Selection of solar cell module types
Solar cell modules are divided into monocrystalline silicon, polycrystalline silicon, amorphous silicon and non-silicon, etc. The commercial applications are mainly monocrystalline silicon, polycrystalline silicon and amorphous silicon. The designed solar LED lighting system should use high-quality monocrystalline silicon cells. The theoretical basis is that monocrystalline silicon cells have small attenuation, small parameter dispersion, stable maximum power output performance, good consistency and high conversion rate. Polycrystalline silicon batteries can be selected for the design of solar LED lawn lights and solar LED signal lights.
The electrical parameters of the solar cell modules selected in the design must be strictly consistent. Because the solar cell array is composed of one or more solar cell modules, the current and voltage of the solar cell modules should be basically the same to reduce the loss of series and parallel combination. If it is sometimes unavoidable that the sun is blocked for part of the day, bypass diodes should be installed on each component to avoid reducing the output power of the phalanx.
In a large-capacity solar LED lighting system, many solar cell modules are often connected in series and parallel to meet the needs of the load. Due to the fact that the performance parameters of each solar cell cannot be completely kept the same during the manufacturing process, when packaging the modules, it is necessary to select and select the single solar cells, so that the working currents are similar to each other in a group. Otherwise, as long as the operating current of one solar cell is low, it will affect the current output of the entire string of solar cells. Similarly, when installing a large-capacity solar LED lighting system, due to the differences in the performance of each component, the ones with similar working currents should also be connected together, and the ones with similar working voltages should be selected in parallel, otherwise it will affect the total output power.
Wind-resistant design of solar cell module bracket
The solar cell array bracket is used to support the solar cell module. The structure design of the solar cell array should ensure that the connection between the solar cell module and the bracket is firm and reliable, and the solar cell module can be easily replaced. All phalanx fasteners must have sufficient strength to securely fasten the solar cell module to the phalanx support. The solar cell array and support must be able to withstand 120km/h wind without being damaged.
When the solar cell array bracket is installed, its inclination angle (adjustable or fixed) should enable the solar cell array to obtain the maximum power generation in the design month (that is, the month with the worst average daily radiation). All phalanx fasteners must have sufficient strength to securely fasten the solar cell module to the bracket.
In the structural design of the solar lighting system, a problem that needs to be paid great attention is the wind resistance design. According to the technical parameters of the solar cell module manufacturer, the windward pressure that the solar cell module can withstand is 2700Pa. If the wind resistance coefficient is selected as 27m/s (equivalent to a tenth-level typhoon), according to the inviscid hydrodynamics, the wind pressure that the solar cell module bears is only 365Pa. Therefore, the component itself can fully withstand the wind speed of 27m/s without damage. Therefore, the key considerations in the design are the solar cell array bracket design, the foundation (light pole) design and the connection design between the bracket and the foundation (light pole). The connection design between the solar cell module bracket and the foundation (light pole) should be bolted.