Photovoltaic system power generation issue series 2
Why does the power generation decrease as the weather gets better?
Answer: In summer, the power generation of photovoltaic power plants may not be as high as in spring or autumn when it is sunny, because the continuous high temperature in summer has a great impact on the components. When the temperature rises, the output power of the components will decrease, and the power generation will decrease by about 0.44% for every degree increase.
Why do systems with more string blocks have smaller current than those with fewer string blocks?
Answer: Under the same conditions, as the number of components increases, the voltage accumulates, but the current remains the same. This abnormal situation may be caused by string mismatch (different models, inconsistent attenuation, inconsistent line loss, shading, etc.).
Should the inverter grounding and the shell grounding be connected in one place?
Answer: The inverter grounding and the shell grounding should not be connected in one place and need to be separated. The former is the working grounding (which can maintain the relative ground voltage unchanged in non-fault conditions; can ensure the accuracy of low voltage measurement in the primary system; and can release lightning current to the ground during thunderstorms), while the latter is the protective grounding (in order to protect personal safety and avoid or reduce the harm of accidents, protective grounding is often used in electrical engineering).
If the distribution box trips due to leakage protection, the AC cable insulation is normal, and it trips once every morning with normal wiring, what is the reason?
Answer: There may be two reasons:
1) Improper selection, the leakage protection value is too small;
2) There is leakage in the circuit, which may be related to grounding or insulation.