Solar Power System
Solar power system structure and working principle
Solar power is the use of solar energy battery components directly into electrical energy. Solar Module (Solar cells) is the use of electronic characteristic of semiconductor materials to achieve solid PV conversion device, in the vast off-grid areas, the device can be easily implemented as user-powered lighting and living, and some developed countries also regional power grid to achieve complementarity. Current from the civilian point of view, mature technology in foreign countries, and begun to take industry is “PV – Building (lighting) integration” technology, while the domestic production of major research areas without electricity for a small solar home lighting power generation systems.
Principles of solar power
Solar power generation system include: solar module (array), controller, batteries, inverters, lighting load that is composed of the user. Among them, the solar battery components and batteries for the power system, controller and inverter for the control and protection system, the load for the system terminals.
Solar power system
Solar cell and battery components of the system power supply unit, so a direct impact on battery performance characteristics of the system work.
Battery Unit:
As technology and material reasons, a single cell generating capacity is very limited, practical solar cells in a single cell by series and parallel to form a battery system, called the battery components (arrays). Single cell is a silicon diode, according to the electronic characteristic of semiconductor materials, when the sun light shines from the P-type and N-type conductivity of two different types of homogenous composition of semiconductor materials when the PN junction, under certain conditions , solar radiation absorbed by the semiconductor material in the conduction band and valence band of non-equilibrium carrier generation is electron and hole. Barrier at the PN junction with the existence of strong built-in area electrostatic field, which can be formed in the light of the current density J, short-circuit current Isc, open circuit voltage Uoc. If the sides of the built-in electric field leads to the electrode and connected to the load, by the PN junction theory, the connection circuit and the load form the loop, there is “photo-current” flows through the solar modules to achieve the power of the load P output.
Theoretical studies have shown that the peak power of solar modules Pk, by the local solar radiation intensity and the end of the average electricity load (electricity demand) decisions.
Electrical Energy Storage Unit:
Solar cells produce direct current into the battery before storage, the battery characteristics of the system’s efficiency and features. Battery technology is very mature, but its capacity to take power by the end of the sunshine time (generation time) effects. Watt-hour battery capacity and therefore the amount of the intended consecutive An Shirong no sunshine decision.
Controller
Controller’s main function is to make solar power system is always in the vicinity of the maximum power generation in order to obtain maximum efficiency. The charge control usually the PWM pulse width modulation control, so that the whole system is always running at maximum power point Pm near the area. Discharge control mainly refers to when the battery power shortage, system failures, such as open or reversed when the battery cut off switch. Currently both Hitachi developed a tracking control point Pm, and can track the sun moving parameter of the “sunflower” type of controller, the battery components will be fixed about 50% efficiency.
DC-AC inverter
Inverter by incentives can be divided into self-excited oscillation inverter and his excited oscillation inverter. Main function is to the DC battery
The inverse into alternating current. Through the full bridge circuit, generally modulated SPWM processor, filter, boost, etc., are with the photos
Ming load frequency f, the rated voltage matches the sinusoidal alternating current UN and other end users for the system.
Conclusion
Green energy and sustainable development issues facing humanity this century is a major issue, the development of new energy, full of rational use of existing energy has been great attention of Governments. Solar power as an inexhaustible supply of clean green energy will be an unprecedented development. With the solar energy industry and technology development process of the deepening of its efficiency, cost will be increased, which includes all areas, including BIPV will be widely used, it will greatly promote China’s “Green Lights” fast development.