Active armor protection-conception and design of steerable launcher systems fed by modular pulsed-power supply units

The impulsive acceleration of active protection elements such as armor plates or other terminal ballistics interception devices can be realized by single-stage electromagnetic launcher systems using pancake coils. The technology with controlled multipartite coil assemblies represents a new topic in the field of ballistics with a high growth potential. During 1999 a separate test facility with modular structured energy packs (3×50 kJ) was built at ISL as a basic installation for testing reinforced or armored coils and multiple-coil systems. Each power supply module comprises one energy storage capacitor, a thyristor stack adapted to maximum charging voltage, a corresponding number of crow-bar diodes and a coaxial power line serving as a pulse forming network and current limiting reactor. To provide high flexibility these modules can be triggered independently by fiber optic transmitters with an overall jitter lower than 50 ns. Three packs are designed for a maximum charging voltage of 10.75 kV. First measurements have shown that peak currents up to 120 kA per module and current slew rates of more than 2.5 kA/μs can be generated. The paper describes the test facility and the prototype arrangement of a steerable launcher system with two orthogonally assembled pancake coils fed by two modular pulsed power supply units. The selection of the launch direction is defined by a short delay between the trigger pulses, so that the usual propagation delay time implied by inertia is avoided. First investigations and results concerning steerability and electromechanical efficiency are presented