Finite state based power balance validation of a marine ferry microgrid under various operating conditions

With ever fluctuating marine loads, the need for optimised, less complex Power Management Scheme (PMS) for ferry microgrid becomes crucial. In this work, a Ro-Ro ferry based microgrid is presumed encompassing Diesel Generators (DGs), Solar PV and battery as the power sources to cater the fluctuating propulsion and constant service loads. The system has a hybrid AC-DC bus, interlinked through a bidirectional, voltage sourced, Interlinking Converter (IC) exerting uninterrupted bidirectional power transfer, load compensation and unity power factor operation through Instantaneous Power Theory (IPT). The entire system is modelled and state based PMS is framed for all possible conditions with two states, five sub states and fourteen cases so as to reduce the carbon footprint through the maximum usage of renewables. The entire system performance for different sea states (calm, moderate and turbulent) along with the response of state based PMS for different scenarios claims to be the main merit of this work. The proposed power management, notably reduces the DG usage by 40 – 60 % and achieves upto 74 % of renewable energy penetration during calm sea states, resulting in an estimated 40 % reduction in carbon footprint. A Hardware-in-the-Loop (HiL) configuration employing OPAL-RT OP4512 real-time simulator encompassing the microgrid and dSPACE Scalexio for real-time controller implementation is used to validate the state based PMS. With different mode changes, the steady state is observed to reach within 500 ms exhibiting steady power flow and good control responsiveness under a range of load and sea condition. The HiL results indicate the effective achievement of decarbonization in maritime microgrids in a scalable and effective manner.