Novel control strategy of three phase grid tied inverters for power quality improvement

Renewable energy sources (RES) are being increasingly connected in distribution systems utilizing power electronic converters. This paper presents an advanced control strategy for achieving maximum power quality benefits from the grid interfacing inverters when installed in 3-phase distribution systems. The grid tie inverter can be utilized as i) Power converter to inject power generated from RES to the grid and ii) shunt active power filters to compensate current imbalance, load current harmonics, reactive power demand and load neutral current. All of these functions may be accomplished either individually or simultaneously. This control concept is clearly explained with MATLAB/SIMULINK simulation results and THD is less than 5%.