POWER QUALITY IMPROVEMENT WITH UNIFIED POWER QUALITY CONDITIONER USING SRF CONTROL STRATEGY
Keywords:
UPQC, shunt filter, series filter SRF theoryAbstract
the unified power-quality conditioner (UPQC) is used to mitigate the current and voltage-related powerquality (PQ) problems simultaneously in power distribution systems. Among all of the PQ problems, voltage sag is a
crucial problem in distribution systems. Sags are mostly caused by fuse or breaker operation, motor starting, or
capacitor switching in power system. In power transmission line and distribution line voltage sag are non-repetitive,
or repeat only with few times due to reclose operation. UPQC consists of back to back connected series and shunt Active
Filters The shunt active power filter compensates the source current harmonics and also it maintains the dc link voltage
unchanged in steady state, while the series active power filter compensates the load voltage harmonics.
A MATLAB based model for the UPQC has been simulated for R-L load using synchronous reference frame based
technique