The working principle of the solar panel in the off-grid system, the working principle of the crystal silicon N/P solar cell: When the P-type semiconductor and the N-type semiconductor are closely connected together, the P-N junction is formed at the interface of the two. When the photocell is irradiated by sunlight, the accumulation of positive and negative charges is formed on both sides of the P-N junction, resulting in photogenerated voltage and the formation of built-in electric field, which is the "photogenerated voltage effect".
In theory, at this point, if electrodes are drawn from both sides of the built-in electric field and an appropriate load is attached, a current will be generated and power will be generated on the load. Solar cell module is a solid device that uses the electronic characteristics of semiconductor materials to achieve P-V conversion.
The off-grid photovoltaic system is generally composed of photovoltaic array composed of solar cell modules, solar charge and discharge controller, battery pack, off-grid inverter, DC load and AC load. Solar cell module is the main part of the solar power supply system, and it is also the most valuable part of the solar power supply system. Solar charge and discharge controller, also known as "photovoltaic controller", its role is to adjust and control the electric energy sent by the solar cell module, to charge the battery to the maximum, and play the role of over-charge protection and over-discharge protection of the battery.
Where the temperature difference is large, the photovoltaic controller should have the function of temperature compensation. The main task of the battery group is to store energy, so that at night or rainy to ensure the load electricity.
Off-grid inverter is the core component of off-grid power generation system, which is responsible for converting direct current to alternating current for ac load. 1. Solar energy is inexhaustible and inexhaustible. The solar radiation received on the earth's surface can meet the global energy demand by 10,000 times. Installing solar photovoltaic systems on just 4% of the world's deserts could generate enough electricity to meet global demand. Solar power is safe and secure from energy crises or instability in fuel markets;
Solar energy can be everywhere, can be nearby power supply, do not have to long-distance transmission, avoid the loss of long-distance transmission lines;
Solar energy uses no fuel and is cheap to run;
Solar power generation without moving parts, not easy to use damage, simple maintenance, especially suitable for unattended use;
Solar power generation will not produce any waste, no pollution, noise and other public hazards, no adverse impact on the environment, is the ideal clean energy;
Solar power generation system construction cycle is short, convenient and flexible, and according to the increase and decrease of load, arbitrarily add or reduce the solar array capacity, to avoid waste.
