Interline hybrid unified power quality conditioner

This paper proposes a new interline hybrid unified power quality conditioner (IHUPQC) structure to improve the power quality of distribution feeders and to decrease the power ratings/voltages and switching losses of voltage source converters (VSCs). The IHUPQC consists of dynamic voltage restorer (DVR), an isolated dc-dc converter and a shunt hybrid active power filter (SHAPF) with a common dc bus. The inverse park phase locked loop (IP-PLL) technique is used to detect the distortions of signals in both feeders. Sinusoidal pulse width modulation (SPWM) based voltage control and current control are used for DVR and SHAPF respectively. The isolated dc-dc converter has PI controller based simple phase shift (SPS) technique. The proposed structure is designed for 34.5 kV voltage level and simulated by using PSCAD/EMTDC to verify system.