Interval Fuzzy-PSS Using Gauss-2 Membership Function to Enhance Small-Signal Stability

Abstract

Interval type-2 fuzzy (IT2F) model develops to substitute conventional control in power system (PS). The PS is operated to serve the consumer according to load demand. Load fluctuation on the PS is a real situation and can't be avoided. The load fluctuation causes rotor oscillation on machine. Moreover, instability problem can occur if this oscillation is not quickly to damp. The IT2F-based algorithm is developed to replace conventional power system stabilizer (PSS) function. The IT2F is implemented in this research because it simple and not need exactly calculation of plant model. A single machine and multi-machine power systems are applied to assess the performance of the IT2F-PSS. This IT2F-PSS is constructed by two inputs and an output. Three membership functions (MF) Gauss-2 type are used for respective inputs. Five MFs constant type are used for output. The values of fuzzy parameter are tuned properly based on the knowledge and experience the fuzzy developer. Simulations on the case studies provide enhancement the response of rotors speed and angle. The IT2F-PSS responses are assessed on peak overshoot and settling time.