Harmonics reduction of three-phase boost rectifier by modulating duty ratio

Line currents of three-phase diode bridge rectifier suffer from high THD. This THD is higher than IEEE standards. Injection of six harmonic components from the DC bus back to the duty ratio of the boost converter connected to the three-phase diode bridge rectifier reduces the THD of the utility line current. In this study a sine wave and a triangle wave with six times the fundamental frequency is presented. The analysis has been carried out to reduce THD of the utility line current of three-phase boost rectifier. The THD of the utility line currents depends on the amplitude and phase-shift of the six-order component injected to the duty ratio of the boost converter. A complete mathematical and simulation analysis of the injection technique has been carried out. The mathematical analysis and simulation results of 6 kW prototype system show the superiority of the proposed injection technique.