Coordinated Power Control Strategy of Modified Electrical Energy Router

Energy storage system (ESS) is generally applied in electrical energy router (EER) for flexible interfacing with renewable-energy sources. However, the complex structure and power flows of EER-ESS raise new requirement that coordinated power control is supposed to be adopted. In this paper, a modified EER (MEER) with two-level super capacitor ESS (SCESS) is proposed for energy interconnection and power buffering in medium and low voltage distribution network. The three-stage configuration and corresponding control strategies of MEER are introduced in detail. After analysis of the typical power flow situations, a coordinated power control strategy is proposed to achieve flexible power management between SCESS and renewable-energy sources under different operation conditions for the system stability. The effectiveness of the proposed coordinated power control strategy is finally verified by the simulation and experimental results.