Application of PID-type iterative learning control for DC motor

Iterative learning control is a new control technology, which is a branch of intelligent control theory and particularly suitable for the controlled object with repetitive motion. In this paper, a PID-type iterative learning control for DC motor based on the characteristics of repeating motion of DC motor was proposed and the convergence of iterative learning control algorithm was analysed. The input of controlled system in current cycle was amended by the error achieved between the system output and the desired trajectory in previous iteration. It was tested that PID-type ILC had good performance and stability through a large number of simulations and the experiments of the velocity tracking are done by MATLAB software. The results showed that the velocity tracking precision of DC motor was higher and the error was smaller with the increasing number of iterations. The velocity tracking error was close to zero. It was also shown that the motor could fully track the given desired trajectory in some certain iteration. It was also revealed from simulation results that the proposed control strategy was valid and effective for the DC motor.