Damping of Oscillations in Multi-machine Integrated Power Systems Using Hybrid Fuzzy Strategies

The design & development of a fuzzy logic controller using UPFCs to damp out the oscillations in FACTS based integrated multi-machine power system when faults takes place at different buses (one fault at a time) is presented in this paper. The multi-machine system consists of 3 generators, 3 transformers, 9 buses, 4 loads & 2UPFCs. 3 Simulink models are developed with & without the hybrid controller by considering the occurrence of one fault at a time near each generator. The 3 phase to ground symmetrical fault is made to occur near the first generator for 200 ms in the model 1, next at the second generator in model 2 & finally at the third generator in model 3. Simulations are performed with & without the controller. The 3 models are compared for the effectiveness of the fault occurrence near each of the generators. The digital simulation results show the effectiveness of the method presented in this paper.