The data obtained from meteorological stations generally only include the total amount of solar radiation H on the horizontal plane, the direct radiation Hb, and the scattered radiation Hd, And there is: H=Hb+Hd for the total amount of solar radiation on the inclined plane and the principle of direct separation of solar radiation. For the total amount of solar radiation on the inclined plane and the principle of direct separation of solar radiation, it can be concluded that the total amount of solar radiation on the inclined plane, Ht, is composed of the direct solar radiation Hbt, the sky scattering Hdt, and the ground reflected radiation Hrt. Ht=Hbt+Hdt+Hrt
conclusion
1: The meteorological department provides the amount of radiation directly emitted and scattered by the sun on the horizontal plane, which is different from our actual application.
2: The direct tilt angle design of grid connected solar cells only needs to consider the maximum annual total power generation, which is much simpler compared to independent power generation systems.
3: The specific approach can be achieved by looking up tables or using software.
temperature characteristic
summary
When the temperature rises by 1 ℃, the maximum output power of crystalline silicon solar cells decreases by 0.04% ℃, the open circuit voltage decreases by 0.04% (- 2mv/℃), and the short circuit current increases by 0.04%.
To avoid the impact of temperature on power generation, good ventilation conditions should be maintained for the components.
6: Dust loss
The dust loss of the power plant may reach 6%! Therefore, components require frequent wiping.
7: Maximum Output Power Tracking (MPPT)
summary
From the perspective of solar cell application, the so-called application refers to tracking the maximum output power point of solar cells. The MPPT function of the grid connected system is completed in the inverter. Recently, someone has studied placing it in a DC combiner box.