太阳能光伏发电，你了解多少

《光伏发电概念》

光伏发电是利用半导体界面的光生伏特效应而将光能直接转变为电能的一种技术。主要由太阳电池板（组件）、控制器和逆变器三大部分组成，主要部件由电子元器件构成。太阳能电池经过串联后进行封装保护可形成大面积的太阳电池组件，再配合上功率控制器等部件就形成了光伏发电装置。

《光伏发电的原理》

光伏发电的主要原理是半导体的光电效应。光子照射到金属上时，它的能量可以被金属中某个电子全部吸收，电子吸收的能量足够大，能克服金属内部引力做功，离开金属表面逃逸出来，成为光电子。硅原子有4个外层电子，如果在纯硅中掺入有5个外层电子的原子如磷原子，就成为N型半导体；若在纯硅中掺入有3个外层电子的原子如硼原子，形成P型半导体。当P型和N型结合在一起时，接触面就会形成电势差，成为太阳能电池。当太阳光照射到P－N结后，空穴由P极区往N极区移动，电子由N极区向P极区移动，形成电流。

常规光伏电站是利用太阳能电池板吸收太阳光中的可见光形成光电子，产生电流。

《光伏发电优点》

①无枯竭危险；

②安全可靠，无噪声，无污染排放外，绝对干净（无公害）；

③不受资源分布地域的限制，可利用建筑屋面的优势；例如，无电地区，以及地形复杂地区；

④无需消耗燃料和架设输电线路即可就地发电供电；

⑤能源质量高；

⑥使用者从感情上容易接受；

⑦建设周期短，获取能源花费的时间短。

常规的光伏发电技术，在我国已经发展稳定，技术相对成熟，

《主要结构组成》

太阳能电池板：将太阳的辐射能力转换为电能，或送往蓄电池中存储起来，或推动负载工作。一般为硅电池，分为单晶硅太阳能电池，多晶硅太阳能电池和非晶硅太阳能电池三种。单一组件的发电量是十分有限的，实际运用中，是单一组件通过电缆和汇线盒实现组件的串、并联，组成整个的组件系统，称为光伏阵列。

控制器 ：独立光伏发电系统中非常重要的部件，是能自动防止蓄电池过度充电和过度放电的设备，在温差较大的地方，控制器还应具备温度补偿的功能。

逆变器 ：太阳能的直接输出一般都是12VDC、24VDC、48VDC。为220VAC的电器提供电能，需要将太阳能发电系统所发出的直流电能转换成交流电能。一般分为独立逆变器和并网逆变器。

《系统分类》

（1）独立光伏发电

独立光伏发电也叫离网光伏发电。太阳能发电储存到胶体蓄电池，然后给负荷供电。主要由太阳能电池组件、控制器、蓄电池组成，若要为交流负载供电，还需要配置交流逆变器。

（2）并网光伏发电

并网光伏发电就是太阳能组件产生的直流电经过并网逆变器转换成符合市电电网要求的交流电之后直接接入公共电网。

（3）分布式光伏发电

分布式光伏发电又称分散式发电或分布式供能，是指在用户现场或靠近用电现场配置较小的光伏发电供电系统，以满足特定用户的需求。

Principles and Significance of Photovoltaic Power Generation in Photovoltaic Construction and Operation

1. What is photovoltaic power generation



Photovoltaic power generation specifically refers to a power generation system that uses photovoltaic modules to directly convert solar energy into electrical energy. It is a new and promising method of power generation and energy comprehensive utilization, and is the mainstream of solar power generation today.




2. What is a distributed photovoltaic system



Distributed photovoltaic systems refer to photovoltaic power generation facilities that are built near user sites and generally connected to power grids with voltage levels below 35kV. The generated electricity is mainly consumed locally and is characterized by balanced regulation in the distribution system.




3. Operation mode of distributed optical optimization system



There are three modes of operation for distributed optical optimization systems: full self use, self use of surplus electricity, and full grid access. Full self use refers to the total consumption of electricity generated by the photovoltaic power generation system; Spontaneous self use of surplus electricity for grid connection refers to the priority use of electricity generated by photovoltaic power generation systems by power users, with excess electricity connected to the grid; Full grid connection refers to the complete connection of the electricity generated by the photovoltaic power generation system to the power grid. Concept of Photovoltaic Power Generation

Photovoltaic power generation is a technology that utilizes the photovoltaic effect of semiconductor interfaces to directly convert light energy into electrical energy. It mainly consists of three parts: solar panels (components), controllers, and inverters, and the main components are composed of electronic components. After being connected in series and packaged for protection, solar cells can form a large area of solar cell components, which, in combination with power controllers and other components, form a photovoltaic power generation device.



Principles of Photovoltaic Power Generation

The main principle of photovoltaic power generation is the photoelectric effect of semiconductors. When a photon shines on a metal, its energy can be fully absorbed by a certain electron in the metal. The energy absorbed by the electron is large enough to overcome the internal gravity of the metal and do work, escape from the metal surface and become a photoelectron. Silicon atoms have 4 outer electrons. If an atom with 5 outer electrons, such as phosphorus atom, is doped into pure silicon, it becomes an N-type semiconductor; If atoms with three outer electrons, such as boron atoms, are doped into pure silicon, a P-type semiconductor is formed. When P-type and N-type are combined, the contact surface forms a potential difference, becoming a solar cell. When sunlight shines on the P-N junction, holes move from the P-pole region to the N-pole region, and electrons move from the N-pole region to the P-pole region, forming an electric current.



Conventional photovoltaic power plants use solar panels to absorb visible light from the sun, forming photoelectrons and generating electricity.