How does photovoltaic solar street lamp generate electricity? What are the configurations?

How does photovoltaic solar street lamp generate electricity? What are the configurations?



With the continuous development of photovoltaic technology, solar street lamps are becoming more and more common in our life. We all know that solar energy is converted into electric energy after sunlight in the daytime, and then stored by battery. At night, the battery is more light source to provide electric energy and achieve lighting effect.



So how does it make the light source convert into electric energy through solar panel and store it? Which configurations are involved in this process? Let's learn more about it.




I. solar street lamp photovoltaic module power generation principle



Solar street lamp can generate electricity mainly by using the photovoltaic effect of semiconductor materials, which can convert solar light radiation into electrical energy.



A solar cell is composed of n-type and p-type semiconductors. The junction of them is called p-n junction. When the solar cell receives the light, the p-n junction will release electrons and generate corresponding electron hole pairs because of obtaining the light energy.



The holes in the n-type semiconductor will move to the p-type, and the electrons in the p-type area will forget the n-type area, forming a current from the n-type area to the p-type area. When the external circuit is connected, there will be power output.




2. Power generation system configuration



Solar street lamp power generation system is mainly composed of solar panel, control and battery. If the output power is AC 220V or 110V, and the inverter is also involved, what role will they play in this process?




1. Solar panel



As the core part of the power generation system, the above also said that it mainly plays the role of converting light energy into electrical energy, and then sending it to the battery for storage, so as to facilitate lighting at night, or to promote load work.




2. Controller



The full name is solar charge and discharge controller. From this name, we can know its function. It is used to control the working state of the whole system and also plays a role of overcharge and over discharge protection for the battery.



The light control and time control functions of street lamp are also realized on the above, which can be selected according to the specific needs. If the temperature difference between the places where the solar street lamp is installed is relatively large, the controller often has the function of temperature compensation, so as to better adapt to the environment




3. Battery



In the past, lead-acid batteries were commonly used, but now they are gradually replaced by lithium iron phosphate batteries, mainly to store the electric energy converted by solar panels, and then release it when it is needed at night.




4. Inverter



The direct output of solar energy is generally 12V, 24V, 48V current voltage. If it is necessary to provide 220V, 110V AC power supply, it is necessary to use DC-AC inverter to convert the DC power generated by solar power generation system into AC power.



When some loads need to use multiple voltages, for example, 24V DC power needs to be converted into 5V DC power, then DC-DC inverter will be needed.