Picosecond high-voltage pulse measurements.

Abstract

This paper presents capacitive sensors based on oxide dielectric substrates that provide a high attenuation factor of up to 30 · 103 with a transient time of ∼38 ps. The sensors made it possible to significantly reduce the number of attenuators and increase the bandwidth of the measuring path. The presented sensors have been used successfully for recording high voltage to MV pulses in the time range from a few nanoseconds to tens of picoseconds. The use of the sensors as the point receiving antennas for recording radio pulses in the GHz frequency range with high electric fields is also discussed, along with the trough directional coupler as a unit for additional attenuation of the voltage of the sensor response. The couplers have a high attenuation factor of 1-5 · 103 with a transient time of ∼38 ps. Using the couplers as attenuators for recording waveforms further improves the parameters (bandwidth, transient time) of the measuring circuit. A discussion of some features of the operational mode of this type of sensor and coupler with a focus on wave processes is also presented. This discussion can be used to analyze the general approaches to the improvement of the sensor and coupler as components of the measuring circuit. In this paper, the authors also propose methods for calibrating and calculating the attenuation factor of the sensors.