Solar disc-type condensation system with low wind load and damping vibration attenuation

Abstract

The invention discloses a low-wind-load and damping vibration attenuation solar disc-type condensation system which comprises a condenser, a double-shaft tracking device, a main beam, a liquid amount adjusting system, a plurality of steel cables and the like. The condenser is composed of a steel framework, a plurality of mirror surface units, a covering body, a plurality of liquid storage bags and the like, wherein the steel framework is composed of a plurality of radiation beams and cross rods which are arrayed circumferentially; the mirror surface units are fixed on the steel framework; the covering body wraps the steel framework on the back of the condenser to form a streamline aerodynamic shape so as to reduce wind load, and only the reflecting surface of the mirror surface unit bears wind pressure, so that the wind load is effectively reduced; the mirror surface unit adopts a light high-rigidity structure with a light supporting back frame and an embedded bearing framework, so that the deformation of a reflecting element under wind pressure is reduced; the double-shaft tracking device is installed on the back of the condenser and is close to a pneumatic center to reduce the wind moment load. The liquid level of the liquid storage bag and the liquid storage box which is installed on the main beam and can move is adjusted, self-adaptive liquid damping energy dissipation and vibration reduction of the light condensation system under the wind disturbance effect are achieved, and the service optical precision is improved.

Description

Technical Field

[0001] This invention belongs to the field of solar concentrated thermal power generation and new energy utilization, and in particular relates to a solar dish concentrator system with low wind load and damping vibration reduction. Background Technology

[0002] Solar dish concentrators typically use parabolic mirrors to concentrate low-density solar energy, providing a high-temperature heat source or high-density light energy to the receiver. They are widely used in high-temperature thermal power generation, photovoltaic power generation, and high-temperature hydrogen production, enabling the development and utilization of renewable solar energy. To improve solar energy utilization efficiency, output power, and reduce system costs, the light-collecting diameter of a single dish concentrator can typically reach 10.0–20.0 m, thus providing higher density light or heat energy. However, existing large dish concentrators have large windward areas and poor wind permeability. Wind loads directly affect their structural cost and operational optical performance. Wind load-induced concentrator structural deformation can cause optical errors or even mirror breakage, leading to a deterioration in the focused solar energy density distribution. This poses a serious challenge to their safe and efficient operation, especially for high-concentration photovoltaic systems or Stirling thermal power generation / high-temperature hydrogen production systems with high requirements for focused energy distribution. Therefore, reducing wind loads and structural vibrations under dynamic wind conditions is crucial for improving the cost-effectiveness of dish concentrators.

[0003] In the prior art (e.g., Chinese patent applications 201220209967.7 and 201410288615.9), a typical dish-type concentrator system usually includes a concentrator, a support truss fixedly connected at one end to a central fixed body of the concentrator, a support column fixed to the foundation, and a height-azimuth dual-axis tracking device installed on the top of the support column. The concentrator includes several radiating beams fixed in a circular array along the central fixed body, connecting rods connecting adjacent radiating beams, and several mirror units installed on the radiating beams and connecting rods. The height-azimuth dual-axis tracking device includes an azimuth rotation device connected to the top of the support column, and a movable support column installed at the other end of the azimuth rotation device and arranged coaxially. The top of the movable support column is hinged to the support truss by a pin, and the two ends are respectively hinged to the lower side of the movable support column and the support truss by pins, thereby forming a triangular pitch mechanism to drive the change of the concentrator's elevation angle. The Stirling thermal power generation unit, used for the conversion of thermal energy to mechanical energy to electrical energy, is installed at the other end of the supporting truss and at the focal point of the concentrator's reflector. The shortcomings of existing technology are: as a spatial blunt-body structure, the dish concentrator system experiences wind pressure loads on the front and rear surfaces of each reflector unit when wind acts from any direction. These loads often combine to form a larger resultant wind pressure force, leading to significant elastic deformation or damage to the reflector units, directly affecting the optical accuracy and lifespan of the concentrator. Furthermore, the steel truss structure (steel frame) at the back of the concentrator results in a poor aerodynamic shape (open structure), making it difficult to effectively reduce the aerodynamic load on the entire concentrator. This leads to high stiffness requirements for the steel truss, dual-axis tracking device, columns, and other structures, increasing construction costs. Existing structural designs focus more on structural strength and static deformation, but the concentrator system has low structural damping, resulting in significant vibration under pulsating wind loads, which significantly affects concentrating performance. Summary of the Invention

[0004] This invention provides a solar dish concentrator system with low wind load and damping vibration reduction. Wind load is reduced by creating a streamlined aerodynamic shape through a cover that completely encloses the steel structure at the back of the concentrator. Furthermore, only the reflective surface of the mirror unit bears the wind pressure load, further reducing the wind load on the mirror unit. The mirror unit employs a lightweight, high-rigidity structure with a lightweight support frame and an embedded load-bearing skeleton, minimizing deformation of the reflective elements under wind pressure loads. Aerodynamic torque load is reduced by installing a dual-axis tracking device on the back of the concentrator, close to the aerodynamic center. Liquid damping and vibration reduction under wind disturbance are achieved by incorporating several elastic liquid storage bags on the cover and movable liquid storage tanks mounted on the main beam.

