1. Design of the solar battery array
Unit solar batteries cannot be used directly as a power source. In practical application, several or dozens of single solar batteries are connected in series or in parallel according to the requirements of electrical performance, and after encapsulation, a smallest unit that can be used alone as a power source is formed, that is, a solar battery module. A solar battery array is an array of several solar battery modules connected in series and in parallel.
Solar battery array can be divided into two categories: flat panel type solar battery array and concentrator type solar battery array. The flat-panel solar battery array only needs to connect a certain number of solar batteries in series or parallel according to the requirements of electrical performance. It does not need to install a device for concentrating sunlight. The structure is simple, and it is mostly used for fixed installation occasions. Concentrating solar battery array is equipped with collectors for concentrating sunlight, usually using flat reflectors, parabolic reflectors or Fresnel lenses to condense light to improve the irradiance of the incident spectrum. Concentrated solar battery array can use fewer single solar batteries than flat-panel solar battery array with the same output power, thereby reducing the cost, but usually need to install a sun tracking device. With rotating parts, the solar energy is reduced. battery reliability.
The design of the solar battery array, in general, is to calculate the series and parallel numbers of solar battery modules according to the user's requirements and the power consumption and technical conditions of the load. The number of series connections is determined by the working voltage of the solar battery, and factors such as the floating charge voltage of the battery, line loss, and the influence of temperature changes on the solar battery should be considered. After the number of solar battery modules in series is determined, the number of solar battery modules in parallel can be determined according to the 10-year average of total solar radiation or annual sunshine hours provided by the meteorological station. The output power of the solar battery array is connected in series and parallel with the components to obtain the required current. The specific design and calculation method of the solar battery array is omitted here. General design principles and their relationship to the overall power generation system design.
2. Installation of solar battery array
The flat ground solar battery square array can be installed on the square array bracket, and the bracket is fixed on the cement foundation. The processing and construction of the cement foundation of the square matrix bracket and the fixed bracket and the cables connected to the controller shall be carried out in accordance with the design specifications. The basic requirements for the solar battery array support are as follows:
①The design and manufacture of solar battery array brackets should be carried out in accordance with the principles of material saving, low price, sturdiness and durability, and easy installation.
②The solar battery array bracket of the photovoltaic power station can be designed as a ground-mounted type or a roof-mounted type according to the actual situation of the application area and user requirements. The photovoltaic power stations above the kilowatt level in Tibet are mainly designed as ground-mounted brackets.
③ The solar battery array bracket should be made of steel or aluminum alloy material, and its strength should be able to withstand the blowing of a 10-level strong wind.
④The metal surface of the solar battery array bracket should be galvanized, aluminum-plated or painted with anti-rust paint to prevent rust and corrosion.
⑤ When designing the solar battery array support, factors such as local latitude and sunshine resources should be considered. It can also be designed to be able to manually adjust the solar inclination and azimuth of the solar battery array according to seasonal changes, so as to more fully receive solar radiation energy and increase the power generation of the array.
⑥ The connecting parts of the solar battery array bracket, including the connecting parts of the components and the brackets, the connecting parts of the brackets and the bolts, and the connecting parts of the bolts and the square array field, are all made of electroplated steel or stainless steel.
The power generation of the solar battery array is proportional to the solar radiation it receives. In order for the solar battery array to receive solar radiation more effectively, the installation orientation and inclination of the solar battery array are very important. A good solar battery array installation method is to track the sun, so that the surface of the solar battery array is always perpendicular to the sunlight, and the incident angle is 0°. Other incident angles will affect the reception of the phalanx to the sun, causing more losses. It is a more complicated problem to take the angle of the inclined plane of the solar battery array. In order to reduce the design error, the solar radiation energy on the horizontal plane obtained from the meteorological station should be converted into the corresponding value on the inclined plane of the square matrix during the design. The conversion method is to use the solar radiation energy received by the solar battery square array as a function of the latitude, inclination and solar declination of the place of use. A simple way is to use the average total solar radiation at the location of the solar battery array obtained from the weather station as the calculated ψ value. If the azimuth angle of the panel is adjusted twice a year, the total solar radiation gain will be about 6.5% compared with the horizontal placement of the square array.
3. Use and maintenance of solar battery array
The use and maintenance methods of solar battery arrays can be summarized into the following 10 items:
(1) The solar battery array should be installed in a place where there are no tall buildings, trees, poles, etc. around to block the sunlight, so that the sunlight can be fully obtained. my country is located in the northern hemisphere, and the lighting surface of the square array should face south and be perpendicular to the sun.
(2) During the installation and use of the solar battery array, the components should be handled with care, and collision, knocking, and scratching are strictly prohibited, so as not to damage the encapsulating glass, affect its performance, and shorten its service life.
(3) In case of strong wind, heavy rain, hail, heavy snow, etc., measures should be taken to protect the solar battery array so as not to damage it.
(4) The lighting surface of the solar battery array should be kept clean frequently. If there is dust or other dirt on the lighting surface, it should be rinsed with water first, and then gently wipe the water with a clean gauze. Do not use hard objects. Wipe or rinse with aggressive solvents.
(5) When connecting the output end of the solar battery array, pay attention to the positive and negative polarities, and do not connect them in reverse.
(6) The battery pack matched with the solar battery array should be used in strict accordance with the use and maintenance methods of the battery.
(7) For the solar battery array with the sunward tracking device, the tracking device should be checked and maintained frequently to ensure its normal operation.
(8) For the solar battery array whose angle can be adjusted manually, the sunward inclination and azimuth of the phalanx support should be adjusted according to the seasonal changes, so that it can fully receive solar radiation energy.
(9) The optoelectronic parameters of the solar battery array should be checked irregularly in accordance with the relevant methods during use, and problems should be solved in time to ensure the uninterrupted and normal power supply of the array.
(10) Guardrails or walls should be added around the solar battery array and its supporting equipment to avoid being invaded by animals or man-made damage. If the power generation equipment is installed on a high mountain, a lightning arrester should be installed to prevent lightning strikes.
Read more: The process of solar battery manufacturing