ã€China Aluminum Industry Net】 The photovoltaic bracket made of aluminum is an important part of the photovoltaic power station made of aluminum. It carries the power generation main body of the photovoltaic power station made of aluminum. The choice of bracket directly affects the photovoltaic components made of aluminum. Operational safety, damage rate and construction investment, and choosing the right PV stent made of aluminum profiles will not only reduce the project cost, but also reduce the cost of post-construction maintenance. First, the type of photovoltaic bracket made of aluminum 1, according to the material classification According to the different materials used for the photovoltaic support made of aluminum profiles, it can be divided into aluminum alloy stents, steel stents and non-metallic stents, of which non-metallic stents are less used, and aluminum alloy stents and steel stents are each There are features. 2, according to the installation method Second, the introduction of fixed aluminum production of photovoltaic stent The photovoltaic array produced by aluminum profiles does not rotate with the change of the incident angle of the sun and receives solar radiation in a fixed manner. According to the setting of the inclination angle, it can be divided into: preferred inclination-fixed type, inclined roof-fixed type, and inclined-angle-adjustable fixed type. 1, better inclination angle fixed First, calculate the best installation inclination in the area, and then use all the arrays to install the inclination angle. Currently, it is widely used in flat roof roof power stations and ground power stations. 1) Flat roof - concrete foundation bracket The flat roof concrete foundation support is the most common installation type in the current flat roof power station. According to the basic form, it can be divided into strip foundation and independent foundation; the connection mode between the support pillar and the foundation can be connected through anchor bolts or directly support Column embedded in concrete foundation. Advantages: good wind resistance, strong reliability, does not damage the roof waterproof structure. Disadvantages: Need to make a good concrete foundation, and to maintain enough strength to carry out follow-up bracket installation, construction period is longer. 2) Flat Roof - Concrete Ballast Advantages: The construction method of concrete ballast supports is simple. It can be installed at the same time when making counterweight blocks, saving construction time. Disadvantages: The concrete ballast support has relatively poor wind resistance, and it is necessary to fully consider the local wind force when designing the counterweight weight. 3) Ground Power Station - Concrete Foundation Bracket There are various types of concrete foundation supports for ground power stations. According to the geological conditions of different projects, the corresponding installation methods can be selected. The following are the general types of in-situ reinforced concrete foundations, independent and strip concrete foundations, and precast concrete hollow column foundations. Concrete foundation installation form. Cast-in-situ reinforced concrete foundation According to the different basic forms, the cast-in-place reinforced concrete foundation can be divided into cast-in-place concrete piles and pouring anchors. Advantages: In-situ cast reinforced concrete foundation has less earthwork for excavation, less concrete reinforcement, lower cost, and faster construction. Disadvantages: Construction of cast-in-place reinforced concrete foundations is vulnerable to environmental factors such as seasons and weather. Construction requirements are high and once they are ready they cannot be adjusted. Independent and strip concrete foundation Advantages: The independent and strip concrete foundation adopts the reinforced expansion foundation, the construction method is simple, the geological adaptability is strong, and the foundation embedding depth can be relatively shallow. Disadvantages: Independent and strip-shaped concrete foundation projects have large quantities, require many labors, earth excavation and backfilling, long construction period, and great damage to the environment. Precast concrete hollow column foundation The prefabricated concrete hollow column foundation is widely used in power stations with poor geological conditions, such as water-solar hybrid power stations and tidal flat power stations. At the same time, due to the advantages of basic height, it is also used in mountainous power stations and agricultural light complementary power stations. 4) Ground Power Station - Metal Pile Bracket Metal pile supports are also widely used in ground power stations. They can be divided into spiral pile foundation supports and impact pile foundation supports. Spiral pile foundation bracket Spiral pile bracket according to whether the flange plate can be divided into flange plate screw pile bracket and without the screw plate screw pile bracket; according to the shape of the cotyledons can be divided into narrow-leaf continuous spiral pile bracket and wide-leaf spacing spiral pile bracket. Spiral piles with flanges can be used for single-column installations or dual-column installations. Screw piles without flanges are generally used for twin-column installations. The pull-out resistance of the wide-leaf spacing spiral pile bracket is better than that of the narrow-leaf continuous spiral pile bracket. The wide-leaf spaced spiral pile bracket should be given priority in the windy area. Impact pile foundation bracket The impact pile foundation support, also called the metal fiber rod foundation support, mainly uses the pile driver to directly drive the C steel, H beam or other structural steel into the ground. This installation method is very simple, but the anti-pulling performance is poor. Advantages: For metal pile foundations, using pile drivers to drive steel piles into the ground, without excavating the ground, more environmentally friendly; not subject to seasonal temperature restrictions, can be implemented under a variety of climatic conditions including the northern winter; construction is quick and easy, Significantly shorten the construction period, can facilitate the migration and recovery; the foundation during the piling process is easy to adjust the height. Disadvantages: It is very difficult to piling in hard soil areas; piling in areas with more lithotripes is more likely to damage the galvanized layer; the use of anti-corrosion in saline areas is poor. 2, oblique roof fixed Considering the generally poor bearing capacity of the inclined roof, most of the components on the inclined roof are directly tiled. The azimuth and inclination of the components are generally the same as the roof. According to the difference of the inclined roof, it can be divided into tile roof installation system and light steel roof installation. system. 1) Tile roof installation system Tile roof installation system is mainly composed of hooks, guide rails, pressure blocks and bolts and other connections. 