Gain Scheduled-Based Analytical Structures of Fuzzy PI Controllers
Satyavir Singh · SSRN Electronic Journal · 2012
The paper presents new analytical input and output relation for gain-scheduled fuzzy Proportional-Integral (PI) controllers that use Zadeh AND operator with symmetric trapezoidal input fuzzy sets and skewed trapezoidal input fuzzy sets. These are derived overall input space division for symmetric and skewed trapezoidal input fuzzy sets with three membership functions in each input for gain scheduled fuzzy PI controllers (Lee, 1990). The rule-base for tuning the output scaling factor is defined on error and change in error of the controlled variable using the symmetric trapezoidal and skewed trapezoidal Membership Functions (MFs). A self-tuning scheme for Fuzzy Logic Controllers (FLCs) with output Scaling Factor (SF) is adjusted by fuzzy rules according to the current trend of controlled process (Palm, 1992). Tuning of the output scaling factor plays an important role in this self-tuning scheme. To show the effectiveness of gain scheduled fuzzy PI over fuzzy PI controller computer simulations for first order and second order time delay systems are presented.