Intelligent Filtering Solutions for Improving Power Quality in Marine Shipboard Systems

With the ever-increasing penetration of power-electronic interface-based sources and loads, power quality issues have emerged as an immediate concern in both conventional and customized grids. Active filters connected in shunt across the harmonic loads have emerged as the most optimal solution in conventional grids. However, its deployment in a large network with distributed harmonic loads will result in higher costs. Additionally, placing filters at low-voltage nodes will result in higher current demands, which results in lower operating efficiency and higher cost. To address these concerns, this paper presents a novel filtering solution to optimally and scarcely place active filters. In this control algorithm, the given system is divided into subsystems, and depending upon the requirement, the control algorithm prioritizes placing the filters on each voltage node and selecting the nodes yielding a better harmonic profile, efficiency, and cost. To establish and validate the control algorithm, a detailed modeling study, and THD profiling of a National Security Multi-Mission Vessels’ (NSMV) (an upcoming training and disaster relief vessel at Texas A&M University) 43-node distribution system are presented as benchmarking data in this paper. To meet the mandatory THD requirement, the control algorithm places active filters at each node until the THD requirement is met. Detailed simulation results showing the performance with and without the active filter are presented.