Mathematical Problems in Engineering
Volume 2009 (2009), Article ID 495360, 23 pages
Research Article

Approximate Algorithm for Determining Pulse Edges of a PWM Inverter Based on Natural Sampling

1Faculty of Transport and Traffic Engineering, University of Belgrade, Vojvode Stepe 305, 11000 Belgrade, Serbia
2“Mihajlo Pupin” Technical Faculty, University of Novi Sad, Djure Djakovica bb, 23000 Zrenjanin, Serbia

Received 8 November 2008; Revised 3 April 2009; Accepted 20 April 2009

Academic Editor: Mohammad Younis

Copyright © 2009 Dragutin Kostić and Vladimir Šinik. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The paper presents a new algorithm for determination of pulse edges of a modulated wave of a PWM voltage inverter which offers a possibility that natural sampling is realized with an arbitrary accuracy without applying an iterative procedure. The basic idea is to express the angles which determine pulse edges of the modulated signal as polynomials of amplitude modulation index. Geometric interpretation of sampling of the polynomial algorithm is identical with the geometric interpretation of natural algorithm, but the transcendental equation whose solution defines pulse edges of the modulated signal is replaced by a simple procedure of finding values of a polynomial whose coefficients are determined in advance by an exact procedure. This approach gives the possibility of digital implementation of polynomial sampling method using the low-cost microprocessor platforms.