An analytic method for stabilization of the unstable orbits of a complex system is applied to the problem of ferroresonance in power systems. The method is based on the feedback control theory proposed by Pyragas (1992). Simulation results are presented illustrating transitions from unstable, chaotic, to stable, periodic, orbits. The stability was evaluated using the largest Lyapunov exponent. In this way, an efficient approach to the damping and control of the ferroresonant chaotic oscillations, which can arise in high-voltage terminal equipment, is presented.