IGBT  (Insulated Gate Bipolar Transistor), insulated gate bipolar transistor, is a composite fully controlled   Voltage -driven power semiconductor device composed of BJT (bipolar transistor) and MOS (insulated gate field effect transistor), which also has   MOSFET   The advantages of high input impedance and low on- Voltage   drop of GTR. The saturation voltage of GTR is reduced, the current-carrying density is high, but the driving current is large; the   MOSFET   driving power is small, the switching speed is fast, but the conduction 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 reduced saturation voltage. It is very suitable to be used in converter systems with a DC voltage of 600V and above, such as AC motors, frequency converters, switching power supplies, lighting circuits, traction drives and other fields. In layman's terms: IGBT is a high-power power electronic device.