Basically a high voltage generator. A 24VDC input is converted into 150.8Vpp sinewave by a ZVS self-oscillator, amplified 100 times in a transfomer, then boosted to 60kV-ish by a 8-stages C-W Rectifier. I use an old Canon X-ray tube for dental exams. The whole thing consumes 70~80W with a efficiency of something like 1%.
I spent weeks on the modification of the classic ZVS circuit, but eventually swung to the old fashioned topology, only with CMOS Gate Drive added. Luckily enough calculation has been done so the project provides a analyse of how ZVS actually works.