Wind Farm Doubly-Fed Induction Generator Simulation

In wind power generation systems, the Doubly-Fed Induction Generator (DFIG) has become the mainstream model due to its excellent variable-speed constant-frequency characteristics. Simulation modeling serves as a crucial method for analyzing its dynamic behavior and grid-connection characteristics, with the core components divided into the following sections: DFIG Modeling Dynamic equations incorporating the electromagnetic relationships of stator and rotor windings must be established, with special attention to the impact of slip variation on the magnetic field. Using the dq-coordinate system simplifies the coupling issues of three-phase AC quantities, while also requiring the integration of control strategy models for the rotor-side converter. Implementation typically involves solving voltage equations in synchronous reference frame using Park transformations. Wind Turbine Integration Coupling aerodynamic models with generator models includes wind rotor power capture characteristics, pitch angle control logic, and torsional vibration models of the drive train. Particular attention should be paid to the dynamic transfer process of wind speed randomness and mechanical inertia. Code implementation often requires real-time calculation of turbine power coefficient curves and shaft dynamics differential equations. Grid Interaction Simulation Focus on verifying Low Voltage Ride-Through (LVRT) capability, requiring simulation of crowbar circuit protection activation during grid voltage dips and transient current suppression strategies of converters during faults. This involves implementing protection logic blocks and current limiting algorithms in the control system. Simulation Tool Selection Commonly use MATLAB/Simulink to build modular models, or employ PSCAD for more precise electromagnetic transient simulations. It's recommended to simplify mechanical components first, then gradually add converter switching details to improve efficiency. Key functions include power system blockset components and switching device modeling libraries. This simulation approach enables optimization of unit control parameters, validation of fault protection strategies, and provides fundamental models for wind farm cluster stability research. The implementation typically involves iterative parameter tuning through scripted simulation batches and performance analysis using FFT tools for harmonic assessment.