Harmonics assessment of domestic and commercial loads and evaluation of control techniques for shunt active power filter

Attention towards power quality has increased because of massive utilization of power electronic based equipment and other nonlinear appliances. Harmonic distortions are regarded as one of the most remarkable causes for power quality issues. Sources and effects of harmonics have been presented for the purpose of strict implementation of power quality (PQ) standards such as IEEE 519 and to impose penalties for violating PQ standards. In this thesis, the harmonics drawn by the different commonly used domestic and commercial loads has studied through an experimental survey. The experimental results reveal the importance of harmonics related appropriate regulation and policy to be recommended by the concern power authority to maintain harmonics within the permissible limit. Also, this study implies the importance of active filters which can effectively suppress the harmonics to maintain harmonics within the acceptable limits. The shunt active power filter (SAPF) be the part of widely used active filters to suppress the harmonics produced by the nonlinear equipment. The core part of the SAPF is control techniques utilized for reference current generation. This thesis presents a comprehensive study of three control techniques namely instantaneous reactive power (p– q) theory, synchronous reference frame (SRF) theory and modified synchronous reference frame (SRF) theory for SAPF in a three phase three wire secondary distribution system. These three control methods aims to compensate harmonics, load unbalance and reactive power under sinusoidal balanced supply voltage conditions. Simulation results present a relative investigation of three control techniques based on current THD and load unbalance