Elimination of noise from current measurements on pulsed discharge devices
S. S. Medley · cIRcle (University of British Columbia) · 2011
A Rogowskl coil has been used to measure current in a pulsed discharge circuit. The frequency response of the coil has been determined experimentally, It has been established that the noise signal associated with the measurement of a pulsed discharge current is due principally to the electromagnetic radiation from the spark gap switches required in such a circuit. The radiation can be reduced by pressurizing the spark gap with argon, but at the same time the breakdown potential of the switch becomes erratic. A simple measuring system has been devised which completely eliminates the noise signal from the current waveform. The system consists of a balanced differential preamplifier which is fed by a completely balanced measuring circuit into which a 0.5µ sec delay line has been incorporated.