Comparative analysis of single-phase to three-phase converters for rural electrification

This work presents a comparative analysis of single-phase to three-phase converter's. The purpose is to develop electronic converters suitable to supply consumers in rural or remote areas. The implementation of electrical utility services in these areas has been challenging due to high costs and to the increasing demands for better quality services. Single-phase feeders have been considered a less costly alternative as far as installation and maintenance is concerned. In this case, the converter output must operate as a four-wire three-phase system, in order to supply single and three-phase loads. Some assessment studies have outlined performance requisites for achieving better power quality, such as: ride-through capability during voltage sags, input current wave-shaping with power factor close to unity, and regulated three-phase voltages with unbalanced loads. In this work several single-phase to three-phase topologies were depicted from the literature and analyzed with power ratings at 15 kVA. It was verified that none of them could satisfactorily attend those quality requisites for acceptable operation, design requirements and costs. New topology configurations are proposed with improved performance characteristics, along with their specification guidelines and design considerations. The analysis is carried out through simulation results obtained from an electromagnetic transient simulation package (PSCAD/EMTDC/sup /spl trade//).