Solid-State Power Substations for Future Power Grids

Abstract

The increasing penetration of renewable energy sources (RES) along with the integration of emerging energy entities is consistently reshaping the structure of the power grid. The power substations which serve as pivotal nodes in the power grid to process the electrical demands of the end-users, might be significantly impacted by future power grids featuring both AC and DC energy entities. This paper proposes a solid-state power substation (SSPS) as an alternative to the conventional substation (CS) in future power grids supporting grid modernization and unleashing the optimum benefits from the power grid. The inclusion of the DC bus within the SSPS can allow direct connection of DC sources and load, thereby supporting the integration of RESs with DC outputs and enabling the centralized monitoring and control of the energy entities. This paper presents the layout of the proposed SSPS providing a concise overview of its structure, a detailed overview of its functional working principle, and the potential benefits that can be obtained from them when compared to the conventional substation. In addition, the paper presents the hierarchical control structure of SSPS for different system-level support services. The improvement of voltage profile, reactive power support capabilities, reduction of system losses, power quality enhancement, renewable energy integration, and rapid response of protection system of proposed SSPS are validated at the system level utilizing the modified IEEE 13-node test feeder.