Development of a General Tokamak Circuit Simulation Program and some application results to the JT-60 power supply system

This paper describes the General Tokamak Circuit Simulation Program (GTCSP) developed for designing the power supply system of a large nuclear fusion device JT-60. GTCSP can deal with synchronous generators, phase delayed transformers connected to thyristor converters, inductively coupled passive coils and their combination. Since the GTCSP code is designed for limited purposes, it has the advantages of a smaller number of input parameters and shorter computation time. The time step of the simulation is automatically adjusted according to the change of power converter switching mode, and this function suppresses switching noises. A program overview and some application results are presented.