[0005] The technical solution adopted in this invention is: a low wind load and damping vibration reduction solar dish concentrator system, comprising a concentrator for concentrating solar energy, a support column with its axis perpendicular to the ground plane and fixed to the foundation, a dual-axis tracking device installed on the top of the support column for realizing the pitch and azimuth rotation of the concentrator, several fixed rods fixed to the concentrator and extending along its focal direction, a fixed seat with flanges fixed to the extended ends of each fixed rod, and a heat absorber fixed to the flanges of the fixed seat and absorbing the solar energy concentrated by the concentrator; it also includes a main beam of a space truss structure, a liquid volume adjustment system, and several steel cables; the concentrator includes a connector with flanges at both ends, several planar truss structure radiation beams arranged in a circular array around the focal axis of the concentrator, and connecting... The system comprises several crossbars connecting the upper chords of adjacent radiating beams, several mirror units fixed above the upper chords and crossbars of each radiating beam to form a focusing optical functional surface, a cover for enclosing the radiating beams and crossbars, several elastic reservoir bags containing liquid damping medium placed on the cover, a pressure plate for fixing the cover, and several dampers placed between adjacent radiating beams. This connecting body is coaxial with the focal axis of the condenser, and its flanges at both ends are bolted to the flanges at the beginning of the upper and lower chords of each radiating beam. Each mirror unit consists of a lightweight supporting backplate, a frame-type load-bearing skeleton embedded within the supporting backplate, and a light-gathering reflective element. The upper surface of the supporting backplate is consistent with the geometric surface of the mirror unit within the optical functional surface. The reflective element is adhered to this upper surface to form an optical functional curved surface. The load-bearing frame has several screws extending from the back of the supporting back plate. The mirror unit is fixed to the radiating beam and crossbar via these screws. The covering body consists of several lightweight thin-shell or thin-film structures distributed circumferentially along the focal axis of the condenser and attached to the folded surface of the lower chord of the radiating beam. Each covering body is fixed to the lower chord of the radiating beam by a pressure plate, and the covering body wraps around the outermost mirror unit of the optical functional curved surface, achieving complete enclosure of the steel structure at the back of the condenser. The main beam includes a U-shaped truss beam with a rectangular cross-section and a fully open bottom, and flanges A and B located at both ends of the truss beam. The U-shaped opening faces the ground. Flange A is fixedly connected to the flange of the connecting body at the center of the condenser. The beam is located on the non-concentrating side of the concentrator; one end of the steel cable is fixed to the end of the radiating beam in the concentrator, and the other end is fixed to the flange B of the main beam; the dual-axis tracking device includes an azimuth tracking device fixed and coaxially connected to the flange at the top of the support column, a column C fixedly coaxially to the other moving end of the azimuth tracking device, a screw jack that drives the concentrator and the main beam to pitch together, bearing seat B, bearing seat A, and a support shaft fixed to the top of the column C; the rotation axis of the azimuth tracking device is perpendicular to the ground plane, and the axis of the support shaft is perpendicular to the rotation axis of the azimuth tracking device; the side wall of the column C is provided with a hinge, which is connected to the end of the telescopic screw of the screw jack by a pin, and the axis of the hinge is parallel to the axis of the support shaft.In the aforementioned screw jack, the base's rotating shaft is mounted on the upper chord of the main beam via bearing seats B. Two bearing seats B are coaxially arranged along the two upper chords of the main beam, and the axis of the bearing seats B is parallel to the axis of the hinge lug. Two bearing seats A are coaxially fixed on the two lower chords of the main beam, and the two journals of the support shaft are respectively installed in the two bearing seats A. The liquid volume adjustment system includes a liquid storage tank located on the upper chord of the main beam and capable of sliding and adjusting its position along the length of the upper chord; a pump and control system for adjusting the liquid level in the liquid storage tank and storage bag; and several solenoid valves, one end of which is connected to the pump and the other end of which are respectively connected to the storage bag.

[0006] In the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the liquid storage tank is a cubic or spherical cavity structure with a liquid storage rate of 30% to 50%. The liquid storage tank is fixed to the slide of a lead screw sliding platform for position adjustment, and the lead screw sliding platform is fixed to the upper chord of the main beam. The solenoid valve is a multi-way selector valve, allowing connection between the liquid storage tank and any one of the liquid storage bags and independent adjustment of their liquid storage rates. The pump is a bidirectional pump capable of bidirectionally pumping liquid between the liquid storage tank and the liquid storage bag. The liquid storage rate in the liquid storage bag is 20% to 40%.

