SMES for Electric Power Compensation of the J-PARC High Intensity Proton Synchrotron

A new proton accelerator complex for a high intensity beam (Japan Particle Accelerator Research Complex-J-PARC) is under construction at the Tokai campus of Japan Atomic Energy Research Institute as a joint project between KEK and JAERI. The accelerator complex is composed of a 600 MeV linac, a 3 GeV rapid cycling synchrotron, and a 50 GeV main synchrotron. In Phase I, the main synchrotron will be operated at energy of 40 GeV with pulse operation. The proton energy is to be increased up to 50 GeV in Phase II, and a large amount of pulse electric power, which is +115 MW and -55 MW peak-to-peak with 3.4-second repetition, will be demanded. Such large pulse power will give un-allowed disturbances to the power network. Some means will be required for compensating the pulse electric power and reducing the disturbances. A SMES system is one of the promising means. We have studied a SMES system for this purpose, designed the SMES coils using a force-balanced coil and a solenoid with a capacity of 100 MJ/55 MW, and proposed a new circuit scheme. The cost estimation of the SMES system is also described