Realization of a “Band-Stop” device to damp inter-area oscillations with intervention into the turbine governor

We can observe in all electrical systems in the world, cc. 0.2,..., 0.35 Hz oscillations in state variables in steady state operation. The amplitude of these - so called inter-area oscillations - is growing going away from the centre of a large electrical power system. In the UCTE (European) system in the centre (near the German-French border) the amplitude of oscillations in frequency deviation time function is less then 2 mHz and near the borders (at present: Greece, Poland, Portugal, Romania, etc.) greater than 6 mHz, in steady state operation. Our ten years´ experience has shown that PSSs, realized with ldquoconventionalrdquo stages are not efficient in inter-area frequency domain. In addition, these instruments have a disadvantage: there are frequency intervals in the operating range of PSSs in which the PSSs increase the amplitude of active power oscillations and reactive, too; which are exported into the network. In our former activity we presented the model investigation to solve the problem by intervention into the turbine governor [1], [2]. In this paper the realization of the method is shown.