Design and implementation of a portable low-cost internet-enabled <i>I-V</i> curve tracer utilizing Ćuk Converter

This work presents the development of an internet-enabled current-voltage (I-V) curve tracer prototype circuit. With an emphasis on cost-effectiveness and data accessibility, the prototype was constructed utilizing Raspberry Pi 4 as the data acquisition board equipped with a TFT display and webserver connectivity. The prototype was designed to handle up to 60V open-circuit voltage, 10A short-circuit current and a maximum power point of 250W. The measured data is processed programmatically with a filtering algorithm to smoothen the curve by removing outlier values measured due to noise. Further refinement was achieved by averaging multiple data points recorded at each step of a single duty cycle change. The prototype was tested on three commercially available PV modules through Chroma 62100H-600HS Solar Array Simulator. The proposed device achieved an overall average RMSE and RRMSE of 0.2848A and 6.4985% respectively. By combining linear duty cycle with linear gain changes across different regions of the I-V curve, a more even distribution of data points was achieved, resulting in a total scan time of 6.8 seconds. While sufficient for less accuracy-intensive tasks, the current prototype is not ideal for research-grade applications. It is expected that with the use of a dedicated printed circuit board (PCB), for reduced noise and enhanced signal integrity, higher accuracy could be achieved. Nonetheless, this project successfully demonstrated the feasibility of incorporating internet connectivity for remote monitoring of PV module status.