Methodology for Modeling and Correcting the Effects of Extension Cables for Measurements in Low Voltage Grids in the 1.1–10 MHz Frequency Band

The characterization of the grid access impedance, the Non-Intentional Emissions (NIEs) and the attenuation of the Low Voltage (LV) distribution grid is a major factor to be considered for the development of Power Line Communications (PLC) systems. Often, the measurement systems used for this characterization require the placement of extension cables to reach connection points, which greatly affect the results obtained in the MHz frequency range. This paper provides a new methodology for modelling and correcting the effects of the extension cables needed by measurement systems for online impedance measurements from 1.1 to 10 MHz. The proposed methodology has been applied to four different extension cables, assessing its accuracy, and it has been validated against online LV grid access impedance measurements. The results show that there is a great improvement in the error obtained with the proposed methodology over others previously presented.