Sustainable Power-Quality Enhancement and Loss Reduction in Radial Distribution Networks Using a DCM Cuk-Based Power Factor Correction Scheme

Power-quality degradation caused by nonlinear loads remains a critical challenge in sustainable low-voltage distribution systems, as it increases harmonic distortion, reactive power circulation, feeder losses, and thermal stress in network assets. This paper evaluates a discontinuous-conduction-mode (DCM) Cuk-based power factor correction (PFC) scheme integrated with a silicon-controlled rectifier (SCR) stage to improve power quality in a radial distribution feeder. The IEEE 13-bus distribution test system is used as the benchmark network, with the nonlinear load connected at node 634, supplied through a 4.16/0.48 kV transformer. Two operating scenarios are compared, an uncompensated case and a compensated case, using the SCR–Cuk PFC structure. The assessment considers source-side voltage and current waveforms, power factor, total harmonic distortion (THD), voltage deviation, nodal harmonic propagation, active and reactive power flows, and line losses. The results show that the proposed scheme increases the source-side power factor from 0.431 to 0.99 and reduces the source current THD from 16.31% to 1.10%, meeting the source-side 5% harmonic reference level used in this study. At the network level, the THD at node 634 decreases from 17.12% to 6.23%, while the main affected feeders show relevant reductions in active and reactive losses. These findings indicate that localized active PFC can support more sustainable distribution system operation by improving power quality and reducing losses. However, feeder-wide harmonic compliance may require distributed compensation at additional harmonic-sensitive nodes.