Screening method for subsynchronous oscillation risks in large-scale wind farm gathering area

Abstract

The invention belongs to the technical field of subsynchronous oscillation evaluation of wind farms, and particularly relates to a screening method for subsynchronous oscillation risks in a large-scale wind farm gathering area. The screening method comprises the steps of determining grid connection points of the wind farms in the wind farm gathering area, and defining the first section point of anoutgoing line in the gathering area as a gathering station; calculating the grid connection point short circuit capacity and the single wind field capacity of individual wind farms; calculating the overall short circuit capacity of the gathering station; calculating the overall fan capacity of the gathering station; calculating the short-circuit ratio of the gathering station; judging a subsynchronous oscillation risk region according to a calculation result of the short-circuit ratio of the gathering station. The screening method has the advantages that capacity differences between the windfarms in the gathering area, as well as influences of an internal grid structure of the gathering area on the short-circuit ratio of the gathering station can be considered, thereby being applicable to subsynchronous oscillation risk screening of the large-scale wind farm gathering area.

Description

Technical field [0001] The invention belongs to the technical field of subsynchronous oscillation assessment of wind farms, and in particular relates to a method for screening subsynchronous oscillation risks in a large-scale wind farm collection area. Background technique [0002] In recent years, as the installed capacity of new energy power generation has increased year by year, a large number of power electronic devices have been connected to the power system, which has introduced a series of new subsynchronous oscillation problems, especially the subsynchronous oscillation caused by the interaction between wind farms and the power grid. Due to the characteristics of my country's energy and load distribution, long-distance, inter-provincial and inter-regional power transmission has become one of the important challenges facing my country's transmission grid, and the short-circuit ratio of grid-connected points decreases with the increase of the grid-connected capacity of wind ...

AI Technical Summary

Problems solved by technology

If the existing short-circuit ratio calculation method is applied to a large-scale wind farm collection area, all wind farms in the collection area need to be regarded as being directly connected to the collection station, so it cannot reflect the difference in capacity of each wind farm in the area and the internal capacity of the collection area. The impact of the network structure on the strength of the AC system of the junction station caused a large deviation in the calculation results of the short-circuit ratio, which seriously affected the accuracy of subsynchronous oscillation risk screening

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