[0007] Preferably, in the above-mentioned low wind load and damping vibration reduction solar dish concentrator system, the liquid medium contained in the storage bag is water, silicone oil, mineral oil, glycerin aqueous solution, or antifreeze liquid ethylene glycol aqueous solution.

[0008] Preferably, in the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the supporting column includes a column A with one end fixed to the foundation and having a conical structure with a smaller top and a larger bottom, and a column B coaxially fixed to the top end of column A; the orientation tracking device is a worm gear rotary disk, and the non-rotatable part of the orientation tracking device is coaxially fixed to the top end of column B by a flange.

[0009] Preferably, in the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the liquid storage bag fixed on the cover is rectangular and located in the middle of two adjacent radiating beams, near the outer edge of the concentrator where the vibration amplitude is greatest; the liquid storage bag is made of weather-resistant elastic plastic, such as silicone, thermoplastic polyurethane elastomer, PVC flexible leather, or EPDM rubber; the cover is made of waterproof, windproof, and weather-resistant canvas, PVC membrane, glass fiber composite material, PTFE membrane, or ETFE membrane.

[0010] Preferably, in the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the load-bearing frame is a frame structure made of high-strength carbon steel, high-strength aluminum alloy, or carbon fiber composite material, and the screws extending from the back of the supporting back plate are made of carbon steel; the reflective element is a high-reflectivity glass silver mirror, a reflective film, or a high-reflectivity nano-coating directly sprayed onto the surface of the load-bearing frame; the supporting back plate is a lightweight structure made of polyurethane, glass fiber, and high-strength adhesive, and its surface is coated with a weather-resistant and waterproof coating.

[0011] In the aforementioned low wind load and damping vibration reduction solar dish concentrator system, bearing seat A is closer to the flange A side of the main beam than bearing seat B. The main beam, screw jack, and column C constitute a planar pitching mechanism. The motor drives the screw jack to extend and retract, enabling the main beam and concentrator to pitch together. The focal axis of the concentrator is perpendicular to the rotation axis of the concentrator's pitching motion. The U-shaped opening of the main beam is larger than that of the supporting column and column C. When the concentrator pitches to the point where the focal axis points to the zenith, the supporting column and column C are housed within this U-shaped opening.

[0012] Preferably, in the above-mentioned low wind load and damping vibration reduction solar dish concentrator system, one end of the damper is ball-jointed to the end of the lower chord of the radiating beam, and the other end is ball-jointed to the center of the adjacent crossbar. Two dampers are provided between two adjacent radiating beams. The damper is a piston-type viscous damper or a friction damper.

[0013] In the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the aforementioned steel cables are symmetrically distributed around the focal axis of the concentrator, and one end of the steel cable is fixedly connected to the lower chord of the radiation beam in the concentrator; the aforementioned optical functional surface is a parabolic surface, spherical surface or free optical surface, and the entire optical functional surface is divided radially and circumferentially to obtain the optical surface shape of each mirror unit.

[0014] Preferably, in the aforementioned low wind load and damping vibration reduction solar dish concentrator system, the coordinates of the lower chord of the radiating beam that determines the aerodynamic shape of the cover are determined as follows: Projecting the radiating beam onto a two-dimensional plane with its end pointing to the right, establishing the origin at the vertex of the optical functional surface, using the vertically upward focal axis of the concentrator as the +y axis and the horizontally to the right as the +x axis, the coordinates of the six inflection points of the lower chord of the radiating beam used to determine the aerodynamic shape of the cover are as follows: Point P1 coordinates are [0.10×R, - ... The coordinates of point P2 are [0.24×R, -0.17×R], the coordinates of point P3 are [0.50×R, -0.12×R], the coordinates of point P4 are [0.74×R, -0.04×R], the coordinates of point P5 are [0.91×R, 0.06×R], and the coordinates of point P6 are [1.0×R, 0.21×R]. Here, R is the light-collecting radius of the optical functional surface of the concentrator. The broken line obtained by connecting these 6 points with straight lines is the aerodynamic shape of the cover. Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] (1) By using a lightweight and high-strength cover to completely wrap the steel structure on the back of the concentrator to form a streamlined aerodynamic shape, the wind load is reduced. The mirror unit only bears the wind pressure load on the reflective surface. The back of the mirror unit is in the space wrapped by the cover and is under normal pressure, which effectively reduces the wind load borne by the mirror unit.

