IGBT (insulated gate bipolar transistor), insulated gate bipolar transistor, is composed of bipolar transistor (BJT) and insulated gate field effect transistor (Metal Oxide Semiconductor, MOS) has the advantages of high input impedance of metal-oxide-semiconductor field-effect transistor (MOSFET) and low on-voltage drop of Giant Transistor (GTR). The saturation voltage of GTR decreases, and the current-carrying density is high, but the driving current is large; The driving power of MOSFET is very small, and the switching speed is fast, but the turn-on voltage drop is large and the current carrying density is small. IGBT combines the advantages of the above two devices, with low driving power and low saturation voltage. It is very suitable for converter systems with DC voltage of 600V and above, such as AC motors, frequency converters, switching power supplies, lighting circuits, traction drives and other fields.