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

Need of microphone in telephone hand set, Q. Need of Microphone in telephon...

Q. Need of Microphone in telephone hand set? Microphone: For all practical purposes, microphone is transmitter for telephone. The microphone converts acoustical signals in the

Floor number display, It is required that the current floor position be dis...

It is required that the current floor position be displayed as a number 1, 2, or 3 on a seven segment LED display on floor 1, which is quite close to the LCU. Data Storage It

Uses of fet, Uses of FET IGBTs (Insulated-gate bipolar transistor) se...

Uses of FET IGBTs (Insulated-gate bipolar transistor) see application in switching internal combustion engine ignition coils, in which fast switching and voltage blocking cap

Find the number of possible station frequencies, Q. Find the number of poss...

Q. Find the number of possible station frequencies in the AM broadcast system in the United States

Determine the magnetic force on the current element, Q. Given ¯B = (y ¯ax -...

Q. Given ¯B = (y ¯ax - x ¯ay )/(x 2 + y 2 ) T, determine the magnetic force on the current element Id ¯l = 5 × 0.001¯a A located at (3,4,2).

Explain symmetrical t-attenuator, Question 1 State and Explain Kirchhoff's...

Question 1 State and Explain Kirchhoff's Voltage and Current Law Question 2 State and prove Thevenine's Theorem Question 3 What is a filter? Design a Constant -K band Pa

Sui subtract immediate i instructions , SUI  Subtract Immediate I Instruct...

SUI  Subtract Immediate I Instructions The 8 bit  data  specified  in the  instruction  is directly  subtracted  from the  contents of  accumulator  and results  of operation

Calculate the current flow using norton theorem, Calculate the current flo...

Calculate the current flow in 30Ω resistor for the circuit in figure using Norton Theorem.

What do you mean by sub address, Q. What do you mean by sub address? A ...

Q. What do you mean by sub address? A sub address, though a part of the ISDN address, isn't considered as an integral part of the numbering scheme. Sub address is carried in a

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