A New Repetitive Flat-top Pulsed Magnetic Field Power Supply for Gradient Driver in MRI

Abstract

For the power supply of the gradient coil set in Magnetic Resonance Imaging (MRI) system, i.e., the gradient driver, a highly stable flat-top current with a fast-rising stage and fast falling stage is needed. This article proposed a novel topology using partial power processing to generate the current repetitively, which can significantly reduce the switching frequency of all switching devices compared with conventional topologies, resulting in less switching loss and higher stability. Topology analysis and parameter design have been made for a 2000A peak current, 20ms flat-top, 500µs rising time, 1000 ppm stability application situation. And simulation results verified the proposed topology's superiority in lower switching frequency.