Management and Distribution Strategies for Dynamic Power in a Ship’s Micro-Grid System Based on Photovoltaic Cell, Diesel Generator, and Lithium Battery

Abstract

Combining new energy technology with electric propulsion technology is an effective way to decrease the pollution of water resources caused by cruise ships. This study examines the stable parallel operation of a ship’s micro-grid system through a dynamic power management strategy involving a step change in load. With cruise ships in mind, we construct a micro-grid system consisting of photovoltaics (PV), a diesel generator (DG), and a lithium battery and establish a corresponding simulation model. We then analyze the system’s operating characteristics under different working conditions and present the mechanisms that influence the power quality of the ship’s micro-grid system. Based on an analysis of the power distribution requirements under different working conditions, we design a power allocation strategy for the micro-grid system. We then propose an optimization allocation strategy for dynamic power based on fuzzy control and a load current feed-forward method, and finally, we simulate the whole system. Through this study we prove that the proposed power management strategy not only verifies the feasibility and correctness of the ship’s micro-grid structure and control strategy, but also greatly improves the reliability and stability of the ship’s operation.