A pulsed power system converts a low-power, long-time input into a high-power, short-time output.
Many pulsed power systems are built for military applications and output high energy pulses, but with the development of faster, solid state switching components the field has expanded to include the development of lower energy nano- and sub-nanosecond systems that are utilized in a variety of applications, including biomedical, combustion, and agricultural applications. As high power solid-state switches (i.e. MOSFET, insulated gate bipolar transistor (IGBT), thyristor, etc.) have matured, design concepts similar to the ones developed in the 1960s, such as the Marx bank and the Blumlein line, have been realized in compact architectures that are laid out on printed circuit boards, which drastically reduced the interconnect parasitics and enabled fast rise-times and shorter pulse widths.
Serious development of pulsed power systems began with the need to develop state-of-the-art radar systems during World War II, and the development of high energy systems continued to expand after the war. In 1964 Physics International Company built the first Marx generator that charged a liquid-dielectric transmission line and was switched by liquid spark gaps. By 1968 the U.S. Naval Research Laboratory (NRL) had implemented one such system capable of delivering 1 MV at 1 MA. These early breakthroughs led to more modern developments such as the three iterations of the High Energy Radiation Megavolt Electron Source (HERMES) and the Z Facility at Sandia National Laboratories.
Today, as exciting new applications of pulsed power are being explored and discovered, Transient Plasma Systems designs and manufactures compact pulsed power systems for research and industry.
References:
- Schamiloglu et al, Proceedings of the IEEE, Vol 92 (7) 1014 (2004).
- Mankowski, J., Kristiansen, M. “A Review of Short Pulse Generator Technology,” IEEE Transactions on Plasma Science, vol.28, no.1, pp.102-108 (2000).
- Smith, I. “The Early History of Western Pulsed Power.” Plasma Science, IEEE Transactions on 34(5): 1585-1609 (2006).
Transient plasma is a non-thermal plasma that exists during the transient, formative phase of an arc. It is produced by using short, high-voltage pulses, which are short enough (typically less than 100 ns) to prevent the arc from occurring.
In a transient plasma discharge, the energy transfer efficiency is high and significant energy goes into creating highly energetic electrons instead of heating of the surrounding gas. When applied to ignition and combustion, it has several advantages over traditional spark ignition used in most combustion applications. It has consistently demonstrated reductions in ignition delay, lean-burn capability, and the ability to ignite higher mass flow rates, resulting in improved efficiency and reduced emissions from a variety of airborne engines and internal combustion engines. Transient plasma ignition is just one of the many applications of pulsed power systems made by TPS.