[0016] (2) The mirror unit adopts a lightweight and high-rigidity structure with a lightweight support back frame and an embedded load-bearing frame. During service, the wind pressure load on the surface of the reflective element will be evenly transferred to the support back plate, and after passing through the load-bearing frame, it will be transferred to the radiation beam and crossbar by the connecting screw. This effectively reduces the deformation of the reflective element under the action of wind pressure load and improves the optical accuracy during service.

[0017] (3) By installing the dual-axis tracking device on the back of the concentrator, close to the aerodynamic center, the aerodynamic torque load is reduced, the service life and load deformation of the dual-axis tracking device are improved, thereby effectively improving the tracking accuracy under wind load.

[0018] (4) By adjusting the liquid levels of several liquid storage bags on the cover and the movable liquid storage tank installed on the main beam, the adaptive liquid damping energy dissipation and vibration reduction of the disc concentrator system under wind disturbance can be achieved, thereby improving the optical accuracy of the concentrator system during service. Moreover, the liquid storage tank is fixed on the slide of the screw sliding platform for position adjustment. The screw sliding platform is fixed on the upper chord of the main beam. Under windless conditions, the position of the liquid storage tank can be adjusted to achieve the gravity balance of the entire concentrator system, thereby reducing the gravitational torque load on the dual-axis tracking device. Attached Figure Description

[0019] Figure 1 This is a front view of the solar dish concentrator system of the present invention.

[0020] Figure 2 for Figure 1 A rear axonometric view of a solar dish concentrator system.

[0021] Figure 3 for Figure 1 A front axonometric view of a solar dish concentrator system.

[0022] Figure 4 This is an axonometric view of the mirror unit and cover of the concentrator hidden portion in the solar dish concentrator system of the present invention.

[0023] Figure 5 for Figure 4 Axial view of the back of the central condenser.

[0024] Figure 6 This is an axonometric view of the mirror unit in this invention.

[0025] Figure 7 This is a front view of the connection structure of the supporting column, dual-axis tracking device and main beam in this invention.

[0026] Figure 8 for Figure 7 Axonometric view of the structure.

[0027] Figure 9 This is the broken line of the lower chord of the radiation beam in the concentrator of the present invention, which determines the aerodynamic shape of the cover.

[0028] In the diagram: 1-Support column; 101-Column A; 102-Column B; 2-Dual-axis tracking device; 201-Orientation tracking device; 202-Column C; 2021-Hinge; 203-Screw jack; 204-Bearing housing B; 205-Bearing housing A; 206-Support shaft; 3-Main beam; 301-Flange B; 302-Flange A; 303-Truss beam; 3031-Upper chord; 3032-Lower chord ; 4-Liquid volume adjustment system; 401-Liquid storage tank; 402-Pump and control system; 5-Steel cable; 6-Fixing rod; 7-Fixing base; 8-Concentrator; 801-Cover; 802-Liquid storage bag; 803-Pressure plate; 804-Connector; 805-Radiation beam; 806-Crossbar; 807-Damper; 808-Mirror unit; 8081-Reflective element; 8082-Supporting back plate; 8083-Bearing frame. Detailed Implementation

[0029] The invention will now be further described with reference to the accompanying drawings.

[0030] like Figures 1-3As shown, a low wind load and damping vibration reduction solar dish concentrator system includes a concentrator 8 for concentrating solar energy, a support column 1 with its axis perpendicular to the ground plane and fixed to the foundation, a dual-axis tracking device 2 installed on the top of the support column 1 for realizing the pitch and azimuth rotation of the concentrator, several fixed rods 6 fixed to the concentrator 8 and extending along its focal direction, a fixing seat 7 with flanges fixed to the extended ends of each fixing rod 6, and a heat absorber fixed to the flange of the fixing seat 7 and absorbing the solar energy concentrated by the concentrator 8; it also includes a main beam 3 of a space truss structure, a liquid volume adjustment system 4, and several steel cables 5.

