Operation analysis of novel UPFC based on 3-level half-bridge modules

This paper proposes a novel UPFC based on 3-level half-bridge modules, isolated through single-phase multiwinding transformers. The dynamic performance of proposed system was analyzed by simulations with EMTDC, assuming that the UPFC is connected with the 138-kV transmission line of one-machine-infinite-bus power system. The proposed system can be directly connected with the transmission line without series injection transformers. It has flexibility in expanding the operation voltage by increasing the number of 3-level half-bridge modules.