Aggregation frequency response modeling with applications to East China power grid

In the receiving-end power grid, the proportion of external power supplies and large-scale renewable power generations has increased rapidly, which not only increases the unbalanced power impact of the system, but also weakens the frequency support capability of the system. Therefore, frequency security becomes a bottleneck of the receiving-end power grid, and system frequency response modeling becomes a key concern. In this paper, an aggregation modeling method is presented to build the system frequency response model (SFR). Two types of the SFR model structures are proposed. The first one considers the dynamics of the governors and prime movers of both the thermal and hydro units, which is suitable for the simulation and analysis of the system frequency behaviour following small power disturbances. The second one additionally considers the boiler dynamics of the thermal units, which is suitable for the simulation following large power disturbances. The parameter aggregation method for the SFR model are also proposed. The aggregation SFR model is built based on the detailed model of the east China power grid. The results show that the proposed method can achieve satisfactory performance owing to its accuracy and efficiency.