As a means to solve the problems of low reliability and high maintenance cost of flexible AC transmission system (FACTS) devices, distributed flexible AC transmission system(D-FACTS) has become a research hotspot in FACTS area with its flexible and rapid features. Based on the structures and principles of distributed series reactor (DSR) and distributed static series compensator (DSSC), a distributed power flow controller(DPFC) scheme is proposed in this paper. The DPFC sub-control unit makes the impedance adjustment of transmission lines both continuous and hierarchical. At the system level, the overall switching and continuous control of the sub-units are carried out by centralized control. Based on the scheme, the structure of a "DSSC+" type DPFC system is proposed, which has the feature of centralized control and distributed installation. The system control strategy based on online negative feedback is studied in detail. The simulation results verify the effectiveness of the strategy which can provide theoretical support for engineering applications.