Software controlled pulse-width modulation

Abstract

After a brief introduction, on the rapid advance in the related technologies used in implementing all types of pulse width modulation, the specific advantages of this technique are described in detail. The description of simple techniques used to produce cruder forms of PWM are mentioned, while emphasis was laid on the more sophisticated types of PWM (as those implemented in this project), which better enhance the general advantages described. The three main different modes of PWM are then covered in detail. The design of two software programs (in C language) implementing two main forms of PWM (natural sampled and regular sampled PWM) written for the IBM computer are then presented. The information used in the program to simulate the respective type of PWM, is described and it is shown that the program coincides with the theory behind that form of PWM. A design of an interface to the computer so as to produce in real time the information obtained in the software programs is then presented, with details of how the interface could be used to (i) simulate the PWM form being simulated in the software and (ii) how the interface could be used to drive a three-phase inverter to produce PWM for industrial use.