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

Consumer interaction and service standards, Consumer Interaction and Servic...

Consumer Interaction and Service Standards These KPIs deal along with the customer, internal business procedures and change management. These are significant to give the desir

Describe the process control instructions, Describe the process control ins...

Describe the process control instructions STC - It sets the carry flag & does not affect any other flag  CLC - it resets the carry flag to zero &does not affect any other fl

Transformer cooling, An oil-filled transformer has a c.m.r. of 500 kVA whic...

An oil-filled transformer has a c.m.r. of 500 kVA which allows it to run continuously in an ambient of 35°C with an oil temperature rise of 50°C. The transformer has a time constan

Solar energy, project for solar panel for farms in Saudi Arabia

project for solar panel for farms in Saudi Arabia

Find the truth table and the type of gate, Q. The DeMorgan's theorems sugge...

Q. The DeMorgan's theorems suggest that the basic logic operations can be realized by use of inverters and NAND gates only. For the circuits shown in Figure,  find the truth table,

Find the value of frequency, Although the low side is not as good a choice ...

Although the low side is not as good a choice as the high-side local oscillator frequency, let an AM broadcast receiver be designed with a low-side local oscillator. As fc is varie

Explain the effect of feedback on amplifier bandwidth, Q. Explain the effec...

Q. Explain the effect of feedback on amplifier bandwidth? The bandwidth of an amplifier is defined as the range of frequencies for which the gain remains constant.The gain -ban

Show block diagram of a 4-bit parallel-input shift register, Q. Show a bloc...

Q. Show a block diagram of a 4-bit, parallel-input shift-right register and brie?y explain its operation.

Kirchoff''s current law, Kirchoff's Current Law The total current ent...

Kirchoff's Current Law The total current entering a node in a circuit is equal to the total current leaving that node. A Node is a junction between two or more components.

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