With the increasing number of large-scale renewable energy stations, modelling each converter in the station will result in excessive computation, which is not conducive to the stability analysis of large-scale renewable energy stations. The coherent equivalence method is a reduced-order modelling method that retains the structure of the system components, and the equivalent model still has a clear physical meaning, so the coherent equivalence method can be used to simplify the modelling. In this paper, we first give an overview of the equivalent aggregated modelling of grid-following converters and grid-forming converters in multi-converter systems, and also introduce the selection of coherency criterion and the calculation of aggregation parameters. It then reviews the aggregation methods for wind farms in practical applications, including the equivalence of wind speeds, the subgrouping of wind farms, and points out the equivalence modelling methods under low voltage ride through (LVRT). Finally, the difficulties faced by the existing studies on isotropic modelling are discussed, and isotropic modelling methods applicable to transient synchronization stability analysis are explored, and the future research direction is looked forward to.