Membership function distribution effect on fuzzy logic controlled induction motor drive

The paper investigates systematically the effect of membership function distribution in the fuzzy control of an induction motor drive. Triangular type membership function has been considered only in all the studies. In the beginning, even or symmetrical membership functions have been used with increasing number of fuzzy sets for all the variables. Then, asymmetrical (both convergent and divergent types) membership functions have been used in sequence for the fuzzy variables. Finally, asymmetrical membership functions with different degrees of asymmetry have been mixed for all the variables with the objective of achieving optimum performance of fuzzy control. In all these cases, fuzzy control performance has been evaluated extensively for a speed-controlled induction motor drive with indirect vector control in the inner loop.