Magnet power supplies of the J-PARC MR. High-accuracy power supplies for high-power accelerators

The Japan Proton Accelerator Research Complex (J-PARC) began operations in 2008. The main ring (MR) of the J-PARC provides proton beams to two facilities: one is for the neutrino beam line, and the other is for the hadron experimental hall. A MR beam power of 470 kW has been achieved on the neutrino beam line. For high-power beam production, magnet power supplies require high accuracy for the output current to follow instructed current values. In order to improve the accuracy, we modified the magnet power supplies and electrical wiring between the power supply and magnets. Symmetrical wiring is essential to improve electric current tracking and reduce current ripples. (author)