LTD Stages Research Articles

Errata and comments on “thermal decomposition of ammonium perchlorate—A TGA–FTIR–MS study: part I” [Thermochim. Acta 610 (2015) 57–68

Some errata were noticed in the calculated pre-exponential factor (A) data represented in the TGA and kinetic analysis section of the paper “Thermal decomposition of ammonium perchlorate—A TGA–FTIR–MS study: part I” [Thermochim. Acta 610 (2015) 57–68]. In the discussion, we analyse what went wrong during the determination of the pre-exponential factor and subsequently identify the correct values. The correct value of pre-exponential factor (A) for the decomposition of 250 to 300 µm size AP particles during the LTD and HTD stages is found to be 5.70 × 109 min−1 and 2.70 × 109 min−1, respectively.

LTD模块气体开关电极材料烧蚀性能实验

LTD模块气体开关电极材料烧蚀性能实验

40 GW Linear Transformer Driver stage for pulse generators of Mega-ampere range

AbstractLinear transformer driver (LTD) technology is actively developed at the Institute of High Current Electronics in Tomsk, Russia. This technology is being examined for use in high current high voltage pulsed accelerators. Recent development of high voltage low inductance capacitors and low inductance switches enabled to achieve ~100 ns rise time of the LTD output pulse. This technique allows one to eliminate intermediate pulse forming sections, used in the present accelerator technology, which would keep the footprint of an LTD accelerator small. LTD based drivers are currently considered for many applications, including future very high current Z-pinch drivers for inertial confinement fusion, medium current drivers with adjustable pulse length for isentropic compression experiments, and finally relatively low current accelerators for radiography and X-pinches. In this article, we present the design and test results for a new LTD stage, that operates at 100 kV charging voltage. Current amplitude up to 850 kA with ~140 ns rise time was obtained on a 0.05 Ω load. Stack of the LTD stages can be easily assembled in series or in parallel, thus providing voltage or current multiplication, respectively. Design of multi-mega-volt and multi-mega-ampere generators becomes straightforward with the LTD technology.

The Design and the First Test Results of a Fast LTD Stage

Linear transformer driver stages are designed to be used as a primary energy storage in high power pulsed generators. In this report, the design and test results of the linear transformer driver stage prototype that delivers ≈ 100 kA fast pulse with 133 ns FWHM into a ≈ 0.87 Ω resistive load are described. This stage consists of 20 (100 kV, 20 nF) storage capacitors that are arranged in 10 identical bricks located evenly around the axis of the stage. Each brick contains two capacitors, a multi-gap switch, and the output connector that transfers the energy to the resistive load. The outer diameter of the stage is ≈ 1.5 m, at a length of ≈ 20 cm. The stage is developed to demonstrate the possibility of the fast linear transformer driver technology to create high power pulsed generators.

Primary energy storages based on linear transformer stages

Primary storages based on a linear transformer scheme were developed long ago. In this scheme, the secondary turn only has to be insulated from the high output voltage. Seven years ago at the High Current Electronics Institute (HCEI) a primary storage based on a linear transformer scheme and called the Linear Transformer Driver (LTD) stage was designed. In LTD stages, the primary turn, the storage capacitors with the switches, the core, and the outer conductor of the secondary turn are integrated into the stage cavity representing one separate building block of the primary storage. The body of the LTD cavity keeps ground potential during the shot allowing us to assemble them in series or in parallel depending on load requirements. Such flexibility of the storage structure and high output power of the LTD stages allows us to replace for some applications the traditional water line technology with LTD-based primary storages that are connected directly to the load (Direct Drive Scheme—DDS). In this article, we present the design of several LTD stages developed at HCEI and give examples of high-power energy storages produced by using the LTD technology.