, sunlight can be collected in the heat receiver with high accuracy by fine operation control of the heliostat, so that the working fluid can be heated to a higher temperature. Therefore, from the viewpoint of further increasing the efficiency of the power generation cycle, development of a solar thermal power generation system using this tower condensing method has been actively performed in recent years (for example, see Patent Document 1).

International Publication No. 2006/025449

  However, according to the conventional solar thermal power generation system using the tower condensing method, there is a problem that when the amount of solar radiation decreases, the operation of the gas turbine, which is one of the components, cannot be continued. FIG. 11 is a diagram showing the characteristics of the turbine constituting the gas turbine, in which the horizontal axis represents the solar radiation amount and the vertical axis represents the turbine output. The turbine has a characteristic that its output decreases as the amount of solar radiation decreases, and when the amount of solar radiation decreases to 40 to 50% or less of the design value, the output cannot be obtained and the operation cannot be continued. However, the conventional solar thermal power generation system has only one gas turbine, and the turbine is designed on the assumption that all the thermal energy received from sunlight is supplied to one gas turbine. Therefore, the solar radiation amount is easily reduced to 40 to 50% or less of the design value of the turbine, and since there is no output from the turbine as described above, there is a problem that the operation of the solar thermal power generation system cannot be continued. .

  The present invention has been made in view of such circumstances, and an object of the present invention is to provide a solar thermal power generation system capable of continuous operation in a wider area with respect to a decrease in the amount of solar radiation.

  In order to achieve the above object, the present invention employs the following means. That is, the solar thermal power generation system according to the present invention includes a heliostat that reflects sunlight, a heat receiver that receives sunlight and receives heat reflected by the heliostat, and compresses the working fluid and supplies the compressed heat fluid to the heat receiver. Acquire information on the compressor, a plurality of gas turbines having a turbine that is rotated by being supplied with the working fluid received by the heat receiver, a generator that is driven by the turbine to generate electric power, and the amount of solar radiation. And determining the number of units to be driven so as to decrease as the amount of solar radiation decreases based on the amount of solar radiation acquired by the solar radiation amount information acquiring means And a control means for driving.

  According to such a configuration, a plurality of gas turbines are provided, and the turbines are designed on the assumption that the thermal energy received from sunlight is divided and supplied to the plurality of gas turbines. The design value of the amount of solar radiation received is set low. And when the amount of solar radiation decreases, the number of gas turbines driven by the control means decreases, so even if the amount of solar radiation decreases to 40 to 50%, the amount of solar radiation is less than that of the turbine when viewed from the driven gas turbine. It does not decrease to 40 to 50% of the design value. Thereby, even if the solar radiation amount decreases, the operation of the solar thermal power generation system can be continued in a wider area.

  In addition, the solar thermal power generation system according to the present invention includes a plurality of the heliostats, a plurality of the heat receivers corresponding to the gas turbine, and the control means is provided in the heat receiver corresponding to the gas turbine to be driven. The direction of the heliostat is controlled so that sunlight selectively enters.

  According to such a configuration, each gas turbine is provided with a heat receiver, and a solar thermal power generation system can be configured by combining a plurality of the same configurations. Therefore, the system design is easy, and the number of gas turbines is reduced. Easy to adjust arbitrarily.

  In addition, the solar thermal power generation system according to the present invention includes switching means that can select a plurality or one of each discharge pipe connected from the heat receiver to the turbine of each gas turbine, and the control means is driven by the switching means. The exhaust pipe corresponding to the gas turbine to be selectively circulated is characterized.

  According to such a configuration, the heat receiver is shared by the plurality of gas turbines, and the gas turbine that supplies the working fluid is selected by the switching unit. Thereby, since the heat receiver and the tower which arrange | positions this heat receiver may be one, size reduction as the whole solar thermal power generation system can be achieved. Moreover, since the reflected light of a heliostat should just be collected on a fixed heat receiver, the direction control of a heliostat becomes simple.

  According to the solar thermal power generation system according to the present invention, even when the amount of solar radiation is reduced to 40 to 50%, the amount of solar radiation is reduced to 40 to 50% or less of the design value of the turbine when viewed from the driven gas turbine. There is nothing. Therefore, even if the amount of solar radiation decreases, the operation of the solar thermal power generation system can be continued in a wider area.

