Chams-Eddine Feraga  , Abdallah Bouldjedri  , Ali Yousfi  , 
    Uniform Pulse-Width Modulation (UPWM) Three-Phase Four-Quadrant ac-dc Converter-Fed DC Motor Drive,
    Asian Journal of Information Technology,
    Volume 5,Issue 7,
    2006,
    Pages 761-766,
    ISSN 1682-3915,
    ajit.2006.761.766,
    (https://makhillpublications.co/view-article.php?doi=ajit.2006.761.766)
    Abstract: A three-phase ac-dc GTO thyristor converter-fed dc motor is studied in detail, employing an Uniform Pulse-Width Modulation (UPWM) scheme and verified by computer simulation. It has been found to offer good performance. It offers only two-quadrant operation because of the unidirectional current conduction nature of GTO’s. A four-quadrant converter that employs a single six-GTO bridge converter and four thyristors serving as a reversing switch is described. The four-quadrant dc drive employing the proposed converter and the control structure including speed and current control loop is also presented. Simulation results with a separately excited dc motor are given for steady-state and transient responses of the drive. The simulation results are shown to be in good agreement with the theory.
    Keywords: GTO;ac-dc converter;pulse with modulation;UPWM;DC drive