Si-SiC based switching power amplifiers for MHD modes control in fusion experiments

The paper, after an overview of the typical requirements of Power Supply (PS) systems to control MagnetoHydroDynamic (MHD) instabilities and of technological solutions adopted in some present fusion experiments, reports on the last progress in the production of SiC power devices, which features can be interesting for this type of applications. The advantages of the SiC devices with respect to the Si ones include lower switching losses, higher switching speed, higher operating junction temperature and a higher voltage capability. The paper reports on the case of the PS system for RWM control in the JT-60SA satellite tokamak, where analyses showed the difficulty of satisfying the demanding requirements in terms of high current bandwidth (3 kHz) and short latency (<;50 μs), with a simple H-bridge topology adopting standard IGBT. On the contrary, the use of Si-SiC IGBT with the same topology can allow meeting the specifications, as demonstrated by the development and test of such a power amplifier, rated for 300 Apk and 240 V.