The dual converter with circulating current mode can be used to meet the high-power requirement of the fourquadrant dc magnet power supplies. The dual converter has been used mostly in dc drive systems without the circulating current. In this paper, the closed-loop output voltage regulation is presented for the dual converter with circulating current mode, used in the application of four-quadrant dc magnet power supplies. The closed-loop control is designed to improve the dynamic response of the dual converter and to provide the required regulation. The stability analysis of the closed-loop system is presented for the effect of time delay associated with the sample-and-delay nature of the dual converter gating.