New configuration of UPQC for medium-voltage application

This paper proposes a novel configuration of a unified power quality conditioner (UPQC) which can be connected to the distribution system without series injection transformers. The operation of the proposed system was analyzed through simulations with PSCAD/EMTDC and experimental works with a scaled hardware model, assuming that the UPQC is connected with the 22.9-kV distribution line. The proposed UPQC has the ultimate capability of improving power quality at the point of installation on power distribution systems. It has flexibility in expanding the operation voltage by increasing the number of H-bridge modules. Index Terms--dynamic voltage restorer (DVR), H-bridge, PSCAD/EMTDC, static synchronous series compensator (SSSC), Static var Compensator (STATCOM), unified power-flow controller (UPFC), unified power-quality conditioner (UPQC).