Global control with application to bifurcating power systems

A multilevel nonlinear control scheme that is capable of system control over wide ranges of operating conditions is proposed. The first control level confines the system operation to some reference segments in its state space. Each reference segment is further subdivided using the bifurcation analysis for establishing the bounds of the state space of the system with different control requirements. The principles of global control lead to a hierarchical control structure which combines regional (linear or nonlinear) controllers smoothly. The scheme is illustrated for control of a power system known to have diverse dynamical behavior. The control will accomplish desired steady-state (fixed point or small oscillation) operation of the power system for a wide range of loading levels. (C) 2000 Elsevier Science B.V. All rights reserved.