Implementation of a plug and play Ⅰ-Ⅴ curve tracer dedicated to characterization and diagnosis of PV modules under real operating conditions

摘要

The performance assessment of operating photovoltaic modules under real conditions is a necessity. Engineers usually use commercial I-V curve tracers available in the market. Nevertheless, most of them are expensive and limited in the input voltage. This paper outlines a low-cost equipment for tracing current-voltage characteristics of photovoltaic systems using a relay to connect the operating module under test to the varying load, which is a power MOSFET transistor. The new developments of this work include the design of an RC circuit to generate a steady gate-source voltage amplitude controlled via a PWM varying duty cycle. Also, a flexible modular voltage measurement that consists of a voltage booster to increase the input voltage capacity of the developed curve tracer is proposed. This paper investigated the impact of PV module degradations such as discoloration, cell cracks, and PID on the I-V curve in the case of crystalline technology and compared to similar modules taken as reference.