Distributed Power Control for Transient Stability of Multimachine Power Systems

Transient stability is a key problem in power systems. Conventional methods enhancing the transient stability are always based on local information with a prior knowledge of an equilibrium point that may not be available for large disturbances. This paper puts forward a distributed power controller for improving transient stability of multimachine power systems. The distributed controller depends on the relative angular speed of each generator with respect to its neighboring generators, rather than on state errors from an equilibrium point, so that the requirement of knowledge of equilibrium point is relaxed. By making use of the Popov criterion, it is shown that the closed-loop system is asymptotically stable. Improvement of transient stability is then discussed. Simulation results compare the decentralized and distributed control for achieving frequency synchronization.