Power quality of renewable isolated power systems — A case study

Isolated power systems, which generate power at site, are considered as a viable option for the electrification of rural villages which are far away from the utility grid. In India, there are many such villages which have been electrified through renewable isolated power plants like biomass gasifier and solar photovoltaic (PV) systems. Case studies have been conducted for such a biomass gasifier based isolated power plant in the state of Maharashtra, India. This paper discusses the various power quality measurements taken at site during its operating hours. It has been observed that the large unbalance and high THD (Total harmonic Distortion) in voltage and current leads to excess heating of motor loads and over head line conductors in the network. The measured data shows that some improvements in the power quality of isolated power systems are required to bring it on par with grid power supply.