Measuring Solar Cells
Measurement of the electrical straincurve (IV-curve) of a solar cell
Solar cells can be electrically characterised by measuring the diode characteristic. The results are recorded in the, so called IV curve. From the IV curve the specific charateristics are being derived, like the short cut current (Isc), the open clamp charge (Voc), the maximum power (Pmpp) and the fillfactor (FF). The IV curve is normally determined under standard testing conditions (see paragraph below). However, the IV characteristic can also be measured as function of the amount of light and temperature of the solar cell.
STC measurements
To compare solar cells there is a worldwide agreement on 'standard' measurement condition. This is the Standard Test Condition (STC). The irradiation is 1000 W/m2, the spectrum Air Mass (AM) 1.5 and the cell temperature 25ºC. N.B.; for proceeds predictions etc. it is also interesting to know what the behaviour of the solar cell will be in other irradiation conditions for instance less then the 1000 W/m2 STC, possibly in combination with different temperatures.
TC (Temperature dependency)
The performances of a solar cell depends on the cell temperature. Therefor, it is important to know what the temperature dependency of a certain electrical quantity is. The temperature dependant behaviour can strongly differ per cell material or per cell technology.
