Modelling and Control of Wind-PV-SOFC-Battery Based DC Microgrid

Modelling and control for a DC microgrid are key technologies to ensure the reliability and stability of the DC microgrid power supply. In particular, distributed renewable energy generation is known to be unstable. There is no support from main AC network when operating in island mode, which would easily cause power imbalance in the network, and eventually leads to DC bus voltage instability and even system crash. In recent years, high temperature solid oxide fuel cells have achieved great development and are expected to be used as a flexible power source for distributed microgrids. Therefore, this paper presents a model for DC microgrids based on wind-PV-SOFC-battery. Within the DC microgrid model, a wind power generation unit, a photovoltaic power generation unit, a high temperature fuel cell, a battery unit and a load unit are established to control the operation of DC microgrid and to manage the energy of battery. The feasibility and effectiveness of this method are verified via simulation under various modes.