2) Lightweight steel roof installation system Light steel roof, also called color steel tile roof, is mainly used in industrial plants, warehouses, etc. According to different forms of color steel tile, it can be divided into angular relief light steel roof, standing seam steel roof and ladder type steel roof . Reclining light steel roofs and standing seam light steel roofs are mainly used as connecting pieces through fixtures to fix the rails on the roof, while the ladder type light steel roofs need to use self-tapping bolts to fix the connecting pieces on the roof. Regardless of the type of roofing, the measurements of “angle reliefâ€, “upright edge†and “trapezoid†dimensions must be taken when selecting the connection piece to ensure that the connection piece and the roof are matched, and that the ladder type light steel roof bracket must be installed. Good waterproof measures to avoid leaks at the bolt hole. 3, fixed tilt angle adjustable Adjustable inclination angle refers to the point of change in the incident angle of the sun, regular adjustment of the angle of the fixed bracket, increase the direct absorption of sunlight, increase the amount of power generation under a slight increase in the cost. Third, tracking aluminum production of photovoltaic stent Photovoltaic supports made of tracking aluminum profiles are used to make photovoltaic arrays made of aluminum profiles move with the change of the incident angle of the sun through electromechanical or hydraulic devices, so that sunlight can directly hit the panel of components and improve the photovoltaic array power generation capacity of aluminum profiles. The number of tracking axes can be divided into: single axis tracking system and dual axis tracking system. 1. Flat single axis tracking system The photovoltaic array produced by aluminum profiles can track the sun along a horizontal axis in the east-west direction, so as to obtain larger power generation, which is widely used in low-latitude regions. According to whether the north-south direction has an inclination, it can be divided into standard flat single-axis tracking type. And flat angle single axis tracking type. 2, oblique single axis tracking system The tracking axis sets a certain inclination angle to the south while rotating in the east-west direction, and rotates to track the sun azimuth around the tilt axis to obtain more power generation, which is suitable for applications in higher latitudes. 3, dual axis tracking system Using two axis rotations (vertical axis, horizontal axis) to track the sun's rays in real time, to ensure that the sun's rays are perpendicular to the component board at each moment, so as to obtain a larger amount of power generation, suitable for use in various latitudes. 4. Comparison of the operation modes of several brackets Photovoltaic stent made of aluminum material and comparison of aluminum material and choice of material strength Brackets generally use Q235B steel and aluminum extrusions 6063 T6, Intensity, 6063 T6 aluminum alloy is probably Q235 B steel is 68%-69%, so steel is generally superior to aluminum alloys in areas with strong winds and relatively large spans. Deflection deformation Deflection deformation of the structure is related to the shape and size of the profile and the modulus of elasticity (a parameter inherent in the material) and is not directly related to the strength of the material. Under the same conditions, the deformation of aluminum alloy is 2.9 times that of steel and the weight is 35% of steel. Under the same weight, the cost of aluminum alloy is 3 times that of steel. Therefore, it is generally in the strong wind area, the span is relatively large, the cost Conditions such as steel is superior to aluminum alloy profiles. Anti-corrosion At present, the main anti-corrosion method of the bracket steel is hot-dip galvanizing 55-80μm, aluminum alloy is anodized 5-10μm. Aluminum alloy in the atmosphere, in the passivation zone, the surface of a layer of dense oxide film, hinder the active aluminum substrate surface and the surrounding atmosphere contact, it has very good corrosion resistance, and the corrosion rate over time And decrease. Steel under normal conditions (C1-C4 environment), 80μm galvanized thickness can be used for more than 20 years, but in the high-humidity industrial zone or high-salinity seashore or even temperate seawater, the corrosion rate is accelerated, and the amount of galvanizing needs 100μm. Above and need regular maintenance every year. Aluminum alloys are far superior to steel in terms of corrosion protection. Other aspects of anti-corrosion (1) Appearance: Aluminum alloy profiles have a variety of surface treatment methods, such as anodizing, chemical polishing, fluorocarbon spraying, electrophoretic painting, etc. Appearance is beautiful and can adapt to a variety of strong corrosive environments. Steel is generally used hot-dip galvanizing, surface spraying, paint coating, etc. Appearance worse than aluminum profiles. In corrosion protection is also worse than aluminum. (2) Cross-section diversity The general processing methods of aluminum alloy extrusions include extrusion, casting, bending, stamping, etc. The extrusion production is the current mainstream production method. By opening the extrusion die, any arbitrary section profile can be produced, and the production speed is relatively fast. . Rolling, casting, bending, stamping, and other methods are commonly used for steel. At present, roller pressure is the main production method for producing cold-formed steel. The cross-section needs to be adjusted by a roller wheel set, but the general machine can only produce similar products after setting. , Size adjustment, and cross-sectional shape can not be changed, such as C-section steel, Z-section and other cross-section. Roller production is relatively fixed, the production speed is relatively fast. Material recovery The maintenance cost of the steel structure increases by 3% every year, and the aluminum structure bracket hardly needs any maintenance and maintenance. The aluminum material still has 65% recovery rate after 30 years. The aluminum price is expected to increase by 3% every year. The steel structure is After 30 years is basically a pile of scrap iron, no recycling value. Comprehensive performance comparison (1) Aluminum alloy profiles are light in weight, beautiful in appearance, and excellent in corrosion resistance. They are generally used in home roof power stations and strong corrosive environments where load-bearing requirements are required. (2) Steel has high strength and small deflection when subjected to load. It is generally used for ordinary power plants or for components with large stress. (3) Cost: Under normal circumstances, the basic air pressure is 0.6kN/m2, and the span is less than 2m. The cost of aluminum alloy brackets is 1.3-1.5 times that of the steel structure brackets. In the small-span system, (such as the color steel plate roof) The cost difference between the aluminum alloy bracket and the steel structure bracket is relatively small, and the aluminum alloy is lighter than the steel bracket in terms of weight, so it is very suitable for home roof power stations.