Design and Implementation of a DC Microgrid Control System for Offshore Platforms with Wind-Solar-Storage Integration

This paper studies the design and implementat ion method of a wind-solar-storage DC microgrid system to provide long-term and reliable green power supply for offs hore platforms. Based on the actual offshore meteorological conditions, the paper establishes the mathematical models of the wind-solar-storage units and power converters, and ana lyzes the output characteristics of the new energy units acc ording to the offshore meteorological information. Then, the control strategy of the wind-solar $\mathbf{r}$-storage DC microgrid $\mathbf{f}$ or offshore platforms is studied. The energy storage unit is used as the grid-forming power source to stabilize the bus voltage and balance the system power. The maximum powe r point tracking (MPPT) control is adopted for the wind a nd solar power generation units to achieve the grid-followin g characteristics of the power sources, and the field-oriented control (FOC) method is used to control the wind turbine speed. Finally, the capacity matching relationship of the syst em is determined, and the simulation and experimental plat forms are built. Experiments under all operating conditions of the system are carried out, including the stability of the bus voltage, the output capacity of the wind and solar new energy generation units, the charging and discharging char acteristics of the energy storage unit, and the dynamic resp onse ability of the system under the scenarios of sudden loa d changes and new energy fluctuations. The experimental re sults show that the transient response of the system bus vol tage has good fast response and recovery characteristics. W hen the new energy has intermittent power generation and the load changes, the system bus voltage can maintain g ood stability.