Abstract

Magnetic Resonance Imaging (MRI) is vital equipment in modern hospitals and an MRI helps doctors and patients to diagnose multiple diseases. In an MRI equipment, a magnet is one of the key parts which generates a constant magnetic field. There are two methods to produce a static constant magnetic field in a modern MRI system. One method uses a permanent magnet and another one uses a superconducting coil to produce the magnetic field. In modern designs, most high-end MRI equipment use superconducting coils to generate a static magnetic field. The current in superconducting coils can go up to 500 A or more. For driving a superconducting coil, MRI designers need to design a power supply with high output current capacity. This application note proposes a design to design such a power supply to drive the superconducting coil of an MRI equipment. Since there are lots of books and articles to discuss the power circuits or topology for power supplies, this application notes mainly focus on discuss the controller system design.