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

Determine supply current and reactive power, A single phase line has an imp...

A single phase line has an impedance of 8.4 + j11.2 Ω. The line feeds a load consisting of a resistor and an inductor connected in parallel as shown in Figure 1. The load is absorb

Rms values, 1. Derive the necessary formula/method to determine the effect...

1. Derive the necessary formula/method to determine the effective value or RMS of a triangular wave. Use either a similar method to the class example of the RMS determination

Linear and IC applications, bias compensation techniques for ac and dc char...

bias compensation techniques for ac and dc characteristics

Define the tick of the property, Tick of the property, which is different f...

Tick of the property, which is different from the group (A) Ductility.                (B) Resistivity. (C) Tensile strength.   (D) Hardness. Ans: Tick of the pr

Explain register direct and indirect data addressing mode, Explain Register...

Explain Register Direct and Indirect data addressing mode (with examples) available in microprocessors. Register Direct Modes and Register Indirect Modes: Does not giv

Calculate the power transferred across the air gap, A three-phase, 5-hp, 22...

A three-phase, 5-hp, 220-V, six-pole, 60-Hz in- duction motor runs at a slip of 0.025 at full load. Rotational and stray-load losses at full load are 5% of the output power. Calcul

Explain types of addressing modes, Problem: a) Explain types of "Addres...

Problem: a) Explain types of "Addressing Modes". b) What is the difference between "Rotate" and "Swap" Operations? c) A computer spends a lot of time in moving data from

Biasing clamper, Ask question #Minwhat is biasing of clamper imum 100 words...

Ask question #Minwhat is biasing of clamper imum 100 words accepted#

Value of current if resistance connected to the battery, One battery having...

One battery having of eight cells in parallel. Emf and internal resistance of every cells is 1.5V and 0.4Ω. Find the value of current if an external resistance of 5Ω is connected t

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