For some hands on learning cheap, Jameco http://www.jameco.com has a PWM kit catalog K8004 for $19.95. Documentation is minimal but you can download the datasheet for the driver chip from the Web. It'll switch 6.5 amps at 35 volts and can drive an auto ignition coil to provide a hv output. Not Thor- or Hivolt-class but the idea is similar.
Steve
Created on Friday, March 2, 2001 9:16 PM EDT by Steve Hansen