Design of a Passive 48-Pulse AC-DC Converter for THD Stabilization at Light Load

摘要

In this paper a 48-pulse uncontrolled AC-DC converter is proposed to mitigate AC line current harmonics of the input side. The proposed rectifier uses conventional 24-pulse parallelly connected rectifier with addition of a passive current injection circuit named as special interphase reactor. The interphase reactor consists of two additional lower rated power diodes. The value of the found THD is 3.55% which satisfies the IEEE 519-1992 standard. Proposed converter also shows lower fluctuation of harmonics valued 1.40% with respect to full load ensuring stable operation at light load. Designed multipulse converter scheme is also simple in construction and requires less number of electronic devices compared to conventional 48-pulse AC-DC converter. This article also explains the simulation and THD performance of the proposed AC-DC converter with proper figures.