Distributed power supply for payloads aboard space vehicles

An optimized solution for the problem of power distribution aboard space vehicles is proposed. It is based upon a DC to DC phase-shifted, high frequency switching converter: the “switch in line converter” (SILC), characterized by disposition in line of the MOSFETs and good soft switching performances. The operating principles of the SILC are described making reference to steady state waveforms. The converter acts as a controlled current generator and its small signal linear model has a first order dynamics. It is well suited for supplying constant power loads. An example of multioutput, 100W converter is considered and the experimental results obtained by a prototype are compared with the dynamic forecasts from the linear model. Without taking into account the losses of a terminal point-of-load low output voltage converter and the losses of possible current limiters and low drop regulators for the analog circuits, the efficiency is above 85% at full load and it keeps high down to less than half load.