Frequency Response Methods for Tuning Stabilizers to Damp out Tie-Line Power Oscillations: Theory and Field-Test Results

During the past ten years a number of authors have put forward techniques for tuning power system stabilizers (PSS) in the literature. Some of these techniques have been tested in on-site applications and others have been evaluated using simulation techniques. This paper describes a theoretical basis, and supporting experimental evidence from tests performed at a power plant, for tuning power system stabilizers using frequency response techniques. By using the method described in this paper, the power system analyst is able to obtain an approximate measure of the amount of damping that can be expected from the stabilizer in damping out tie- line power oscillations. The tests were conducted on the inter- tie between the Alberta and British Columbia Hydro power pools. Test results indicated a direct correlation between the improvement in the electric power damping as observed by field tests and that predicted by theoretical means. Although the method suggested in this paper has general application to power system stabilization for local mode damping and inter- tie damping it was applied to the specific case where the tie- line power was used as a feedback signal to the stabilizer.