LTSpice models of a switch commutated SCR (shorting the SCR directly), switch commutated SCR through a series L-C to the SCR's anode, and SCR commutated through a series L-C to the main SCR's anode.

This models represents implementations of Figs 1-9A, 1-11, and 1-12 from <http://groups.yahoo.com/group/Electronics_101/files/Nuno%20Tavares%20files./Turning%20off%20an%20SCR.pdf>

 All values are nominal and approximate, but it demonstrates the current flow through the switch at commutation. Uses SCR models from the LTspice Yahoo! group.  I'll look up the actual source and post it here.