The As400 Power Control and Distribution Unit - A Modular and Flexible Unit With B2r Solar Array Regulation For High Power Leo Missions

Abstract

This paper presents the ‘High Power’ Power Control and Distribution Unit (HP-PCDU) which has been designed as modular and generic equipment in order to cope with the growing power demand of Low Earth Orbit (LEO) missions. Next to the AS400 satellite platform of Airbus Defence and Space it will be used for the MetOp-SG satellites. The HP-PCDU supports unregulated bus voltages of 50V and 100V and provides a 30V secondary regulated power bus. Solar Array Regulation with Maximum Power Point Tracking (MPPT) is performed by Buck-Boost-Regulators (B2R) operated in a cold-redundant ‘N+1’ topology. A new FDIR strategy based on discrete hardware protections and FPGA-logic for autonomous failure handling is presented. Next to an outline of other power control and distribution functions this paper also includes a summary of the novel High Rate Diagnostics Mode that allows monitoring telemetry signals with a time resolution up to 200μs.