Power Quality Improvement and PV Power Injection by DSTATCOM with Variable DC Link Voltage Control from RSC-MLC

The study proposes a method to optimize dc-link voltage of distribution static compensator based on load compensation requirement using reduced switch count multilevel converter (RSC-MLC) integrated with photovoltaic (PV) system. The proposed method is capable of compensating reactive power, unbalance, and harmonics demanded by three-phase unbalanced and nonlinear loads connected to the distribution side, leading to improvement of power quality. It is also capable of providing real power support to the load and thus prevents source from getting over loaded whenever required. During off-peak loads, the dc-link voltage can be brought down to a lower value, which will reduce the voltage-stress across switches of inverter and minimizes the switching losses. The variation of dc-link voltage is provided using RSC-MLC, which requires dc voltage supply. This method utilizes renewable resources of energy such as solar cells as the dc voltage source. The output voltage of PV panel is boosted to a higher value using high gain boost converter and given to RSC-MLC. The maximum power point tracking of PV panels is achieved by using Perturb and Observe algorithm. The results have been verified through simulation and experimental studies.