*** Note: See Energy Weapons for more HV switching/modulator ideas

*** Note: See Miscellaneous for warning about dangerous bremsstrahlung radiation from high power switching!

 


ALAMEDA APPLIED SCIENCES CORP.
1555 Doolittle Dr., Suite 100
San Leandro, CA 94577
Phone:
PI:
Topic#:
(510) 483-4156
Rahul R. Prasad
BMDO 96-014
Title: Diamond Solid State Switch for Pulsed Power and Other Applications
Abstract: Alameda Applied Sciences Corporation (AASC) proposes a two phase effort with the ultimate goal of producing a marketable high power, high repetition rate diamond switch suitable for use in several defense and commercial applications. In Phase I a set of experiments will be carried out that will show operation at kilohertz frequencies with closing and opening times <10 ns. While operation at these frequencies has been suggested in the past no experiments showing sustained operation have been reported. In Phase II, the knowledge gained in the Phase I research would be applied to the manufacture and demonstration of prototype diamond switches designed to switch both high current and high voltage at high frequencies. AASC is confident that a 24 month Phase II effort is adequate to establish a product line of devices for several diverse applications that will garner market share immediately following the proposed SBIR funded effort. The potential payoff for diamond switches in defense and commercial applications may be enormous. The properties of diamond suggest the ability to control hundreds of megawatts with a single device. High voltage, high repetition rate switches capable of holding off several hundred kilovolts in a small package are potentially feasible.

PXL, INC.
1-H Deer Park Drive
Monmouth Junction, NJ 08852
Phone:
PI:
Topic#:
(908) 329-0505
Edward J. Miller
BMDO 96-005
Title: High Temperature, High Power Fast Plasma Switch
Abstract: We will demonstrate ultrafast, high power switching technology capable of operating within high temperature environments {> 300 C). The technology is based on generation of Continuous Extension Laser Spark (CELS) by Besselian laser beam. These switches are capable of ultrafast switching GW peak power electrical pulses within high temperature environments, operate with subnanosecond delay, rise time, jitter, and electrical pulse shape programmability. The switch developed in Phase I will operate with 30 MW peak powers, 0 - 30 kV voltage range, 5 kA current capacity, < 5 ns rise time, and subnanosecond delay and jitter within temperature ranges of 300 - 500 C. The effects of high temperature operation on the maximum switching voltage, rise time, jitter, laser trigger energy, and switch lifetime will be studied. Phase II will further advance the technology to achieve the following operating parameters: 0 - 200 kV voltage capacity, 5 kA current capacity, subnanosecond rise time, subnanosecond delay and jitter, and > 20 Hz repetition rates, with 1 ns 10 mJ laser. With technological advancements in high repetition rate laser systems, a 1 GW, 1 kHz plasma switch operating within > 300 C environments can be realized using the proposed technology.

ALAMEDA APPLIED SCIENCES CORP.
6250 Bullard Drive
Oakland, CA 94611
Phone:
PI:
Topic#:
(510) 483-4156
Rahul Prasad
DARPA 95-008
Title: High Voltage, High Power Diamond Solid-State Switch for Pulsed Power and Other Applications
Abstract: Alameda Applied Sciences Corporation (AASC) proposes a three phase effort with the ultimate goal of producing a marketable diamond switch suitable for several pulsed power and other applications in the defence arena. The presently used spark gaps have several drawbacks including switch jitter, large and variable inductance, lifetime and physical size. A low inductance solid-state switch capable of switching 100 kV, 100kA at a high repetition rate would be desireable. The physical and electrical properties of diamond make it uniquely suited to very high power electrical switching applications. Electron beam controlled diamond switches have been demonstrated at moderate (22 kV) voltages and current densities >5 kA/cm2. Diamond, normally a good insulator, can carry large currents when electron-hole pairs are created by the absorption of an energetic electron beam. The objectives of the Phase I research is to study the switching properties of diamond under high field stress (1-10 MV/cm) to develop a design for a practical diamond switch. The switch will be fabricated and validated in Phase II. Commercialization is planned for Phase III. Anticipated Benefits: DoD's pulsed power supplies for nuclear weapons effects simulators and other applications including high power lasers would benefit from the low inductance, low jitter, fast rise-time, high power diamond switch to be developed under the proposed effort. Potential applications include switching systems for the nation's power grid, high power accelerators, the More Electric Aircraft, automobiles and drilling rigs.

