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

Why positive feedback is used in oscillator, Q. Why positive feedback is us...

Q. Why positive feedback is used in oscillator? The main application of positive feedback is in oscillators. An oscillator generates AC output signal without any input AC signa

Find the thevenin equivalent, Task 1 Use basic circuit theory to...

Task 1 Use basic circuit theory to convert the "T" circuit below into the equivalent "π". Hint: Remember to disconnect the voltage source and the load. Task 2

Moving coil transducers, Note transducers  convert a physical quantity from...

Note transducers  convert a physical quantity from one  form to another.  The case below illustrates a typical moving coil meter   that   converts   a   current into a mechanical a

Create a time diagram - conveyer, When the PLC is in the RUN mode it will s...

When the PLC is in the RUN mode it will switch ON the conveyer so it will run continuously. This project is divided into four outcomes: (a)    Detect block on entry, close

Draw a relay construction diagram, Draw a relay construction diagram and br...

Draw a relay construction diagram and briefly explain the operation of a relay. Define the terms normally open and normally closed. Define the terms Set and Reset for relays.

Engineer, Transmission Through a LiNb0 3 Plate Examine the transmission of...

Transmission Through a LiNb0 3 Plate Examine the transmission of an unpolarized He-Ne laser beam (?o= 633 nm) normally incident on a LiNb0 3 plate (ne = 2.29, no = 2.20) of thickn

Petri nets, Discrete Systems Control: cat and mouse example with 4 rooms us...

Discrete Systems Control: cat and mouse example with 4 rooms using petri nets

Introduction to power systems, Q. Introduction to power systems? Thomas...

Q. Introduction to power systems? Thomas A. Edison's work in 1878 on the electric light led to the concept of a centrally located power station with distributed electric power

Discuss in brief on combination clippers, Q. Discuss in brief on combinatio...

Q. Discuss in brief on combination clippers ? Combination clippers are a combination of biased positive and negative clippers. With a combination clipper, a portion of both pos

Nicol prism, how much and what to write it is of 30 marks

how much and what to write it is of 30 marks

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