A comparative study of FPGA based cycloinverter with two modulation techniques

A cycloinverter has been analyzed using two modulation techniques namely delta modulation (DM) and trapezoidal modulation (TM). Field Programmable Gate Array based digital controller has been developed to generate the trigger pulses for cycloinverter using Hardware Description Language. Lowest THD has been found to 2.5% for DM and 5% for TM when modulation index m = 1. There is no specific pattern for the value of THD for different value of frequencies but still DM is better as compared to TM. The circuit has been tested qualitatively by observing various waveforms on DSO. Tests have been carried out to show the effectiveness and flexibility of the proposed method.