D. c. Charged particle accelerator, a method of accelerating charged particles using d. c. voltages and a high voltage power supply apparatus for use therewith

A d.c. charged particle accelerator comprising:

• accelerator electrodes including end electrodes and at least N-1 intermediate electrodes, said accelerator electrodes defining at least N acceleration gaps between adjacent pairs of said electrodes, where N is at least three;
• and
• regulated d.c. high voltage power supply apparatus having N pairs of output lines connected to respective adjacent pairs of said accelerator electrodes defining said N acceleration gaps, said regulated d.c. high voltage power supply apparatus operative to provide N regulated high voltage d.c. output voltages on said N pairs of output lines to provide gap voltages across said N acceleration gaps, said N regulated high voltage d.c. output voltages being electrically isolated from each other;
• wherein said regulated d.c. high voltage power supply apparatus comprises:
• N d.c. voltage generators being d.c. isolated from each other, each of said voltage generators having a respective one of said N pairs of output lines and being arranged to generate a respective one of said N regulated high voltage d.c. output voltages from input electric power delivered to said voltage generator;
• and
• d.c. isolating power delivery apparatus arranged to deliver said input electric power to said N voltage generators while maintaining d.c. isolation between said voltage generators;
• wherein said N d.c. voltage generators comprise N d.c. high voltage power supply units providing said regulated high voltage d.c. outputs from unregulated input electric power;
• wherein said d.c. isolating power delivery apparatus comprises N alternators to deliver a.c. power as said unregulated input electric power to respective said d.c. high voltage power supply units;
• wherein each said alternator comprises a stator having at least one stator winding and a rotor carrying at least one rotor magnet to produce a rotating magnetic field in said stator to induce alternating currents in said stator winding to provide said a.c. power;
• wherein said stators of at least two of said alternators are axially aligned;
• and said d.c. isolating power delivery apparatus comprises at least one common rotor shaft carrying, axially spaced along said shaft, said rotors of said at least two alternators, and a motor connected to rotate said common rotor shaft.