Sinewave error modulation control for harmonics reduced bridge rectification

A control technique is proposed for bridge rectification improvement in order to diminish the unwanted harmonic contents, and to regulate the output voltage in case load variation is sufficient. The technique is based on sinewave error modulation (SEM) that applies output voltage regulating loop to provide a dynamic sinewave error reference template for the process of pulse width modulation. The primary loop is therefore designed to stabilize DC side output voltage, and in the same time the sinewave error modulation is intended to get rid of the unwanted harmonics. Also, to point out that low cost improvement is possible, the prototype was then implemented using peripheral interface controller IC (PIC). By comparing results of the improved rectification with those of the traditional rectifier, both from simulation and experiment, the SEM is seen to be one of the effective techniques. It covers both drawbacks; output voltage was regulated even if sufficient load variation was imposed on, and the unwanted harmonics appear on the distorted input current was diminished satisfactorily.