Next-Generation DC Power Flow Controller Toward Future DC Grids: A Disruptive Module-Based Design

DC power flow controllers (DCPFCs) could effectively enhance the controllability of power flows in meshed DC grids. Evolved from traditional DCPFCs, modular DCPFCs (MDCPFC) offer a module-based architecture, which has the potential to disrupt the conventional application-oriented topology design method. Concentrated on this emerging technology, this paper first demonstrates the implementation principles of MDCPFCs via analyses of a capacitor-based MDCPFC. Thereafter, key technical challenges and future development trends are discussed from three layers, i.e., the topology layer, the control layer, and the system-level operation layer. Although still at its early stage of development, MDCPFCs possess wide application potential and is an important direction for the development of next-generation DCPFCs.