Photocopier PID controller with iterative error compensation

This paper describes an implementation of a proportional-integral-derivative (PID) controller with an iterative error compensator for a DC brushless motor to improve the quality of a photocopier. The parameters of the iterative error compensator are determined by using particle swarm optimization algorithm. The proposed controller reduces the effects of repetitious unknown load torque on the DC brushless motor by compensating the motor torque based on the motor velocity from the previous sequences. The proposed controller is compared to a PID controller under various load torques.