Accession Number : ADA293871

Title :   Electrical Performance Characterisation of Single-Shot Switches in High Speed, High Voltage and High Current Applications.

Corporate Author : DEFENCE SCIENCE AND TECHNOLOGY ORGANIZATION CANBERRA (AUSTRALIA)

Personal Author(s) : Podlesak, Michael

PDF Url : ADA293871

Report Date : AUG 1994

Pagination or Media Count : 49

Abstract : The electrical performance characteristics of single-shot closing switches for slapper detonator applications were measured via the discharge of a low impedance transmission line. The switch performance, characterised by its time-dependent resistance behaviour, could not be assessed via the more conventional methods of measurement because of high bandwidth requirements at comparatively high levels of voltage and current. Hence, an alternative technique based on a transmission line discharge was devised in which the time-dependent resistance of the switch can be determined from the measured current waveform of the switch, the initial open circuit voltage and the transmission line parameters only. Under certain conditions a simple lossless transmission line formula is sufficient for the calculation of the switch resistance waveform. However, if the transmission line losses cannot be neglected, a correction can be readily implemented through numerical signal processing. The bandwidth of this technique is limited to the bandwidth of the switch current measurement only, which proved to be particularly useful for the measurement of switches for slapper detonator applications where inductive pick-up noise in the switch voltage waveform is large and where high voltage probes of sufficiently high bandwidth are not readily available. In this report, both numerically simulated and experimental examples are given, together with the method of calculation of switch resistance which takes into account practical transmission line losses. It was found that best results are obtained if the magnitude of the switch resistance is of a similar order as the characteristic impedance of the transmission line, or higher.

Descriptors :   *PERFORMANCE TESTS, *ELECTRICAL PROPERTIES, *ELECTRIC SWITCHES, SIGNAL PROCESSING, HIGH POWER, REQUIREMENTS, MEASUREMENT, PROBES, TIME DEPENDENCE, PARAMETERS, HIGH VELOCITY, RESISTANCE, WAVEFORMS, NUMERICAL ANALYSIS, VOLTAGE, TRANSMISSION LINES, BEHAVIOR, CIRCUITS, BANDWIDTH, IMPEDANCE, TRANSMISSION LOSS, HIGH VOLTAGE, DETONATORS.

Subject Categories : Electrical and Electronic Equipment

Distribution Statement : APPROVED FOR PUBLIC RELEASE