Photovoltaic grid-connected power generation systems are processes that are powered by solar cells and grid-connected inverters. Photovoltaic grid-connected power generation systems are widely used in today’s life. The light energy of photovoltaic grid-connected power generation systems is converted into electrical energy. z profile steel,Various advantages and functions are supported and researched by professionals and national governments. Our research direction also revolves around Grid-connected inverter and photovoltaic cells. Their equipment has also been very hot in the market, and now solar products have been popularized to home users, so some basic concepts and principles are explained.
1. Grid-connected inverter
The grid-connected inverter has the following types of inverters:
(1) Centralized inverter
(2) String inverter
(3) Component inverter
The main circuit of the above several inverters is based on the control circuit. We can be divided into two methods: square wave and sine wave.
Inverter for square wave output: Most of the inverters for square wave output are pulse width modulation integrated circuits, such as TL494. The facts show that the SG3525 integrated circuit is used to access the power FET as the switching power component, which can achieve the performance of the inverter. The SG3525 is very effective in driving the power FET and has an internal reference source and operational amplifier. And undervoltage protection, all relative peripheral circuits are also very simple.
Sinusoidal output inverter: Sinusoidal inverter schematic, with the difference between square wave output and sine wave output. The square wave output inverter is high efficiency, but for all electrical appliances designed for sine wave power supply Said, the use is always not assured, although it can be applied to many electrical appliances, but some electrical appliances are not applicable, or the indicators of electrical appliances used will change. Sinusoidal output inverters have no such shortcomings, but there are inefficiencies Disadvantages.
The principle of the grid-connected inverter: The current that converts the alternating current into direct current is rectification. The circuit process that completes this rectification function is called the rectifier circuit. The realization process of the whole rectifier circuit device becomes the rectifier. Compared with it, the current that can convert the DC current into AC current is the reverse current. The circuit that completes the entire reverse current function is called the inverter circuit. The realization process of the whole inverter device becomes the inverter.
2. Photovoltaic cells
Concept: Photovoltaic support is the direct conversion of light energy into electrical energy. At present, we are using silicon as a material to manufacture silicon solar cells.
Principle: The photovoltaic effect is a phenomenon in which the surface of the product is subjected to electromotive force generated by solar photons. When the surface of the product is exposed to light, the state of charge distribution in the product changes to produce an electromotive force and current. When the light illuminates the PN junction of the semiconductor, a photovoltaic effect occurs. The photovoltaic effect causes voltages to appear on both sides of the PN junction, called photo-generated voltage. Shorting the PN junction produces a current.
Construction: The white thin wires and thick wires attached to the surface of the battery are collectively referred to as positive silver in the battery manufacturer, and if they are separately said, the fine grid lines and the main grid lines. The main function of the fine grid line is to collect the current on the surface of the cell and collect it into the main gate line. The function of the main gate line is to concentrate the current on the two gate lines, and then the current is guided by the downstream manufacturers through soldering. . The two thick lines on the back of the cell are also silver, and the so-called back silver action is consistent with the front main gate line. The P/N junction is obtained by a diffusion process, and its position is a few micrometers below the blue coating surface. The depth of the PN junction is related to the diffusion process temperature and gas concentration at that time.
1). Simplified selection: Optimize with 2 products
2). All products including remote alarm contacts
3). The overall safety of the box at the end of its useful life
4). The thermal circuit breaker will open automatically before the damage is broken.
3. Photovoltaic grid-connected power generation system
Photovoltaic grid-connected power generation system is the direct current generated by solar energy products. After the inverter is converted into alternating current, it is directly connected to the public power grid. Simply put, it is converted from light energy into electric energy for users to use.
Because the electrical energy can be directly input to the grid, the photovoltaic independent system in all the batteries will be replaced by the grid-connected system, so do not install the battery, which will reduce the cost. However, the grid-connected inverter required by the system must ensure that the power can meet the frequency and frequency of the grid.Steel Profile suppliers
(1) The use of non-polluting, renewable solar power generation, also reduces non-renewable. The consumption of energy resources with limited resources, the emission of greenhouse gases and polluting gases during the use of the noon, and the harmony of the ecological environment are the development of the road to sustainable development!
(2) The power generated by the inverter directly enters the grid through the inverter, eliminating the storage battery, and the construction investment of the photovoltaic independent system can be reduced by 35% to 45%, which greatly reduces the production cost. It can also remove the battery to avoid secondary pollution of the battery, and can increase the service life and normal use time of the system.
(3) Photovoltaic building integrated power generation system, due to small investment, fast construction, small floor space, high building technology content, and enhanced construction selling point
(4) Distributed construction, scattered construction near the local and small places, making it convenient to enter the power grid, not only good at increasing the defense ability of the system and resisting natural disasters, but also good at load balancing of the power system and reducing the loss of the line.
(5) It can function as a peak. Grid-connected solar photovoltaic system is a key target and support project for many developed countries. It is the main development trend of solar power generation system, with large market capacity and large development space.