Analysis and design of a three-phase offline DC-DC converter with high frequency isolation

Single-phase offline switch-mode rectifiers (or, offline DC-DC converters) face severe component stresses in applications above 10 kW. This study shows that in three-phase switch-mode rectifier (SMR) topologies, component stresses are reduced and performances improved substantially. These improvements include faster response times, reduced switching stresses of the power semiconductor devices, and reduced size and rating of associated reactive components. The authors also present an analysis and design approach for three-phase SMR converters under large input-voltage and load variations. Output voltage control is achieved by varying the duty cycle of the inverter power semiconductor switches. The theoretical results are verified experimentally.<>