Abstract:Power supply and distribution system is an important part of the spacecraft electrical system, which provides and distributes power energy for all the equipments in spacecraft, whose performance is directly related to the success or failure of the mission . In order to improve the reliability and intelligence of spacecraft power supply and distribution system, based on the function and composing of power supply system for spacecraft, combined with engineering experience, this paper expounds the key technique and method which make the power supply system more reliable and intellectualized, such as SSPC intelligent power distribution technology, system redundancy technology, fault isolation technology, bus-control technology, inrush current suppression technology etc . The system is validated successfully in the field experiment, and test data has been analyzed in this paper.