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Empirical models have been reported earlier to estimate the resistivity of electrically exploded conductors (EECs) as a function of geometrical parameters only, such as cross-sectional area and length. Since inductance of inductive energy storage system (IESS) also affects the resistivity of EEC, similar models but with modified empirical coefficients are reported here by including inductance of IESS which makes them applicable for the prediction of resistivity of EEC at different time-scales/systems. Using curve fitting on experimental data reported earlier, methods to evaluate modified empirical coefficients are presented. Circuit simulations carried out using these models are able to predict the current as well as voltage profile in EEC and load for different inductances of IESS. Experiments have been carried out to validate the results predicted by simulation and are found to be in close agreement. [ABSTRACT FROM AUTHOR]

This paper is aimed at finding the effect of varying inductive energy storage systems’ (IESSs) inductance on resistance of an electrically exploded conductor-based opening switch and profile of current transferred into load, which has not yet been fully understood. Based on experimental results obtained, it is observed that when the inductance of IESS is varied, the magnitude of load current changes so as to conform to the magnetic flux conservation law but its rise time remains unchanged. Resistance of the opening switch and energy deposited in it has been estimated using recorded voltage and current waveforms. It has been found that with increasing inductance of IESS, the resistance of switch increases, whereas energy deposited in it decreases. Using these estimated values of energy, a possible explanation of observed behavior in resistance is presented. Effect of a mismatch between the inductance of IESS and load is seen to only affect the energy transfer efficiency or magnitude of load current but not its rise time emphasizing the novel finding that for a given load, the rise time of load current is independent of the inductance of IESS. [ABSTRACT FROM AUTHOR]

This paper describes a low-cost ignitron-based switching scheme for transferring energy from capacitor bank to various loads, used in plasma physics and other pulsed power applications. Battery-operated driver modules have been designed to simultaneously trigger two ignitrons in parallel by using either transistor-transistor logic pulses or optical pulses using a fiber-optic interface with optical fibers of length up to 50 m, for applications prone to generate electromagnetic interferences. These driver modules are designed using insulated gate bipolar transistors as switches to deliver a pulse of amplitude of ~500 A and rise time of ~1.2 μs to the ignitor-cathode junction of their respective ignitrons. The modules are designed to facilitate triggering of multiple ignitrons required for large current applications. The feasibility of this scheme and the performance of designed circuit are characterized using a test setup. Statistical variation of triggering delay for single ignitrons is studied extensively, and the effect of trigger energy on statistical parameters is reported. Jitters of 63.5 and 85 ns, respectively, have been observed for triggering of each ignitron used in this scheme. Difference in triggering of two ignitrons connected in parallel is also studied, and a jitter of 150 ns is observed in the onset of current discharges through individual ignitrons. [ABSTRACT FROM PUBLISHER]

Conventional pulsed power devices such as Marx generators, Tesla transformers, and cable-based generators are usually bulky and occupy a large volume when used for generating high-voltage pulses of duration longer than 100 ns. Cable-based generators also have the limitation of generating half the charging voltage when delivering the entire energy into a matched load. Inductive energy storage systems provide an alternate and effective scheme to overcome these issues. However, their efficiency depends upon the performance of opening switches. Also, inductive energy storage systems do not typically generate flat-top voltage pulses that are desirable for driving various pulsed power loads. In this paper, a new device, named the tapered helical pulse-forming line-based pulse transformer (THPFL-PT), is designed to overcome the above-mentioned drawbacks. The device performs two actions at the same time, i.e., it steps up the input charging voltage, and it generates a flat-top nanosecond voltage pulse. It is developed and characterized at low voltages to verify the feasibility of the concept developed and design parameters. The entire device is compact, with length of about 330 mm. It is capable of generating a voltage pulse of magnitude higher than the charging voltage with a duration of about 100 ns and almost a flat-top profile. [ABSTRACT FROM PUBLISHER]