Stability Analysis for a Large-scale Space Power Network, International Space Station and Japanese Experiment Module

Abstract

The International Space Station (ISS), which is scheduled to start the operation fully in early 2000’s, is being developed and assembled on orbit since 1998 with international cooperation of the USA, Russia, Europe, Canada, and Japan. Japan participates in this ISS program and will provide the Japanese Experiment Module (JEM, named “Kibo") which will be attached to the ISS core. Japan Aerospace Exploration Agency (JAXA), which is responsible for the JEM system development and integration, has been developed JEM Electric Power System (JEM EPS) as part of the Space Station Electric Power System (EPS). The International Space Station Electric Power System is the world’s largest orbiting direct-current (DC) power system. The ISS electric power is generated by solar arrays, and distributed to the each module in 120 Vdc bus voltage rating. When designing a large-scale Space Power System using direct current (DC), special attention must be placed on the electrical stability and control of the system and individual load on the system. For a large-scale Space Power System, it is not feasible to design the entire system as a whole. Instead, the system can be defined in term of numerous small blocks, and each block then designed individually. The individual blocks are then integrated to form a complete system. The International Space Station (ISS) is one of good example for these issue and concerns as a large-scale Space Power System. This paper describes the approach of the stability analysis for a large-scale space power network.