Three-phase Three-level Converter and Its Control Strategy for Grid-connected High-capacity Wind Power Generation

When compared to AC pooling, the use of DC pooling in offshore wind farms can greatly increase transmission efficiency while lowering the cost required to build and run the wind farms. Studying the topology of the main component of the DC convergence DC/DC converter and choosing the best modulation and control strategy are particularly crucial. In this study, a three-phase, three-level DC/DC converter is chosen as the research object. A phase-shifted pulse width modulation (PSPWM) strategy is suggested, and a voltage-current double-closed-loop PI control strategy is adopted to ensure the input voltage's stability. The parameters of this converter are also corrected and optimized. The converter has both fault isolation functions and is appropriate for grid-connected situations involving a lot of power. It also has a substantial suppressive effect on the phenomenon of huge input voltage variations in offshore wind farms, which makes it possible to operate at high voltage gains. The success of the topology and control method is then confirmed using a simulation model created in Simulink and a real-time simulation platform.