Investigating The Combined Effect of Reconductoring and DG Placement on the Load Hosting Capacity of Radial Distribution Networks

Abstract

The increasing penetration of distributed generation (DG) and the need to accommodate load growth have made load hosting capacity (LHC) a key issue in radial distribution network planning; and feeder reconductoring remains a viable means of modifying network impedance and efficiency. However, the combined influence of reconductoring and DG placement on LHC is not fully explored, particularly under constraints such as voltage rise, reverse power flow, and thermal limits. This study was conducted using the IEEE 33-bus radial feeder, where a 2.5 MW DG operating at unity power factor was sequentially placed across all eligible buses under five distinct reconductoring instances. LHC was determined by incrementally increasing system load using quasi-static backward–forward sweep power flow analysis until constraint are violated, Statistical validation using the Kruskal–Wallis H test was used to assess the significance of the observed changes. The results showed that LHC was governed by a nontrivial interaction between conductor impedance and DG location. For instance, low, uniform impedance profiles deferred upstream constraint violations by maximizing LHC (up to 8.65 MW) when the DG was placed at the terminal bus. Further, high trunk impedance reduced LHC and shifted optimal DG placement toward intermediate or near-source buses to prevent voltage dip in weaker branches. Additionally, when strategically installed feeder-wide, highly resistive conductors with improved X/R ratios partially restored terminal DG placement optimality with moderate LHC. The statistical results (H = 73.03, p = 5.20 × 10⁻¹⁵) confirmed that these variations are significant and nonrandom, highlighting the importance of coordinated co-optimization of reconductoring and DG placement for maximizing LHC and enabling proactive feeder planning.