Advanced Technologies on Distributed Power Supplies Applied to Space Instrumentation J. Rodrigo, J. Jimenez, M. Herranz, J.M. Castro‐Marin, L.M. Lara TECHSS (Technology for Missions Group) Instituto de Astrofísica de Andalucía (IAA), Consejo Superior de Investigaciones Científicas (CSIC)

ABSTRACT Within the framework of the (ESA) 2015‐2025 program, members of the Solar System Department and of the ‘Unidad de Desarrollo Instrumental y Tecnológico’ (UDIT) at the ´Instituto de Astrofísica de Andalucía´ (IAA‐CSIC) have acquired several responsibilities inside the international consortiums for missions in development. Some of these responsibilities are related to the development of different space power supplies for diverse instruments, each with specific requirements that make them unique. Nowadays, many different power supplies solutions are being studied, simulated, fabricated and tested in‐house in the early phases of their respective projects. A brief summary of these space power supplies is presented, as well as their technology state‐of‐the‐art, advantages and disadvantages for their future use in space.

IAA internal –> DM, EBB: BepiColombo ‐ BeLA ESA delivery –> EM, EQM, FM: Modular ´BepiColombo Laser Altimeter´ Discrete philosophy philosophy BeLA Power Converter Module (PCM) Requirements PHASE 0‐B • Fully redundant configuration • Protections: PHASE D • Soft‐Start. FPGA reset ‐ Short circuit • 50W, around 600 g PCB mass ‐ Overcurrent, under‐voltage, hiccup • Efficiency better than 75% ‐ Inrush limiter • Galvanic isolation ‐ Common & Differential mode input filtering

Initial (DM) Final (FM) Requirements Tests to compare technology performances: Requirements

cond / out cond  Secondary Voltages levels + 28 V  Output power levels + 28 V + 12 V  Inrush, efficiency + 12,6 V ±5 V cond / out  ±5,3 V ELU BACKPLANE Temperature, Housekeeping + 3,3 V  FPGA Communications + 3,4 V

cond / out cond  Electromagnetic Compatibility (EMC) Nom: 13,5 W  Thermo‐Vacuum (TV) Nom: 16,2 W Peak: 43,9 W Peak: 51,9 W LEU: Laser Electronics Unit RFM: Range Finder Module ´BepiColombo´ DPM: Digital Processing Module

Modular JUICE ‐ Development JUICE ‐ GALA Discrete philosophy ´Jovis Amorum ac Natorum Undique Scrutator´ Model (DM) ´GAnymede Laser Altimeter´ philosophy

PHASE A JANUS Power Supply Unit (PSU) PHASE A GALA Power Converter Module (PCM) Modular ‐VS‐ Discrete Requirements Pros: Cons: BepiColombo – BeLA direct heritage  Mass reduction  No heritage defined  Area and volume reduction  TRL low  Cost reduction  ITAR controlled parts  Efficiency increase  Less ´customizable´ +28V filtered

ME

28V DC-DC -12V FW Filter +12V filtered DC-DC Filter & + 12V ±12 V +/- 12V +12V Cover RFM DPM 7V? Soft-Start + 7 V Soft-Start TBD LEU -5V -5V DC-DC PE DC-DC ±5 V 28V +/- 5V 28V +/- 5V + 28 V Inhibit +5V Inhibit +5V + 3,3 V S/C S/C + 12,6 V DC-DC 3.3V 3.3V + 2,5 V DC-DC ±5,3 V General 3.3V MCU CPCU + 3.3V DC-DC /CU 2.5V + 1,5 V 2.5V Modular phil. + 3,4 V PCM Requirements MEU DC-DC 1.5V 1.5V Nom: 21,9 W PSU TBC Nom: 14,5 W Peak: 32,4 W Peak: 47,3 W CPCU: Command and Process Control Unit CU: Compression Unit FW: Filter Wheel ´JUpiter ICy moons Explorer´ LEU: Laser Electronics Unit RFM: Range Finder Module MCU: Mechanism Controller Unit ME: Main Electronics PE: Proximity Electronics DPM: Digital Processing Module MEU: Main Electronics Unit

Modular R ‐ MaRIS Marco Polo R ‐ MaNAC Modular philosophy ´Marco Polo‐R Imaging Spectrometer´ ´Marco Polo‐R Narrow Angle Camera´ philosophy

PROPOSAL MaRIS Power Supply Module (PSM) MaNAC Power Supply Unit (PSU) PROPOSAL PHASE A JANUS PSU philosophy heritage PHASE A • Cold Redundant. Power Bus ‐> Min: 26V Nom: 28V Max: 29 V • Filtering, isolation, overcurrent detection on primary side • Switch regulated DC/DC converters, high efficiency, galvanic isolated outputs Development • Soft‐start circuit (TBC) . EMI filters & snubbers at switching stage Model (DM) • Short‐circuit & over‐current protection on secondary • Analog housekeeping ‐> FPGA and LVDS communications + 25 V ±15 V + 15 V ±8,5 V + 7 V ±5 V ±5 V + 4 V + 3,3 V + 3,3 V

Nom: 19,9 W Nom: 13,5 W Peak: 23,9 W Peak: 17,5 W DPM: Digital Processing Module PEU: Proximity Electronics Unit ´Marco Polo ‐ R´ PEU: Proximity Electronics Unit FPA: Focal Plane Array MEU: Main Electronics Unit MEU: Main Electronics Unit

SUMMARY • Discrete philosophy boards has been designed, fabricated and tested to compare the performances and advantages/disadvantages of each technology philosophy • Similar General requirements for space power supplies, different specific ones (i.e. secondary voltages, power dissipated…). Discrete and modular philosophies are feasible a priori. • Modular philosophy development model boards (DM) are currently in study and test in order to raise TRL (Technology Readiness Level) up to 6 (actual = 4). Emerging technology • Technology philosophy timeline (at IAA): Phase D –> Discrete (Modular studied) Phase 0‐B –> Discrete / Modular (discrete back‐up) Future Missions –> Modular proposals