(1. School of Electrical Engineering, Southeast University, Nanjing 210096, China; 2. Jiangsu Provincial Key Laboratory of Smart Grid Technology & Equipment, Southeast University, Nanjing 210096, China; 3. China Electric Power Research Institute, Beijing 100085, China)

This paper focuses on the technology of direct current (DC) power flow control suitable for voltage source converter based multi-terminal high voltage DC (VSC-MTDC) systems. Based on an analysis of existing DC power flow controllers, a novel interline DC power flow controller (IDCPFC) is proposed for VSC-MTDC systems, which has the benefit of simpler circuit topology, fewer components and no external power supply needed. A three-terminal high voltage DC system including the IDCPFC is studied and its operation principle and characteristics are analyzed. Finally, steady state, dynamic state and fault condition simulations are performed with PSCAD/EMTDC to validate the feasibility of the proposed IDCPFC. The results show that the proposed IDCPFC can effectively realize DC power flow control. This work is supported by National Natural Science Foundation of China (No. 51307024), Ph.D. Programs Foundation of Ministry of Education of China (No. 20120092120053), Fundamental Research Funds for the Central Universities (No. 2242014R30018), Scientific Research Foundation for Returned Overseas Chinese Scholars, Ministry of Education of China, Jiangsu Province “Six Talent Peaks” Project (No. JNHB-015), and State Grid Corporation of China.