Development of a Single-Phase Power Analyzer on an Embedded System

Abstract

The proliferation of non-linear loads in modern electrical systems has intensified the degradation of Power Quality (PQ), leading to technical and economic impacts ranging from equipment overheating to significant financial losses. Given the need for continuous monitoring in compliance with current regulations, such as ANEEL’s PRODIST Module 8, this work details the development of a low-cost, single-phase power analyzer prototype. The system employs a potential transformer for voltage measurement and a Rogowski coil for current, chosen for its linearity and lack of saturation. The signals were processed by an STM32 microcontroller, which implements real-time algorithms to calculate parameters such as RMS voltage and current, frequency, active, apparent, and reactive power, and power factor. The experimental validation of the prototype was performed through tests with resistive and inductive load banks, comparing the results with a high-precision Tektronix PA4000 power analyzer. The results showed satisfactory performance, with measurement errors mostly below 3% for the main parameters under nominal conditions, thus validating the prototype’s feasibility as a practical tool for diagnosing disturbances and analyzing energy efficiency in low-voltage installations.