Stability of large DC power systems using switching converters, with application to the International Space Station

A stability approach has been developed for the International Space Station PV power system, which is applicable to any large DC power system. It is based on establishing a set of phase and gain requirements at key subsystem interface points throughout the power system, which provide good confidence that the system will be stable under small signal conditions, with reasonable performance margin. To address transient behavior and interactions between loads, two additional stages are key in providing a stable system in flight: computer modeling; and hardware verification testing. This three-pronged approach will catch any problems as early as possible and provide a practical and viable technique to ensure a robust and stable space power system.