Multi-timescale risk scheduling for transmission and distribution networks for highly proportional distributed energy access

Abstract

With the incorporation of more renewable energy sources, distribution networks are shifting from passive to active. The interconnection of the transmission and distribution networks will increase and the tidal currents will become bidirectional, affecting the stable operation of the transmission and distribution networks. This paper proposes a multi-timescale risk dispatch study for transmission and distribution networks that have a high proportion of distributed energy access to meet the rising demand for coupling between the two types of networks. First, a day-ahead scheduling model that takes into account various operational risks is developed with the goal of minimizing total operating costs, and it optimizes the source network load and storage of multiple adjustable resources of the transmission network and distribution network jointly under the risk limit constraint. Second, an intraday scheduling model is built with the goal of minimizing the risk cost of the transmission network and distribution network, and the day-ahead scheduling plan is modified by considering the day-ahead forecast error and the different operational risks of the transmission network and distribution network. Finally, the effectiveness of the proposed multi-time-scale risk dispatch model is verified through the analysis of arithmetic cases, and it is proved that the model can enable the interaction and coordination between transmission and distribution networks as well as the synergistic optimization of operating costs and operating risks.