Richness of modern power systems with high- performance rapid devices of automatic control, in particular, excitation controllers with power system stabilizers, and also more and more wide use of self-acting counter-emergency control operating on the vapor turbines has provided an opportunity of the complete use of transmission lines' capacity on conditions of aperiodic and a transient stability and intensive suppression of electromechanical oscillations. For the actual purposes of power stations operation in an electric power system it is necessary to perform multivariate computations for a justification and sampling of stabilization channels tuning of excitation controllers. The methods of choosing of the optimal adjustment of power system stabilizers of generators' automatic voltage regulators is given in this paper.