The schematic diagram which shows the structure of the solar thermal power generation system which concerns on 1st Embodiment of this invention. The A direction arrow directional view which looked at the tower located in the center in FIG. 1 from A direction. The schematic longitudinal cross-sectional view which shows the internal structure of a tower main body. FIG. 4 is a schematic perspective view showing the configuration of the heat receiver. The schematic side view which shows the structure of a heliostat. Explanatory drawing for demonstrating operation | movement of the solar thermal power generation system 10 in case there are many solar radiation amounts of sunlight S. FIG. Explanatory drawing for demonstrating operation | movement of the solar thermal power generation system 10 in case the solar radiation amount of sunlight S is small. Explanatory drawing for demonstrating operation | movement of the solar thermal power generation system 10 in case the solar radiation amount of sunlight S is medium. The graph which showed the relationship between the solar radiation amount and the number of the gas turbines to drive, and the relationship between the solar radiation amount and the output of each turbine. The schematic diagram which shows the internal structure of the tower main body which comprises a tower about the solar thermal power generation system which concerns on 2nd Embodiment of this invention. The figure which shows the characteristic of the turbine which comprises the conventional solar thermal power generation system.

  Embodiments of the present invention will be described below with reference to the drawings. First, the configuration of the solar thermal power generation system according to the first embodiment of the present invention will be described. FIG. 1 is a schematic plan view showing the overall configuration of the solar thermal power generation system 10 according to the first embodiment. 2 is a view in the direction of arrow A in which the tower 11B located at the center in FIG. 1 is viewed from the A direction. The solar thermal power generation system 10 employs a tower condensing method as its condensing method, and the three towers 11A, 11B, 11C installed on the ground G and the front of each tower 11A, 11B, 11C on the ground G A plurality of heliostats 12 installed on the side, a solarimeter (solar radiation amount information acquisition means) 13 installed on the ground G, and each part of the towers 11A, 11B, and 11C based on information acquired from the solarimeter 13 And control means 14 for controlling the operation of the installed equipment and the operation of each heliostat 12. Note that the number of towers 11A, 11B, and 11C is not limited to three, and any number of towers 11A, 11B, and 11C can be installed as long as they are more than one.

  The towers 11 </ b> A, 11 </ b> B, and 11 </ b> C accommodate each component of the solar thermal power generation system 10 excluding the heliostat 12. Each of the towers 11 </ b> A, 11 </ b> B, and 11 </ b> C includes a support leg 111 erected on the ground G and a tower main body 112 provided on the top of the support leg 111. And the sunlight S reflected by each heliostat 12 injects into the inside from the bottom part of the tower main body 112. As shown in FIG.

  FIG. 3 is a schematic longitudinal sectional view showing the internal configuration of the tower main body 112. The tower main body 112 includes a housing 113 that is a hollow box-shaped member, a gas turbine 114 that is accommodated in an upper portion of the housing 113, and a generator 115 that is also provided on the upper portion of the housing 113 adjacent to the gas turbine 114. And a heat receiver 116 disposed in the lower part of the housing 113.

  As shown in FIG. 3, the housing 113 has an internal cavity that is vertically divided into two by a partition wall 113A. An upper storage chamber 117 is formed above the partition wall 113A, and a lower storage chamber 118 is formed below the partition wall 113A. In addition, a sunlight incident hole 119 for allowing sunlight S reflected by the heliostat 12 to enter is provided at the bottom of the housing 113. Furthermore, an air introduction hole 120 for taking in air (working fluid) to be supplied to the gas turbine 114 from the outside into the upper housing chamber 117 is formed on the side surface of the housing 113. The air introduction hole 120 is also used for exhausting the exhaust gas of the gas turbine 114 from the upper housing chamber 117 to the outside as necessary. The working fluid is not limited to the air of the present embodiment, and any gas can be used.

  The housing 113 includes a temperature sensor that detects heat received by the heat receiver 116, an auxiliary drive device that starts the gas turbine 114, and air and gas turbine before being heated by the heat receiver 116, as necessary. A regenerative heat exchanger that exchanges heat with the exhaust of 114, an auxiliary combustor that auxiliaryly burns air and flows into the gas turbine 114, and a silencer that cancels vibration of the generator 115 are arranged. Also good. In this way, the equipment installation area can be reduced by arranging and arranging various devices inside the tower body 112.

