IFSMTF power supply regulator

The high-current, low voltage power supplies for the International Fusion Superconducting Magnet Test Facility at Oak Ridge National Laboratory has been redesigned to eliminate stability problems caused by limiting action and related system dynamics. This paper describes the redesign, simulation, and testing of the power supply regulator for a 2-H, 15,000-A superconducting coil. Included in the paper are circuit models, frequency domain block diagrams, and CSMP simulations of the regulator. The regulator consists of an inner voltage loop and an outer current loop and is provided with adjustable voltage and current limits. The simulation includes a nonlinear function to characterize the gate drive and rectifier units of the power supply. Experimental data demonstrating the performance of the regulator are included for comparisons with the simulation