i am swathi, b.tech 4th year.
In smps(switched mode power supply)we are using
diodes,mosfets,igbts for controling of current.
And my question is why we did not use thyristors(scr)? it
is also act as a switch,then what is the drawback of scr as
compared to above transisters> if we use the scr,then what
is happening ? plz give reply as soon as possible bcoz i
am doing project on smps. plz frnds i want ans for
that. if anybody know the ans plz send to my e-mail
Answers were Sorted based on User's Feedback
Answer / nithi
SCR cannot be used due to the following reason.
1.we have to design commutation circuit for SCR.(this will
increase the complexity of the circuit)
2.cost of SCR is higher than MOSFET,TRANSISTOR & IGBT.
3.SCR is current controlled device .This will increase the
load on the triggering circuit.
4.The voltage drop & power loss in SCR is somewhat higher
than mosfet,igbt & transistor.
5.moreover,the switching frequency of the SCR is very low
so,I think it is better to use MOSFET,IGBT & TRANSISTOR as
a switching device in SMPS.OK............
|Is This Answer Correct ?||19 Yes||3 No|
Hi dear this is prasad from clp (power)...we can use
thyristor(scr) but for scr we have to design firing angle
circuit separatly,we have to check whether scr is
triggering or turning on exatctly as per our requirements
or not and for high power applications it is better to
diodes,mosfet,igbts..in these we wont face firing angle
circuit design problems...bocz for the SCR firing circuit
is the heart hope so....
|Is This Answer Correct ?||10 Yes||6 No|
Answer / g venkateswarlu
hi dear swathi,as per your question SCR act as switch but it is current controlled device and its operating frequecy is 400-500hz, voltage drop less than 2 volts,and its application are dc motor control and rectifier and inverter. where as MOSFET AND IGBT voltage control device and above nithi ans also correct
|Is This Answer Correct ?||0 Yes||0 No|
Answer / anjun
hi swathi....its better to ask in GATE FORUM, where u will find correct ans......Anjun
|Is This Answer Correct ?||0 Yes||2 No|
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