  As shown in FIG. 3, the gas turbine 114 is arranged at the end on the same side as the air introduction hole 120 and the compressor 121 arranged at the end opposite to the air introduction hole 120 in the upper accommodation chamber 117. A turbine 122. The compressor 121 generates compressed air by sucking and compressing the air in the upper housing chamber 117. Although not shown in detail in FIG. 3, one end of a connection pipe 133 extending from a heat receiver 116 described later is connected to the compressor 121. On the other hand, the turbine 122 is rotationally driven by being supplied with air as a working fluid. As shown in FIG. 3, one end of a discharge pipe 126 extending from the heat receiver 116 is connected to the turbine 122.

  The generator 115 converts kinetic energy generated by the rotation of the turbine 122 constituting the gas turbine 114 into electric energy, and takes it out as electric power. As shown in FIG. 3, the generator 115 is disposed at a position facing the air introduction hole 120 in the upper accommodation chamber 117.

  The configuration in which the generator 115 converts the kinetic energy of the turbine 122 into electric energy is not limited to the configuration in which the generator 115 is directly driven by the rotation of the turbine 122 as in the present embodiment, but the rotation of the turbine 122 is also performed. It also includes a configuration in which the generator 115 is indirectly driven by the above. For example, although details are not shown in the figure, steam may be generated by heating water with the exhaust gas of the turbine 122, and the generator 115 may be driven by rotating the steam turbine with the steam.

  The heat receiver 116 is for heating the compressed air generated by the compressor 121 with the heat of sunlight S. FIG. 4 is a schematic perspective view showing the configuration of the heat receiver 116 and shows a partially broken state. The heat receiver 116 includes a casing 123, a heat receiving pipe 124 accommodated inside the casing 123, a supply pipe 125 passing through the bottom of the casing 123 and having one end connected to the heat receiving pipe 124, and a top portion of the casing 123. And a discharge pipe 126 having one end connected to the heat receiving pipe 124.

  The inside of the casing 123 is sealed, and as shown by a broken line in FIG. 4, a sunlight introduction hole 127 for introducing sunlight S reflected by the heliostat 12 is formed at the bottom. The sunlight introduction hole 127 is formed in a substantially circular shape in plan view, and the diameter thereof is a size that takes into consideration the spot diameter of the sunlight S, that is, the minimum value of the diameter at the time of condensing. Although details are not shown in FIG. 4, the inner wall surface of the casing 123 is covered with a heat insulating material that absorbs the heat of the sunlight S. As a result, the inside of the casing 123 is insulated from the outside, and the back side of the heat receiving pipe 124, that is, the side not facing the sunlight introduction hole 127 is heated by the heat radiated from the heat insulating material. Note that the shape of the casing 123 can be appropriately changed according to the size and shape of the heat receiving pipe 124 accommodated therein.

  By the way, in FIG. 4, the position of the sunlight introduction hole 128 formed in the casing 123 is shown by a one-dot chain line in the tower 11A located at the left end among the three towers 11A, 11B, and 11C shown in FIG. Yes. The sunlight introduction hole 128 is formed on the right side, that is, on the central tower 11B side as compared with the sunlight introduction hole 127 indicated by a broken line in FIG. As shown in FIG. 1, the leftmost tower 11A has a larger number of heliostats 12 on the right side than the left side, so that more light coming from the right side can be received. is there. On the other hand, in FIG. 4, the position of the sunlight introduction hole 129 formed in the casing 123 is shown by a two-dotted line with respect to the tower 11C located at the right end among the three towers 11A, 11B, and 11C shown in FIG. ing. The sunlight introduction hole 129 is formed from the left side, that is, the central tower 11B side as compared with the sunlight introduction hole 127 shown by a broken line in FIG. As shown in FIG. 1, the tower 11C at the right end has a larger number of heliostats 12 on the left side than the right side, so that it can receive more light from the left side. is there. Note that the leftmost tower 11A and the rightmost tower 11C differ from the central tower 11B only in the positions of the sunlight introduction holes 128 and 129, and the other configurations are the same, so the description thereof is omitted here. .

  As shown in FIG. 4, the heat receiving pipes 124 are arranged in parallel to each other and extend in the vertical direction, and a plurality of heat receiving thin pipes 130 and upper header pipes 131 that connect the upper ends of the heat receiving thin pipes 130 and extend in the horizontal direction. And a lower header tube 132 that is connected to the lower end of each heat receiving thin tube 130 and extends in the horizontal direction. The heat receiving thin tube 130 receives the sunlight S and heats the compressed air flowing inside with the heat of the sunlight S. As shown in FIG. 4, the heat receiving thin tube 130 is provided at a position where the sunlight S introduced from the sunlight introduction hole 127 can be received in consideration of the positional relationship between the sunlight introduction hole 127 and the heliostat 12. Yes. Further, the upper header pipe 131 and the lower header pipe 132 make the temperature uniform by combining the air flowing through the heat receiving thin tubes 130. In addition, the shape of the heat receiving thin tube 130, the upper header tube 131, and the lower header tube 132 constituting the heat receiving tube 124 is not limited to this embodiment, and can be appropriately changed in design.

