Abstract
This paper discusses transient stability boundaries in an ac/dc power system. The stability boundaries mean basin boundaries of stable equilibrium points (EPs), which correspond to post-fault steady states of the ac/dc system, and essentially govern its transient stability. Our previous studies numerically clarified a stability boundary in the ac/dc system based on a differential-algebraic equation (DAE) system. This paper theoretically characterizes stability boundaries based on the DAE system. The obtained characterization reveals concrete structures of the stability boundaries in solution space of the DAE system.
