Implementation of Grid-connected Single-phase Inverter Based on FPGA

Exploiting the capability of an FPGA, a digital current controller of a single-phase inverter for grid interface is designed and implemented. A proportional and resonant (PR) controller realized in a parallel structure in the FPGA is used to reduce the harmonic current to AC grid. The harmonic compensators based on the PR controller are implemented up to the 19^th order. The size of the LCL filter has been extremely reduced because the switching frequency is increased to 100 kHz. The validity of the FPGA based grid-connected single-phase inverter has been evaluated by experimental results.