Modeling and analysis of multiconverter unified power quality conditioner

The increasing use of sensitive loads make it necessary to solve power quality problems and to use custom power devices. Active filtering, load balancing, power factor correction and voltage regulation in distribution systems are possible with the use of voltage source converters (VSC) based custom power devices.In this thesis, one of the known interline custom power devices named Multiconverter Unified Power Quality Conditioner (MC-UPQC) is modeled in PSCAD/EMTDC. The developed topology can be used for simultaneous compensation of voltage and current imperfections in multibus/multifeeder systems. The proposed MC-UPQC is designed for medium voltage level (11 kV) and effective EPLL based control technique is used to detect and extract the PQ disturbances. The performance of Series Compensators of MC-UPQC is evaluated through extensive simulations for mitigating balanced and unbalanced voltage sags with phase jumps, swells and interruptions. The performance of Shunt Compensator of MC-UPQC is also tested for harmonic compensation, reactive power compensation, and DC link voltage regulation.It is observed that MC-UPQC which is connected to two feeders, can compensate current and voltage distortions succesfully in these feeders according to the results obtained using PSCAD/EMTDC.