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IGBT rectifier

IGBT rectifier

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Briefly of IGBT rectifier:

Through comprehensive analysis of the equivalent circuit to simplify explain cumbersome IGBT working principle and the role, and noted IGBT characteristics. It can be said, IGBT is a switching device either on or off, it combine both advantages of of MOSFET’s high input impedance and GTR’s low conduction voltage drop.

IGBT Rectifier constitution:

IGBT (insulated gate bipolar transistor), constituted of BJT (bipolar transistor) and MOS (insulated gate field effect transistor) composite full-controlled type voltage-driven power semiconductor devices, with high input impedance MOSFET and GTR’s low on-state voltage drop down. GTR saturation pressure drop, carrier high current density, but the drive current is large; MOSFET drive power is very small, fast switching speed, but large conducting voltage drop, the carrier density is small.
IGBT combines advantages of these two devices, the driving power is small and the saturation while voltage drop low. Very suitable for the DC voltage of 600V and above, variable flow systems such as AC motor, inverter, switching power supply, lighting circuits, traction drive and other fields.
Insulated gate bipolar transistor (IGBT) is the youngest one of high voltage switch family. A 15V high-impedance voltage source facilitate control current flow through the device which can achieve a lower control power to control the high current.

IGBT rectifier principle and action:

Simply to say, IGBT is a switch, either on or off, how to control its on or off, by the gate-source voltage, when the gate-source plus +12V (greater than 6V, generally take 12V to 15V) the IGBT conducting, gate source voltage is not applied or is applied negative pressure, IGBT turn-off, a negative pressure purpose is reliably shut off. No amplified voltage IGBT function, turn on can be seen as the wire, other as open circuit when disconnected.

IGBT rectifier conduct/insulation electricity:

IGBT has three terminals, namely, G, D, S, G and S ends apply voltage, the internal electrons transfer (characteristic of the semiconductor material, which is the reason why use semiconductor material as power electronic switch), originally correspondence of positive and negative ions, semiconductor material in neutral, but applied voltage, electrons under the influence of voltage, accumulation to one side, forming a layer of conductive channel, because the electron is electrically conductive, becomes a conductor . If remove applied both ends voltage of GS, this layer of conductive channel disappear, do not conduct electricity, and become insulators. This is pass of IGBT rectifier.

IGBT rectifier