Type tests of JT-60SA Fast Plasma Position Control Coil (FPPCC) power supplies

In JT-60SA, Fast Plasma Position Control Coils (FPPCC) PSs allow controlling the vertical position of the plasma during a plasma shot, to prevent a Vertical Displacements Event (VDE). The FPPCC PSs have to react very fast to plasma movements. For this reason, an open loop feed forward voltage control is adopted in order to achieve a fast control of FPPCC PSs. The characteristics of the PS are: 4-quadrant AC/DC converter 12-pulse, DC load voltage ±1000 V and DC load current ±5 kA. The design of the FPPCC converters has been validated by a simulation model, finalizing the performances and dynamic behavior of voltage response. After the completion of the realization phase, the testing phase has been carried out in accordance to the IEC60146 Standards and this is the focus of the paper. The tests performed have pointed out a good dynamic behavior of the FPPCC converter in open loop feed forward voltage control, for a reference voltage step of 1kV, the rise time of output voltage is 2.88 ms, confirming outcomes achieved by simulations.