Brief answer to professional knowledge of photovoltaic power station

1. What is photovoltaic module?

Answer: photovoltaic module refers to the smallest and indivisible solar cell combination device with packaging and internal connection, which can independently provide DC power, also known as solar cell module.

2. What is a PV module string?

A: in the photovoltaic power generation system, several photovoltaic modules are connected in series to form a circuit unit with a certain DC output voltage, which is referred to as module string or group string for short.

3. What is a photovoltaic module array?

A: a DC power generation unit that mechanically and electrically assembles several photovoltaic modules and has a fixed support structure, also known as photovoltaic array.

4. What is PV module support?

A: the special support designed for placing, installing and fixing photovoltaic modules in the photovoltaic power generation system is referred to as the support for short.

5. What is monocrystalline silicon photovoltaic module?

A: monocrystalline silicon photovoltaic module is a photovoltaic module with high-purity monocrystalline silicon rod as raw material.

6. What is polysilicon PV module?

Answer: polycrystalline silicon photovoltaic module is a solar module composed of polycrystalline silicon high-efficiency solar cells arranged in different series and parallel arrays. It is composed of EVA adhesive film, tempered glass, light galvanized aluminum alloy, etc.

7. What is the attenuation rate of photovoltaic modules?

A: the attenuation rate refers to the percentage of the fluctuation amplitude of the regulated quantity reduced after each fluctuation cycle, that is, the ratio of the difference between the former amplitude and the latter amplitude of two adjacent waves in the same direction to the former amplitude.

8. What is the hidden crack of photovoltaic module?

A: the crack is a defect of the battery. Due to the characteristics of crystal structure, crystalline silicon cells are very easy to rupture. The process flow of crystalline silicon module production is long, and many links may cause hidden crack of battery chip. The essential reason for hidden crack can be summarized as mechanical stress or thermal stress on silicon chip.

9. What is the azimuth of PV module?

Answer: the azimuth of the PV module refers to the included angle between the projection of the normal of the PV module plane on the horizontal plane and the due south direction.

10. What is the tilt angle of PV module?

Answer: the inclination angle of photovoltaic module refers to the included angle between the plane and horizontal plane of photovoltaic module.

11. What is a fixed bracket?

A: the azimuth and inclination of the photovoltaic module array do not change with the moving track of the sun.

12. What is a tracking bracket?

Answer: there is at least one support whose azimuth and inclination angle of photovoltaic module array change with the moving track of the sun.

13. What is the conversion efficiency of photovoltaic modules?

A: the conversion efficiency of photovoltaic modules refers to the percentage of the maximum power output by the illuminated photovoltaic module and the total radiant power incident on the photovoltaic module.

14. What is the hot spot effect of photovoltaic modules?

A: under certain conditions, the shielded photovoltaic modules in a series branch will be used as a load to consume the energy generated by other photovoltaic modules. The internal resistance of the shielded photovoltaic modules increases and generates heat, which is the hot spot effect.

15. Hazards of hot spot effect of photovoltaic modules?

A: the hot spot effect will cause part of the energy generated by the photovoltaic module to be consumed by the shielded photovoltaic module, resulting in the power attenuation failure of the photovoltaic module, and even directly burn and scrap the photovoltaic module. The hot spot effect will reduce the voltage of the PV string circuit where it is located. The reduction of the circuit voltage will reduce the power of the PV string, and the inverter will withdraw from the grid in advance, which will directly affect the power generation.