A sensorless control technique for low cost AC/DC converters

Abstract

This paper proposes a sensorless technique capable to reconstruct the input currents of a three-phase active rectifier using only a DC-link voltage sensor and a PLL circuit in the line side. It has been developed in order to design a low cost three-phase active rectifier and it is based on the novel PMM (power matching modulation) technique and on the control of the capacitor energy. The proposed system guarantees close-to-unity power factor, excellent output voltage regulation, limited current harmonic content, high efficiency and low cost.