Abstract：Aiming at the problem of DC power flow control technology in the multi-terminal DC transmission system, a modular multi-port DC power flow controller (MM-DPFC) is proposed in this paper. Compared with the existing DPFC, it retains the advantages of no need of external power supply, bidirectional power control of the transmission line and multi-port output. Besides, it ensures the output voltage of each port of DPFC can be independently controlled based on the local and avoids the dependence on the voltage regulation at the DC outside of the main converter station in the transmission system, which enhances the flexibility and reliability of the system. At the same time,it usesthe standard modular design, which easy to achieve the port expansion and system redundancy.Firstly, the topology and working principles of the controller are analyzed in detail. Then, the corresponding control strategy is designed to ensure the effective operation of the controller. Finally, the simulation and experiment are carried out under various conditions to verify it.
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2019, Vol. 34 
