Performance evaluation of interphase transformers based on a new 48-pulse AC–DC converter for industrial applications

Abstract

This paper evaluates the performance of two arrangements of interphase transformers using a new AC–DC 48-pulse converter (SC-48P) for industrial applications with high currents in the order of hundreds of kiloamperes, so that consumers and other loads connected to the SC-48P electrical grid are not affected by the harmful effects caused by harmonic currents injected into the grid by converters. The prototype uses a 7.5∘ and 4 kVA-220/220 V three-phase phase-shifting autotransformer and two groups of 24-pulse converters, each containing two 2 kVA-220/180/180 V identical three-phase three-winding non-conventional transformers with four 6-pulse converter bridges connected in parallel. The methodology for calculating the inductance for each IPT is given using the mathematical formulation of AC currents established and processed using the MathCad software. Computational simulations in normal and degraded modes were conducted in MATLAB/Simulink to prove the prototype’s performance in terms of harmonic distortion and reliability, considering only three operational scenarios. The SC-48P was experimentally tested using available laboratory resources to validate the research. The obtained results meet IEEE-519 requirements and confirm the viability and applicability of the proposed converter in industrial rectification systems in terms of power quality improvements.