A study on the application of thyristor-controlled static phase shifters (SPS) to stabilize the common-mode torsional oscillations occurring in a series-capacitor compensated power system is presented in this paper. The IEEE Second Benchmark Model, system-2, which has two non-identical turbine-generator sets connected to an infinite bus through a series-capacitor compensated transmission line, is employed to investigate whether the possible unstable subsynchronous resonance (SSR) modal interactions can be suppressed by the proposed damping scheme. The torsional interactions due to one of the torsional oscillating frequencies in one machine is nearly the same as the one in another machine. In order to effectively suppress the unstable torsional modes in the studied system, a systematic approach based on modal control theory is proposed and a set of static phase-shifter controllers (SPSC) is designed. The effectiveness of the proposed damping scheme is demonstrated by means of frequency-domain approach based on eigenvalue analyses and time-domain approach based on non-linear model simulations. The simulations results show that the static phase shifters and the designed controllers can be applied to suppress common-mode torsional interactions.
|Number of pages||8|
|Journal||European Transactions on Electrical Power|
|Publication status||Published - 1997 Dec 1|
All Science Journal Classification (ASJC) codes
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering