Application of Structured Control Logic of DFIG-Based Wind Turbines in Converter Controllers

As the proportion of renewable energy connected to the grid continues to increase, doubly fed induction generators (DFIGs) have become the mainstream model in wind farms due to their excellent variable-speed constant-frequency control characteristics. However, current DFIG control systems still suffer from issues such as inconsistent model structures and closed control logic, leading to a lack of standardized verification methods for fault ride-through capabilities under complex grid disturbances. This limits the development and engineering application of control strategies. To address these issues, this paper proposes a standardized hierarchical control logic tailored for doubly fed wind power converters. First, mathematical control models for the machine-side converter and grid-side converter were established. A full-time-scale control strategy suitable for both low-voltage ride-through and high-voltage ride-through was designed, covering the entire process from pre-fault steady-state, dynamic support during faults, to post-fault recovery. Additionally, a hardware-in-the-loop experimental system was constructed using the RTLAB real-time simulation platform and a DSP controller to validate the effectiveness and consistency of the structured model and control logic under various operating conditions. The research results provide a theoretical foundation and experimental support for the standardized modeling and engineering implementation of control strategies for doubly fed wind turbine generators.