Spread time - power semiconductor devices , Electrical Engineering

Assignment Help:

Spread Time (ts)

During  spread time anode  voltage  falls from 10% Ia  to the  on state  voltage  drop  and anode  current  rises  from 90% Ia  to final  value  of anode  current i ,e Ia in this period whole  charges injected from   gate spreads over the entire section of  cathode and anode  current  reaches at steady state  condition.

There the total turn on time  ( ton ) can be written  as

Ton = td + Ir + ts

In these  intervals td tr and ts the rise time is high  a s compared to other. If  rise time it  is reduced beyond  a limit thyrisotr may get destroyed because rate of  rise  of anode  current  may be  large  as compared to the spread velocity of charges and this  may forms a  local  hot spot on the cathode surface of SCR. Turn on  time depends on gate  current. It can be  reduced by using  higher  value of gate  currents.

 


Related Discussions:- Spread time - power semiconductor devices

Determine the cross-sectional conducting area, Q MCM is the abbreviation fo...

Q MCM is the abbreviation for 1 kcmil. problem for a de?nition of cmil.) Data for commercial-base aluminum electrical conductors list a 60-Hz resistance of 0.0880 /km at 75°C for

Mechanical structure of depletion type mosfet, Mechanical Structure of Depl...

Mechanical Structure of Depletion Type MOSFET The mechanical structure of this type of device is displayed in figure. In an IC, we would locate two n-type regions side by side

Back to back test of tranformer, what is the advantage and disadvantage of ...

what is the advantage and disadvantage of back to back test of transformer

Determine the disadvantages of expert systems, Determine the Disadvantages ...

Determine the Disadvantages of expert systems -  Lacks common sense in some decision making processes -  Errors in the knowledge base can result in incorrect decisions being

Calculate the guage pressure, Questions: Part (a) A compressor inst...

Questions: Part (a) A compressor installed at a wharf (for loading container ships) is able to provide 6 bar.g pressure into the pressure receiver. The compressor is moved

Mvi move immediate instruction , MVI Move Immediate  Instruction This...

MVI Move Immediate  Instruction This form  of the instruction is used to copy 8bit  data ( specified  in the  instruction )  directly  into the  register or memory  pointed by

Detection and handling of gas leakage, Detection and Handling of Gas Leakag...

Detection and Handling of Gas Leakage : If you are using a toxic gas or have a store for it you must have some devices to indicate the leakage, if any. Though numerous monitoring

Terminal of a battery having 10 cells connected in series, An external resi...

An external resistance of 10 Ω is linked to the terminal of a battery having 10 cells connected in series. Emf for every cells and internal resistance  is 1.5V and 0.2Ω . Find the

Show quantization process, Q. Show Quantization process Let Figure (a) ...

Q. Show Quantization process Let Figure (a) illustrate a message f (t) with values between 0 and 7 V. A sequence of exact samples taken at uniform intervals of time is shown: 1

Explain the construction and working of calomel electrode , 1.  Explain the...

1.  Explain the construction and working of Calomel electrode 2.  Derive an expression for the electrode potential of a glass electrode. 3.  What are ion selective electrodes

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