Nonlinear phenomena analysis in thyristor

The systematic failure theory of the power electronic devices has always been absent, and the device characteristic of internal dynamics is often been neglected. For the better explanation of nonlinear phenomena in power electronic devices, this paper researched the typical device of thyristor in detail. In the first instance, whether frequency change or gate current change, the simulation and experimental results all validated the inherent chaotic phenomena of thyristor. In order to analyze the mechanisms, based on the energy-band theory of semiconductors, discussed the corresponding relationship between energy-band and excess carriers. Meanwhile, compared the energy-band diagrams of thyristor under the individual states, and analyzed the influence on the space charge width and excess-carrier concentration by the magnitude of applied voltage. Chaos mechanisms during the two different conditions were also clarified by energy-band theory at the first time. Finally, this paper presented the possible effect to the device and circuit.