3.92Kwp Hyundai Array using Fronius IGTL3.6 Inverter, Halesowen, West Midlands
Electrical Properties of PV Cells
The principal electrical properties of a photovoltaic cell are its current and voltage. The current produced by the cell depends on the quantity of light falling on the cell, its surface area and the voltage it is operating at.The cell output voltage is relatively independent of the level of solar radiation.
Figure 1 Insolation I-V Curve
The relationship between current and voltage in a cell is described by its I-V curve. PV devices can operate from open circuit (zero current) down to short circuit (zero voltage). Between these two extremes maximum power is produced at 80% of the open circuit voltage for crystalline PV (60% for amorphous silicon) this is the maximum power point
Figure 2 Maximum Power Point I-V Curve
PV performance is also affected by cell temperature and shading. PV efficiency reduces as temperature rises and this has an impact on system efficiency and thus on the mounting system used for the PV modules.
Figure 3 Cell Temperature I-V Curve