Hierarchical Distributed Control of Modular Spacecraft Electrical Power System

The paper deals with the problem of low-quality voltage characterizing the common bus of a spacecraft (SC) power-supply system (PSS) with distributed three-level hierarchical control. The hierarchical control consists in the droop control of power modules connected in parallel forming a common bus for to provide uniform current distribution, which provides an increase in the impedance of this bus to such a value that is incompatible with the requirements for the voltage quality of SC onboard equipment. To solve the problem, it is proposed to apply control with three degrees of freedom (3-DOF) to divide the processes of controlling local voltages of power modules and droop control into different speeds, neutralizing the effect of the droop control of modules exerted on the impedance of the SC PSS common bus and, as a consequence, on voltage quality. The operability of the proposed solution has been verified by a series of experiments with the use of a laboratory test bench.