A low cost single phase grid connected reduced switch PV inverter based on Time Frame Switching Scheme

摘要

The domain of Grid Connected Inverter (GCI) and reduced switch topology in multi-level inverter (MLI) are gaining its attention in terms of reducing cost and optimization. For such a motivation, many researchers are addressing their efforts in proposing new MLI topologies or in modifying the existing ones, aiming at improving the quality of the energy available at the inverter terminals. The proposed split capacitor based topology uses only a single dc supply to generate any required output levels. The split capacitors are considered to obtain stepped output by adopting a Time Frame based Switching Scheme (TFSS). The numbers of semiconductor switches are reduced with an improvement in the harmonic factor. The power output is then filtered using passive inductor component and then synchronized to feed the grid power system. The result of the proposed topology is verified by Matlab/Simulink simulation and hardware implementation using a dsPIC30F4011 controller. The simulation and experimental results are compared to previous studies. The proposed scheme offers an excellent performance with significant result in lowest THD obtained and also enables the inverter to operate under unhinged PV conditions comprehensively. (C) 2015 Elsevier Ltd. All rights reserved.