Application Research Of IGCT

IGCT which is developed from GTO combines the advance features of both GTO and IGBT, with the advantages of high switching-off voltage, large turn-off current, high switching frequency, low losses, and high reliability. The application investigation has been made in order to explore IGCT' s application possibility in the electric traction field of our country. The aim of the research is at mastering its application characteristics, investigating the influence of circuit parameters to the application performance, optimizing the circuit design. The paper introduces the performance parameters and the fundamental principle of gate drive circuit, and compares the features of IGCT, GTO and IGBT. Deep research has been made from multi-aspect to the application circuit by means of combining together theoretical analysis, computer simulation and experiment. On the aspect of experiment, the investigation has been carried out from simple to complicated, i.e. started from the single pulse and double pulses test of phase module, and then to consecutive-pulse chop test, and then to three phase inverting test. The influence of stray inductance in the module circuit to turn-off transient over voltage of IGCT has been investigated systematically, the surge current calculation has been done by simulation, and the short circuit failure once occurred in experiment has been analyzed by computer simulation, reproduced the breakthrough failure happened in experiment by means of simulation.Under the test conditions of Ud=2800V and 350Hz switching frequency, the current in three phase inverting test reached to lOOOAr. m. s, which can fully meet the requirements of 350km/h EMU with 2600V link voltage and 950Ar. m. s output current, and shows the ground-base test converter has been developed successfully.