Cascaded H-bridge multilevel converter for grid connection of photovoltaic system

This paper describes the characteristics of cascaded converter and details the work of cascaded H-bridge multilevel converter which use phase shifted carriers pulse width modulation. Use cascaded H-bridge multilevel converter instead of ordinary inverter, we can get a photovoltaic power generation system which has a multilevel output voltage. The PV system can be high-voltage grid, thus eliminating a lot of step-up device. It has higher safety and the risk of the short circuit of the direct-current is greatly reduced. So it has been widely used in medium and high power applications. At last, a simulation is performed to test the model, and the conclusion shows its correctness and validity.