[0031] like Figures 4-5 As shown, the concentrator 8 includes a connector 804 with flanges at both ends, several planar truss-structured radiation beams 805 arranged in a circular array around the focal axis of the concentrator 8, several crossbars 806 connecting the upper chords of adjacent radiation beams 805, several mirror units 808 fixed above the upper chords and crossbars 806 of each radiation beam 805 and forming a focusing optical functional surface, a cover 801 for wrapping the radiation beams 805 and crossbars 806, several elastic liquid storage bags 802 containing liquid damping medium disposed on the cover 801, a pressure plate 803 for fixing the cover 801, and several dampers 807 disposed between adjacent radiation beams 805; the connector 804 is coaxial with the focal axis of the concentrator, and the flanges at both ends of the connector 804 are bolted to the flanges at the beginning of the upper and lower chords of each radiation beam 805. Figure 4 and Figure 6 As shown, the mirror unit 808 consists of a lightweight support back plate 8082, a frame-type load-bearing skeleton 8083 embedded inside the support back plate 8082, and a reflective element 8081 for light energy focusing. The upper surface of the support back plate 8082 is consistent with the geometric surface of the mirror unit 808 in the entire optical functional surface. The reflective element 8081 forms the optical functional surface by being adhered to this upper surface. The load-bearing skeleton 8083 is provided with several screws and extends from the back of the support back plate 8082. The mirror unit 808 is fixed to the radiation beam 805 and the crossbar 806 by these screws. During service, the wind pressure load on the surface of the reflective element will be evenly transferred to the support back plate 8082, and after passing through the load-bearing skeleton 8083, it will be transferred to the radiation beam 805 and the crossbar 806 by the connected screws, effectively reducing the deformation of the reflective element under the action of wind pressure load and improving the optical accuracy during service. The optical functional surface is a parabolic surface, a spherical surface, or a freeform optical surface. The entire optical functional surface is divided radially and circumferentially to obtain the optical surface shape of each mirror unit. For example... Figures 1-5As shown, the cover 801 is a number of lightweight thin shell or film structures distributed circumferentially along the focal axis of the concentrator 8 and attached to the folded surface of the lower chord of the radiation beam 805. Each cover 801 is fixed to the lower chord of the radiation beam 805 by a pressure plate 803. The cover 801 wraps around the outermost mirror unit 808 of the optical functional curved surface, thereby completely wrapping the steel structure at the back of the entire concentrator, thus forming a streamlined aerodynamic shape to reduce the wind load of the entire concentrator. Moreover, only the reflective surface of the mirror unit bears the wind pressure load, while the back of the mirror unit is in the space wrapped by the cover 801 and is in a normal pressure state, which effectively reduces the wind load of the mirror unit.

[0032] like Figure 2 , Figure 7 and Figure 8As shown, the main beam 3 includes a U-shaped truss beam 303 with a rectangular cross-section and a fully open bottom, flanges A 302 and B 301 located at both ends of the truss beam 303. The U-shaped opening faces the ground. Flange A 302 is fixedly connected to the flange of the connecting body 804 at the center of the concentrator 8. The main beam 3 is located on the non-concentrating side of the concentrator 8, i.e., the back of the concentrator 8. The several steel cables 5 are symmetrically distributed around the focal axis of the concentrator 8. One end of the steel cable 5 is fixedly connected to the lower chord of the radiation beam 805 in the concentrator 8, and the other end is fixed to the flange B 301 of the main beam 3. The addition of several steel cables 5 reduces the out-of-plane deformation and wind disturbance vibration of the concentrator, and improves the optical accuracy in service. The dual-axis tracking device 2 includes an azimuth tracking device 201 fixedly connected to the top flange of the supporting column 1 and coaxially, and a column C fixedly connected to the other moving end of the azimuth tracking device 201. 202, a screw jack 203 that drives the concentrator 8 and the main beam 3 to pitch together, bearing seats B204 and A205, and a support shaft 206 fixed to the top of the column C202; the rotation axis of the azimuth tracking device 201 is perpendicular to the ground plane, and the axis of the support shaft 206 is perpendicular to the rotation axis of the azimuth tracking device 201; the side wall of the column C202 is provided with a hinge 2021, which is pin connected to the end of the telescopic screw of the screw jack 203, and the axis of the hinge 2021 is parallel to the axis of the support shaft 206; the rotating shaft of the base of the screw jack 203 is installed on the upper chord 3031 of the main beam 3 through bearing seats B204, and the two bearing seats B204 are coaxially arranged along the two upper chords 3031 of the main beam 3, and the bearing seats B204 are fixed to the top of the column C202. The axis of 204 is parallel to the axis of the hinge 2021; a bearing seat A 205 is coaxially fixed on each of the two lower chords 3032 of the main beam 3, and the two journals of the support shaft 206 are respectively installed in the two bearing seats A 205; the aerodynamic center of the parabolic disc concentrator under wind load is usually located on the non-concentrating side of the concentrator. This invention installs the dual-axis tracking device on the back of the concentrator to effectively reduce the wind torque load, improve the service life and load deformation of the dual-axis tracking device, and effectively improve the tracking accuracy under wind load. The liquid level adjustment system 4 includes a liquid storage tank 401 located on the upper chord 3031 of the main beam 3 and capable of sliding and adjusting its position along the length of the upper chord; a pump and control system 402 for adjusting the liquid level of the medium in the liquid storage tank 401 and the liquid storage bag 802; and a number of solenoid valves connected at one end to the pump and at the other end to the liquid storage bag 802. The pump is connected to the liquid storage tank 401. By adjusting the liquid level of the several liquid storage bags 802 on the cover 801 and the movable liquid storage tank 401 installed on the main beam 3, the liquid damping energy dissipation and vibration reduction of the dish concentrator system under wind disturbance is achieved.

