Design and implementation of shunt active power filter for harmonic reduction in grid connected solar photovoltaic system

Abstract

Nowadays, the renewable based power generating system struggles with power quality issues due to the illustration of voltage and current harmonic distortions owing to power electronic devices. The long-term voltage sag, swell and current harmonics are reported as major power quality issues, which frequently occurred in both single phase as well as three-phase power distribution network. The wide use of non-linear loads such as variable speed drives, diodes and Thyristor Controlled Rectifiers (TCR), Uninterruptible Power Supplies (UPS), and other house hold electronic components directly inject harmonics into the power system with their non-linear switching characteristics. The presence of harmonics in the power distribution systems reduces the life time and also makes malfunctioning of the apparatus which are all connected to the power system network. Hence, harmonic mitigation and reactive power compensation techniques is compulsory required nowadays and it excite more researchers to concentrate on this power quality enhancement. Conventionally, passive filters are used to mitigate the harmonics, but it has certain limitations such as resonance problems, large size and fixed filtering characteristics. The shunt APFs are employed to diminishes the current harmonics and series APFs are utilized to mitigate the voltage harmonics, voltage sag and swell. For power quality improvement there are various linear and non-linear control schemes based on APFs have been implemented by many researchers. A forceful control approach is designed based on the computational technique and automatic revision of the controller. The controller performance can be modified by remodeling the system variables. Artificial intelligence has been employed to design a suitable controller for tracking an appropriate reference signal. An adaptive technique has some potential features such as self-learning and selforganizing. The instantaneous real and reactive power theory and Unit Vector Template (UVT) control scheme is chosen for extracting fu