A field based, self-excited compulsator power supply for a 9 MJ railgun demonstrator

Fabrication efforts have begun on a field-based compulsator for firing 9 MJ projectiles from a railgun launcher. The machine is designed to store 200 MJ kinetic energy and fire a salvo of nine rounds in three minutes at velocities between 2.5 and 4.0 km/s. Prime power required to meet this firing schedule is 1.865 kW, and will be supplied by a gas turbine engine. It is also possible to fire a burst of two shots in rapid succession, if desired. Operating speed of the machine is 8250 r/min and it has design ratings of 3.2 MA peak current and 20 GW peak power into a 9 MJ railgun load. A two-pole configuration is used for pulse-length considerations, and selectivity passive compensation is used to produced a relatively flat pulse and limit peak projectile acceleration to about 980000 m/s/sup 2/. Other distinguishing features include an air core magnetic circuit, separate rotor armature windings for self-excitation and railgun firing, ambient temperature field coils, and excitation field magnetic energy recovery capability. A detailed description of the machine as designed, and its auxiliary and control systems, is provided. Fabrication and assembly methods are reviewed, and the current status of the project is discussed.< >