THE FUZZY CONTROLLER SYNTHESIS WITH A SPECIFIEDMULTI-DIMENSIONAL STATIC CHARACTERISTIC

摘要

Fuzzy controller is a multivariate nonlinear static link. For the synthesis of fuzzy controller it is sufficient to determine its desired static characteristic and adjust it so that it coincides with the desired. This paper deals with the stages of the fuzzy controller synthesis by the desired static characteristic: the formation of input and output signals linguistic variables; production rules system synthesis. Formation of linguistic variables, the selection of aggregation, accumulation and defuzzification algorithms is determined by expert based on the control object characteristics, personal experiences and expert’s preferences.For the fuzzy controller synthesis by the desired characteristics a reference values table is created on which basis the synthesis of the production rules base takes place. Using production rules with a double consequent allows synthesizing fuzzy controller with the required accuracy. The consequent truth degree is determined graphically.To impart the dynamic properties to the fuzzy controller at its input the time derivatives of input signals or additional feedbacks can be fed. Instead of the time derivatives the increment input signal over a time period can be fed.The fuzzy controller static characteristic is a smoothly varying multi-dimensional surface. These properties improves the qualitative indicators of regulation.High accuracy, smooth nonlinear multidimensional characteristics, dynamic properties, ease of synthesis allow using this controller not only in technological process control systems, but also in solving simulation problems and creating multidimensional nonlinear dependencies.