  The supply pipe 125 supplies air to the heat receiving pipe 124. As shown in FIG. 4, one end of the supply pipe 125 is connected to the lower header pipe 132, penetrates the casing 123, and branches into two branches. And as shown in FIG. 3, the connection piping 133 is connected to the branch end part of this supply piping 125, respectively. Although not shown in detail in FIG. 3, the connection pipe 133 passes through the partition wall 113 </ b> A of the housing 113, is drawn into the upper housing chamber 117, and is connected to the compressor 121. Thereby, the compressor 121 and the heat receiving pipe 124 are connected via the supply pipe 125 and the connection pipe 133. On the other hand, the exhaust pipe 126 exhausts air from the heat receiving pipe 124. As shown in FIG. 4, one end of the discharge pipe 126 is connected to the upper header pipe 131, passes through the casing 123, and further passes through the partition wall 113 </ b> A and is drawn into the upper storage chamber 117. It is connected. Thereby, the turbine 122 and the heat receiving pipe 124 are connected via the discharge pipe 126.

  As shown in FIG. 3, the heat receiver 116 configured as described above is housed in the lower housing chamber 118 of the housing 113, and the casing 123 is suspended and supported by the hanger 134 attached to the partition wall 113 </ b> A. As described above, the heat receiver 116 is not brought into contact with the wall surface of the housing 113, thereby preventing the heat of the heat receiver 116 from escaping to the housing 113.

  According to the towers 11A, 11B, and 11C configured as described above, the sunlight S reflected and collected by each heliostat 12 shown in FIG. 2 passes through the sunlight incident hole 119 shown in FIG. Incident inside. The sunlight S is introduced into the casing 123 from the sunlight introduction hole 127 and is received by the heat receiving thin tubes 130, the upper header tube 131, and the lower header tube 132 constituting the heat receiving tube 124. Thereby, the heat receiving pipe 124 is heated by the heat of the sunlight S.

  On the other hand, the compressor 121 shown in FIG. 3 generates compressed air and sends it to the connecting pipe 133. Then, the compressed air flows from the connection pipe 133 through the supply pipe 125 to the lower header pipe 132, branches from the lower header pipe 132, and flows into the heat receiving thin tubes 130. Then, the compressed air flows through the heat receiving thin tubes 130 from the bottom to the top and merges by flowing into the upper header tubes 131 from the heat receiving thin tubes 130. 122. Thereby, the turbine 122 is rotationally driven by the compressed air, and the generator 115 driven by the rotation of the turbine 122 generates electric power. Here, while the compressed air flows through the lower header tube 132, each heat receiving thin tube 130, and the upper header tube 131 accommodated in the casing 123, its temperature rises by being heated by the heat of sunlight S. .

  The heliostat 12 reflects the sunlight S and collects it at the position of the sunlight incident hole 119 of the housing 113. Here, FIG. 5 is a schematic side view showing the configuration of the heliostat 12. The heliostat 12 is provided with a base 135 for fixing to the ground G, a rotation mechanism 136 that extends vertically from the base 135 and is rotatable about an axis, and is tiltable on the top of the rotation mechanism 136. A tilting mechanism 137 and a reflecting mirror 138 supported by the tilting mechanism 137. According to the heliostat 12 configured as described above, the sunlight S is reflected by the reflecting mirror 138, and can be reflected in an arbitrary direction. According to such a configuration, the reflecting mechanism 138 can be directed in a desired direction by appropriately rotating the rotating mechanism 136 around the axis and tilting the tilting mechanism 137 by an arbitrary angle. Thereby, the sunlight S reflected by the reflecting mirror 138 can be condensed at a desired position regardless of the position of the sun.

