In any level of DC Voltage the variable of modulation index values are interested to analysis the quality of DC current for modulation index less than 1 low order harmonics is eliminated but low order harmonics increase when modulation index more than 1, ripple voltage nearly constant for modulation index increase and efficiency of system less than 70% for modulation index less than 1 but for modulation index more than 1 then efficiency of system more than 70% the analysis of this can be to improve and apply in the future.