Analysis of Electro-Magnetic Interference on Underground Cable According to Grounding Methods in AC/DC Hybrid Distribution Networks

Due to the proportion of renewable energy increase, DC systems are in demand and the study on AC/DC Hybrid system is ongoing. The current AC distribution system is characterized by a passive, unidirectional flow of power, which limits power control and causes power loss in AC/DC conversion for DC demands. The AC/DC Hybrid distribution system improves system operational efficiency by integrating DC systems into existing AC system, expanding the capacity for renewable energy integration, and reducing conversion losses from AC to DC. However, depending on the line configuration, AC/DC cables may be positioned adjacently, potentially causing electro-magnetic interference (EMI) between them. This paper proposes the best grounding methods of underground cable which is appropriate to the AC/DC Hybrid distribution system. The validation of the grounding methods of underground cable was performed by Electro-Magnetic Transients Program (EMTP) ATP-Draw.