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Unbundled power quality service is paid much attention under the circumstances of deregulation and diversification of needs of customers for quality and price of electric power. Moreover, distributed generators will be introduced to distribution system more and more, and reverse flow of active power has possibility to cause new problems in the distribution system. FRIENDS (flexible, reliable and intelligent electrical energy delivery system) is proposed as one of promising distribution system for such requirements. One of the most important characteristics of FRIENDS is that the QCC (quality control center) is installed very closely to customers in order to supply unbundled power quality service. In this paper, DC loop type QCC is proposed as one of the configurations of QCCs. Moreover the circuit configurations, the control schemes, and the simulation results of two types of PFCs (power factor correctors) which are used in this system are presented.