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

Cpi compare immediate instruction , CPI Compare Immediate Instruction ...

CPI Compare Immediate Instruction The 8 bit  data  specified  in the  instruction is  compared with the  contents of the accumulator. The comparison  is done by  subtracting

Chemical vapour deposition, Explain chemical vapour deposition method for t...

Explain chemical vapour deposition method for the preparation of nanomaterial and its properties

P type material - semiconductor material, p type material: p type ma...

p type material: p type material is formed by doping aerial  crystal with impurity atoms having three valance electrons. The diffused impurities with three valence electrons

Push psw instruction , PUSH PSW Instruction It is similar to above  pu...

PUSH PSW Instruction It is similar to above  push  instruction but instead of normal  register Paris it use PSW as its  operand. Program status  word comprises of  the content

What do you mean by heat sink?, Q. What is a heat sink? List the factors, w...

Q. What is a heat sink? List the factors, which determine its efficiency. To reduce the chance of thermal runaway, the rise of temperature at the collector junction to a danger

Opto couplers, Is there an opto-coupler that has a blocking voltage, VRRM, ...

Is there an opto-coupler that has a blocking voltage, VRRM, of greater than 800 volts? Perhaps, 1200 or 1600 volts? The manufacturer?

Voltages source inverter - vsi, Voltages source inverter ( VSI) A volta...

Voltages source inverter ( VSI) A voltage  source  inverter is a constant voltage  source  which  is having  negligible  impedance. In these inverters the amplitude of output

Explain solid-state control of dc motors, Q. Explain Solid-State Control of...

Q. Explain Solid-State Control of DC Motors? Dc motors, which are easily controllable, have historically dominated the adjustable-speed drive field. The torque-speed characteri

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