Controlling bifurcation in power system based on LaSalle invariant principle

Recent investigations have shown that with systemic parameters falling into a certain area a power system undergoes subcritical and supercritical Hopf, saddle-node, and period-doubling bifurcations which severely threaten the secure and stable operation of power system, even to the point of inducing voltage collapse. To control these undesirable bifurcations, an adaptive control law is presented based on the LaSalle invariance principle, which can asymptotically stabilize an unstable power system to equilibrium points. The control technique does not require analytical knowledge of the system dynamics and operates without explicit knowledge of the desired steady-state position. Simulation results show that the proposed control law is very effective. The research of this paper may help to maintain the power system’s security operation.