Optimal Scheduling for Networked Microgrids Considering Back-to-Back MVDC Systems

Abstract

Networked microgrids (MGs) have emerged as a favored and promising scheme to facilitate the integration of distributed energy resources and enhance the resiliency of power support. To advance the flexible operation of distribution systems, this paper proposes an optimal scheduling model for networked MGs, embedding three innovative medium-voltage direct current (MVDC) technologies with voltage source converters, namely two-terminal back-to-back MVDC systems (BMSs), three-terminal BMSs, and multi-terminal BMSs. Compared to traditional MVDC systems, these newly introduced back-to-back MVDC technologies exhibit strengthened operational flexibility. We first formulate their explicit models based on real-world applications, incorporating constraints related to normal operation and power supply modes. Then, we present a day-ahead scheduling model for networked MGs equipped with these BMSs. Subsequently, we develop tractable reformulations for nonlinear constraints considered in the scheduling model, leading to a mixed-integer linear programming problem. Finally, numerical simulations on the IEEE 123-bus test system are conducted to demonstrate the effectiveness and superiority of the proposed scheduling model.