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

Parts of triangle, The base of isosceles triangle and the altitude drawn fr...

The base of isosceles triangle and the altitude drawn from one of the congruent sides are equal to 18 cm and 15 cm, respectively. Find the lengths of the sides of the triangle.

Define the universal property of nand and nor gates, Define The universal p...

Define The universal property of NAND and NOR Gates? The NAND and NOR gates are called universal gates, because any gate can build by using these two gates. The univers

Define memory for a digital computer, Q. Define Memory For a digital comput...

Q. Define Memory For a digital computer? For a digital computer which stores both programs and data, memory can be divided into three types: random-access memory, mass storage,

Mould casting, Mould Casting: Plaster Moulding : In this method, the...

Mould Casting: Plaster Moulding : In this method, the mould is prepared in gypsum or plaster of paris. In practice, the plaster of paris is mixed with tale, asbestos, fibers

Compute the kvar and the power factor of the motor, Q. A three-phase balanc...

Q. A three-phase balanced load draws 100 kW at 0.8 power factor lagging. In order to improve the supply power factor to 0.95 leading, a synchronous motor drawing 50 kWis connected

Amplifiers, what is the use of capacitors in amplifiers

what is the use of capacitors in amplifiers

Explain working of ring topology, Q. Explain working of Ring Topology? ...

Q. Explain working of Ring Topology? Ring Topology: In ring topology, all user nodes are connected with physical path acting as links of a chain and last user node is co

For carry flag - return instructions , For Carry Flag  RC (Return of ...

For Carry Flag  RC (Return of Carry) and RNC ( Return on no Carry) Instruction RC returns from  the subroutine  to the calling  program if carry  flag is et (CY= 1). The

Canonical sum-of-products form, Q. The truth table for F(A,B,C) = mi (2, 3,...

Q. The truth table for F(A,B,C) = mi (2, 3, 4 5) is as follows: (a) Express F in a canonical sum-of-products form. (b) Minimize F in an SOP form, and obtain a possible realiz

Explain working of bipolar junction transistors, Q. Explain working of Bipo...

Q. Explain working of Bipolar junction transistors? The family of bipolar junction transistors has two members: the npn BJT and the pnp BJT. Both types contain semiconductor ju

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