PV Fed Cascaded Modified T Source Converter for DC Support to Grid Coupled Inverters

Photovoltaic panels under partial shading conditions influence heavily on output voltage. With higher penetration of renewable energy sources and imposition of stringent grid codes; it is mandatory for the inverters to remain connected for grid support despite of voltage variations on DC bus. This paper, proposes a cascaded connection of modified T-type converter on DC bus with each converter having separate PV source to support the grid even under partial shading. The converter is shown capable of boosting in normal mode and providing auxiliary boost in shoot through mode, providing efficient and wide operating band. The simple modular architecture of the converter with simple control allows plug and play operation, suitable for microgrid. The performance of the proposed converter system interfaced with the grid is simulated for input voltage variations to affirm the efficient and wide band operation to feed power to the grid.