Interval Type-2 fuzzy logic controller design for the speed control of DC motors

Abstract

In this paper, an optimal interval Type-2 Fuzzy controller is designed for the speed control of DC motors. In this way, first, the importance and position of Type-2 fuzzy systems are mentioned. In addition, some properties of Type-2 operators are investigated as well as the properties of membership degree of Type-2 fuzzy sets. A comparison between different parts of Type-1 and Type-2 fuzzy systems, such as fuzzifier, fuzzy inference engine, rule-base and defuzzifier is given. Finally, an Interval type-2 Fuzzy logic controller is implemented for the speed control of DC motor for the cases of series and shunt. The motor is considered under both the load disturbances and disturbance free conditions. The obtained results for different conditions are compared in tables and figures. The results show that in the disturbance free case, both controllers have acceptable performance, however, when the system is affected by disturbance interval Type-2 controller has better performance.