Research on droop control strategy for interconnection ports of two-level energy routers

In the context of the “dual carbon” goal, energy routers are increasingly widely used. To address the challenge of controlling multi-level energy routers across various operating states, this paper proposes a bidirectional droop control strategy for their interconnection ports. The control system uses the DC bus voltages on both sides of the interconnection port to assess the electricity demand of the upper and lower-level energy routers. It then derives the required magnitude and direction for both the transmission power and the loss power. The control architecture includes two droop links: the upper level DC voltage active power and the lower level DC voltage active power, and the difference between their outputs is used as the power reference value for the interconnection port. This dual variable droop control can more accurately coordinate the energy transfer between upper and lower level energy routers, achieving full utilization of electrical energy. A simulation model was built using Matlab/Simulink and compared with the power transmission of a two-stage energy router without interconnection ports to verify the correctness and rationality of the control method.