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

Digital signal processing, A DT LTI system has the following impulse respon...

A DT LTI system has the following impulse response: h(n)=[cos(pi/+delta(n)] u(n-3)u(n-2) (a) Find the system’s frequency response h(e^jw ). (b) Sketch the magnitude and phase respo

For carry flag - conditional jumps , For carry Flag JC (  jump on  Ca...

For carry Flag JC (  jump on  Carry ) and JNC (Jump  on No carry ) Instructions : JC transfer the  execution of the  program to the  specified memory  address if  carry

For the circuit obtain z- and y-parameters, Q. For the circuit shown in Fig...

Q. For the circuit shown in Figure, obtain: (a) z-and y-parameters; (b) Transfer function I 2 /I 1 when V 2 = 0.

Explain about the term embedded system, Explain about the term embedded sys...

Explain about the term embedded system. An embedded system is a system which has software embedded within computer-hardware that makes a system dedicated for an application(s)

Find the per-unit voltage regulation, Q. A single-phase, 3-kVA, 220:110-V, ...

Q. A single-phase, 3-kVA, 220:110-V, 60-Hz transformer has a high-voltage winding resistance of 0.3 , a low-voltage winding resistance of 0.06 , a leakage reactance of 0.8  on i

Determine the transfer function and driving-point impedance, Q. A filter is...

Q. A filter is a network employed to select one range of frequencies while rejecting all other frequencies. A basic building block often used in integrated-circuit filters is shown

Illustrate how to replace the ht fuse, Illustrate how to replace the HT Fus...

Illustrate how to replace the HT Fuse on a 6-pole and 4-pole structure? Ans: a) Open switch on 6-pole or 4-pole. b) Connect the discharge rod between earth and conduc

Differentiate thermoplastic & thermosetting plastic material, Classify plas...

Classify plastic materials into two categories describe their important properties and give two examples of each. Plastic materials can be categorized in thermoplastic and ther

Analysis of aspects of design for excellence, We commissioned a 'bad practi...

We commissioned a 'bad practice exemplar' by asking Plexus to modify a good design (provided by Valor) to demonstrate the most likely kinds of faults in each of the areas Design fo

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