Abstract:In view of the redundancy management and fault tolerance enhancement requirements of the SpaceVPX specification, a dual-redundant and high-reliability secondary power supply system design has been carried out. The secondary power supply module completes the conversion from primary bus to secondary power, and the SpaceUM module completes the two-level selection of secondary power group input, channel control output, and output channel switch control, achieving cross redundant fault tolerance in secondary power supply. The power management chip of the SpaceUM module realizes the secondary power input voltage, current monitoring and first-stage selection, and the output channel after the secondary power shunt is independently switched and controlled by the relay group. The power management chip simultaneously monitors the voltage and current status of each independently powered output channel, serving as the basis for relay group switch control. This enables autonomous fault diagnosis and reconstruction of the secondary power in the chassis. According to the system reliability probability analysis, the SpaceUM module can improve the reliability of the secondary power supply system compared with the whole standalone dual-redundant power supply topology. Taking the 12V/8A power supply output of a single module as an example, the standard 6U size SpaceUM module has been developed, which can meet the high reliability requirements of secondary power state detection, selection control and fault tolerance after testing and verification.