Impact analysis of uncoordinated electric ferry charging on distribution network

Abstract

The maritime sector significantly contributes to greenhouse gas emissions, and implementing electric marine vessels can mitigate this emission. Replacing conventional ferries with EFs (Electric Ferries) necessitates dockyard charging stations, making it crucial to analyze the EF's charging impacts on the shore-side distribution network. This research examines the potential effects of uncoordinated EF charging on a regional Australian distribution network. Using OpenDSS (Open Distribution System Simulator) software, power flow impact analysis is conducted on a selected simulated distribution network, integrating BESSs (Battery Energy Storage Systems) as representation of proposed charging stations. The load demand is increased to 50 % and 80 %, given the actual demand is 15 % of the transformers’ capacities. The power flow results without BESSs serve as the base case. In uncoordinated mode, bus voltages decrease by 1 %-3 %, and load currents increase by 2 %-3.5 % compared to the base case. Additionally, lines and transformers near BESS-connected buses see a 1 % rise in power flow with increased total power consumption and loss. THD (Total Harmonic Distortion) and TDD (Total Demand Distortion) are over 5 % and 18 % in uncoordinated charging, which exceeds harmonics limits according to IEEE 519–2022 standards. These results may provide valuable insights for installing EF charging stations in distribution networks.

Keywords

• Electric ferry
• BESS
• Uncoordinated mode, Distribution network
• OpenDSS
• Harmonics analysis