Interleaved Luo converter for the residential PV grid connected systems

The new research trend in the residential solar generation systems, is to employ the parallel connected PV configuration rather than the series-connected configuration to satisfy the safety requirements and to make full use of the PV generated power. A novel interleaved Luo converter is proposed for the high voltage gain DC-DC conversion which integrates the merits of interleaved topologies and switched capacitor based topologies. The Super Lift (SL) Luo converter is becoming very popular in the DC-DC conversion processes due to high voltage gain, and simple circuitry. By using the interleaving technique, the input current ripple and output voltage ripple of the elementary SL Luo converter is reduced. Hence the proposed topology is suitable for the DC-DC conversion at the output of parallel/seriesparallel connected PV modules, since the low ripple current at the output of PV module will improve the life span of the same. Incremental conductance based MPPT control algorithm, along with a PI controller is implemented in this paper. The disadvantage of the interleaved topology is the large component count. However, component ratings of the Interleaved SL Luo converter are reduced to half of that of a SL Luo converter. Hence the cost of the interleaved circuit can be justified.