Design and Development of Multiple Output, Low Noise Space Qualified DC-DC Converter with Emphasis on Miniaturization and Performance Optimization

Abstract

Power supply is the most crucial and essential subsystem in any satellite. Sun is the only source of power in space and from that, dc voltage of 28 V to 42 V is derived. It is required to have an isolated and regulated power supply that can be given to a payload of any satellite. The most convenient converter for space application is flyback converter with multiple outputs because of its compactness and single switch control that reduces overall size of the power supply, which is the key point in space application. The developed power supply design for space application is flyback converter having 6 output voltages for electro optical payload of a remote sensing satellite, from which first 3 outputs are obtained from multiple output flyback converter-A (in total 12.86 W) and the other 3 from flyback converter- B (in total 30.1 W). In total 16 cards of converter A and B are to be implemented for the payload as per existing design. As a result, total 32 cards are required for power supply, so it gets bulkier and spacious for any satellite’s payload. Now, to develop a more compact and miniaturized design an attempt is made by changing transformer size and reducing footprint of various inductors, LDOs and linear regulators. Two multi-output flyback converters A and B are to be implemented into the same PCB layout dimension (160 mm x 115 mm) that has been implemented for a single card in the existing design so as to reduce the size by 50%. The proposed flyback converter PCB layout also consists of output under voltage protection that also incorporates output short circuit protection, input under voltage protection, input over-current protection and PPS on-off as well as select-deselect circuits.