help in a Circuit used to fire thyristors

Hello members

i want to design a circuit to supply the firing pulse of the thyristors

i want also its theory of operation.

any help will be appreciated

thank you

Ahmed

The thyristor, will it be a SCR or TRIAC?
Are you going to control a DC or AC load?
In the latter case, will it be phase control, zero crossing or static switching?
How large is your thyristor? Volt/Current ratings.
Sensitive gate SCR?, Three or Four quadrant Triac?
Isolated or non-isolated drive?
Cost?

General Electric's SCR manual has something like 40 pages dedicated to thyristor triggering.