The current coordination between the transmission system operator (TSO) and the distribution system operator (DSO) is changing mainly due to the continuous integration of distributed energy resources (DER) in the distribution system. The DER technologies are able to provide reactive power services helping the DSOs and TSOs in the network operation. This paper follows this trend by proposing a methodology for the reactive power management by the DSO under renewable energy sources (RES) forecast uncertainty, allowing the DSO to coordinate and supply reactive power services to the TSO. The proposed methodology entails the use of a stochastic AC-OPF, ensuring reliable solutions for the DSO. RES forecast uncertainty is modeled by a set of probabilistic spatiotemporal trajectories. A 37-bus distribution grid considering realistic generation and consumption data is used to validate the proposed methodology. An important conclusion is that the methodology allows the DSO to leverage the DER full capabilities to provide a new service to the TSO.

传输系统运营商（TSO）与配电系统运营商（DSO）之间当前的协调正在发生变化，这主要是由于配电系统中分布式能源（DER）的持续集成。DER技术能够提供无功功率服务，从而帮助DSO和TSO进行网络运营。本文通过遵循这种趋势，提出了DSO在可再生能源（RES）预测不确定性下由DSO进行无功功率管理的方法，从而允许DSO协调和向TSO提供无功功率服务。建议的方法需要使用随机AC-OPF，以确保DSO的可靠解决方案。RES预测不确定性是通过一组概率时空轨迹建模的。考虑实际发电量和消耗量数据的37总线配电网用于验证所提出的方法。一个重要的结论是，该方法允许DSO利用DER的全部功能为TSO提供新的服务。