A NOVEL DESIGN OF A FUZZY COORDINATED SSSC CONTROLLER FOR INTEGRATED POWER SYSTEMS

In this paper, a novel design and development of a fuzzy logic controller using static synchronous series compensators (SSSC) to damp out the swinging oscillations in a FACTS based integrated multi-machine power system when a three-phase line to line ground fault takes place at one of the generators in the power system is proposed. The multi-machine power system considered consists of three generators, three inductive transformers, nine buses, four loads and two POD based SSSC fuzzy coordinated controllers. Oscillations in power systems have to be taken a serious note of concern when the fault takes place in any part of the system; else this might lead to the instability mode and shutting down of the power system. The hybrid combination of a fuzzy coordination scheme with a static synchronous series compensator is proposed in this paper to suppress the swinging oscillations upon the occurrence of a fault at one of the generator side, say near the first generator (i.e. between the first generator and the three-phase load). Simulink models are developed with and without the fuzzy control by considering the occurrence of a fault. Three types of faults are considered, as LLLG (Line-Line-Line to Ground), LLG (Double Line to Ground) and LG (Line to Ground) faults. These faults are made to occur for a period of 0.2ms and then cleared. Simulations are performed with and without the fuzzy controller during the fault conditions. The results are compared for the effectiveness of the fault occurrence and the controller. Finally, the conclusions are given. The digital simulation results observed show the effectiveness of the method presented in this paper.