| Abstract: | Angle stability problems are well known in almost every power system in the form of transient instability or undamped system oscillations. Unlike the frequency stability problems, angle stability has not yet been treated as a control problem, due to limitations in measurements, communication and power equipment. However, new technologies employing satellites, optical fibres and power electronics have overcome these physical problems. The report demonstrates how equipment using power electronics for fast angle control can give a single line the characteristics of a multiple-line interconnection. Further, it is shown how this can completely change the dynamic behaviour of a power system, and in the ideal case even eliminates oscillations following small disturbances. The use of angle control to give DC links the desired properties of AC links is also described. |
