Comparison of three 3-phase converter topologies for ups applications

This work presents a comparison of power losses of three 3-phase converter topologies commonly used in UPS (Uninterruptible Power Supply) applications at rectifier and inverter operation, within a range of switching frequencies, for loads with various power factors. This study also encompasses the losses evaluation in passive elements and cooling requirements for each topology, usually neglected in previous works. The competitiveness of silicon carbide (SiC) commercial modules in 3-phase online UPSs is also addressed. A simulation model to estimate the semiconductor losses and junction temperatures is explained. Preliminary experimental results prove the effectiveness of the proposed methodology for converter losses estimation.