Capacitive tracer design to mitigate incomplete I-V curves in outdoor tests

The capacitance technique is the most straightforward and low-cost technique to trace the I-V curve of photovoltaic (PV) modules. Nevertheless, the sweep speed and number of samples to measure the I-V curve depend on the device under test (DUT), capacitance size, switching dynamic, lighting conditions, Etc. Therefore, two performance indexes were proposed to evaluate the I-V curve quality. The indexes were estimated from a circuital model considering the transient capacitance charging process as a function of the target irradiance levels and parameters of the DUT and tracer. In this way, a capacitance range is estimated to mitigate the likelihood of measuring incomplete curves in the I-sc and V-oc regions. Finally, the capacitance sizing design in terms of both indexes for monitoring PV technologies was validated in outdoor tests.

Automated summary

The capacitance technique is a straightforward and low-cost method to trace the I-V curve of photovoltaic modules. Two performance indexes were proposed to evaluate the curve quality, and a circuital model was used to estimate the capacitance range and reduce the likelihood of measuring incomplete curves. The capacitance sizing design for monitoring PV technologies was validated through outdoor tests.