Dual configuration, dual setting, digital power system stabilizer-simulation and tuning experience at Manitoba Hydro

This paper describes a digital power system stabilizer which can automatically switch between two different sets of settings and operate as an electric power input type and an integral-of-accelerating power input type. The requirements for such a stabilizer along with techniques to facilitate its implementation on two hydraulic units which are switchable between an isolated AC system feeding an HVDC double bipole and a parallel, relatively weak, 230 and 138 kV AC transmission system, is provided. Stabilizer tuning based on load modulation is presented. Results from eigenvalue analysis and dynamic stability studies demonstrate the effectiveness of this stabilizer in damping both inter-area and inter-plant electromechanical modes, as well as reducing the undesirable effects of low gate mechanical torque oscillations.