28V bus solar array regulator based on converters with transformer and self-driven Synchronous Rectification

Abstract

Satellite power systems are generally based on non isolated topologies. Simplicity, robustness and high efficiency are the key parameters and hence, these topologies are the leaders. However, extra switches are needed for protection; the design of the MOSFET drivers is not so simple if a full excursion from 0% to 100% is needed; the design has to be changed accordingly with the design of the solar array. An alternative concept is proposed in this paper and is based on topologies with transformer. Less switches are needed for protection and just by changing the transformer turns ratio, the converter can accommodate different designs of solar arrays. The main drawback is the efficiency, which is a key player in the space power systems. To overcome this, a Synchronous Rectification system is proposed in order to boost the efficiency with respect to the diode version counterpart. A new system based on the output inductor waveforms is also proposed in this paper.