Answer / nilkanth tailor

THYRISTORS: SCR,GTO.TRIAC..etc...
POWER SWITCH: IGBT,MOSFET...

thyristorts is like diode mainly unipolar device, only
conducts in one direction.
By the way TRIAC(AC switch- made by cross parallel
connection of SCR) can conduct in both direction but it
reactive loads can cause it to fail to turn off during the
zero-voltage instants of the ac power cycle...so require
snubber circuit to turn off that TRIAC in each half cycle...
so it has to take more time to turn off or on...in
comparison of IGBT and MOSFET...

At high freq switching devices thyristors can not use
becouse at high freq , time is inversely proportinal to the
freq, so thier is less time require to operate. AT that
time we require IGBT- fast switching response

Answer / venky

thyristor is a thyristor

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