Harmonic compensation as ancillary service in PV inverter based residential distribution system

Abstract

The reliability and cost of any electrical system depends greatly on the quality of the power supplied to and consumed by the system. The electrical utilities are very much concerned about the power quality due to the presence of nonlinear loads in their power distribution systems. The Non linear residential loads cause harmonics in the residential distribution systems. To mitigate the harmonics, active or passive filters are normally used. In the recent years there is an increase in the installation of the Distributed Generation (DG) systems in the residential areas. Especially renewable energy based DG's such as Photovoltaic (PV), Wind, Biomass etc. are getting considerable interest and are installed in residential areas. These DG systems have DG-Grid interfacing converters and with the increased implementation of DG systems the use of interfacing converters to reduce the harmonics was proposed. In this paper, the use of PV interfacing inverters was considered. The concept of virtual harmonic damping impedance for the control of PV interfacing inverters was proposed for improving the power quality of the residential distribution system. The residential load and DG systems were modeled and compensation of the current harmonics in the system by using the virtual harmonic damping impedance concept was carried out. These were analyzed and verified using simulations.