  The solar radiation meter 13 measures the solar radiation amount of sunlight S. As shown in FIG. 2, the pyranometer 13 is electrically connected to the control unit 14, and the measurement result is input to the control unit 14. In addition, in this embodiment, the solar radiation amount of the sunlight S irradiated to the ground G was measured with the solar radiation meter 13 as information regarding the solar radiation amount of sunlight S. However, the information on the amount of solar radiation is not limited to the amount of solar radiation itself, and other information can be adopted as long as the information shows a similar increase / decrease tendency as the amount of solar radiation increases / decreases. For example, instead of the amount of solar radiation on the ground G, the amount of solar radiation reflected by the heliostat 12, the amount of heat received by the heat receiving pipe 124, the temperature of the air at the inlet portion of the turbine 122, the air at the outlet portion of the turbine 122 Information such as the temperature of the turbine, the output of the turbine 122, and the like. Weather information and date / time information can also be used as other information relating to the amount of solar radiation.

  As shown in FIGS. 2 and 3, the control means 14 is electrically connected to the pyranometer 13, each heliostat 12, the compressor 121, and the turbine 122, and a measurement result input from the pyranometer 13. The operation of each heliostat 12, the compressor 121, and the turbine 122 is controlled based on the above. In addition, you may control the operation | movement of the other structural member which comprises the solar thermal power generation system 10 by the control means 14. FIG.

  Next, the operation control of the solar thermal power generation system 10 according to the first embodiment and the effects thereof will be described. 6-8 is explanatory drawing for demonstrating the difference in operation | movement of the solar thermal power generation system 10 by the difference in the solar radiation amount of sunlight S. FIG. First, FIG. 6 is a diagram for explaining the operation of the solar thermal power generation system 10 when the amount of solar radiation is large, that is, when the amount of solar radiation measured by the pyranometer 13 is larger than a predetermined first threshold. ) Is a schematic view of the solar thermal power generation system 10 as viewed from the side, and FIG. 6B is a schematic view of the solar thermal power generation system 10 as viewed from above. In the present embodiment, the first threshold value of the solar radiation amount is set to about 2/3 of the design value of the turbine 122, but the magnitude of the first threshold value can be changed as appropriate.

  In this case, the control means 14 shown in FIG. 1 drives all of the gas turbine 114 of the tower 11A, the gas turbine 114 of the tower 11B, and the gas turbine 114 of the tower 11C. Further, as shown in FIG. 6 (b), the control means 14 is configured so that each of the heliostats receives sunlight S so that all of the heat receiver 116 of the tower 11A, the heat receiver 116 of the tower 11B, and the heat receiver 116C of the tower 11C receive light S. Each of the 12 directions is controlled. 5B, FIG. 6B, and FIG. 7B, the heliostat 12 labeled “A” indicates that the reflected light is received by the heat receiver 116 of the tower 11A. The heliostat 12 labeled "" receives its reflected light by the heat receiver 116 of the tower 11B, and the heliostat 12 labeled "C" receives its reflected light by the heat receiver 116 of the tower 11C. Respectively.

  Further, the control means 14 controls the orientation of each heliostat 12 so that all the heat receivers 116 receive the sunlight S as described above, and, as shown in FIG. Three types of heliostat 12 received by the heat receiver 116 of 11A, heliostat 12 received by the heat receiver 116 of the tower 11B, and heliostat 12 received by the heat receiver 116 of the tower 11C are on the ground G. The direction of each heliostat 12 is controlled so as to be evenly distributed. As a result, each heat receiver 116 receives sunlight S from various angles, so that not only a part of the heat receiving tube 124 but also the entire heat receiving tube 124 can receive the sunlight S. Therefore, since the compressed air passing through the inside of all the heat receiving pipes 124 is heated, the power generation efficiency can be improved.

  In this way, by driving all the gas turbines 114 to generate electric power, all of the heat received from the sunlight S can be taken out as electric power, and the amount of solar radiation received by each turbine 122 is a design value. Therefore, the operation can be continued stably.

  Next, FIG. 7 is a diagram for explaining the operation of the solar thermal power generation system 10 when the amount of solar radiation is small, that is, when the amount of solar radiation measured by the pyranometer 13 is smaller than a predetermined second threshold. FIG. 7A is a schematic view of the solar thermal power generation system 10 viewed from the side, and FIG. 7B is a schematic view of the solar thermal power generation system 10 viewed from above. In the present embodiment, the second threshold value of the solar radiation amount is set to about １ ／ of the design value of the turbine 122, but the magnitude of the second threshold value can be changed as appropriate.

