Direct methods to measure Transfer Impedance of shielded cables at frequencies below 50MHz

Abstract

In this paper, Direct methods to measure the Transfer Impedance (Z <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> ) also known as Surface Transfer Impedance of HV-Cables are proposed which makes it easy to analyze and improve shielding properties. Proposed Z <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> direct methods are based on Current Probe (CP) and Capacitive Voltage Probe (CVP). Using these Z <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">T</sub> direct methods, critical frequencies can be identified and preventive measures can be implemented. Proposed direct methods are verified by comparing measurement results with other renowned methods like Triaxial Method, Line Injection method and previously proposed Ground Plate Method. In these direct methods, main advantage is the ease of measurement i.e. without making any major variation in the cable under test.