Research on high-voltage pulsed power supplies for accelerator applications with advanced SiC devices

A number of high-voltage pulsed power supplies used in the accelerator system used discharge tubes such as thyratrons, because of high-voltage more than several tens kV, large currents more than several kA, fast rise time less than several tens ns. However, these discharge tubes had many shortcomings such as short lifetime, low repetition frequency, necessity of auxiliary power supply, poor stability. The performance of the accelerator had remarkably deteriorated by the discharge tube. In recent years, due to the rapid development of SiC semiconductor devices, the voltage and current of the device have been increasing year by year. In addition, as a result of various developments such as the MARX circuit, the LTD circuit, the matrix circuit and the SOS circuit, the circuit configuration operating a large number of semiconductor devices in series and parallel has been advanced. All high voltage pulse power supplies have become possible to realize by using semiconductors only. Then the performance of the accelerator has also been significantly improved. We have conducted a systematic research on the selection of the optimum pulse power system according to the application. A part of this research was conducted as a joint project 'Tsukuba Power Electronics Constellation (TPEC)' project. (author)