Long-term wind accommodation of interconnected power grids via HVDC tie-line based on aggregate unit model

In the interconnected power grids, the wind energy can be accommodated in the wider area by optimizing the tie line power flows and coordinating the multi-area generation resources. Therefore, a sequential simulation method considering the flexible operation of high voltage direct current (HVDC) tie lines is presented in the paper to analyze the wind accommodation in the long-term horizon. To speed the computation for long-term simulation, the aggregate unit model is considered to reduce the number of integer variables by clustering a large number of individual units into a few of unit groups. In addition, a rolling calculation strategy is adopted for the simulation of a year. In the end, a case study is conducted to show the feasibility and effectiveness of the proposed method.