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

A four-quadrant gate turn-off (GTO) power 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 motor drive employing the proposed converter and closed-loop speed control with an inner current control loop is also presented. The controllers are designed using symmetric optimization. Experimental results with a 3 HP DC motor are given for steady-state and transient responses of the drive. A comparative study of the present four-quadrant drive and the one reported earlier is also presented.<
>