Design of a proper set-up for low current measurements of insulation systems

Abstract

Low-level measurements are an important part of electrical studies. Due to the small values of current and voltage used, the precision of the values becomes very important. For example, a change of 1 nA or 1 nV can make a huge difference. For that reason, measuring those values requires special study and therefore, special attention, procedures, equipment and designs. In this thesis, different ways to measure low current, values of pA and nA, will be analyzed and compared. Currently in the market, devices capable of doing this task do exist, but for a very expensive price. The purpose of this study will be to design an economically affordable device capable of producing acceptable results. The steps outlined in the following pages will focus on measuring polarization current through an isolating system applying a voltage up to 20 kV. Different processes of measuring will be evaluated. In the end, one will be chosen to take the measurements and show them over a multimeter device while simultaneously logging the values in a computer.