In this paper steady-state stability analysis algorithms, based on operations with systems of equations of subsystems on lower level and coordinating operations on upper level of control system. This approach to steady-state stability analysis makes solution of these problems in large power systems much easier compared with solution of, based on analysis of matrix of system of equations for power system as a whole. Most efficient realization of these algorithms can be achieved on distributed control system, which includes computers of lower layer, installed in control centers of subsystems and computer of upper layer – server.