VALIDITY ANALYSIS OF THE TEXT BOOK LUMPED SERIES RESISTANCE APPROACH FOR SOLAR CELLS

摘要

In this paper, the influence of the voltage variations due to sources of series resistance on the solar cell cell J- V curve is investigated. At first, the text book lumping approach for series resistance with its assumptions is explained. Then, the local diode equation is expanded as a Taylor series to analyse what happens for small voltage variations. Afterwards, the concept of a series resistance calculation based on voltage averaging is introduced. The voltage averaging approach is more intuitive and easier to grasp, and is proven to be exactly equivalent to the text book approach. Finally, the average current density in between two fingers will be calculated with a correct method for current density averaging and compared to the value predicted by the text book approach to check its validity. It is found that the text book approach is quite accurate for voltage variations that stay below the thermal voltage, but starts to deviate for higher values.