What is Kickback?

To: tesla-at-pupman-dot-com
Subject: What is Kickback?
From: "Lau, Gary" <Gary.Lau-at-compaq-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)
Date: Thu, 06 Jan 2000 12:17:01 -0700
Approved: twftesla-at-uswest-dot-net
Delivered-To: fixup-tesla-at-pupman-dot-com-at-fixme

I see frequent references to "kickback", as something that caps and NST's
need to be protected against.  Can somebody provide a concise definition of
just what this is and its underlying mechanism?  Something that can be
modeled with PSpice?  I want to understand if there really is such a thing,
or is this just a reference to a streamer striking the primary circuit?
Could it be due to the gap misfiring?  Streamer strikes aside, the only
thing that I can see going from the secondary to the primary is, after
quench, the primary and secondary inductors act as an untuned transformer,
but I think the potential for primary damage is small due to the low
efficiency of the untuned transformer.

Thanks in advance,
Gary Lau
Waltham, MA USA