  In this case, the control means 14 shown in FIG. 1 drives only the gas turbine 114 shown in FIG. 7A and stops the remaining two gas turbines 114. Further, as shown in FIG. 7B, the control means 14 controls the direction of each heliostat 12 so that the reflected light of all the heliostats 12 is received by the heat receiver 116 of the tower 11B.

  In this way, since all of the received solar radiation amount is received only by the heat receiver 116 and only the gas turbine 114 of the tower 11B is driven to generate power, the turbine 122 constituting the gas turbine 114 can be used even when the solar radiation amount is small. The probability that the amount of solar radiation received is reduced to 40 to 50% or less of the design value for one gas turbine is reduced. Therefore, an output is continuously obtained from the turbine 122 of the tower 11B, and the solar thermal power generation system 10 can be stably operated. In the present embodiment, only the gas turbine 114 of the tower 11B is driven, but instead, only the gas turbine 114 of the tower 11A or only the gas turbine 114 of the tower 11C may be driven.

  Next, FIG. 8 is a diagram for explaining the operation of the solar thermal power generation system 10 when the amount of solar radiation is medium, that is, when the amount of solar radiation measured by the solar radiation meter 13 is larger than the second threshold and smaller than the first threshold. FIG. 8A is a schematic view of the solar thermal power generation system 10 as viewed from the side, and FIG. 8B is a schematic view of the solar thermal power generation system 10 as viewed from above.

  In this case, the control means 14 shown in FIG. 1 drives the gas turbine 114 of the tower 11B and the tower 11C shown in FIG. 8A, and stops the gas turbine 114 of the tower 11A. Furthermore, the control means 14 controls the direction of each heliostat 12 so that the heat receiver 116 of the tower 11B and the tower C receives sunlight S, as shown in FIG.8 (b). At this time, as shown in FIG. 8 (b), the control means 14 has a total of 2 heliostats 12 received by the heat receiver 116 of the tower 11B and heliostats 12 received by the heat receiver 116 of the tower 11C. The direction of each heliostat 12 is controlled so that the types are evenly distributed on the ground G. As a result, each heat receiver 116 receives sunlight S from various angles, so that not only a part of the heat receiving tube 124 but also the entire heat receiving tube 124 can receive the sunlight S. Thereby, since the compressed air which passes through the inside in all the heat receiving pipes 124 is heated, the power generation efficiency can be increased.

  In this way, the received solar radiation amount is received by the heat receivers 116 of the tower 11B and the tower 11C, and the gas turbine 114 of the tower 11B and the tower 11C is driven to generate power. Therefore, even if the solar radiation amount is medium, the gas turbine The amount of solar radiation received by the turbine 122 constituting 114 is unlikely to drop to 40 to 50% or less of the design value for two gas turbines. Therefore, output is continuously obtained from the turbines 122 of the tower 11B and the tower 11C, and the solar thermal power generation system 10 can be stably operated. In this embodiment, the gas turbines 114 of the tower 11B and the tower 11C are driven. Instead, the gas turbines 114 of the tower 11A and the tower 11B or the gas turbines 114 of the tower 11A and the tower 11C are driven. May be. In the present embodiment, two gas turbines 114 are selected and driven from the three gas turbines 114. However, depending on the total number of gas turbines 114, three or more gas turbines 114 are selected and driven. It is also possible.

  Here, FIG. 9 is a graph showing the relationship between the amount of solar radiation and the number of gas turbines 114 to be driven, and the relationship between the amount of solar radiation and the output of each turbine 122. In FIG. 9, the horizontal axis indicates the amount of solar radiation, and the vertical axis indicates the number of gas turbines 114 to be driven and the output of each turbine 122. As described above, when the amount of solar radiation is large, all three gas turbines 114 are driven. At this time, as the amount of solar radiation decreases, the output of each turbine 122 gradually decreases. And if the amount of solar radiation falls to a predetermined value, the number of drive of the gas turbine 114 will be reduced to two. At this time, since the amount of solar radiation received by each gas turbine 114 increases, the output of each turbine 122 temporarily increases. However, when the amount of solar radiation further decreases, the output of each turbine 122 begins to decrease again. When the amount of solar radiation is further reduced to a predetermined value, the number of driven gas turbines 114 is reduced to one. As described above, a plurality of gas turbines 114 having a small design value of the solar radiation amount are installed, and the number of gas turbines 114 to be driven is decreased as the solar radiation amount is decreased. Accordingly, since the gas turbine 114 having a small design value of the solar radiation amount is used, even if the solar radiation amount is reduced to 40 to 50% or less of the design value of one gas turbine 114, the output is continuously output from the turbine 122. Is obtained.

