A Stability Analysis of Small Disturbances in Grid-Connected Doubly-Fed Wind Farms with DC Voltage Time Scales
The broadband oscillation instability caused by grid-connected wind farms seriously affects the safe and stable operation of new energy power systems.In this paper,to address the small disturbance stability problem of grid-connected doubly-fed wind farm DC voltage time scale,firstly,a full-order linearised model of the doubly-fed wind farm is derived,based on which an aggregation model of the grid-connected doubly-fed wind farm with rotor-side converter power outer-loop control and grid-side converter DC voltage outer-loop control is constructed,and then a small disturbance stability criterion of the grid-connected doubly-fed wind farm is derived based on the Rausch-Hurwitz theorem.Based on the small disturbance stability criterion,it is revealed how the AC grid strength,wind turbine active power,doubly-fed turbine control parameters and wind farm network structure jointly affect the small disturbance stability of the system.Finally,a grid-connected doubly-fed wind farm with 15 doubly-fed turbines is used as an example to verify the correctness and effectiveness of the theoretical derivation presented in this paper.
grid-connected doubly-fed wind farmssmall disturbance stabilitylinearised modelDC voltage time scalenetwork structurestability criterion
万方数据
维普
