Grid Integration of Single Stage SPV System Using Three-Level Flying Capacitor VSC

A single stage solar photovoltaic (SPV) grid integrated power gene rating system is presented using a three level flying capacitor (TLFC) voltage source converter (VSC) operating at low switching frequency with decoupled current controller based control algorithm along with feed forward term to enhance the system performance under dynamic conditions. An incremental conductance based maximum power point tracking (MPPT) technique is used to track maximum power from SPV array, and the tracked maximum power is fed to the three phase AC grid via a TLFC-VSC at unity power factor. The use of TLFC-VSC offers the advantages of low switching losses and the operation at high voltages and high power which results in improvement of power quality with low harmonics in line currents. Simulated results validate the design and control algorithm under varying solar insolation levels at different switching frequencies.