[0033] Preferably, the liquid storage tank 401 has a cubic or spherical cavity structure, and the liquid storage rate inside the cavity is 30%~50%, maximizing the damping energy dissipation effect of the liquid storage tank 401. The liquid storage tank 401 is fixed on the slide of the lead screw sliding platform for position adjustment. The lead screw sliding platform is fixed on the upper chord 3031 of the main beam 3. Under windless conditions, the position of the liquid storage tank 401 is adjusted to achieve the gravity balance of the entire focusing system, reducing the gravitational torque load on the dual-axis tracking device 2. The solenoid valve is a multi-way selection valve, which can select the liquid storage tank 401 to connect with any one of the liquid storage bags 802 and independently adjust the liquid storage rate of the liquid storage bag 802. The pump is a bidirectional pump that can pump liquid bidirectionally between the liquid storage tank 401 and the liquid storage bag 802. The liquid storage rate inside the liquid storage bag 802 is 20%~40%. Preferably, the liquid medium contained in the storage bag 802 is water, silicone oil, mineral oil, glycerol aqueous solution, or antifreeze liquid ethylene glycol aqueous solution.

[0034] like Figure 1 As shown, preferably, the supporting column 1 includes a column A 101 with one end fixed to the foundation and a conical structure with a smaller upper end and a larger lower end, and a column B 102 coaxially fixed to the upper top end of column A 101; the orientation tracking device 201 is a worm gear rotary disk, and the non-rotatable part of the orientation tracking device 201 is coaxially fixed to the top end of column B 102 by a flange.

[0035] like Figure 2 As shown, preferably, the liquid storage bag 802 fixed on the cover 801 is rectangular and located in the middle of two adjacent radiation beams 805, close to the outer edge of the concentrator 8 where the vibration amplitude is the greatest, so as to generate the greatest vibration energy dissipation effect; the liquid storage bag 802 is made of weather-resistant elastic plastic, such as silicone, thermoplastic polyurethane elastomer, polyvinyl chloride flexible leather or EPDM rubber; the cover 801 is made of waterproof, windproof and weather-resistant canvas, PVC membrane, glass fiber composite material, PTFE membrane or ETFE membrane, which has the advantages of being lightweight and high-strength.

[0036] like Figure 6 As shown, preferably, the load-bearing frame 8083 is a frame structure made of high-strength carbon steel, high-strength aluminum alloy or carbon fiber composite material, and the screws extending from the back of the support back plate 8082 are made of carbon steel; the reflective element 8081 is a high-reflectivity glass silver mirror, a reflective film or a high-reflectivity nano-coating directly sprayed onto the surface of the load-bearing frame 8083; the support back plate 8082 is a lightweight structure made of polyurethane, glass fiber and high-strength adhesive through a mold, and its surface is coated with a weather-resistant and waterproof coating.

[0037] like Figure 7 and Figure 8 As shown, preferably, the bearing housing A 205 is closer to the flange A side 302 of the main beam 3 than the bearing housing B 204. The main beam 3, the screw jack 203, and the column C 202 constitute a planar pitching mechanism. The motor drives the screw of the screw jack 203 to perform telescopic movement to achieve the common pitching movement of the main beam 3 and the concentrator 8. The focal axis of the concentrator 8 is perpendicular to the rotation axis of the concentrator's pitching movement. The U-shaped opening of the main beam 3 is larger than the supporting column 1 and column C 202. When the concentrator 8 pitches to the point where the focal axis points to the zenith, the supporting column 1 and column C 202 will be contained within this U-shaped opening, and no movement interference will occur.

[0038] like Figure 4 As shown, preferably, one end of the damper 807 is ball-jointed to the end of the lower chord of the radial beam 805, while the other end is ball-jointed to the center of the adjacent crossbar 806. Two dampers 807 are provided between two adjacent radial beams 805. The damper 807 is a piston-type viscous damper or a friction damper to achieve damping, energy dissipation, and vibration reduction under pulsating wind.

