Published Paper Details:

Industrial facilities are characterized by a high density of inductive loads, such as induction motors and transformers, which draw lagging reactive power. This results in a low power factor (PF), leading to increased apparent power, elevated line losses, poor voltage regulation, and reduced system capacity. Utility providers impose financial penalties on consumers whose PF falls below a stipulated threshold (typically 0.90-0.95). This paper presents the design, implementation, and validation of a microcontroller-based Automatic Power Factor Correction (APFC) unit to mitigate these penalties. The system continuously monitors the load PF using zero-crossing detection of voltage and current waveforms. An AVR or 8051 microcontroller processes these signals, calculates the instantaneous PF, and automatically engages optimal combinations of capacitor banks via relay drivers to inject leading reactive power, thereby bringing the PF close to unity. The hardware design incorporates a single-phase power supply, potential and current transformers for measurement, and a capacitor bank for compensation. Experimental results demonstrate the system's efficacy in improving PF from values as low as 0.67 to above 0.95, effectively avoiding penalty charges. The system offers a cost-effective, reliable, and automated solution for enhancing energy efficiency in industrial power consumption.