Converter Based DC Motor Speed Control Using TMS320LF2407A DSK

Abstract

This paper deals with real time DC motor speed control, using the low-cost new generation TMS320LF2407A digital signal processor. A PID controller is designed using MATLAB functions to generate a set of coefficients associated with the desired controller characteristics. The controller coefficients are then discretised and included in an assembly language or C program that implements the PID controller. Code composer studio is used to load and run the PID controller to achieve real time control. Furthermore, the PID parameters can be adjusted while the motor is running, so that the online adjustment is achieved. Speed control is investigated on a DC motor with speed feedback. According to the error in speed, followed by PID action DSP processor changes the duty cycle of the PWM, which is given as the input to the buck converter. Results show the improvement of system outputs as expected with a PID controller, with actual system outputs matching theoretical calculations. Since cascaded buck converter is having the added advantage over DAC that it can be principally extended for motors of higher ratings only by changing the component values of buck converter