Unlike conventional power plants, wind farms typically consist of hundreds of wind generators and collector systems with arbitrary topologies. The numerous devices involved increase modeling complexity and computational burden. This chapter proposes a vector-variable-based method for dynamic modeling of large-scale wind farms, considering the dynamics of the collector system. By using vector variables, the modeling method simplifies the complex wind farm into a model consisting of two typical sub-modules: the wind generator module and the collector system module. These sub-modules can represent any number of wind generators and any collection system topology while considering dynamics, with excellent scalability. The accuracy and high simulation efficiency of the established model are validated against an electromagnetic model. Furthermore, a detailed wind farm containing twenty-five wind generators is constructed using the proposed method. Compared with the aggregation model, the results show that the established model accurately reflects wind farm stability. Additionally, comparison with a model that neglects collector system dynamics reveals that ignoring these dynamics can lead to significant errors and misjudgments of instability modes during sub-synchronous mode analysis.