IV Tracer For Photovoltaic Panel

Abstract

A device used for measuring the current-voltage characteristic of the photovoltaic panel has been developed. The circuit is built with the STM32F103C8, Arm based 32-bit microcontroller. The power MOSFET is used as the electronic load. The electronic load is controlled by varying the gate-source voltage between 0 to +3V. The voltage is detected with a voltage divider across the Panel's output terminal. The current is detected by the high wattage current sensor, 0.1 Ohms 10 Watt. The control firmware sweeps the gate voltage and captures the current-voltage signal with 56 sampling points. The current-voltage curve is plotted on the 128x64 pixels OLED display. The results show the maximum power point (P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">MAX</sub> ), open-circuit voltage (V <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">oc</sub> ), short-circuit current (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sc</sub> ), and fill factor (FF).