Electromagnetic transient modelling approach for the Doubly-fed Induction Generator

Electromagnetic transient simulation software such as PSCAD/EMTDC encapsulates the asynchronous motor digitally, and although the model is highly accurate, the user does not have access to the internal structure of the motor, which limits the simulation design and optimization of wind turbines for acceleration. To address this problem, a structured modelling approach for the Doubly-fed Induction Generator(DFIG) is proposed. Based on the Electro-Magnetic Transient Programs (EMTP), the mathematical equations of the generator are discretized and the direct machine-network interface between the generator and the external electrical network is obtained by inverse transformation of the coordinates of the stator-rotor system. Based on the PSCAD/EMTDC environment, an equivalent model of the Doubly-fed Induction Generator is developed and compared with the library model to verify the correctness of the constructed equivalent model. The proposed DFIG equivalent modelling method can provide a model basis for the design and simulation acceleration of electromagnetic transient models for large-scale wind turbines.