Modeling a three-phase micro hydropower plant prototype using Takagi-Sugeno fuzzy approach

This paper presents a Takagi-Sugeno (TS) fuzzy model of a three-phase micro hydropower plant (MHPP) prototype. It represents the system as an interpolation between local models. Each local model is linear system validated around an operating point. The Three-phase MHPP behavior varies with load variations and water flows. These matters create difficulties to have an exact model close to real system. This paper proposes a multi-model approach for modeling the overall behavior of the three-phase MHPP based on the identification of a simple approximation of first and second order systems around several operating points (different water flows and load variations). The results show that the approximation results of second order system have high accordance with the real system responses. This approximation offers more opportunities to synthesize suitable robust controllers for MHPP based on digital calculators, especially when the proposed approach is used in closed loop. Besides, the paper also presents a new load-frequency structure for three-phase MHPP. This structure is controlled by a simple Proportional Integral (PI) controller. The developed TS fuzzy models were experimentally validated taking into consideration various working conditions.