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A DC supply of 100 V feeds an inductance of 10 H through a thyristor. What is the minimum width of the gate pulse so that the thyristor is triggered, if the latching current of thyristor is 80 mA ? 

A DC supply of 100 V feeds an inductance of 10 H through a thyristor. What is the minimum width of the gate pulse so that the thyristor is triggered, if the latching current of thyristor is 80 mA ?  Correct Answer More than 8 ms

At t = 0, we give gate signal to thyristor, then for t≥ 0,

VL = VS

VS =  L .(di/dt)

di = (VS/L) dt

IL = (Vs/L) tmin

tmin = (IL × L)/ Vs

= (10 × 80 × 10-3) / 100 = 8 ms

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