  Next, the structure of the solar thermal power generation system which concerns on 2nd Embodiment of this invention is demonstrated. As compared with the first embodiment, the solar thermal power generation system of the second embodiment is provided with only one tower, and a plurality of gas turbines and one heat receiver are accommodated in the one tower. Is different. Since the other configuration is the same as that of the first embodiment, the same reference numerals are used and description thereof is omitted.

  FIG. 10 is a schematic diagram showing the internal structure of the tower main body 211 constituting the tower 21. The tower main body 211 includes a housing 212 that is a hollow box-shaped member, three gas turbines 213, 214, and 215 accommodated in the upper portion of the housing 212, and each gas turbine 213, 214, Three generators 216, 217, and 218 provided adjacent to 215, and one heat receiver 219 disposed at the lower portion of the housing 212. A supply pipe 220 extending from the lower header pipe 219a of the heat receiver 219 is branched and connected to the compressors 221, 222, and 223 constituting the gas turbines 213, 214, and 215, respectively. Open / close valves 224, 225, and 226 capable of opening or closing 220 are provided. On the other hand, a discharge pipe 227 extending from the upper header pipe 219b of the heat receiver 219 is branched and connected to turbines 228, 229, and 230 constituting the gas turbines 213, 214, and 215, respectively. Open / close valves (switching means) 231, 232, 233 that can be opened or closed are provided.

  According to such a configuration, the open / close valves 224, 225, 226 of the supply pipe 220 and the open / close valves 228, 229, 230 of the discharge pipe 227 are appropriately opened / closed to receive heat from any of the compressors 221, 222, 223. Compressed air can be supplied to the vessel 219, and compressed air heated by the heat receiver 219 can be discharged to any turbine 228, 229, 230. Thereby, when the solar radiation amount of sunlight S is large, three gas turbines 213, 214, and 215 are driven, and as the solar radiation amount decreases, the number of gas turbines 213, 214, and 215 to be driven is reduced to two. Can be reduced with a table. In addition, the effect of reducing the drive number of the gas turbines 213, 214, and 215 with the decrease in the amount of solar radiation is the same as that of 1st Embodiment.

  According to the solar thermal power generation system of this embodiment, since the heat receiver 219 and the tower 21 that accommodates the heat receiver 219 may be one, the overall solar thermal power generation system can be reduced in size. Further, since the reflected light of the heliostat 12 may be collected in one heat receiver 219, the direction control of the heliostat 12 is simplified.

  The various shapes, combinations, operation procedures, and the like of the constituent members shown in the above-described embodiments are merely examples, and various changes can be made based on design requirements and the like without departing from the gist of the present invention.

10 ... Solar thermal power generation system 12 ... Heliostat 13 ... Solar radiation meter (irradiance information acquisition means)
14 ... Control means 114 ... Turbine 115 ... Generator 116 ... Heat receiver 121 ... Compressor 122 ... Gas turbine 231, 232, 233 ... Open / close valve (switching means)
S ... Sunlight

Claims (3)

A heliostat that reflects sunlight,
A heat receiver that receives sunlight and receives heat reflected by the heliostat;
A plurality of gas turbines including a compressor that compresses the working fluid and supplies the compressor to the heat receiver, and a turbine that is rotated by being supplied with the working fluid received by the heat receiver;
A generator driven by the turbine to generate electricity;
Solar radiation information acquisition means for acquiring information related to solar radiation,
Control means for selectively driving a plurality of the gas turbines based on the amount of solar radiation acquired by the solar radiation amount information acquisition means, determining the number of units to be driven to decrease as the amount of solar radiation decreases.
A solar thermal power generation system comprising: In the solar thermal power generation system of Claim 1,
With a plurality of the heliostats,
A plurality of the heat receivers corresponding to the gas turbine,
The said control means controls the direction of the said heliostat so that sunlight may selectively inject into the said heat receiver corresponding to the said gas turbine to drive, The solar thermal power generation system characterized by the above-mentioned. In the solar thermal power generation system of Claim 1,
Switching means capable of selecting a plurality of or one of each exhaust pipe connected to the turbine of each gas turbine from the heat receiver,
The control means causes the switching means to selectively distribute the exhaust pipe corresponding to the gas turbine to be driven.

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