PRO-TECH
47 Lafayette Circle #364
Lafayette, CA 94549
Phone:
PI:
Topic#:
(510) 254-6651
Dr. David V. Giri
AF 98-099
Title: High-Power Triggered Gas Switches
Abstract: Examples of UWB sources that have used self-closing spark-gap type of gas switches are: 1)H-series systems at AFRL, 2)Sniper and EMBL at Sandia, and 3)Prototype IRA pulser built by Pro-Tech and PSI. There are several reasons for developing triggered versions of the basic high-voltage spark-gap. They include synchronization with an external event, timed-array antenna application for steering directed energy systms etc. We are proposing to design a short-pulse testbed facility in Phase I. The system will be fabricated and delivered in Phase II. This facility will be modular and flexible to permit studying different typer of electrical and laser triggers, gas mixes, electrode geometries etc. In Phase I, we will also design an appropriate dunny load and a candidate antenna array. Initially, a linear timed-array antenna will be considered and evaluated in Phase I. The dummy load and linear array will be fabricated in Phase II.

ALAMEDA APPLIED SCIENCES CORPORATION
2235 Polvorosa Avenue, Suite 230
San Leandro, CA 94577

Phone:
PI:
Topic#:
(510) 483-4156
Dr. Rahul R. Prasad
BMDO 98-014
Title: Optically Controlled, High Repetition Rate, High Power Diamond Switches
Abstract: Alameda Applied Sciences Corporation (AASC) proposes to develop a new type of trigger for a high voltage, high repetition rate diamond switch. AASC has previously developed diamond switches with electron beam triggers. These switches handle 10-20 kV voltage pulses with <50 ns rise/fall times and switch 10-100 A at temperatures up to 375 C with on-state properties comparable to Si and SiC devices. The electron beam triggered switches require 100-300 keV electron sources to trigger switches handling 5-25 kV. If it is possible to replace the high voltage electron beam trigger with a W trigger, overall system architecture would be greatly simplified. In Phase I a set of experiments will be carried out that will show operation at ~100 MHz frequencies with closing and opening times <10 ns, using W radiation as the trigger. In Phase II, the knowledge gained in the Phase I research would be applied to the manufacture and demonstration of prototype W triggered diamond switches designed to switch both high current and high voltage at high frequencies. AASC will establish a product line of devices for several defense and commercial applications immediately following the proposed SBIR funded effort.

ELECTRODYNAMICS ASSOC., INC.
409 Eastbridge Drive
Oviedo, FL 32765

Phone:
PI:
Topic#:
(407) 977-1825
Jay Vaidya
AF 99-206
Title: High Voltage 100-500 kW Power System for Directed Energy Weapons
Abstract: High voltage power sources will be required for Directed Energy Weapons (DEW) on future fighter planes, staellites, and space planes. Our proposal focuses on the 100-500 kW power range at 100's kV dc voltage level. Generator technology capable of producing high levels of ac voltage, step-up transformer, and power conditioning unit are covered. The disign goals are: high power density, releability, cycle efficiency, and quality of electric power. Permanent Magnet (PM) synchronous and induction generator technologies as well as improved winding insulation and cooling schemes will be evaluated. The Integrated Poer Unit (IPU), which is currently under development at WPAFB is considered the baseline. This allows use of existing mechanical hardware from the IPU for the development testing during Phase II. A number of options for the controller topologies for the 2 generator types are discussed. The optimim topology will be down-selected after complete evaluation. Electric Start function will be included. Final report comprising the generator and controller design will be submitted at the end of the first 6 monlth period. Following 3 months Phase I Option period will be utilized for generator design layout, system simulation and cost estimates. The entire activity will be executed by an inter-disciplinary team of experts assempled by Electrodynamics.

ALAMEDA APPLIED SCIENCES CORP.
1555 Doolittle Drive, Suite 100
San Leandro, CA 94577

Phone:
PI:
Topic#:
(510) 483-4156
Rahul R. Prasad
BMDO 99-001
Title: Diamond switch for RF pulse compression
Abstract: Alameda Applied Sciences Corporation (AASC) proposes to develop a new type of RF and millimeter wave amplifier based on pulse compression. The amplifier is based on the use of a diamond membrane that is turned from an insulating state (thus transmitting RF) to a conducting state (thus reflecting RF) when irradiated by ultraviolet (UV) radiation. Such a RF amplifier is an enabling technology for a whole class of high power RF and millimeter wave devices that would otherwise be impractical. The Phase I to demonstrate the feasibility of the concept. A chemical vapor deposition diamond window will be irradiated with UV radiation from a laser (4th harmonic Nd:YAG) and reflection of microwave power from the window will be demonstrated. The UV power required for practical devices will be determined. The Phase II effort will develop a RF amplifier using the pulse compression technique. The diamond switch will be coupled to a high power microwave source such as the phigtron, developed at the University of Maryland. The Phase III will be an aggressive commercialization campaign aimed at the several military and civilian uses of high power RF.