Investigation of the effects of fractional and integer order fuzzy logic PID controllers on system performances

In this study, the effects of fractional and integer order fuzzy logic PID controllers on system performances are investigated. In that respect, linear and nonlinear fuzzy decision rule bases are taken into consideration. To be fair on comparison, the parameters of the controllers are all optimized using BBBC optimization algorithm according ITSE performance index. This investigation is done on second order linear system with time delay since many high order systems may be represented by this model. Moreover, further study is done on a nonlinear benchmark system. It has been observed that linear decision surface in both controllers generally gives better performance than nonlinear decision surface. It is concluded that nonlinearity of fractional operators is more effective than the nonlinearity produced by fuzzy rule base.