Design of Power Supply System of Asteroid Exploration Spacecraft

The mission targets of the Chinese asteroid exploration are an earth co-orbiting celestial body 2016HO3 and the main-belt comet in the asteroid belt. Compared with Lunar Exploration and Mars Exploration missions, asteroid exploration mission is special. The light intensity varies widely during the mission, resulting in a large change in the output power range of the solar array, which seriously affects the power system design and the load design during the mission; the spacecraft uses a high-power electric propulsion system; the power system has strict weight requirements, the existing power supply system design cannot meet the requirements. Aiming at the design constraints of the large variation of solar wing light intensity, the large difference in power requirements between the electric propulsion and the platform, and the lightweight design of the spacecraft, a dual-bus power supply system is proposed. High-voltage bus power the electric propulsion system. The solar cell array directly converges to form a high-voltage bus, which supplies power for the electric propulsion system. The low-voltage bus adopts a semi-adjustable bus, and the solar cell array adopts a circular flexible solar wing. The main detector and return cabin are equipped with lithium-ion battery pack and lithium fluorocarbon battery pack respectively. Aiming at the requirement of long-term on-orbit operation of electric propulsion system, a solar wing output power measurement system is designed. Product test results show that the power system design can meet the working requirements of electric propulsion and platform loads. The power system design can provide reference for the other deep space exploration power system.