Distribution System Harmonic Mitigation using a PV System with Hybrid Active Filter Features

This paper describes the design of a photovoltaic converter with integrated hybrid active power filter (HAPF) functionality to improve power quality on three phase distribution networks. The HAPF control consists of a hysteresis band controller based on instantaneous reactive power theory to control the switching of a voltage source converter (VSC). A dc-dc boost converter interfaces a photovoltaic (PV) array to the dc link of the VSC to meet the system requirements and to inject the active power produced by photovoltaic generator to the grid. The HAPF control eliminates harmonics produced by nonlinear loads and small inverters on the distribution system. In the daytime during peak sunlight hours, the PV supplied HAPF system is in full-functioning operation mode. During the periods when there is less sunlight, the loads are supported by the main distribution system while the inverter system only provides reactive power compensation and filters harmonic currents. The simulation results show the effectiveness of the combined photovoltaic, harmonic compensation and dynamic reactive power compensation system. Moreover, the low THD (Total Harmonic Distortion) on the distribution system as a result of the designed system meets the requirements of IEEE-519.