Design and implementation of a hybrid unified power quality conditioner with an isolated bidirectional DC-DC converter at DC link

In this thesis, a novel hybrid unified power quality conditioner (HUPQC) is proposed as an alternative solution to electrical power quality problems in distribution systems. The HUPQC is a versatile custom power device which consists of the shunt hybrid active power filter (SHAPF), the dynamic voltage restorer (DVR) and the isolated bidirectional DC-DC converter (BiDC) located at the common DC link. The power circuit design and the controller development for the HUPQC that are carried out with simulation and experimental studies are presented in detail. Proposed HUPQC provides many operational benefits such that the series voltage source inverter (VSI) has the ability to handle both balanced and unbalanced voltage sags/swells; as the shunt VSI can compensate current harmonics. Additionally, dynamic reactive power compensation capability of the shunt VSI is realized for the first time in literature within HUPQC concept by achieving adaptive DC link voltage controller. In order to verify the effectiveness of the proposed HUPQC topology and its controller, experimental studies are carried out on three phase HUPQC prototype.