High-density bidirectional rectifier for next generation 380-V DC distribution system

A high-density bidirectional rectifier was developed not only for telecom and data center applications but also for next generation 380-V DC distribution systems. A conventional rectifier consists of an AC 200-V/DC 380-V power factor correction (PFC) converter and an isolated DC 380-V/DC 380-V converter, and the power flow is unidirectional. Two approaches are proposed for creating a high-density bidirectional rectifier for future applications. One uses Silicon Carbide (SiC) JFETs and SBDs for the bidirectional three-phase PWM conversion on behalf of the conventional unidirectional PFC converter. The other uses a series-parallel combination methodology of highly integrated low-voltage and low-power dc-dc converters to create an isolated dc-dc converter to create a higher density. A prototype of a rectifier with 5-kW of output power was developed and experimentally verified. A volume reduction of 30% is expected. The details and the methodology for creating this higher density bidirectional rectifier are described in this paper.