Research on the application of GaN HEMT in the fast corrector power supply system of HALF

The fourth-generation synchrotron radiation source, Hefei Advanced Light Facility (HALF), requires stricter beam stability. Consequently, the magnet power supply used for beam orbit correction must achieve faster response times and higher output accuracy. The use of new-generation semiconductor power devices, such as Gallium nitride high-electron-mobility transistors (GaN HEMTs), provides higher switching frequencies and smaller sizes. In this paper, a fast-response corrector magnet power supply based on GaN HEMT is designed and introduced. The power supply employs a low-power, high-performance Microcontroller Unit (MCU), specifically developed for power supply applications, as the main controller. The prototype is built on a 210 mm × 80 mm printed circuit board (PCB). With a load inductance of 1 mH, the response bandwidth reaches 11 kHz, and the long-term stability is better than 20 Parts Per Million (ppm), with an output resolution of 5 ppm. This ensures beam orbit stability, thereby improving the performance of the HALF light source.