《光伏發(fā)電概念》

光伏發(fā)電是利用半導(dǎo)體界面的光生伏特效應(yīng)而將光能直接轉(zhuǎn)變?yōu)殡娔艿囊环N技術(shù)。主要由太陽電池板（組件）、控制器和逆變器三大部分組成，主要部件由電子元器件構(gòu)成。太陽能電池經(jīng)過串聯(lián)后進(jìn)行封裝保護(hù)可形成大面積的太陽電池組件，再配合上功率控制器等部件就形成了光伏發(fā)電裝置。

《光伏發(fā)電的原理》

光伏發(fā)電的主要原理是半導(dǎo)體的光電效應(yīng)。光子照射到金屬上時，它的能量可以被金屬中某個電子全部吸收，電子吸收的能量足夠大，能克服金屬內(nèi)部引力做功，離開金屬表面逃逸出來，成為光電子。硅原子有4個外層電子，如果在純硅中摻入有5個外層電子的原子如磷原子，就成為N型半導(dǎo)體；若在純硅中摻入有3個外層電子的原子如硼原子，形成P型半導(dǎo)體。當(dāng)P型和N型結(jié)合在一起時，接觸面就會形成電勢差，成為太陽能電池。當(dāng)太陽光照射到P－N結(jié)后，空穴由P極區(qū)往N極區(qū)移動，電子由N極區(qū)向P極區(qū)移動，形成電流。

常規(guī)光伏電站是利用太陽能電池板吸收太陽光中的可見光形成光電子，產(chǎn)生電流。

《光伏發(fā)電優(yōu)點(diǎn)》

①無枯竭危險；

②安全可靠，無噪聲，無污染排放外，絕對干凈（無公害）；

③不受資源分布地域的限制，可利用建筑屋面的優(yōu)勢；例如，無電地區(qū)，以及地形復(fù)雜地區(qū)；

④無需消耗燃料和架設(shè)輸電線路即可就地發(fā)電供電；

⑤能源質(zhì)量高；

⑥使用者從感情上容易接受；

⑦建設(shè)周期短，獲取能源花費(fèi)的時間短。

常規(guī)的光伏發(fā)電技術(shù)，在我國已經(jīng)發(fā)展穩(wěn)定，技術(shù)相對成熟，

《主要結(jié)構(gòu)組成》

太陽能電池板：將太陽的輻射能力轉(zhuǎn)換為電能，或送往蓄電池中存儲起來，或推動負(fù)載工作。一般為硅電池，分為單晶硅太陽能電池，多晶硅太陽能電池和非晶硅太陽能電池三種。單一組件的發(fā)電量是十分有限的，實(shí)際運(yùn)用中，是單一組件通過電纜和匯線盒實(shí)現(xiàn)組件的串、并聯(lián)，組成整個的組件系統(tǒng)，稱為光伏陣列。

控制器 ：獨(dú)立光伏發(fā)電系統(tǒng)中非常重要的部件，是能自動防止蓄電池過度充電和過度放電的設(shè)備，在溫差較大的地方，控制器還應(yīng)具備溫度補(bǔ)償?shù)墓δ堋?/span>

逆變器 ：太陽能的直接輸出一般都是12VDC、24VDC、48VDC。為220VAC的電器提供電能，需要將太陽能發(fā)電系統(tǒng)所發(fā)出的直流電能轉(zhuǎn)換成交流電能。一般分為獨(dú)立逆變器和并網(wǎng)逆變器。

《系統(tǒng)分類》

（1）獨(dú)立光伏發(fā)電

獨(dú)立光伏發(fā)電也叫離網(wǎng)光伏發(fā)電。太陽能發(fā)電儲存到膠體蓄電池，然后給負(fù)荷供電。主要由太陽能電池組件、控制器、蓄電池組成，若要為交流負(fù)載供電，還需要配置交流逆變器。

（2）并網(wǎng)光伏發(fā)電

并網(wǎng)光伏發(fā)電就是太陽能組件產(chǎn)生的直流電經(jīng)過并網(wǎng)逆變器轉(zhuǎn)換成符合市電電網(wǎng)要求的交流電之后直接接入公共電網(wǎng)。

（3）分布式光伏發(fā)電

分布式光伏發(fā)電又稱分散式發(fā)電或分布式供能，是指在用戶現(xiàn)場或靠近用電現(xiàn)場配置較小的光伏發(fā)電供電系統(tǒng)，以滿足特定用戶的需求。

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.