To ensure successful turn-on of a thyristor, the minimum gate pulse width of the thyristor gate pulse should be sufficient to ensure the cathode current to reach
Right Answer is:
The latching value of thyristor current
When the SCR is triggered, the gate current is not required for SCR to remain in the ON state. If the gate current is removed, the conduction of current from anode to cathode is unaffected. However, if the gate current is reduced to zero before anode current attains a value called latching current, SCR will turn OFF again.
Latching current is defined as the minimum value of anode current, that is to be attained during the turn-on process, to maintain conduction when the gate signal is removed.
SCR can be turned OFF by reducing anode current below a value called holding current. Holding current is defined as the minimum value of anode current below which SCR will cease to conduct.