Research On The Design Of Fuzzy-Control Based PSS

Due to less inherent time constant and faster response of the big capacity generator, the adoption of static excitation system on it will bring about weakened or even negative damping effects, which causes the low-frequency oscillation (LFO) in the power system and will exert great disturbances on the stability of the power system.Aimed at wiping out the LFS in the one-machine-to-infinite-bus system with local load, a new research on the PSS designing is presented in this paper. It introduces the principle of fuzzy control on PSS to cope with the nonlinearity & unsteadiness of the power system.A new control approach based on fuzzy logic is presented and successfully applied to the generator stabilizer in this paper. The approach not only keeps the merits of the conventional fuzzy controller, but also conquers the shortcoming of the conventional fuzzy controller. The conflict between the sensitivity and the robustness in the conventional control is eliminated in the proposed method. In the conventional fuzzy controller design, the control rule wholly depends on the experience of experts. An approach to adjust the control rule and parameters is proposed here on the basis of the control effects. Theproposed method has been used to design a fuzzy power system stabilizer in this paper and improve power system dynamic stability consequently. Took the Manwan power plant in Yunnan as the prototype, the practical multimachine system was simplified as a one-machine-to-infinite-bus system, and a mathematical description model of it was produced to facilitate the whole process of the Fuzzy-PSS digital simulation ?analysis. The research showed that the fuzzy control-based PSS had improved the stability of the power system and upgraded the quality of the system control, which testified the effectiveness and feasibility of the research.