Modeling high impedance connecting links and cables below 1 Hz

TL;DR

This paper investigates the low-frequency impedance behavior of high impedance connecting links and cables below 1 Hz, revealing additional contributions to capacitance at ultra-low frequencies and proposing an improved model.

Contribution

It introduces a new model that accounts for additional capacitance contributions observed at very low frequencies, extending beyond the traditional parallel RC model.

Findings

Additional capacitance contributions emerge below 1 Hz.

The new model accurately fits impedance data down to 10 μHz.

Traditional models are inadequate at ultra-low frequencies.

Abstract

High impedance connecting links and cables are modeled at low frequency in terms of their impedance to ground and to neigbouring connecting links. The impedance is usually considered to be the parallel combination of a resistance and a capacitance. While this model is adequate at moderate and low frequency, it proved to be not satisfactory at very low frequency, in the fractions of Hz range. Deep characterization was carried out on some samples down to 10 uHz, showing that an additional contribution to capacitance can emerge. A model was developed to explain and account for this additional contribution.