Online Monitoring System for Harmonics with Passive Filter on A 110 KW Three-Phase Inverter

This study aims to design and implement a real-time power quality monitoring system and mitigate harmonic distortion in a 110 kW three-phase inverter using a passive harmonic filter. The monitoring system was developed based on the Internet of Things (IoT) using an ESP8266 microcontroller, enabling real-time data logging and visualization of electrical parameters—such as voltage, current, THD, and power factor—through Google Sheets and the Blynk application. Initial measurements showed that the 5th-order current harmonic distortion reached 47.78%, exceeding the maximum threshold set by the IEEE 519-1992 standard. To address this, a single-tuned passive harmonic filter was designed based on IEEE 1531-2003 standards, successfully reducing the Individual Harmonic Distortion (IHD) to 14.3% and improving the power factor from 0.76 to 0.85. The filter was built with key components including a 169.45 µF capacitor and a 26.5 mH inductor. This reduction in harmonics not only improves system efficiency but also extends the lifespan of electrical equipment. The designed monitoring system proved effective in detecting changes in power quality responsively, supporting technical decision-making and enabling timely corrective actions. Given the results, this system can serve as a model for application in other industrial installations with high non-linear loads. Future development is recommended to include additional environmental parameters and integration with interactive dashboards to enhance the quality of monitoring and analysis.