[0039] like Figure 9 As shown, preferably, the coordinates of the lower chord of the radial beam 805, which determines the aerodynamic shape of the cover 801, are determined as follows: Projecting the radial beam 805 onto a two-dimensional plane with its end pointing to the right, establishing the origin at the vertex of the optical functional surface, and using the upward-pointing optical focal axis of the condenser 8 as the +y axis and the horizontal-to-right direction as the +x axis, the coordinates of the six inflection points of the lower chord of the radial beam 805 used to determine the aerodynamic shape of the cover 801 are as follows: Point P1 coordinates are [0.10×R, -0.17]. The coordinates of point P2 are [0.24×R, -0.17×R], the coordinates of point P3 are [0.50×R, -0.12×R], the coordinates of point P4 are [0.74×R, -0.04×R], the coordinates of point P5 are [0.91×R, 0.06×R], and the coordinates of point P6 are [1.0×R, 0.21×R]. Here, R is the light-collecting radius of the optical functional surface of the concentrator 8. The broken line obtained by connecting these 6 points with straight lines is the aerodynamic shape of the cover 801. Taking a large parabolic dish concentrator system with a concentrator radius of R=8.85 m as an example, the CFD numerical simulation method was used to obtain the numerical comparison of drag, lift and lateral force of the dish concentrator of the present invention and the existing dish concentrator (with the back steel structure exposed to the outside) as shown in Table 1. The wind speed was set to 17.1 m / s, and the wind condition with the most severe wind load of the dish concentrator at a height angle of 0° was given. It can be seen that the dish concentrator of the present invention can reduce the wind load under various wind conditions, especially when the wind direction angle is 90°~180° (at which time the back of the concentrator faces the wind), the load reduction effect is significant.

[0040]

Claims

1. A low-wind-load and damping-reducing solar dish concentrator system, comprising a concentrator for concentrating solar energy, a support column with its axis perpendicular to the ground plane and fixed to the foundation, a dual-axis tracking device installed at the top of the support column for realizing the pitch and azimuth rotation of the concentrator, a plurality of fixed rods fixed to the concentrator and extending along its focal direction, a mounting base with flanges fixed to the extended ends of each mounting rod, and a heat absorber fixed to the flange of the mounting base and absorbing the solar energy concentrated by the concentrator; characterized in that, It also includes a main beam of a space truss structure, a liquid volume regulation system, and several steel cables; the concentrator includes a connector with flanges at both ends, several planar truss structure radiation beams arranged in a circular array around the concentrator focal axis, several crossbars connecting the upper chords of adjacent radiation beams, several mirror units fixed above the upper chords and crossbars of each radiation beam and forming a focusing optical functional surface, a cover for wrapping the radiation beams and crossbars, several elastic liquid storage bags containing liquid damping medium set on the cover, pressure plates for fixing the cover, and several dampers set between adjacent radiation beams; the connector is coaxial with the concentrator focal axis, and the flanges at both ends are connected to the flanges at the beginning of the upper and lower chords of each radiation beam. Bolt-fixed connections are made; the mirror unit consists of a lightweight supporting back plate, a frame-type load-bearing skeleton embedded inside the supporting back plate, and a light-gathering reflective element. The upper surface of the supporting back plate coincides with the geometric surface of the mirror unit in the optical functional surface. The reflective element is adhered to this upper surface to form the optical functional surface. The load-bearing skeleton is provided with several screws that extend from the back of the supporting back plate, and the mirror unit is fixed to the radiation beam and crossbar by these screws. The cover is a number of lightweight thin shell or film structures distributed circumferentially along the focal axis of the condenser and attached to the folded surface of the lower chord of the radiation beam. Each cover is fixed to the lower chord of the radiation beam by a pressure plate, and the cover wraps around the outermost part of the optical functional surface. The mirror unit at the edge completely encloses the steel structure at the back of the concentrator; the main beam includes a U-shaped truss beam with a rectangular cross-section and a full opening at the bottom, flanges A and B at both ends of the truss beam, with the U-shaped opening facing the ground. Flange A is fixedly connected to the flange of the connecting body at the center of the concentrator, and the main beam is located on the non-concentrating side of the concentrator; one end of the steel cable is fixed to the end of the radiating beam in the concentrator, and the other end is fixed to flange B of the main beam; the dual-axis tracking device includes an azimuth tracking device fixed and coaxially connected to the flange at the top of the supporting column, a column C fixedly coaxially to the other moving end of the azimuth tracking device, a spiral lift that drives the concentrator and the main beam to pitch together, and bearing seat B. The system comprises a bearing housing A and a support shaft fixed to the top of column C; the rotation axis of the orientation tracking device is perpendicular to the ground plane, and the axis of the support shaft is perpendicular to the rotation axis of the orientation tracking device; the side wall of column C is provided with a hinge, which is connected to the end of the telescopic screw of the screw jack by a pin, and the axis of the hinge is parallel to the axis of the support shaft; the rotating shaft of the base of the screw jack is installed on the upper chord of the main beam through bearing housing B, and the two bearing housings B are arranged coaxially along the two upper chords of the main beam, and the axis of the bearing housing B is parallel to the axis of the hinge; a bearing housing A is fixed coaxially on each of the two lower chords of the main beam, and the two journals of the support shaft are respectively installed in the two bearing housings A.The liquid volume regulation system includes a liquid storage tank located on the upper chord of the main beam and capable of sliding and adjusting its position along the length of the upper chord; a pump and control system for regulating the liquid level in the liquid storage tank and the liquid storage bag; and several solenoid valves, one end of which is connected to the pump and the other end of which are connected to the liquid storage bag.

