Power Factor Correction for DC-Powered Buildings Using an Isolated AC-DC Interlinking Converter: Experimental Validation and Comparative Analysis

In conventional ac systems, power factor correction is usually applied to medium and high-power loads, but this can reduce overall system efficiency in residential and commercial installations, where most loads are low power. Unlike ac systems, dc systems do not suffer from power factor or reactive power issues, as they process only active power, resulting in energy savings. However, to interface with the ac grid, an ac-dc interlinking converter is still needed to form a stable dc distribution bus inside buildings. In this paper, a power factor correction approach for dc-powered buildings using an isolated ac-dc interlinking converter is presented. The converter is designed to ensure a high-power factor at the ac grid side while providing a stable dc supply for loads inside building. The paper compares the performance of this dc-based electrical installation with that of conventional ac systems without power factor correction for low-power loads, highlighting the advantages of dc distribution, such as improved energy efficiency. To experimental evaluate the operation of the interlinking converter, a 5-kW prototype was built and laboratory tested, demonstrating its capability to maintain high power factor, provide a stable dc output, and enhance overall system efficiency.