This paper presents the performance of custom power devices in a Custom Power Park (CPP) by series and shunt compensation in a distribution supply system. A static transfer switch (STS) provides alternate feeder supply to park loads where shunt active power filter (SAPF), and a dynamic voltage restorer (DVR) are employed to compensate current harmonics, voltage sag, and voltage interruptions. A novel voltage detection controller based on single-phase synchronous d-q reference frame is developed which can detect single or three-phase balanced/unbalanced voltage imperfections. Extensive simulation studies are carried out by using PSCAD/EMTDC software and the ability of CPP to provide a group of customers with premium quality of power is analyzed. © 2012 IEEE.