short-circuit current constraint, wind farm equivalence, line switching, power grid planning, unit startup and shutdown status, Electricity, QC501-721, Production of electric energy or power. Powerplants. Central stations, TK1001-1841

In order to address the new challenges brought by the large-scale integration of new energy into the power system represented by wind power, a wind power grid expansion planning model considering line optimization, switching, and current limiting is proposed. First of all, from the perspective of conventional thermal power unit startup and shutdown caused by system load change, the short circuit current constraint in typical scenarios is converted into the constraint under the corresponding unit startup and shutdown status. The equivalent expression of wind farm is studied by the structural equivalence of wind farm’s power collection system, and the short circuit current constraint considering the wind power connection is introduced. Secondly, by determining the overall idea of power grid expansion planning and taking the minimum total investment as the objective function, the mixed integer linear programming model of power grid planning is established and solved that comprehensively considers the energy storage, demand-side response and short-circuit current constraints. Finally, taking IEEE-RTS 24-node system as an example, the effectiveness of the proposed method is verified by setting different cases for comparative analysis.