DAHLGREN, Va.-- A new development in electromagnetic technology patented in May of this year will impact future military capabilities, Navy officials announced Aug. 13.
The superconducting stator patent describes a discovery that enables a magnetic flux compression generator to produce an electromagnetic pulse (EMP).
"Most conventional magnetic flux compression generators are explosively driven, dangerous to handle, and limited to one-time use," said Albert Corda, a Naval Surface Warfare Center Dahlgren Division (NSWCDD) physicist. "The novel architecture of the generator described in this patent, however, is not explosive in nature. It's inherently safer to handle and potentially reusable."
An EMP is characterized as a broad band signal with a frequency-power distribution ranging from a few hundred kilohertz to a few gigahertz. The magnetic flux compression generator is designed to generate a high voltage pulse output that can be incorporated into an EMP generator.
The patent - jointly filed by scientists from NSWCDD in Virginia and NSWC Carderock Division in Maryland - began as they collaborated at the Chief of Naval Operations Strategic Studies Group in 2008.
"The idea originated from a side-bar discussion that centered on the utility of high temperature superconducting materials," said Dr. Jack Price, NSWC Carderock scientist. "These materials - composed of particular copper oxides called cuprates and typically layered on top of a nickel substrate - have very low resistance at liquid nitrogen temperatures. Someone posed a 'what if' question. We earnestly discussed all the possibilities and technical difficulties and the concept was born."
The concept resulted in a device designed to produce a short duration, highly localized electromagnetic pulse controlled by a superconducting stator that also enables multiple activations of the flux compression generator.
"The architecture provides elements of scalability and control not possible with conventional magnetic flux compression generator designs," said Corda.
Conventional magnetic flux compression generators have been in existence since the 1950s with initial work for the United States being carried out at Los Alamos, N.M. Now, much smaller generators featuring high power pulses with very fast rise times can be made.
"The proposed superconducting stator is potentially practical and affordable given the commercial availability of high temperature superconductor materials that operate at liquid-nitrogen temperature," said Price.
Military and industrial applications depend on the output configuration but can range from the production of broadband radio frequency transmissions to the rapid acceleration of physical mechanisms to high velocities.
"Each of the warfare center divisions has particular mission areas of expertise," said Blaise Corbett, of the NSWCDD EMP Assessment Group. "Dahlgren has a long history and expertise in pulsed power systems and applications. Carderock has expertise in high temperature superconducting (HTS) materials and applications evidenced by their development of a HTS degaussing system and motor."
The patent's inventors included Price and Dr. Y. Dan Agassi from NSWC Carderock Division in addition to Corda, Corbett, and Dr. Walter Sessions from NSWC Dahlgren Division.
"Our leadership encourages collaboration between the warfare center divisions when synergies exist that can be effectively leveraged to benefit the Navy," said Corbett. "This is only one of a number of collaborations between scientists at Dahlgren and Carderock. Ongoing collaborative efforts can be expected to yield other novel and innovative concepts focused on the Navy's needs in the months and years ahead."