V-i characteristics - power semiconductor devices , Electrical Engineering

Assignment Help:

V-I Characteristics

 In the  normal  mode of  operation of an IGBT  a positive  voltage is applied to the collector relative to emitter. When  the gate is at zero potential with  respect to E no  collector current IC flows  for collector voltage VCE below the  breakdown level  VB. When VC < VB  and the gate voltage exceeds the threshold  value VGT, electrons  pass into the N- region ( base  of the P-N-p transistor).

1742_V-I Characteristics.PNG

                                                                        Figure V- I characteristics of IGBT

These electrons  lower the  potential of the N region  biasing the P+ - N_  junction thereby causing holes to be injected from  the P+  substrate into the N_ epi-layer region. The excess electrons and holes modulate the conductivity  N+ region which dramatically reduces the  on resistance of the device. With  zero gate  bins the forward characteristic  of  IGBT  shows  very low current (<1bA)  where it breaks up sharply to much larger current levels with only a slight  increase in voltage. The Vcharacteristics of IGBT  is shown  in figure  it show the relation  between  collector current  tc and collector to emitter voltage VCE  for different values of gate to  emitter  voltage VGE.

The junction J1 blocks reverse voltage. An IGBT  without  N+ buffer layer  has higher  reverse blocking  capability. Therefore  an IGBT  required  for blocking  high  reverse voltage  does not  have N+  buffer layer. The  reverse blocking voltage  is shown  as the VRM on the VI  characteristics. The junction J2 blocks the forward  voltage when the IGBT is off.

 

 


Related Discussions:- V-i characteristics - power semiconductor devices

Determine the parameters of the equivalent circuit, The no-load and blocked...

The no-load and blocked-rotor tests on a three phase, wye-connected induction motor yield the following results: • No-load test: line-to-line voltage 400 V, input power 1770 W,

Which realization requires the least number of gates, Q. Consider a 1-bit v...

Q. Consider a 1-bit version of the digital comparator shown in Figure. Note that the operation of this circuit is such that whichever output is 1 gives the desired magnitude compar

Methods of material handling, Q. Show the Methods of material handling? ...

Q. Show the Methods of material handling? Methods of material handling during operations and maintenance activities shall be considered for all facilities to ensure that the fi

Querying the gis, Querying the GIS: Interfaces which use the querying...

Querying the GIS: Interfaces which use the querying facility are available with the RDBMS. In the network-mapping environment, these give accurate and reliable information to

Coupling, advantages and disadvantages of direct and r c coupling

advantages and disadvantages of direct and r c coupling

Output waveforms for a differentiating circuit, Q. Discuss the output wavef...

Q. Discuss the output waveforms for a differentiating circuit. The output waveform from a differentiating circuit depends upon the time constants and shape of the input wave.Th

When mt2 and gate is negative, when MT 2 and Gate  is Negative In th...

when MT 2 and Gate  is Negative In this case gate  current  flows  through P 2 N 3 junction. Junction N 1 P 2 forward  biased hence the triac  starts  conduction through  P

Find the force-current analog as well as the force voltage, Q. (a) The c...

Q. (a) The concept of duality can be extended to nonelectric physical systems bymeans of analogs. For example, the mechanical system characteristics can be investigated by means

Types of cells and batteries, Types of cells and batteries are:- a.  C...

Types of cells and batteries are:- a.  Carbon-zinc cell b. Nickel-cadmium cell c.  Alkaline celld.  d.  Edison cell e.  Mercury cell

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd