Robust Two-Stage Regional-District Scheduling of Multi-carrier Energy Systems With a Large Penetration of Wind Power

This paper proposes a robust day-ahead scheduling method for a multi-carrier energy system (MES), which would enhance the flexibility of power systems with a large sum of variable wind power. We build an MES model and propose an optimal MES schedule which helps MES reduce wind power curtailment in power systems. At first, electricity and natural gas networks are coordinated at the transmission (regional) level for accommodating the large penetration of wind power in regional MES. The distribution (district) level MES coordinates energy conversion and storage to jointly supply the electricity, natural gas, and heat loads. The transmission level MES is modeled using detailed network equations while the distribution level MES is modeled as a device with multiple input/output ports using the linear branch-flow-based energy hub model. A two-stage robust model is established to consider the variability of wind power at the two MES levels. The proposed problem is solved by a nested column-and-constraint (C&CG) generation method. The first-stage problem which schedules the hourly unit commitment is solved in the outer loop, while the inner loop solves the second-stage problem to realize the worst scenario. Several acceleration strategies are utilized to enhance the computational performance of the nested C&CG. Numerical results offered for a 6-bus 3-node system and a modified IEEE 118-bus 10-node system show the effectiveness of the proposed MES model and solution technique for enhancing the power system flexibility.