ISOS-SAB DC/DC Converter for Large-Capacity Offshore Wind Turbine

• Published in: Energies (Basel) Vol. 17; no. 20; p. 5071
• Main Authors: Cai, Xipeng, Liu, Yixin, Zhu, Yihua, Zhou, Yanbing, Luo, Chao, Liu, Qihui
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 01-10-2024
• Subjects: Air-turbines; Alternative energy sources; Bridges; Buildings and facilities; combinational control; Comparative analysis; DC/DC converter; Electric current converters; Electric transformers; full DC offshore wind farm; input series output series; Offshore; single active bridge topology; Turbines; Wind farms; Wind power; China
• ISSN: 1996-1073; 1996-1073
• DOI: 10.3390/en17205071

This study offers a modular isolated grid-connected DC/DC medium-voltage DC aggregation converter to support offshore full DC wind farms’ need for lightweight and highly efficient power aggregation and transmission. The converter can simultaneously have a smaller transformer size and lower switching frequency during operation through the dual-voltage stabilization three-loop control strategy and phase-shift modulation strategy, which greatly reduces the space occupied by the converter and lowers the switching loss, Additionally, the use of a two-level structure at a lower switching frequency has lower loss, which effectively reduces the cost of the power device compared with the commonly used three-level converter. The input series output series connection between the converter sub-modules effectively lowers the voltage stress on each power switching device and facilitates expansion into a multi-module structure, expanding its application in high-voltage and large-capacity environments. This study analyzes the two working modes of the DC/DC converter and its control approach, in addition to providing a detailed introduction to the application scenarios of this converter. Ultimately, the efficacy and practicability of the suggested topology and control scheme are confirmed by simulations and experiments.