Used in medium to high capacity power applications such as switching power supplies, motor controls and induction cookers.
The IGBTs are also used in motor drives for electric vehicles, inverter air conditioners, inverter refrigerators, and even as audio drivers for high-wattage audio amplifiers.
The IGBTs are characterized by their ability to switch quickly in high-power situations, so they are often used in conjunction with pulse width modulation (PWM) and low-pass filters.
Because of the semiconductor component technology, semiconductor raw material quality enhancement, IGBT unit price is getting cheaper and cheaper, and its scope of application closer to the scope of household products, and no longer just a high power level of power system applications.
Electric vehicles and hybrid vehicles such as motor drive is the use of IGBT components, Toyota's second-generation hybrid Prius II will use 50kw IGBT module inverter to control the two groups of AC motor/generator in order to make the conversion of power energy with DC battery packs.
Expanded Information:
Blocking and Latching of IGBTs:
When a reverse voltage is applied to the collector, a reverse voltage is applied to the collector. is applied a reverse voltage, J1 becomes reverse biased and the depletion layer expands into the N-region. This mechanism is important because an effective blocking capability cannot be achieved by reducing the thickness of this layer too much.
On the other hand, if the size of this region is increased too much, the voltage drop will be successively increased. The second point clearly illustrates the reason why the voltage drop of an NPT device is higher than that of an equivalent (IC and speed identical) PT device.
When the gate and emitter are shorted and a positive voltage is applied to the collector terminal, the P/N J3 junction is controlled by a reverse voltage. At this point, it is still the depletion layer in the N-drift region that is subject to the externally applied voltage.
The IGBT has a parasitic PNPN thyristor between the collector and emitter, as shown in Figure 1. Under special conditions, this parasitic device conducts.
This phenomenon increases the amount of current flow between the collector and emitter, reduces the ability to control the equivalent MOSFET, and usually causes device breakdown problems.
The thyristor conduction phenomenon is known as IGBT latch-up, specifically, the causes of this defect vary from one another and are closely related to the state of the device. Typically, the main difference between static and dynamic latch-up is as follows:
Static latch-up occurs when the thyristor is fully conducting. Dynamic latching occurs only at turn-off. This particular phenomenon severely limits the safe operating area .
To prevent the harmful phenomenon of parasitic NPN and PNP transistors, it is necessary to take the following measures: Prevent the NPN from being partially turned on, change the layout and doping level, respectively. Reduce the total current gain of the NPN and PNP transistors. In addition, the latch-up current has an effect on the current gain of the PNP and NPN devices, and therefore it is also very closely related to the junction temperature; in the case of junction temperature and gain increase, the resistivity of the P-base region rises, destroying the overall characteristics.Therefore, device manufacturers must take care to maintain a certain ratio between the maximum collector current value and the latch-up current, usually a ratio of 1:5.
Baidu Encyclopedia-IGBT