A Comparative Analysis of Controller Methods for DC Servomotors Under Load Variations

A servomotor is a type of rotary actuator that uses an input signal to precisely regulate position, acceleration, and velocity. Given the precise regulating requirements, it is crucial to operate this motor under a variety of load conditions. A simulation model of a PID controller for variable speed in both constant load and variable load was developed using MATLAB for DC servomotor (DCSM). The simulation aims to design an optimal control system to control speed, torque, current, and position under two scenarios: one with a constant load and another with a variable load. A comparative analysis of the three controlling methods was then analyzed. For a constant PID controller, the values of P, I, and D remain unchanged even when the load varies, but for adaptive PID, P, I, and D vary according to the load demand. The motor performed significantly better with constant PID and adaptive PID controller than the type without PID, considering settling time, rise time, and peak time. Notably, the adaptive PID has shown a promising performance by effectively reducing settling time and transitional torque, highlighting its advantages for dynamic systems.