Photovoltaics is one of the fastest growing fields of electrotechnics. In the last decades we have seen an emerge of new technologies, that prolong the effective lifetime of minority charge carriers in result those modules express large diffusion capacitances.
For the purpose of this thesis we performed an overview of measurement methods for measuring IV curve. We described the measurement methods with active loads and capacitive banks with their strengths and weaknesses.
We created a SPICE model of a general PV module and performed verification on two technologies TOPCon and HIT. From measurements on 1, 2 and 3 PV modules, we extrapolated the PV string to a 1000 V PV string.
From the extrapolated model we analysed the hardware requirements for measuring PV modules with high efficiencies. The objective was to predict hardware requirements for measuring the IV curve of TOPCon with less than 1,5 % systematic measurement error and HIT with 3 % systematic measurement error. For the method with active load, we describe a recursive measurement approach that predicted the need for 8 power transistors.
For the capacitive method we predicted the use of two capacitors with capacitance of 1,8 mF and rated voltage of 600 V. We also described the issues of short circuiting the PV string, which is the first step before taking the IV measurement with the capacitive approach.
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