International Journal of Science, Engineering and TechnologyAuthors: Aarnav Rao, Antara Prabhune, Rajdeep Choudhuri, Dr.Thamilmaran
Abstract: This paper presents the design of a low-cost, PC-based power quality analyzer intended for educational experimentation with low-voltage AC signals. The prototype combines an ESP32 microcontroller, LM358-based analog signal conditioning, a series RC test load, a low-side shunt resistor for current sensing, USB serial data transfer, and a Python analysis application. The voltage channel scales a nominal 10 V peak-to-peak, 50 Hz source using an inverting amplifier, while the current channel measures the voltage developed across a 1 Ω shunt placed in series with a 220 Ω resistor and a 10 µF capacitor. The software is designed to estimate RMS voltage and current, frequency, real and apparent power, power factor, phase difference, and waveform spectra. Analytical calculations provide a reference operating point for validating the prototype. At the time of writing, the current-conditioning output has exhibited an approximately flat response and the complete measurement chain has not yet been calibrated; consequently, no unverified experimental performance is claimed. The paper documents the architecture, circuit design, acquisition method, analysis procedure, preliminary calculations, and validation plan.
