Regulation Capacity Margin Evaluation of Power Systems Considering Multiple Flexible Resources

With a large number of renewable energy sources connected to the grid, the aim is to achieve carbon neutrality in the mid-century. However, the increasing renewable energy penetration of power system introduces fluctuation and uncertainty, which jeopardize its safe and stable operation. Additionally, the inflexible nature of traditional thermal power units leads to insufficient supply and absorption difficulties. Consequently, there is an urgent need to utilize more flexible resources and evaluate the power system's regulation capacity margin. Firstly, we modeled the flexibility resources from the storage side and load side of the power system, where the storage side mainly includes pumped storage units and storage batteries; the load side employs load aggregators, including temperature-controlled loads (TCL) and electric vehicles (EVs) clusters. The stochastic production simulation method was employed to sample uncertainties related to new energy units and load fluctuations while retaining time-series information. This compensated for the traditional method's limitations in dynamically and accurately assessing the level of new energy consumption at each specific time. Subsequently, a quantitative evaluation metric system for power system regulation capacity is developed, considering both overall power system regulation capacity and contribution of individual flexibility resources to regulation capacity. Finally, the proposed method is based on the modified RTS-79 bus system and the experimental results demonstrates the effectiveness.