Interconnection of a 13.2 kV Primary Distribution Feeder to Reduce Loading at Substation 5004

Abstract

This project evaluated and implemented a primary feeder interconnection at 13.2 kV to reduce the electrical loading of Substation 5004 Ramblas in Ponce, Puerto Rico. Operational studies indicated that the substation was operating at approximately 96% of its nominal capacity, exceeding recommended operating limits and increasing the risk of transformer degradation and service interruptions. A feeder interconnection was designed to transfer part of the load to an adjacent distribution feeder with available capacity. Load flow simulations and distribution design validation were performed using PoleForeman and ArcGIS system data to verify the feasibility of the proposed configuration. The results demonstrated a reduction of approximately 4 MVA of load, equivalent to a 19% decrease in transformer loading, lowering the operating level from 96% to approximately 77%. The project also enabled the interconnection of a new 1 MVA commercial load while maintaining acceptable operating margins. The final design complied with distribution engineering standards, operational requirements, and system resilience considerations. The project was implemented within the existing right-of-way, avoiding legal acquisition processes and remaining within the established project budget of $500,000, with a final cost of $474,743.88. The feeder interconnection improved distribution system reliability, enhanced load management capability, and extended the operational life of the substation transformer. Key Terms - Distribution Substation, Distribution System Reliability, Load Management,Primary Feeder Interconnection.