Speed Control of a Variable Loaded DC Motor by Using Sliding Mode and Iterative Learning Control

Abstract

In this paper, speed control of a DC Motor with time varying loaded is performed by using sliding mode control (SMC), classical PID control and iterative learning control (ILC) methods. SMC is a robust nonlinear control method which has insensibility against to external disturbing effects and parametric variations of system. On the other hand, a control method of ILC provides an excellent performance on tracking. In the iterative learning PID (IL-PID) controller, the parameters of PID are automatically adjusted by using the algorithm of iterative learning. In this study, firstly, a DC Motor is modeled by using real data. Secondly, controllers which are an iterative learning PID (IL-PID), SMC-based and classical PID are designed and tested. Moreover, performance analysis of these controllers is done for load changes in the time interval. According to obtained results, the output of SMCbased system converges quickly to the reference value and the system gives the fastest response when changing of load occurs. Another result of this study is that the steady state error based on the learning success of ILC is decreased by IL-PID controller. The novel part of this study is that the comparison of these types of controllers is firstly made with this study. 

Fuzzy-PID based control scheme for PMDC series motor speed control

“…Fuzzy controller is designed with minimum number of rules so that controller response is faster with more optimized results than the PID controller. Fuzzy-PID controller is set to be designed with nine (9) rules to obtain a better control strategy than PID and FLC. The loading time greatly influences the settling and rise times of the controller.…”

“…Proper tuning of PID coefficients helps obtain an optimal performance of the process. There are several other method to deal with such nonlinearitties (8,9) . Fuzzy logic control (FLC) is a nonlinear control scheme which provides a way of computing uncertain values.…”

“…FLC is derived from the Fuzzy set theory which employs a way of estimated reasoning similar to human-like decisions. FLC has an advantage over conventional PID controller that it can perform nonlinear control actions (9,10) . It consists of linguistics terms and IF-THEN type of rules that define a certain control action.…”