SPV grid interfaced system with reduced switch converter for power quality improvement

In this paper, a packed U-cell (PUC) based converter is connected to the solar photovoltaic (SPV) system. Here, every cell shaped in U consists two active power switches and a DC supply in between them. Whereas in one U-cell, PV array is used as dc supply and in another U-cell, a capacitor is used in between two power switches, correspondingly. Switch reduction is the prime attribution in this topology as compared to conventional multilevel topology. Here dc link voltages are determined where the value of upper half U-cell gives full range and lower half give one-third of upper portion. It decreases the complexity in the topology and also in control approach to make it a viable option. Here, switching pattern is also different from conventional multilevel converter, which is applied to the grid interfaced system. The maximum power point tracking (MPPT) is achieved using an incremental conductance method (INC), whose rate of convergence is fast. Moreover, its feasibility makes appropriate as the single stage based system, which reduces the overall cost of the system by using less number of switches to get desired levels in voltage. The decrease in multiple stage in turn, helps to improvise the overall impact of the system. Power quality analysis is carried out in order to determine the validation for an IEEE-519 standard.