Design and Operation of a 42-MW Highly Stabilized Power Supply at the CHMFL

The 42-MW highly stabilized power supply system, developed by the High Magnetic Field Laboratory, Chinese Academy of Sciences (CHMFL), successfully energized a newly designed water-cooled resistive magnet, achieving a world-record magnetic field of 42.02 T in September 2024. This system is composed of a newly developed 14-MW power supply unit in parallel with an existing 28-MW unit. The 14-MW power supply integrates high-voltage static var generator (SVG) technology, which replaces the conventional power factor correction method using fixed-capacitor banks, enabling dynamic reactive power compensation and stabilization of the grid voltage. Additionally, a novel series-connected active filter was developed to further reduce current ripple, featuring lower power losses, a more compact size, and easier control. This paper provides a detailed description of the design, testing, and operational data analysis of the 42-MW power supply system for the 42.02-T resistive magnet. Furthermore, future upgrading plan for the system are discussed.