2. The solar dish concentrator system with low wind load and damping vibration reduction according to claim 1, characterized in that: The liquid storage tank has a cubic or spherical cavity structure, and the liquid storage rate inside the cavity is 30%~50%. The liquid storage tank is fixed on the slide of the lead screw sliding platform for position adjustment, and the lead screw sliding platform is fixed on the upper chord of the main beam. The solenoid valve is a multi-way selection valve, which selects the liquid storage tank to connect with any one of the liquid storage bags and independently adjusts its liquid storage rate. The pump is a bidirectional pump that can pump liquid bidirectionally between the liquid storage tank and the liquid storage bag. The liquid storage rate inside the liquid storage bag is 20%~40%.

3. The solar dish concentrator system with low wind load and damping vibration reduction according to claim 1, characterized in that: The liquid medium contained in the storage bag is water, silicone oil, mineral oil, glycerol aqueous solution, or antifreeze liquid ethylene glycol aqueous solution.

4. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The supporting column includes column A, which is fixed to the foundation at one end and has a conical structure with a smaller top and a larger bottom, and column B, which is coaxially fixed to the top end of column A; the orientation tracking device is a worm gear rotating disk, and the non-rotatable part of the orientation tracking device is coaxially fixed to the top end of column B by a flange.

5. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The liquid storage bag fixed on the cover is rectangular and located in the middle of two adjacent radiating beams, near the outer edge of the concentrator where the vibration amplitude is greatest. The liquid storage bag is made of weather-resistant elastic plastic, such as silicone, thermoplastic polyurethane elastomer, PVC flexible leather, or EPDM rubber. The cover is made of waterproof, windproof, and weather-resistant canvas, PVC membrane, glass fiber composite material, PTFE membrane, or ETFE membrane.

6. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The load-bearing frame is a frame structure made of high-strength carbon steel, high-strength aluminum alloy or carbon fiber composite material, and the screws extending from the back of the support back plate are made of carbon steel; the reflective element is a high-reflectivity glass silver mirror, a reflective film or a high-reflectivity nano-coating directly sprayed onto the surface of the load-bearing frame; the support back plate is a lightweight structure made of polyurethane, glass fiber and high-strength adhesive, and the surface is coated with a weather-resistant and waterproof coating.

7. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The bearing housing A is closer to the flange A side of the main beam than the bearing housing B. The main beam, the screw jack, and the column C form a planar pitching mechanism. The motor drives the screw jack to extend and retract, so that the main beam and the condenser pitch together. The focal axis of the condenser is perpendicular to the rotation axis of the condenser's pitching motion. The U-shaped opening of the main beam is larger than the supporting column and column C. When the condenser pitches to the point where the focal axis points to the zenith, the supporting column and column C are housed within this U-shaped opening.

8. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: One end of the damper is ball-jointed to the end of the lower chord of the radial beam, while the other end is ball-jointed to the center of the adjacent crossbar. Two dampers are provided between two adjacent radial beams. The damper is a piston-type viscous damper or a friction damper.

9. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The aforementioned steel cables are symmetrically distributed around the focal axis of the condenser, and one end of the steel cable is fixedly connected to the lower chord of the radiation beam in the condenser; the aforementioned optical functional surface is a parabolic surface, spherical surface or free optical surface, and the entire optical functional surface is divided radially and circumferentially to obtain the optical surface shape of each mirror unit.

10. A low-wind-load and damping-reduced solar dish concentrator system according to claim 1, characterized in that: The coordinates of the lower chord of the radiating beam used to determine the aerodynamic shape of the cover are determined as follows: Project the radiating beam onto a two-dimensional plane with its end pointing to the right. Establish the origin at the vertex of the optical functional surface. Using the vertically upward focal axis of the condenser as the +y axis and the horizontally to the right as the +x axis, the coordinates of the six inflection points of the lower chord of the radiating beam used to determine the aerodynamic shape of the cover are as follows: Point P1 coordinates are [0.10×R, -0.17×R], Point P2 coordinates are [0...]... The coordinates of point P3 are [0.24×R, -0.17×R], the coordinates of point P4 are [0.74×R, -0.04×R], the coordinates of point P5 are [0.91×R, 0.06×R], and the coordinates of point P6 are [1.0×R, 0.21×R]. Here, R is the light-collecting radius of the optical functional surface of the concentrator. The broken line obtained by connecting these 6 points with straight lines is the aerodynamic shape of the cover.

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