An economical four-quadrant GTO converter and its application to DC drive

A four-quadrant converter employing a single six-GTO bridge and four thyristors as reversing switches is described. Such a four-quadrant converter is economical compared to a dual converter employing two bridges, each with six GTOs. A four-quadrant DC drive employing the proposed converter and closed-loop speed control with inner current control loop is also presented. The controllers are designed using symmetric optimization. The experimental results are given for the steady-state and transient response of the drive. A comparative study of the present four-quadrant drive and one reported earlier is also presented.<<ETX>>