Modelling and Impedance Characterisation of Doubly-fed Wind Turbines

The interactions between various factors and the impedance characteristics of DFIG wind turbines is meaningful. This paper focuses on the DQ impedance model of the Doubly-fed Induction Generator wind turbine (DFIG), analyzing multi-factor effects on impedance characteristics. Firstly, a small-signal model of DFIG considering DC voltage outer loop is established. Then, to perform frequency sweep on DFIG to obtain impedance external characteristic curves and compare the impedance curves under various influencing factors such as different control structures, control parameters, and stable operating points. Additionally, semi-physical frequency sweep on the DFIG wind turbine using RTDS device is constructed.