Certain investigations on control strategies for UPQC to mitigate power quality issues

Abstract

In recent years a custom power device plays an indispensible role in electric distribution network due to the effects of poor power quality As a result of the standards implemented by IEC IEEE and many other committees it has become mandatory to abide the rules to reduce the penalty being levied on the industries Not only as an industry oriented view the power quality issues may also lead to loss damage or degradation of the equipments which creates alarm to maintain standards even in the residential facility It is evident from the research that the usage of non-linear loads or the loads which consume more reactive power like Variable Speed Drives VSD frequency changers etc may cause power quality problems These power quality problems may affect other loads connected to the same grid The most common trivial power quality issues are voltage sag voltage swell interruption harmonics and flicker In view of this Dynamic Voltage Restorer DVR Dynamic Static Compensator DSTATCOM and Unified Power Quality Conditioner UPQC are the premier devices to address the aforementioned issues The DVR considered to be an effective tool for voltage sag mitigation works by injecting voltage of required magnitude and frequency is in series with an injection transformer whereas DSTATCOM can provide load compensation by injecting current with an Voltage Source Converter VSC On the other hand, the universal active filter named Unified Power Quality Conditioner UPQC is capable of addressing all the power quality issues cited above UPQC is well known to deal with the issues that affect the performance of the sensitive loads The main focus of research is to investigate the behavior of UPQC with conventional and AI based controllers for different power quality issues and to ensure proper working of the system under non-linear load conditions newline